Karan, L.,Clark, N.
A Path to Creating the First Generation of High Seas Protected Areas Technical Report
no. 130, 2020.
Abstract | Links | BibTeX | Tags: Arabian Sea, biodiversity, Gulf of Guinea, high seas, Madagascar, Marine Protected Area, Mascarene Islands, migration
@techreport{,
title = {A Path to Creating the First Generation of High Seas Protected Areas},
author = {Karan, L.,Clark, N.},
url = {https://www.pewtrusts.org/en/research-and-analysis/reports/2020/03/a-path-to-creating-the-first-generation-of-high-seas-protected-areas},
year = {2020},
date = {2020-01-01},
number = {130},
pages = {42},
publisher = {Pew Charitable Trusts},
abstract = {Beyond the horizon, more than 200 nautical miles from shore, lies an area of the ocean known as the high seas.
These waters, beyond the jurisdiction of any nation, make up roughly two-thirds of the ocean and cover nearly
half of the planet’s surface. Much is still to be learned about these areas, but scientists know they teem with life
and are among the largest reservoirs of ocean biodiversity. The high seas support abundant fisheries; provide
habitat and migratory routes for whales, sharks, sea turtles, and seabirds; and harbor remarkable ecosystems,
such as deep-water corals and other majestic marine life.
The high seas are also an increasingly busy space; rapid advances in technology and increasing demand for
goods and trade in recent decades mean virtually no part of the ocean—including these waters far from shore—
remains untouched by human industrial activity. Currently, a patchwork of different regional and sectoral
organizations manages this last global common space with little coordination among organizations, and that
is leading to the degradation of the marine environment and its resources. These areas belong to everyone, yet
governments currently have no comprehensive legal mechanism in place to protect high seas marine life.
There is an opportunity for this to change. Negotiations are under way at the United Nations to finalize a new
high seas treaty focused on the conservation and sustainable use of marine biological diversity beyond national
jurisdiction. The treaty could allow nations to establish comprehensive, cross-sector marine protected areas
(MPAs) on the high seas. These areas, when well-managed, can be effective tools in building ocean resilience
to climate change, avoiding fisheries collapse, and preserving biodiversity. Currently, less than 1 per cent of
high seas waters are highly protected, but scientific evidence suggests that protecting at least 30 per cent of
the ocean is more likely to achieve long-term ocean health objectives.1 High seas MPAs can play a key role in
reaching this target.
Although there is much still to discover, scientists have sufficient data and research to begin mapping and
modeling hot spots of biodiversity on the high seas.2 This report identifies some of the special places that could
benefit from protections established under a new high seas treaty. The findings build off a project funded by The
Pew Charitable Trusts and led by scientists at the University of California, Santa Barbara (UCSB) in conjunction
with partners from 13 universities and organizations. Using an algorithm that allows for consideration of
multiple factors, researchers developed a data-driven analysis to identify areas in the high seas of outstanding
conservation value.
The 10 sites highlighted represent areas with a spectrum and combination of important features, such as
species richness, productivity, and habitat diversity. They are located in oceans that span the globe.
This report also includes recommendations to inform the negotiations under way to finalize a new legally
binding international agreement. The agreement should ensure the establishment of effective high seas
protections, including by setting meaningful conservation objectives and requiring enforceable management
plans for these critical waters beyond the jurisdiction of any single nation. },
keywords = {Arabian Sea, biodiversity, Gulf of Guinea, high seas, Madagascar, Marine Protected Area, Mascarene Islands, migration},
pubstate = {published},
tppubtype = {techreport}
}
Beyond the horizon, more than 200 nautical miles from shore, lies an area of the ocean known as the high seas.
These waters, beyond the jurisdiction of any nation, make up roughly two-thirds of the ocean and cover nearly
half of the planet’s surface. Much is still to be learned about these areas, but scientists know they teem with life
and are among the largest reservoirs of ocean biodiversity. The high seas support abundant fisheries; provide
habitat and migratory routes for whales, sharks, sea turtles, and seabirds; and harbor remarkable ecosystems,
such as deep-water corals and other majestic marine life.
The high seas are also an increasingly busy space; rapid advances in technology and increasing demand for
goods and trade in recent decades mean virtually no part of the ocean—including these waters far from shore—
remains untouched by human industrial activity. Currently, a patchwork of different regional and sectoral
organizations manages this last global common space with little coordination among organizations, and that
is leading to the degradation of the marine environment and its resources. These areas belong to everyone, yet
governments currently have no comprehensive legal mechanism in place to protect high seas marine life.
There is an opportunity for this to change. Negotiations are under way at the United Nations to finalize a new
high seas treaty focused on the conservation and sustainable use of marine biological diversity beyond national
jurisdiction. The treaty could allow nations to establish comprehensive, cross-sector marine protected areas
(MPAs) on the high seas. These areas, when well-managed, can be effective tools in building ocean resilience
to climate change, avoiding fisheries collapse, and preserving biodiversity. Currently, less than 1 per cent of
high seas waters are highly protected, but scientific evidence suggests that protecting at least 30 per cent of
the ocean is more likely to achieve long-term ocean health objectives.1 High seas MPAs can play a key role in
reaching this target.
Although there is much still to discover, scientists have sufficient data and research to begin mapping and
modeling hot spots of biodiversity on the high seas.2 This report identifies some of the special places that could
benefit from protections established under a new high seas treaty. The findings build off a project funded by The
Pew Charitable Trusts and led by scientists at the University of California, Santa Barbara (UCSB) in conjunction
with partners from 13 universities and organizations. Using an algorithm that allows for consideration of
multiple factors, researchers developed a data-driven analysis to identify areas in the high seas of outstanding
conservation value.
The 10 sites highlighted represent areas with a spectrum and combination of important features, such as
species richness, productivity, and habitat diversity. They are located in oceans that span the globe.
This report also includes recommendations to inform the negotiations under way to finalize a new legally
binding international agreement. The agreement should ensure the establishment of effective high seas
protections, including by setting meaningful conservation objectives and requiring enforceable management
plans for these critical waters beyond the jurisdiction of any single nation.
These waters, beyond the jurisdiction of any nation, make up roughly two-thirds of the ocean and cover nearly
half of the planet’s surface. Much is still to be learned about these areas, but scientists know they teem with life
and are among the largest reservoirs of ocean biodiversity. The high seas support abundant fisheries; provide
habitat and migratory routes for whales, sharks, sea turtles, and seabirds; and harbor remarkable ecosystems,
such as deep-water corals and other majestic marine life.
The high seas are also an increasingly busy space; rapid advances in technology and increasing demand for
goods and trade in recent decades mean virtually no part of the ocean—including these waters far from shore—
remains untouched by human industrial activity. Currently, a patchwork of different regional and sectoral
organizations manages this last global common space with little coordination among organizations, and that
is leading to the degradation of the marine environment and its resources. These areas belong to everyone, yet
governments currently have no comprehensive legal mechanism in place to protect high seas marine life.
There is an opportunity for this to change. Negotiations are under way at the United Nations to finalize a new
high seas treaty focused on the conservation and sustainable use of marine biological diversity beyond national
jurisdiction. The treaty could allow nations to establish comprehensive, cross-sector marine protected areas
(MPAs) on the high seas. These areas, when well-managed, can be effective tools in building ocean resilience
to climate change, avoiding fisheries collapse, and preserving biodiversity. Currently, less than 1 per cent of
high seas waters are highly protected, but scientific evidence suggests that protecting at least 30 per cent of
the ocean is more likely to achieve long-term ocean health objectives.1 High seas MPAs can play a key role in
reaching this target.
Although there is much still to discover, scientists have sufficient data and research to begin mapping and
modeling hot spots of biodiversity on the high seas.2 This report identifies some of the special places that could
benefit from protections established under a new high seas treaty. The findings build off a project funded by The
Pew Charitable Trusts and led by scientists at the University of California, Santa Barbara (UCSB) in conjunction
with partners from 13 universities and organizations. Using an algorithm that allows for consideration of
multiple factors, researchers developed a data-driven analysis to identify areas in the high seas of outstanding
conservation value.
The 10 sites highlighted represent areas with a spectrum and combination of important features, such as
species richness, productivity, and habitat diversity. They are located in oceans that span the globe.
This report also includes recommendations to inform the negotiations under way to finalize a new legally
binding international agreement. The agreement should ensure the establishment of effective high seas
protections, including by setting meaningful conservation objectives and requiring enforceable management
plans for these critical waters beyond the jurisdiction of any single nation.
Pomilla, Cristina,Amaral, Ana R.,Collins, Tim,Minton, Gianna,Findlay, Ken,Leslie, Matthew S.,Ponnampalam, Louisa,Baldwin, Robert,Rosenbaum, Howard
The World's Most Isolated and Distinct Whale Population? Humpback Whales of the Arabian Sea Journal Article
In: PLoS ONE, vol. 9, no. 194, pp. e114162, 2014.
Abstract | Links | BibTeX | Tags: Arabian Sea, Evolution, Genetic differentiation, Humpback Whale, megaptera novaeangliae, migration, population identity, Stock identity, Threats
@article{,
title = {The World's Most Isolated and Distinct Whale Population? Humpback Whales of the Arabian Sea},
author = {Pomilla, Cristina,Amaral, Ana R.,Collins, Tim,Minton, Gianna,Findlay, Ken,Leslie, Matthew S.,Ponnampalam, Louisa,Baldwin, Robert,Rosenbaum, Howard},
url = {http://dx.doi.org/10.1371%2Fjournal.pone.0114162},
year = {2014},
date = {2014-01-01},
journal = {PLoS ONE},
volume = {9},
number = {194},
pages = {e114162},
publisher = {Public Library of Science},
abstract = {A clear understanding of population structure is essential for assessing conservation status and implementing management strategies. A small, non-migratory population of humpback whales in the Arabian Sea is classified as “Endangered” on the IUCN Red List of Threatened Species, an assessment constrained by a lack of data, including limited understanding of its relationship to other populations. We analysed 11 microsatellite markers and mitochondrial DNA sequences extracted from 67 Arabian Sea humpback whale tissue samples and compared them to equivalent datasets from the Southern Hemisphere and North Pacific. Results show that the Arabian Sea population is highly distinct; estimates of gene flow and divergence times suggest a Southern Indian Ocean origin but indicate that it has been isolated for approximately 70,000 years, remarkable for a species that is typically highly migratory. Genetic diversity values are significantly lower than those obtained for Southern Hemisphere populations and signatures of ancient and recent genetic bottlenecks were identified. Our findings suggest this is the world's most isolated humpback whale population, which, when combined with low population abundance estimates and anthropogenic threats, raises concern for its survival. We recommend an amendment of the status of the population to “Critically Endangered” on the IUCN Red List.
},
keywords = {Arabian Sea, Evolution, Genetic differentiation, Humpback Whale, megaptera novaeangliae, migration, population identity, Stock identity, Threats},
pubstate = {published},
tppubtype = {article}
}
A clear understanding of population structure is essential for assessing conservation status and implementing management strategies. A small, non-migratory population of humpback whales in the Arabian Sea is classified as “Endangered” on the IUCN Red List of Threatened Species, an assessment constrained by a lack of data, including limited understanding of its relationship to other populations. We analysed 11 microsatellite markers and mitochondrial DNA sequences extracted from 67 Arabian Sea humpback whale tissue samples and compared them to equivalent datasets from the Southern Hemisphere and North Pacific. Results show that the Arabian Sea population is highly distinct; estimates of gene flow and divergence times suggest a Southern Indian Ocean origin but indicate that it has been isolated for approximately 70,000 years, remarkable for a species that is typically highly migratory. Genetic diversity values are significantly lower than those obtained for Southern Hemisphere populations and signatures of ancient and recent genetic bottlenecks were identified. Our findings suggest this is the world's most isolated humpback whale population, which, when combined with low population abundance estimates and anthropogenic threats, raises concern for its survival. We recommend an amendment of the status of the population to “Critically Endangered” on the IUCN Red List.
Mendez, M.,Subramaniam, A.,Collins, T.,Minton, G.,Baldwin, R.,Berggren, P.,Sa¨rnblad, A.,Amir, O. A.,Peddemors, V.,Karczmarski, L.,Guissamulo, A.,Rosenbaum, H.C.
Molecular ecology meets remote sensing: environmental drivers to population structure of humpback dolphins in the Western Indian Ocean Journal Article
In: Heredity, no. 404, pp. 1-13, 2011.
Abstract | BibTeX | Tags: Genetic differentiation, indopacific humpback dolphin, migration, population structure, remote sensing, sousa, Sousa chinensis
@article{,
title = {Molecular ecology meets remote sensing: environmental drivers to population structure of humpback dolphins in the Western Indian Ocean},
author = {Mendez, M.,Subramaniam, A.,Collins, T.,Minton, G.,Baldwin, R.,Berggren, P.,Sa¨rnblad, A.,Amir, O. A.,Peddemors, V.,Karczmarski, L.,Guissamulo, A.,Rosenbaum, H.C.},
year = {2011},
date = {2011-01-01},
journal = {Heredity},
number = {404},
pages = {1-13},
abstract = {Genetic analyses of population structure can be placed in
explicit environmental contexts if appropriate environmental
data are available. Here, we use high-coverage and highresolution
oceanographic and genetic sequence data to
assess population structure patterns and their potential
environmental influences for humpback dolphins in the
Western Indian Ocean. We analyzed mitochondrial DNA
data from 94 dolphins from the coasts of South Africa,
Mozambique, Tanzania and Oman, employing frequencybased
and maximum-likelihood algorithms to assess population
structure and migration patterns. The genetic data were
combined with 13 years of remote sensing oceanographic
data of variables known to influence cetacean dispersal and
population structure. Our analyses show strong and highly
significant genetic structure between all putative populations,
except for those in South Africa and Mozambique. Interestingly,
the oceanographic data display marked environmental
heterogeneity between all sampling areas and a degree of
overlap between South Africa and Mozambique. Our
combined analyses therefore suggest the occurrence of
genetically isolated populations of humpback dolphins in
areas that are environmentally distinct. This study highlights
the utility of molecular tools in combination with highresolution
and high-coverage environmental data to address
questions not only pertaining to genetic population structure,
but also to relevant ecological processes in marine species},
keywords = {Genetic differentiation, indopacific humpback dolphin, migration, population structure, remote sensing, sousa, Sousa chinensis},
pubstate = {published},
tppubtype = {article}
}
Genetic analyses of population structure can be placed in
explicit environmental contexts if appropriate environmental
data are available. Here, we use high-coverage and highresolution
oceanographic and genetic sequence data to
assess population structure patterns and their potential
environmental influences for humpback dolphins in the
Western Indian Ocean. We analyzed mitochondrial DNA
data from 94 dolphins from the coasts of South Africa,
Mozambique, Tanzania and Oman, employing frequencybased
and maximum-likelihood algorithms to assess population
structure and migration patterns. The genetic data were
combined with 13 years of remote sensing oceanographic
data of variables known to influence cetacean dispersal and
population structure. Our analyses show strong and highly
significant genetic structure between all putative populations,
except for those in South Africa and Mozambique. Interestingly,
the oceanographic data display marked environmental
heterogeneity between all sampling areas and a degree of
overlap between South Africa and Mozambique. Our
combined analyses therefore suggest the occurrence of
genetically isolated populations of humpback dolphins in
areas that are environmentally distinct. This study highlights
the utility of molecular tools in combination with highresolution
and high-coverage environmental data to address
questions not only pertaining to genetic population structure,
but also to relevant ecological processes in marine species
explicit environmental contexts if appropriate environmental
data are available. Here, we use high-coverage and highresolution
oceanographic and genetic sequence data to
assess population structure patterns and their potential
environmental influences for humpback dolphins in the
Western Indian Ocean. We analyzed mitochondrial DNA
data from 94 dolphins from the coasts of South Africa,
Mozambique, Tanzania and Oman, employing frequencybased
and maximum-likelihood algorithms to assess population
structure and migration patterns. The genetic data were
combined with 13 years of remote sensing oceanographic
data of variables known to influence cetacean dispersal and
population structure. Our analyses show strong and highly
significant genetic structure between all putative populations,
except for those in South Africa and Mozambique. Interestingly,
the oceanographic data display marked environmental
heterogeneity between all sampling areas and a degree of
overlap between South Africa and Mozambique. Our
combined analyses therefore suggest the occurrence of
genetically isolated populations of humpback dolphins in
areas that are environmentally distinct. This study highlights
the utility of molecular tools in combination with highresolution
and high-coverage environmental data to address
questions not only pertaining to genetic population structure,
but also to relevant ecological processes in marine species
Rosenbaum, H.C.,Pomilla, C.,Mendez, M.C.,Leslie, M.,Best, P.,Findlay, K.,Minton, G.,Ersts, P.J.,Collins, T.,Engel, M.H.,Bonatto, S.,Kotze, D.,Meyer, M.,Barendse, J.,Thornton, M.,Razafindrakoto, Y.,Ngouessono, S,Vely, M.,Kiszka, J.
Population Structure of Humpback Whales from Their Breeding Grounds in the South Atlantic and Indian Oceans Journal Article
In: PLoS ONE, vol. 4, no. 460, pp. e7318. doi:10.1371/journal.pone.0007318, 2009.
Abstract | Links | BibTeX | Tags: Arabian Sea, Humpback Whale, Indian Ocean, megaptera novaeangliae, migration, mtDNA, Oman, population identity, population structure, Population X, Southern Hemisphere
@article{,
title = {Population Structure of Humpback Whales from Their Breeding Grounds in the South Atlantic and Indian Oceans},
author = {Rosenbaum, H.C.,Pomilla, C.,Mendez, M.C.,Leslie, M.,Best, P.,Findlay, K.,Minton, G.,Ersts, P.J.,Collins, T.,Engel, M.H.,Bonatto, S.,Kotze, D.,Meyer, M.,Barendse, J.,Thornton, M.,Razafindrakoto, Y.,Ngouessono, S,Vely, M.,Kiszka, J.},
url = {https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0007318},
year = {2009},
date = {2009-01-01},
journal = {PLoS ONE},
volume = {4},
number = {460},
pages = {e7318. doi:10.1371/journal.pone.0007318},
abstract = {Although humpback whales are among the best-studied of the large whales, population boundaries in the Southern
Hemisphere (SH) have remained largely untested. We assess population structure of SH humpback whales using 1,527
samples collected from whales at fourteen sampling sites within the Southwestern and Southeastern Atlantic, the
Southwestern Indian Ocean, and Northern Indian Ocean (Breeding Stocks A, B, C and X, respectively). Evaluation of mtDNA
population structure and migration rates was carried out under different statistical frameworks. Using all genetic evidence,
the results suggest significant degrees of population structure between all ocean basins, with the Southwestern and
Northern Indian Ocean most differentiated from each other. Effective migration rates were highest between the
Southeastern Atlantic and the Southwestern Indian Ocean, followed by rates within the Southeastern Atlantic, and the
lowest between the Southwestern and Northern Indian Ocean. At finer scales, very low gene flow was detected between
the two neighbouring sub-regions in the Southeastern Atlantic, compared to high gene flow for whales within the
Southwestern Indian Ocean. Our genetic results support the current management designations proposed by the
International Whaling Commission of Breeding Stocks A, B, C, and X as four strongly structured populations. The population
structure patterns found in this study are likely to have been influenced by a combination of long-term maternally directed
fidelity of migratory destinations, along with other ecological and oceanographic features in the region.},
keywords = {Arabian Sea, Humpback Whale, Indian Ocean, megaptera novaeangliae, migration, mtDNA, Oman, population identity, population structure, Population X, Southern Hemisphere},
pubstate = {published},
tppubtype = {article}
}
Although humpback whales are among the best-studied of the large whales, population boundaries in the Southern
Hemisphere (SH) have remained largely untested. We assess population structure of SH humpback whales using 1,527
samples collected from whales at fourteen sampling sites within the Southwestern and Southeastern Atlantic, the
Southwestern Indian Ocean, and Northern Indian Ocean (Breeding Stocks A, B, C and X, respectively). Evaluation of mtDNA
population structure and migration rates was carried out under different statistical frameworks. Using all genetic evidence,
the results suggest significant degrees of population structure between all ocean basins, with the Southwestern and
Northern Indian Ocean most differentiated from each other. Effective migration rates were highest between the
Southeastern Atlantic and the Southwestern Indian Ocean, followed by rates within the Southeastern Atlantic, and the
lowest between the Southwestern and Northern Indian Ocean. At finer scales, very low gene flow was detected between
the two neighbouring sub-regions in the Southeastern Atlantic, compared to high gene flow for whales within the
Southwestern Indian Ocean. Our genetic results support the current management designations proposed by the
International Whaling Commission of Breeding Stocks A, B, C, and X as four strongly structured populations. The population
structure patterns found in this study are likely to have been influenced by a combination of long-term maternally directed
fidelity of migratory destinations, along with other ecological and oceanographic features in the region.
Hemisphere (SH) have remained largely untested. We assess population structure of SH humpback whales using 1,527
samples collected from whales at fourteen sampling sites within the Southwestern and Southeastern Atlantic, the
Southwestern Indian Ocean, and Northern Indian Ocean (Breeding Stocks A, B, C and X, respectively). Evaluation of mtDNA
population structure and migration rates was carried out under different statistical frameworks. Using all genetic evidence,
the results suggest significant degrees of population structure between all ocean basins, with the Southwestern and
Northern Indian Ocean most differentiated from each other. Effective migration rates were highest between the
Southeastern Atlantic and the Southwestern Indian Ocean, followed by rates within the Southeastern Atlantic, and the
lowest between the Southwestern and Northern Indian Ocean. At finer scales, very low gene flow was detected between
the two neighbouring sub-regions in the Southeastern Atlantic, compared to high gene flow for whales within the
Southwestern Indian Ocean. Our genetic results support the current management designations proposed by the
International Whaling Commission of Breeding Stocks A, B, C, and X as four strongly structured populations. The population
structure patterns found in this study are likely to have been influenced by a combination of long-term maternally directed
fidelity of migratory destinations, along with other ecological and oceanographic features in the region.
Ashjian,C.J.,Smtih,S.L.,Flagg,C.N.,Idrisi,N.
Distribution, annual cycle, and vertical migration of acoustically derived biomass in the Arabian Sea during 1994-1995 Journal Article
In: Deep-Sea Research Part II, vol. 49, no. 299, pp. 2377-2402, 2002.
Abstract | BibTeX | Tags: acoustic, Arabian Sea, diel, Distribution, history, life history, migration, myctophids, Oceanic, Oman, predation, seasonal change, stocks, Upwelling, zooplankton
@article{,
title = {Distribution, annual cycle, and vertical migration of acoustically derived biomass in the Arabian Sea during 1994-1995},
author = {Ashjian,C.J.,Smtih,S.L.,Flagg,C.N.,Idrisi,N.},
year = {2002},
date = {2002-01-01},
journal = {Deep-Sea Research Part II},
volume = {49},
number = {299},
pages = {2377-2402},
abstract = {The distinguishing characteristic that sets the Arabian Sea apart from other oceanic regions is the regular oscillation of monsoonal atmospheric conditions that produces predictable periods of upwelling or convective mixing, with associated biological response, during the Southwest and Northeast monsoons, respectively. This oscillation is also evident in cycles of standing stocks of zooplankton and micronekton. The vertical distribution and spatial pattern of zooplankton and micronekton biomass were estimated using an acoustic Doppler current profiler along a 1000-km transect extending from the continental shelf of Oman to the central Arabian Sea during ten cruises on the R/V Thomas G. Thompson (November 1994-December 1995). The influence of the Southwest Monsoon, and accompanying upwelling and enhanced acoustically derived biomass, was the dominant feature in the spatial-temporal distributions of both zooplankton and micronekton near the Omani coast. The diel vertical migration of predators (myctophids, pelagic crabs), and the seasonal changes in the strength of this signal, was the most significant pattern observed in the vertical distribution of biomass and imparted a strong day-night signal to the integrated upper water-column biomass. Significant differences in the magnitude of integrated upper water-column biomass, both zooplankton (day) and migrator-zooplankton (night), were seen between inshore and offshore of the atmospheric Findlater Jet. A station located in the central Arabian Sea demonstrated seasonal changes in biomass over the year, despite being quite far from the influence of the monsoonal oscillations. Predation pressure was greater offshore of the Findlater Jet than in the region inshore of the Jet or in the central Arabian Sea. The pelagic community of the Arabian Sea may have evolved life history strategies to coincide with the predictable monsoonal cycle},
keywords = {acoustic, Arabian Sea, diel, Distribution, history, life history, migration, myctophids, Oceanic, Oman, predation, seasonal change, stocks, Upwelling, zooplankton},
pubstate = {published},
tppubtype = {article}
}
The distinguishing characteristic that sets the Arabian Sea apart from other oceanic regions is the regular oscillation of monsoonal atmospheric conditions that produces predictable periods of upwelling or convective mixing, with associated biological response, during the Southwest and Northeast monsoons, respectively. This oscillation is also evident in cycles of standing stocks of zooplankton and micronekton. The vertical distribution and spatial pattern of zooplankton and micronekton biomass were estimated using an acoustic Doppler current profiler along a 1000-km transect extending from the continental shelf of Oman to the central Arabian Sea during ten cruises on the R/V Thomas G. Thompson (November 1994-December 1995). The influence of the Southwest Monsoon, and accompanying upwelling and enhanced acoustically derived biomass, was the dominant feature in the spatial-temporal distributions of both zooplankton and micronekton near the Omani coast. The diel vertical migration of predators (myctophids, pelagic crabs), and the seasonal changes in the strength of this signal, was the most significant pattern observed in the vertical distribution of biomass and imparted a strong day-night signal to the integrated upper water-column biomass. Significant differences in the magnitude of integrated upper water-column biomass, both zooplankton (day) and migrator-zooplankton (night), were seen between inshore and offshore of the atmospheric Findlater Jet. A station located in the central Arabian Sea demonstrated seasonal changes in biomass over the year, despite being quite far from the influence of the monsoonal oscillations. Predation pressure was greater offshore of the Findlater Jet than in the region inshore of the Jet or in the central Arabian Sea. The pelagic community of the Arabian Sea may have evolved life history strategies to coincide with the predictable monsoonal cycle
Hitchcock,G.L.,Lane,P.,Smith,S.,Luo,J.G.,Ortner,P.B.
Zooplankton spatial distributions in coastal waters of the northern Arabian Sea, August 1995 Journal Article
In: Deep-Sea Research Part II, vol. 49, no. 387, pp. 2403-2423, 2002.
Abstract | BibTeX | Tags: acoustic, Arabian Sea, displacement, Distribution, migration, Oman, surface temperature, temperature, trend, Upwelling, zooplankton
@article{,
title = {Zooplankton spatial distributions in coastal waters of the northern Arabian Sea, August 1995},
author = {Hitchcock,G.L.,Lane,P.,Smith,S.,Luo,J.G.,Ortner,P.B.},
year = {2002},
date = {2002-01-01},
journal = {Deep-Sea Research Part II},
volume = {49},
number = {387},
pages = {2403-2423},
abstract = {The spatial distribution of zooplankton biomass was surveyed in coastal waters of the northern Arabian Sea during the 1995 Southwest Monsoon (August) on cruise MB 95-06 of the NOAA Ship Malcolm Baldrige. Vertical patterns of displacement volumes from a limited set of paired day-night MOCNESS tows suggest there was little diel vertical migration in the coastal waters off the southern Arabian Peninsula. Zooplankton biomass varied from 5.2 to 15.1 9 dw m(-2) (178-517mM Cm-2) in the upper 200-300m of Omani coastal waters. Distributions of acoustic backscatter were mapped in eight daytime acoustic Doppler current profiler transects in coastal waters off Oman and Somalia. Several transects contained maxima in acoustic backscatter that coincided with cool, fresh surface features that were several tens of kilometers wide. Although there was considerable scatter in the relationship between acoustically determined biomass (ADB) of zooplankton and surface temperature, there was a trend of increased biomass in the cool surface temperatures of the Omani upwelling zone. Acoustic transects crossed two filaments that extended seaward from upwelling centers off Oman and Somalia. Estimated zooplankton ADB exported from the upwelling zones in the surface features was on the order of 300 kg dw s( -1 ). The physical and biological characteristics of filaments maintain zooplankton associated with upwelling areas, such as Calanoides carinatus, as they are advected offshore from coastal upwelling zones. (C) 2002 Published by Elsevier Science Ltd.},
keywords = {acoustic, Arabian Sea, displacement, Distribution, migration, Oman, surface temperature, temperature, trend, Upwelling, zooplankton},
pubstate = {published},
tppubtype = {article}
}
The spatial distribution of zooplankton biomass was surveyed in coastal waters of the northern Arabian Sea during the 1995 Southwest Monsoon (August) on cruise MB 95-06 of the NOAA Ship Malcolm Baldrige. Vertical patterns of displacement volumes from a limited set of paired day-night MOCNESS tows suggest there was little diel vertical migration in the coastal waters off the southern Arabian Peninsula. Zooplankton biomass varied from 5.2 to 15.1 9 dw m(-2) (178-517mM Cm-2) in the upper 200-300m of Omani coastal waters. Distributions of acoustic backscatter were mapped in eight daytime acoustic Doppler current profiler transects in coastal waters off Oman and Somalia. Several transects contained maxima in acoustic backscatter that coincided with cool, fresh surface features that were several tens of kilometers wide. Although there was considerable scatter in the relationship between acoustically determined biomass (ADB) of zooplankton and surface temperature, there was a trend of increased biomass in the cool surface temperatures of the Omani upwelling zone. Acoustic transects crossed two filaments that extended seaward from upwelling centers off Oman and Somalia. Estimated zooplankton ADB exported from the upwelling zones in the surface features was on the order of 300 kg dw s( -1 ). The physical and biological characteristics of filaments maintain zooplankton associated with upwelling areas, such as Calanoides carinatus, as they are advected offshore from coastal upwelling zones. (C) 2002 Published by Elsevier Science Ltd.
Rosenbaum,H.C.,Collins,T.J.Q.,Minton,G.,Baldwin,R.,Glaberman,S.,Findlay,K.P.,Best,P.
Preliminary analysis of MtDNA variation among humpback whales off the coast of Oman and their relationships to whales from wintering grounds in the southwestern Indian Ocean Technical Report
no. 458, 2002, ISBN: SC/54/H4.
Abstract | BibTeX | Tags: Arabian Sea, genotyping, humpback whales, Indian Ocean, Madagascar, Mayotte, migration, Oman, population characteristics, South Africa, whaling
@techreport{,
title = {Preliminary analysis of MtDNA variation among humpback whales off the coast of Oman and their relationships to whales from wintering grounds in the southwestern Indian Ocean},
author = {Rosenbaum,H.C.,Collins,T.J.Q.,Minton,G.,Baldwin,R.,Glaberman,S.,Findlay,K.P.,Best,P.},
issn = {SC/54/H4},
year = {2002},
date = {2002-01-01},
journal = {Document presented to the 54th meeting of the International Whaling Commission},
volume = {SC/54/H4},
number = {458},
pages = {1-10},
abstract = {Preliminary results of genetic analysis of skin tissue samples obtained from two sampling locations off the coast of Oman are compared with those obtained form longer term surveys in Madagascar, Mayotte, Mozambique and the east coast of South Africa. Haplotype diversity was relatively low for whales from Oman in comparison with other populations. Maternal lineage haplotypes were shared between whales from both sites in Oman and those of other populations. However, it is unclear whether these shared haplotypes indicate recent exchange/migration links between the Arabian Sea and SW Indian Ocean populations, or are the result of ancestral polymorphism from historical population expansion. Two private material lineage haplotypes were detected in Oman, represented by three individual whales.},
keywords = {Arabian Sea, genotyping, humpback whales, Indian Ocean, Madagascar, Mayotte, migration, Oman, population characteristics, South Africa, whaling},
pubstate = {published},
tppubtype = {techreport}
}
Preliminary results of genetic analysis of skin tissue samples obtained from two sampling locations off the coast of Oman are compared with those obtained form longer term surveys in Madagascar, Mayotte, Mozambique and the east coast of South Africa. Haplotype diversity was relatively low for whales from Oman in comparison with other populations. Maternal lineage haplotypes were shared between whales from both sites in Oman and those of other populations. However, it is unclear whether these shared haplotypes indicate recent exchange/migration links between the Arabian Sea and SW Indian Ocean populations, or are the result of ancestral polymorphism from historical population expansion. Two private material lineage haplotypes were detected in Oman, represented by three individual whales.
Best,P.B.
Distribution and population separation of Bryde's whale Balaenoptera edeni off southern Africa Journal Article
In: Marine Ecology Progress Series, vol. 220, no. 44, pp. 277-289, 2001.
Abstract | BibTeX | Tags: Arabian Sea, Bryde's whale, Distribution, Indian Ocean, length, Madagascar, migration, population characteristics, reproduction, sexual maturity, South Africa, whaling
@article{,
title = {Distribution and population separation of Bryde's whale Balaenoptera edeni off southern Africa},
author = {Best,P.B.},
year = {2001},
date = {2001-01-01},
journal = {Marine Ecology Progress Series},
volume = {220},
number = {44},
pages = {277-289},
abstract = {A review of available catch and biological data suggests that there are 3 populations of Bryde's whales in the Southern African region. An inshore population (the South African Inshore stock) occurs over hte continental shelf of South Africa, south of about 30§ S and seems to be non-migratory, although there is a movement up the west coast in winter. A pelagic population (the South-east Atlantic Stock) occurs on the west coast of southern Africa, ranging from equatorial regions to about 34§ S, and appears to migrate north in autumn and south in spring. Whales from the Southeast Atlantic Stock differ from the South African Inshore Stock in size, scarring, baleen shape, seasonality of reproduction, fecundity and prey types. both occured in the west coast whaling ground off Donkergat, but with differing seasonalities and distributions from the coast. Bryde's whales are rare on the east coast of southern Africa, but are found in summer in some numbers south of Madagascar. Whales from this population are clearly smaller than those from the Southeast Atlantic Stock, but are similar in size to, or even smaller than, those from teh South African Inshore stock. Their external appearance is unknown, but they differ in prey type from South African Inshore stock, and because of a clear discontinuity in distribution, it is believed that they form a third (pelagic) population (the Southwest Indian Ocean Sstock). this population may or may not move normt as far as the Seychelles in winter, but seems to be separate from Bryde's whales in the Arabian Sea. From their size composition, length at sexual maturity and infrequent capture, Bryde's whales taken at Durban may have repasented strays from ei ther ht eh South African Inshore Stock or the Southwest Indian Ocean Stock, and recorded stomach contents also indicate prey ty pes commn toe either stock. The unusual degree of population differentiation shown by Bryde's whales may be a consequence of hteir limited seasonal migrations and apparent resource partitioning.},
keywords = {Arabian Sea, Bryde's whale, Distribution, Indian Ocean, length, Madagascar, migration, population characteristics, reproduction, sexual maturity, South Africa, whaling},
pubstate = {published},
tppubtype = {article}
}
A review of available catch and biological data suggests that there are 3 populations of Bryde's whales in the Southern African region. An inshore population (the South African Inshore stock) occurs over hte continental shelf of South Africa, south of about 30§ S and seems to be non-migratory, although there is a movement up the west coast in winter. A pelagic population (the South-east Atlantic Stock) occurs on the west coast of southern Africa, ranging from equatorial regions to about 34§ S, and appears to migrate north in autumn and south in spring. Whales from the Southeast Atlantic Stock differ from the South African Inshore Stock in size, scarring, baleen shape, seasonality of reproduction, fecundity and prey types. both occured in the west coast whaling ground off Donkergat, but with differing seasonalities and distributions from the coast. Bryde's whales are rare on the east coast of southern Africa, but are found in summer in some numbers south of Madagascar. Whales from this population are clearly smaller than those from the Southeast Atlantic Stock, but are similar in size to, or even smaller than, those from teh South African Inshore stock. Their external appearance is unknown, but they differ in prey type from South African Inshore stock, and because of a clear discontinuity in distribution, it is believed that they form a third (pelagic) population (the Southwest Indian Ocean Sstock). this population may or may not move normt as far as the Seychelles in winter, but seems to be separate from Bryde's whales in the Arabian Sea. From their size composition, length at sexual maturity and infrequent capture, Bryde's whales taken at Durban may have repasented strays from ei ther ht eh South African Inshore Stock or the Southwest Indian Ocean Stock, and recorded stomach contents also indicate prey ty pes commn toe either stock. The unusual degree of population differentiation shown by Bryde's whales may be a consequence of hteir limited seasonal migrations and apparent resource partitioning.
Butler,M.,Bollens,S.M.,Burghalter,B.,Madin,L.P.,Horgan,E.
Mesopelagic fishes of the Arabian Sea: distribution, abundance and diet of Journal Article
In: Deep-Sea Research Part II, vol. 48, no. 61, pp. 1369-1383, 2001.
Abstract | BibTeX | Tags: abundance, Arabian Sea, diel, diet, diets, Distribution, ecology, feeding, migration, oxygen minimum, population, populations, predation, south
@article{,
title = {Mesopelagic fishes of the Arabian Sea: distribution, abundance and diet of },
author = {Butler,M.,Bollens,S.M.,Burghalter,B.,Madin,L.P.,Horgan,E.},
year = {2001},
date = {2001-01-01},
journal = {Deep-Sea Research Part II},
volume = {48},
number = {61},
pages = {1369-1383},
abstract = {Four species of predatory fishes - Chauliodus pammelas, Chauliodus sloani, Stomias afffnis and Stomias nebulosus - were collected on two cruises to the Arabian Sea during 1995. We present data on the abundances, horizontal and vertical distributions, and diet of these fishes. We also discuss briefly the importance of the oxygen minimum zone and predation on myctophid fishes to the ecology of these mesopelagic predators. Chauliodus pammelas and C. sloani appear to have only partially overlapping horizontal distributions in the Arabian Sea, with C. pammelas more common to the north and C. sloani more common to the south. Our data support previous results suggesting that diel vertical migration is the norm for these species, with smaller individuals usually nearer to the surface and larger individuals tending to stay deeper. In contrast to Chauliodus, Stomias affinis and S. nebulosus appear to have largely overlapping horizontal distributions in the Arabian Sea. However, they may have slightly di!erent vertical distributions, with S. affinis living slightly shallower (especially at night) than S. nebulosus. All four species spend most of their time in the oxygen minimum zone, entering the surface oxygenated waters (100-150 m) only at night (if at all). The diets of C. pammelas, C. sloani, and S. affinis consisted mainly of lantern fishes, Myctophidae, and other fishes. In contrast, S. nebulosus, the smaller of the two Stomias species, ate mostly copepods and other crustaceans. This differential feeding may allow the two Stomias species to co-occur. Three of these four stomiids appear to play an important role in predation on myctophid fish populations in the Arabian Sea.},
keywords = {abundance, Arabian Sea, diel, diet, diets, Distribution, ecology, feeding, migration, oxygen minimum, population, populations, predation, south},
pubstate = {published},
tppubtype = {article}
}
Four species of predatory fishes - Chauliodus pammelas, Chauliodus sloani, Stomias afffnis and Stomias nebulosus - were collected on two cruises to the Arabian Sea during 1995. We present data on the abundances, horizontal and vertical distributions, and diet of these fishes. We also discuss briefly the importance of the oxygen minimum zone and predation on myctophid fishes to the ecology of these mesopelagic predators. Chauliodus pammelas and C. sloani appear to have only partially overlapping horizontal distributions in the Arabian Sea, with C. pammelas more common to the north and C. sloani more common to the south. Our data support previous results suggesting that diel vertical migration is the norm for these species, with smaller individuals usually nearer to the surface and larger individuals tending to stay deeper. In contrast to Chauliodus, Stomias affinis and S. nebulosus appear to have largely overlapping horizontal distributions in the Arabian Sea. However, they may have slightly di!erent vertical distributions, with S. affinis living slightly shallower (especially at night) than S. nebulosus. All four species spend most of their time in the oxygen minimum zone, entering the surface oxygenated waters (100-150 m) only at night (if at all). The diets of C. pammelas, C. sloani, and S. affinis consisted mainly of lantern fishes, Myctophidae, and other fishes. In contrast, S. nebulosus, the smaller of the two Stomias species, ate mostly copepods and other crustaceans. This differential feeding may allow the two Stomias species to co-occur. Three of these four stomiids appear to play an important role in predation on myctophid fish populations in the Arabian Sea.
Madhupratap,M.,Gopalakrishnan,T.C.,Haridas,P.,Nair,K.K.C.
Mesozooplankton biomass, composition and distribution in the Arabian Sea during the Fall Intermonsoon: implications of oxygen gradients Journal Article
In: Deep-Sea Research Part II, vol. 48, no. 146, pp. 1345-1368, 2001.
Abstract | BibTeX | Tags: Arabian Sea, depth, diel, Distribution, migration, oxygen minimum, seasonal variation, south, thermocline
@article{,
title = {Mesozooplankton biomass, composition and distribution in the Arabian Sea during the Fall Intermonsoon: implications of oxygen gradients},
author = {Madhupratap,M.,Gopalakrishnan,T.C.,Haridas,P.,Nair,K.K.C.},
year = {2001},
date = {2001-01-01},
journal = {Deep-Sea Research Part II},
volume = {48},
number = {146},
pages = {1345-1368},
abstract = {Mesozooplankton biomass and distribution of calanoid copepods were studied for the upper 500m between 3 and 21§N along an open-ocean transect in the Arabian Sea during the Fall Intermonsoon (September-October 1992, 1993). The region studied has strong gradients in the oxygen minimum zone (OMZ), being acutely deficient in oxygen in the north and with increasing concentrations towards the south. In the upper layers, mesozooplankton biomass was higher in the northern latitudes, above the thermocline, apparently avoiding the OMZ. In the deeper strata, relatively higher biomass was observed in the more oxygenated southern latitudes. Highest mesozooplankton biomass in open waters of the Arabian Sea was observed during the intermonsoon seasons. Calanoid copepods occurred at all depths, and surface-living species did not undertake conspicuous diel migrations, even when they occurred in the deeper waters of the more southern latitudes. A few species belonging to the families Metridinidae and Augaptilidae appeared to be characteristic of the poorly oxygenated mid-depths of the more northern latitudes. Seasonal variations in the composition of the copepod community were negligible. The evolution of the OMZ in the Arabian Sea and its implications are discussed.},
keywords = {Arabian Sea, depth, diel, Distribution, migration, oxygen minimum, seasonal variation, south, thermocline},
pubstate = {published},
tppubtype = {article}
}
Mesozooplankton biomass and distribution of calanoid copepods were studied for the upper 500m between 3 and 21§N along an open-ocean transect in the Arabian Sea during the Fall Intermonsoon (September-October 1992, 1993). The region studied has strong gradients in the oxygen minimum zone (OMZ), being acutely deficient in oxygen in the north and with increasing concentrations towards the south. In the upper layers, mesozooplankton biomass was higher in the northern latitudes, above the thermocline, apparently avoiding the OMZ. In the deeper strata, relatively higher biomass was observed in the more oxygenated southern latitudes. Highest mesozooplankton biomass in open waters of the Arabian Sea was observed during the intermonsoon seasons. Calanoid copepods occurred at all depths, and surface-living species did not undertake conspicuous diel migrations, even when they occurred in the deeper waters of the more southern latitudes. A few species belonging to the families Metridinidae and Augaptilidae appeared to be characteristic of the poorly oxygenated mid-depths of the more northern latitudes. Seasonal variations in the composition of the copepod community were negligible. The evolution of the OMZ in the Arabian Sea and its implications are discussed.
De Silva, Rex
Notes on a possible mas-migration of marine species off the west coast of Sri Lanka Journal Article
In: LORIS (Journal of the Wildlife and Nature Protection Society of Sri Lanka)., vol. 22 , no. 81, pp. 39-41, 2000.
Abstract | BibTeX | Tags: Arabian Sea, feeding, Humpback Whale, megaptera novaeangliae, migration, platforms of opportunity, Sri Lanka
@article{,
title = {Notes on a possible mas-migration of marine species off the west coast of Sri Lanka},
author = {De Silva, Rex},
year = {2000},
date = {2000-01-01},
journal = {LORIS (Journal of the Wildlife and Nature Protection Society of Sri Lanka).},
volume = {22 },
number = {81},
pages = {39-41},
abstract = {THis paper suggests the possibility that a mass-migration of marine species, including Humpback Whales, several species of seabirds including Bridled Terns and Scalloped Hammergead Sharks, may be a regular occurrence off Sri Lanka's coastal waters. It suggests the need for further research.},
keywords = {Arabian Sea, feeding, Humpback Whale, megaptera novaeangliae, migration, platforms of opportunity, Sri Lanka},
pubstate = {published},
tppubtype = {article}
}
THis paper suggests the possibility that a mass-migration of marine species, including Humpback Whales, several species of seabirds including Bridled Terns and Scalloped Hammergead Sharks, may be a regular occurrence off Sri Lanka's coastal waters. It suggests the need for further research.
Luo,J.,Ortner,P.B.,Forcucci,D.,Cummings,S.R.
Diel vertical migration of zooplankton and mesopelagic fish in the Arabian Sea Journal Article
In: Deep-Sea Research Part II, vol. 47 , no. 145, pp. 1451-1473, 2000.
Abstract | BibTeX | Tags: acoustic, Arabian Sea, depth, diel, displacement, fish, migration, oxygen minimum, sonar, temperature, zooplankton
@article{,
title = {Diel vertical migration of zooplankton and mesopelagic fish in the Arabian Sea},
author = {Luo,J.,Ortner,P.B.,Forcucci,D.,Cummings,S.R.},
year = {2000},
date = {2000-01-01},
journal = {Deep-Sea Research Part II},
volume = {47 },
number = {145},
pages = {1451-1473},
abstract = {Acoustic (153 kHz ADCP and 12 kHz hull-mounted transducers) data and MOCNESS (MOC01 and MOC10) net tow samples collected in the Arabian Sea during the Spring Intermonsoon (April/May) and Southwest Monsoon (August) in 1995 documented substantial diel migrations of fish and zooplankton despite the year-round presence of an oxygen minimum ((0.2 ml l-1 at 125-150 m). Fish and zooplankton layers were distinguished by comparing 12 kHz sonar and 153 kHz ADCP backscatter data, which indicated that the strongly migrating layers were predominantly composed of fishes. Fish vertical migration speeds were independently estimated from the slopes of the volume scattering layers and from the vertical velocity components of the ADCP, yielding average speeds of 4 and 3 cm s-1 and maximum speeds of 13 and 10 cm s-1, respectively. A few migrating zooplankton layers were identified with an average speed of about 2 cm s-1 and maximum speeds as high as 8 cm s-1. Migration depths for both zooplankton and fish differed somewhat amongst stations and appeared to be related to local hydrographic conditions (principally the vertical gradients in DO and water temperature). Zooplankton displacement volumes at individual sites suggested that zooplankton biomass during the Southwest Monsoon could be as much as fivefold greater than during the Spring Intermonsoon. This observation was confirmed for the region in general by first deriving a relationship between ADCP backscatter intensity and daytime zooplankton biomass and then comparing the latter between cruises using daytime ADCP data taken along a 1500 km transect that extended from the coast of Somalia to the center of the northern basin.},
keywords = {acoustic, Arabian Sea, depth, diel, displacement, fish, migration, oxygen minimum, sonar, temperature, zooplankton},
pubstate = {published},
tppubtype = {article}
}
Acoustic (153 kHz ADCP and 12 kHz hull-mounted transducers) data and MOCNESS (MOC01 and MOC10) net tow samples collected in the Arabian Sea during the Spring Intermonsoon (April/May) and Southwest Monsoon (August) in 1995 documented substantial diel migrations of fish and zooplankton despite the year-round presence of an oxygen minimum ((0.2 ml l-1 at 125-150 m). Fish and zooplankton layers were distinguished by comparing 12 kHz sonar and 153 kHz ADCP backscatter data, which indicated that the strongly migrating layers were predominantly composed of fishes. Fish vertical migration speeds were independently estimated from the slopes of the volume scattering layers and from the vertical velocity components of the ADCP, yielding average speeds of 4 and 3 cm s-1 and maximum speeds of 13 and 10 cm s-1, respectively. A few migrating zooplankton layers were identified with an average speed of about 2 cm s-1 and maximum speeds as high as 8 cm s-1. Migration depths for both zooplankton and fish differed somewhat amongst stations and appeared to be related to local hydrographic conditions (principally the vertical gradients in DO and water temperature). Zooplankton displacement volumes at individual sites suggested that zooplankton biomass during the Southwest Monsoon could be as much as fivefold greater than during the Spring Intermonsoon. This observation was confirmed for the region in general by first deriving a relationship between ADCP backscatter intensity and daytime zooplankton biomass and then comparing the latter between cruises using daytime ADCP data taken along a 1500 km transect that extended from the coast of Somalia to the center of the northern basin.
Mincks,S.L.,Bollens,S.M.,Madin,L.P.,Horgan,E.,Butler,M.,Kremer,P.M.,Craddock,J.E.
Distribution, abundance, and feeding ecology of decapods in the Arabian Sea, with implications for vertical flux Journal Article
In: Deep-Sea Research Part II, vol. 47, no. 158, pp. 1475-1516, 2000.
Abstract | BibTeX | Tags: abundance, Arabian Sea, depth, Distribution, ecology, feeding ecology, migration, oxygen minimum, population, zooplankton
@article{,
title = {Distribution, abundance, and feeding ecology of decapods in the Arabian Sea, with implications for vertical flux},
author = {Mincks,S.L.,Bollens,S.M.,Madin,L.P.,Horgan,E.,Butler,M.,Kremer,P.M.,Craddock,J.E.},
year = {2000},
date = {2000-01-01},
journal = {Deep-Sea Research Part II},
volume = {47},
number = {158},
pages = {1475-1516},
abstract = {Macrozooplankton and micronekton samples were collected on two cruises in the Arabian Sea conducted during the Spring Intermonsoon period (May) and the SW Monsoon period (August) of 1995. Discrete depth samples were collected down to depths of 1000-1500 m. Quantitative gut content analyses were performed on four species of decapod shrimps, Gennadas sordidus, Sergia filictum, Sergia creber, and Eupasiphae gilesii, as well as on the pelagic crab Charybdis smithii. Of the shrimps, only S. filictum and S. creber increased significantly in abundance between the Spring Intermonsoon and SW Monsoon seasons. These four species were found at all depths sampled, and most did not appear to be strong vertical migrators. G. sordidus and S. filictum did appear to spread upward at night, especially during the SW Monsoon, but this movement did not include the entire population. S. creber showed signs of diel vertical migration only in some areas. All four shrimp species except, to some degree, S. creber lived almost exclusively within the oxygen minimum zone(150-1000 m), and are likely to have respiratory adaptations that allow them to persist under such conditions. Feeding occurred at all depths throughout these species' ranges, but only modest feeding occurred in the surface layer (0-150 m). G. sordidus appeared to feed continuously throughout the day and night. Estimated contribution of fecal material to vertical flux ranged from < 0.01-2.1% of particulate flux at 1000 m for the shrimps and 1.8-3.0% for C. smithii. (C) 2000 Published by Elsevier Science Ltd. All rights reserved. .},
keywords = {abundance, Arabian Sea, depth, Distribution, ecology, feeding ecology, migration, oxygen minimum, population, zooplankton},
pubstate = {published},
tppubtype = {article}
}
Macrozooplankton and micronekton samples were collected on two cruises in the Arabian Sea conducted during the Spring Intermonsoon period (May) and the SW Monsoon period (August) of 1995. Discrete depth samples were collected down to depths of 1000-1500 m. Quantitative gut content analyses were performed on four species of decapod shrimps, Gennadas sordidus, Sergia filictum, Sergia creber, and Eupasiphae gilesii, as well as on the pelagic crab Charybdis smithii. Of the shrimps, only S. filictum and S. creber increased significantly in abundance between the Spring Intermonsoon and SW Monsoon seasons. These four species were found at all depths sampled, and most did not appear to be strong vertical migrators. G. sordidus and S. filictum did appear to spread upward at night, especially during the SW Monsoon, but this movement did not include the entire population. S. creber showed signs of diel vertical migration only in some areas. All four shrimp species except, to some degree, S. creber lived almost exclusively within the oxygen minimum zone(150-1000 m), and are likely to have respiratory adaptations that allow them to persist under such conditions. Feeding occurred at all depths throughout these species' ranges, but only modest feeding occurred in the surface layer (0-150 m). G. sordidus appeared to feed continuously throughout the day and night. Estimated contribution of fecal material to vertical flux ranged from < 0.01-2.1% of particulate flux at 1000 m for the shrimps and 1.8-3.0% for C. smithii. (C) 2000 Published by Elsevier Science Ltd. All rights reserved. .
Corkeron,P.J.,Connor,R.C.
Why do baleen whales migrate? Journal Article
In: Marine Mammal Science, vol. 15, no. 76, pp. 1228-1245, 1999.
Abstract | BibTeX | Tags: abundance, Distribution, killer whale, killer whales, migration, mysticetes, Orca, predation
@article{,
title = {Why do baleen whales migrate?},
author = {Corkeron,P.J.,Connor,R.C.},
year = {1999},
date = {1999-01-01},
journal = {Marine Mammal Science},
volume = {15},
number = {76},
pages = {1228-1245},
abstract = {The annual migrations of baleen whales are a conspicuous, but unexplained feature of their behavioural repertoire. Some hypotheses offered to explain whale migration focus on direct benefits to the calf (thermoregulation, calm water) and some do not (resource tracking, and the "evolutionary holdover" hypothesis). Here we suggest that a major selective advantage to migrating pregnant female baleen whales is a reduced risk of killer whale predation on their newborn calves in low-latitude waters. Killer whale abundance in high latitudes is substantially greater than that in lower latitudes, and most killer whales do not appear to migrate with baleen whales. We suggest that the distribution of killer whales is determined more by their primary marine mammal prey, pinnipeds, and that following the baleen whale migrations would remove them from their pinnipeds prey. There are problems with all current hypotheses, most of which stem from a lack of directed research. We explore variation in migratory habits between species, populations, and individuals that may provide a "natural laboratory" for discriminating among the competing hypotheses. The authors specifically recommend more detailed study of non-migrating populations, such as the Arabian Sea population of humpback whales.},
keywords = {abundance, Distribution, killer whale, killer whales, migration, mysticetes, Orca, predation},
pubstate = {published},
tppubtype = {article}
}
The annual migrations of baleen whales are a conspicuous, but unexplained feature of their behavioural repertoire. Some hypotheses offered to explain whale migration focus on direct benefits to the calf (thermoregulation, calm water) and some do not (resource tracking, and the "evolutionary holdover" hypothesis). Here we suggest that a major selective advantage to migrating pregnant female baleen whales is a reduced risk of killer whale predation on their newborn calves in low-latitude waters. Killer whale abundance in high latitudes is substantially greater than that in lower latitudes, and most killer whales do not appear to migrate with baleen whales. We suggest that the distribution of killer whales is determined more by their primary marine mammal prey, pinnipeds, and that following the baleen whale migrations would remove them from their pinnipeds prey. There are problems with all current hypotheses, most of which stem from a lack of directed research. We explore variation in migratory habits between species, populations, and individuals that may provide a "natural laboratory" for discriminating among the competing hypotheses. The authors specifically recommend more detailed study of non-migrating populations, such as the Arabian Sea population of humpback whales.
Morrison,J.M.,Codispoti,L.A.,Smith,S.L.,Wishner,K.,Flagg,C.,Gardner,W.D.,Gaurin,S.,Naqvi,S.W.A.,Manghnani,V.,Prosperie,L.,Gundersen,J.S.
The oxygen minimum zone in the Arabian Sea during 1995 Journal Article
In: Deep-Sea Research Part II, vol. 46, no. 174, pp. 1903-1931, 1999.
Abstract | BibTeX | Tags: acoustic, Arabian Sea, density, depth, diel, Distribution, location, migrate, migration, occurrence, oxygen minimum, plankton, thermocline, zooplankton
@article{,
title = {The oxygen minimum zone in the Arabian Sea during 1995},
author = {Morrison,J.M.,Codispoti,L.A.,Smith,S.L.,Wishner,K.,Flagg,C.,Gardner,W.D.,Gaurin,S.,Naqvi,S.W.A.,Manghnani,V.,Prosperie,L.,Gundersen,J.S.},
year = {1999},
date = {1999-01-01},
journal = {Deep-Sea Research Part II},
volume = {46},
number = {174},
pages = {1903-1931},
abstract = {This paper focuses on the characteristics of the oxygen minimum zone (OMZ) as observed in the Arabian Sea over the complete monsoon cycle of 1995. Dissolved oxygen, nitrite, nitrate and density values are used to delineate the OMZ, as well as identify regions where denitrification is observed. The suboxic conditions within the northern Arabian Sea are documented, as well as biological and chemical consequences of this phenomenon. Overall, the conditions found in the suboxic portion of the water column in the Arabian Sea were not greatly different from what has been reported in the literature with respect to oxygen, nitrate and nitrite distributions. Within the main thermocline, portions of the OMZ were found that were suboxic (oxygen less than ~4.5 æM) and contained secondary nitrite maxima with concentrations that sometimes exceeded 6.0 æM, suggesting active nitrate reduction and denitrification. Although there may have been a reduction in the degree of suboxia during the Southwest monsoon, a dramatic seasonality was not observed, as has been suggested by some previous work. In particular, there was not much evidence for the occurrence of secondary nitrite maxima in waters with oxygen concentrations greater than 4.5 æM. Waters in the northern Arabian Sea appear to accumulate larger nitrate deficits due to longer residence times even though the denitrification rate might be lower, as evident in the reduced nitrite concentrations in the northern part of the basin. Organism distributions showed string relationships to the oxygen profiles, especially in locations where the OMZ was pronounced, but the biological responses to the OMZ varied with type of organism. The regional extent of intermediate nepheloid layers in our data corresponds well with the region of the secondary nitrite maximum. This is a region of denitrification, and the presence and activities of bacteria are assumed to cause the increase in particles. ADCP acoustic backscatter measurements show diel vertical migration of plankton or nekton and movement into the OMZ. Daytime acoustic returns from depth were strong, and the dawn sinking and dusk rise of the fauna were obvious. However, at night the biomass remaining in the suboxic zone was so low that no ADCP signal was detectable at these depths. There are at least two groups of organisms, one that stays in the upper mixed layer and another that makes daily excursions. A subsurface zooplankton peak in the lower OMZ (near the lower 4.5 æM oxycline) was also typically present; these animals occurred day and night and did not vertically migrate.},
keywords = {acoustic, Arabian Sea, density, depth, diel, Distribution, location, migrate, migration, occurrence, oxygen minimum, plankton, thermocline, zooplankton},
pubstate = {published},
tppubtype = {article}
}
This paper focuses on the characteristics of the oxygen minimum zone (OMZ) as observed in the Arabian Sea over the complete monsoon cycle of 1995. Dissolved oxygen, nitrite, nitrate and density values are used to delineate the OMZ, as well as identify regions where denitrification is observed. The suboxic conditions within the northern Arabian Sea are documented, as well as biological and chemical consequences of this phenomenon. Overall, the conditions found in the suboxic portion of the water column in the Arabian Sea were not greatly different from what has been reported in the literature with respect to oxygen, nitrate and nitrite distributions. Within the main thermocline, portions of the OMZ were found that were suboxic (oxygen less than ~4.5 æM) and contained secondary nitrite maxima with concentrations that sometimes exceeded 6.0 æM, suggesting active nitrate reduction and denitrification. Although there may have been a reduction in the degree of suboxia during the Southwest monsoon, a dramatic seasonality was not observed, as has been suggested by some previous work. In particular, there was not much evidence for the occurrence of secondary nitrite maxima in waters with oxygen concentrations greater than 4.5 æM. Waters in the northern Arabian Sea appear to accumulate larger nitrate deficits due to longer residence times even though the denitrification rate might be lower, as evident in the reduced nitrite concentrations in the northern part of the basin. Organism distributions showed string relationships to the oxygen profiles, especially in locations where the OMZ was pronounced, but the biological responses to the OMZ varied with type of organism. The regional extent of intermediate nepheloid layers in our data corresponds well with the region of the secondary nitrite maximum. This is a region of denitrification, and the presence and activities of bacteria are assumed to cause the increase in particles. ADCP acoustic backscatter measurements show diel vertical migration of plankton or nekton and movement into the OMZ. Daytime acoustic returns from depth were strong, and the dawn sinking and dusk rise of the fauna were obvious. However, at night the biomass remaining in the suboxic zone was so low that no ADCP signal was detectable at these depths. There are at least two groups of organisms, one that stays in the upper mixed layer and another that makes daily excursions. A subsurface zooplankton peak in the lower OMZ (near the lower 4.5 æM oxycline) was also typically present; these animals occurred day and night and did not vertically migrate.
Baldwin,R.,Van Waerebeek,K.,Gallagher,M.
A review of small cetaceans from waters off the Arabian Peninsula Technical Report
no. 27, 1998.
Abstract | BibTeX | Tags: abundance, cetacean, cetaceans, Distribution, ecology, migration, Movements, status, Stock identity, whaling
@techreport{,
title = {A review of small cetaceans from waters off the Arabian Peninsula},
author = {Baldwin,R.,Van Waerebeek,K.,Gallagher,M.},
year = {1998},
date = {1998-01-01},
journal = {Document presented at the 50th meeting of the Scientific Committee of the International Whaling Commission},
volume = {SC/50/SM6},
number = {27},
pages = {1-26},
abstract = {Available data on small cetacean species in coastal and offshore waters off peninsula Arabia are reviewed. Species accounts are presented for a total of 16 small cetaceans, including information on the date and source of first records in the region, distribution, stock identity, abundance, external appearance, migrations or local movements, status, incidental takes, directed catches and other threats, ecology, life history and disease/parasites. In addition the origin and present location of all curated specimens are listed. Anecdotal information, such as that obtained from local fishermen and other observers, is also presented.},
keywords = {abundance, cetacean, cetaceans, Distribution, ecology, migration, Movements, status, Stock identity, whaling},
pubstate = {published},
tppubtype = {techreport}
}
Available data on small cetacean species in coastal and offshore waters off peninsula Arabia are reviewed. Species accounts are presented for a total of 16 small cetaceans, including information on the date and source of first records in the region, distribution, stock identity, abundance, external appearance, migrations or local movements, status, incidental takes, directed catches and other threats, ecology, life history and disease/parasites. In addition the origin and present location of all curated specimens are listed. Anecdotal information, such as that obtained from local fishermen and other observers, is also presented.
Smith,S.,Roman,M.,Prusova,I.,Wishner,K.,Gowing,M.,Codispoti,L.A.,Barber,R.,Marra,J.,Flagg,C.
Seasonal response of zooplankton to monsoonal reversals in the Arabian Sea Journal Article
In: Deep-Sea Research Part II, vol. 45, no. 478, pp. 2369-2403, 1998.
Abstract | BibTeX | Tags: Arabian Sea, Distribution, migration, predation, Upwelling, zooplankton
@article{,
title = {Seasonal response of zooplankton to monsoonal reversals in the Arabian Sea},
author = {Smith,S.,Roman,M.,Prusova,I.,Wishner,K.,Gowing,M.,Codispoti,L.A.,Barber,R.,Marra,J.,Flagg,C.},
year = {1998},
date = {1998-01-01},
journal = {Deep-Sea Research Part II},
volume = {45},
number = {478},
pages = {2369-2403},
abstract = {The US JGOFS Arabian Sea Process Study was designed to provide a seasonally and spatially resolved carbon budget for a basin exhibiting some of the highest and lowest concentrations of plant biomass in the world's ocean. During the US JGOFS Process Study in the Arabian Sea (September 1994-January 1996), the absolute maximum in biomass of epipelagic zooplankton in the entire study was observed during the Southwest Monsoon season inshore of the Findlater Jet in the area of upwelling. The greatest contrast between high and low biomass in the study area also was observed during the Southwest Monsoon, as was the strongest onshore-offshore gradient in biomass. Lowest biomass throughout the study was observed at the most offshore station (SI5), outside the direct influence of the monsoon forcing. The greatest day/night contrastsing biomass were observed nearshore in all seasons, with nighttime biornass-exceeding daytime in the Northeast Monsoon season, but daytime exceeding nighttime in the Southwest Monsoon season. The diel vertical migration patterns in general reversed between the monsoons at all stations in the southern part of the study area. Virtually, no diel vertical migration of zooplankton took place in any season at the station with strong, persistent subsurface suboxic conditions (N7), suggesting that these conditions suppress migration. Based on the distribution of biomass, we hypothesize that inshore of the Findlater Jet, zooplankton grazing on phytoplankton is the dominant pathway of carbon transformation during both monsoon seasons, whereas offshore the zooplankton feed primarily on microplankton or are carnivorous, conditions that result in reduction of the carbon flux mediated by the zooplankton. Predation by mesopelagic fish., primarily myctophids, may equal daily growth of zooplankton inshore of the Findlater Jet during all seasons. This suggests that the food web inshore of the Findlater Jet is well integrated, may have evolved during past periods of intensified upwelling, and has a distinctly annual cycle. (C) 1998 Elsevier Science Ltd. All rights reserved.},
keywords = {Arabian Sea, Distribution, migration, predation, Upwelling, zooplankton},
pubstate = {published},
tppubtype = {article}
}
The US JGOFS Arabian Sea Process Study was designed to provide a seasonally and spatially resolved carbon budget for a basin exhibiting some of the highest and lowest concentrations of plant biomass in the world's ocean. During the US JGOFS Process Study in the Arabian Sea (September 1994-January 1996), the absolute maximum in biomass of epipelagic zooplankton in the entire study was observed during the Southwest Monsoon season inshore of the Findlater Jet in the area of upwelling. The greatest contrast between high and low biomass in the study area also was observed during the Southwest Monsoon, as was the strongest onshore-offshore gradient in biomass. Lowest biomass throughout the study was observed at the most offshore station (SI5), outside the direct influence of the monsoon forcing. The greatest day/night contrastsing biomass were observed nearshore in all seasons, with nighttime biornass-exceeding daytime in the Northeast Monsoon season, but daytime exceeding nighttime in the Southwest Monsoon season. The diel vertical migration patterns in general reversed between the monsoons at all stations in the southern part of the study area. Virtually, no diel vertical migration of zooplankton took place in any season at the station with strong, persistent subsurface suboxic conditions (N7), suggesting that these conditions suppress migration. Based on the distribution of biomass, we hypothesize that inshore of the Findlater Jet, zooplankton grazing on phytoplankton is the dominant pathway of carbon transformation during both monsoon seasons, whereas offshore the zooplankton feed primarily on microplankton or are carnivorous, conditions that result in reduction of the carbon flux mediated by the zooplankton. Predation by mesopelagic fish., primarily myctophids, may equal daily growth of zooplankton inshore of the Findlater Jet during all seasons. This suggests that the food web inshore of the Findlater Jet is well integrated, may have evolved during past periods of intensified upwelling, and has a distinctly annual cycle. (C) 1998 Elsevier Science Ltd. All rights reserved.
IUCN
Cetaceans and cetacean research in the Indian Ocean Sanctuary Book Chapter
In: no. 391, pp. 1-287, UNEP, 1991.
BibTeX | Tags: Antarctic, cetacean, cetaceans, Humpback Whale, humpback whales, Indian Ocean, marine, marine mammal, megaptera novaeangliae, migration, Oman, Pacific Ocean, sanctuaries, Southern Hemisphere, stocks, Upwelling, whale, whales, whaling
@inbook{,
title = {Cetaceans and cetacean research in the Indian Ocean Sanctuary},
author = {IUCN},
year = {1991},
date = {1991-01-01},
journal = {UNEP marine Mammal Technical Report number 3},
number = {391},
pages = {1-287},
publisher = {UNEP},
keywords = {Antarctic, cetacean, cetaceans, Humpback Whale, humpback whales, Indian Ocean, marine, marine mammal, megaptera novaeangliae, migration, Oman, Pacific Ocean, sanctuaries, Southern Hemisphere, stocks, Upwelling, whale, whales, whaling},
pubstate = {published},
tppubtype = {inbook}
}
Leatherwood, S.,Donovan, G.P.
Cetaceans and cetacean research in the Indian Ocean Sanctuary Book Chapter
In: no. 397, pp. 1-287, UNEP, 1991.
BibTeX | Tags: Antarctic, cetacean, cetaceans, Humpback Whale, humpback whales, Indian Ocean, marine, marine mammal, megaptera novaeangliae, migration, Oman, Pacific Ocean, sanctuaries, Southern Hemisphere, stocks, Upwelling, whale, whales, whaling
@inbook{,
title = {Cetaceans and cetacean research in the Indian Ocean Sanctuary},
author = {Leatherwood, S.,Donovan, G.P.},
year = {1991},
date = {1991-01-01},
journal = {UNEP marine Mammal Technical Report number 3},
number = {397},
pages = {1-287},
publisher = {UNEP},
keywords = {Antarctic, cetacean, cetaceans, Humpback Whale, humpback whales, Indian Ocean, marine, marine mammal, megaptera novaeangliae, migration, Oman, Pacific Ocean, sanctuaries, Southern Hemisphere, stocks, Upwelling, whale, whales, whaling},
pubstate = {published},
tppubtype = {inbook}
}
Reeves,R.R.,Leatherwood,S.,Papastavrou,V.
Possible stock affinities of humpback whales in the northern Indian Ocean Book
UNEP, 1991.
Abstract | BibTeX | Tags: Antarctic, cetacean, cetaceans, Humpback Whale, humpback whales, Indian Ocean, marine, marine mammal, megaptera novaeangliae, migration, Oman, Pacific Ocean, sanctuaries, Southern Hemisphere, stocks, Upwelling, whale, whales, whaling
@book{,
title = {Possible stock affinities of humpback whales in the northern Indian Ocean},
author = {Reeves,R.R.,Leatherwood,S.,Papastavrou,V.},
year = {1991},
date = {1991-01-01},
journal = {Cetaceans and Cetacean Research in the Indian Ocean Sanctuary: Marine Mammal Technical Report Number 3},
number = {443},
pages = {259-269},
publisher = {UNEP},
abstract = {Records of humpback whales. Megaptera novaeangliae. in the northern Indian Ocean are compiled and evaluated to test various hypotheses concerning stock relationships. The conventional view that all humpbacks in this region are migrants from the Southern Hemisphere or, less likely, from the Pacific Ocean has been challenged recently by other authors. There is no reason to doubt that some Antarctic humpbacks cross the. Equator during their winter breeding migration northward. However, sightings in the northern Indian Ocean during the austral spring, summer and fall arc sufficiently frequent and widespread to support the hypothesis that some whales remain north of the Equator in the Indian Ocean year-round. Humpbacks appear to be present off Oman throughout the year, including relatively large concentrations, apparently feeding, during boreal summer/fall. We postulate that areas of cool, highly productive upwelling near the coast of Oman create conditions suitable for humpback feeding. The northern Indian Ocean is characterised by a virtual absence of modern commercial whaling and a paucity of cetacean research. As a result. evidence is insufficient to determine the relationships between stocks of humpbacks in the northern Indian Ocean and stocks of humpbacks elsewhere.},
keywords = {Antarctic, cetacean, cetaceans, Humpback Whale, humpback whales, Indian Ocean, marine, marine mammal, megaptera novaeangliae, migration, Oman, Pacific Ocean, sanctuaries, Southern Hemisphere, stocks, Upwelling, whale, whales, whaling},
pubstate = {published},
tppubtype = {book}
}
Records of humpback whales. Megaptera novaeangliae. in the northern Indian Ocean are compiled and evaluated to test various hypotheses concerning stock relationships. The conventional view that all humpbacks in this region are migrants from the Southern Hemisphere or, less likely, from the Pacific Ocean has been challenged recently by other authors. There is no reason to doubt that some Antarctic humpbacks cross the. Equator during their winter breeding migration northward. However, sightings in the northern Indian Ocean during the austral spring, summer and fall arc sufficiently frequent and widespread to support the hypothesis that some whales remain north of the Equator in the Indian Ocean year-round. Humpbacks appear to be present off Oman throughout the year, including relatively large concentrations, apparently feeding, during boreal summer/fall. We postulate that areas of cool, highly productive upwelling near the coast of Oman create conditions suitable for humpback feeding. The northern Indian Ocean is characterised by a virtual absence of modern commercial whaling and a paucity of cetacean research. As a result. evidence is insufficient to determine the relationships between stocks of humpbacks in the northern Indian Ocean and stocks of humpbacks elsewhere.
Small,J.A..,Small,G.J.
Cetacean observations from the Somali Democratic Republic, September 1985 through May 1987 Journal Article
In: CEtaceans and Cetacean Research in the Indian Ocean Sanctuary: UNEP - Marine Mammal Technical Report No.3, no. 476, pp. 179-210, 1991.
Abstract | BibTeX | Tags: Antarctic, Blue whale, bottlenose dolphin, Bryde's whale, cetacean, cetaceans, Common dolphin, dolphin, false killer whale, Gulf of Aden, Humpback Whale, humpback whales, Indian Ocean, killer whale, location, marine, megaptera novaeangliae, melon-headed whale, migration, occurrence, Oman, Pacific Ocean, Risso's dolphin, sanctuaries, Southern Hemisphere, sperm whale, Spinner dolphin, spotted dolphin, stocks, Striped dolphin, survey, trend, Upwelling, whale, whales, whaling
@article{,
title = {Cetacean observations from the Somali Democratic Republic, September 1985 through May 1987},
author = {Small,J.A..,Small,G.J.},
year = {1991},
date = {1991-01-01},
journal = {CEtaceans and Cetacean Research in the Indian Ocean Sanctuary: UNEP - Marine Mammal Technical Report No.3},
number = {476},
pages = {179-210},
abstract = {Two vessels operated along the Gulf of Aden and northern Indian Ocean coasts of Somalia from Aug. 1985 through May 1987. Their fishing activities carried them on a routine basis from Djibouti to the Horn of Africa and, on many cruises, into the Indian Ocean as far south as 8øN. The frequent and regular presence of these vessels afforded a unique opportunity for research since few previous surveys along the Somalian coast were transitory and/or of short duration. There were 398 sightings of cetaceans representing at least 14 species: blue whale, Bryde's whale, sperm whale, melon-headed whale, false killer whale, killer whale, short-finned pilot whale, Indo-Pacific humpback dolphin, common dolphin, bottlenose dolphin, Risso's dolphin, spotted dolphin, striped dolphin and spinner dolphin (NO humpback whales!!). Sightings locations and related environmental data are discussed. Some trends between years were seen in the occurrence and location of blue, killer and short-finned pilot whales.},
keywords = {Antarctic, Blue whale, bottlenose dolphin, Bryde's whale, cetacean, cetaceans, Common dolphin, dolphin, false killer whale, Gulf of Aden, Humpback Whale, humpback whales, Indian Ocean, killer whale, location, marine, megaptera novaeangliae, melon-headed whale, migration, occurrence, Oman, Pacific Ocean, Risso's dolphin, sanctuaries, Southern Hemisphere, sperm whale, Spinner dolphin, spotted dolphin, stocks, Striped dolphin, survey, trend, Upwelling, whale, whales, whaling},
pubstate = {published},
tppubtype = {article}
}
Two vessels operated along the Gulf of Aden and northern Indian Ocean coasts of Somalia from Aug. 1985 through May 1987. Their fishing activities carried them on a routine basis from Djibouti to the Horn of Africa and, on many cruises, into the Indian Ocean as far south as 8øN. The frequent and regular presence of these vessels afforded a unique opportunity for research since few previous surveys along the Somalian coast were transitory and/or of short duration. There were 398 sightings of cetaceans representing at least 14 species: blue whale, Bryde's whale, sperm whale, melon-headed whale, false killer whale, killer whale, short-finned pilot whale, Indo-Pacific humpback dolphin, common dolphin, bottlenose dolphin, Risso's dolphin, spotted dolphin, striped dolphin and spinner dolphin (NO humpback whales!!). Sightings locations and related environmental data are discussed. Some trends between years were seen in the occurrence and location of blue, killer and short-finned pilot whales.
De Silva,P.H.D.H..
Cetaceans (whales, dolphins and porpoises) recorded off Sri Lanka, India, from the Arabian Sea and Gulf, Gulf of Aden and from the Red Sea Journal Article
In: Journal of the Bombay Natural History Society, vol. 84 , no. 357, pp. 505-525, 1987.
Abstract | BibTeX | Tags: Antarctic, Arabia, Arabian Gulf, Arabian Sea, behaviour, Blue whale, cetacea, cetacean, cetaceans, Delphinus tropicalis, dolphin, dolphins, fin whale, Gulf of Aden, Gulf of Oman, Humpback Whale, India, Indian Ocean, mammals, marine, migration, Neophocaena phocaenoides, Oceanic, Oman, Pakistan, Porpoise, Red Sea, sanctuaries, skull, Sri Lanka, stranding, Strandings, survey, whale, whales
@article{,
title = {Cetaceans (whales, dolphins and porpoises) recorded off Sri Lanka, India, from the Arabian Sea and Gulf, Gulf of Aden and from the Red Sea },
author = {De Silva,P.H.D.H..},
year = {1987},
date = {1987-01-01},
journal = {Journal of the Bombay Natural History Society},
volume = {84 },
number = {357},
pages = {505-525},
abstract = {Cetacea is a highly specialized oceanic group of mammals with several of its species undertaking long migrations, often exceeding thousand miles during a single journey. During these migrations from cold polar and subpolar seas to warmer tropical and subtropical waters and their return to polar seas in summer both individual and mass strandings have very often occurred in many parts of the world, including Sri Lanka, India and the Arabian Gulf. The Cetacean records dealt with in this paper are of countries which lie at the extreme southern margin of the vast land mass of Asia with no land other than a few islands and vast stretches of the Indian Ocean between them and the Antarctica. Sri Lanka, in view of her geographic position at the southern extremity of this vast land mass (5ø 55' and 9§51'N latitude and 79§41' and 81§ 54' E longitude) has become a passing point in the movement of oceanic species including the larger whales. It has been suggested by Deraniyagala (1945, 1960b) that the movement of larger species towards the tropics from the southern temperate zone is partly associated with the periodic influx of Antarctic water toward the tropics. It is however, now fairly established that several larger species such as the Blue whale, the Fin whale and the Humpback whale show a regular migratory cycle. The majority of strandings recorded in this paper deal with individual strandings. Nevertheless there have been instances of both mass stranding and of apparent suicidal behaviour. This paper deals with 30 Cetacean species from the region. Of these records, records from Sri Lanka total 23 species, from India 24 species, from Pakistan 17 species, from the Gulf of Oman 10 species, from the Arabian Gulf 9 species, from the Gulf of Aden 6 species and from the Red Sea 7 species. Reference is also made to a skull of Delphinus tropicalis van Bree in the Colombo Museum (Skull No. 15 B) which appears to be its first record from Sri Lanka. Mention is also made of a specimen of Neophocaena phocaenoides (G. Cuvier) collected from the Wadge Bank by the Smithsonian Carangid Survey Team in March 1970 and of two incomplete skeletons of Balaenoptera physalus (Linn‚) (probably mother and calf) in the Zoological Museum, King Saud University, Riyadh, Saudi Arabia. All these specimens were identified by me. It is evident from this study that our present knowledge of the Cetacean fauna of the Indian Ocean is far from complete and that much could be accomplished by scientific institutions in the countries in the region by diligently maintaining proper records of sightings and strandings (with photographs) and by undertaking joint study surveys. It is gratifying to note that Sri Lanka, in recent years has been making much headway in this regard. During the last few years the Tulip Expedition led by Dr. Hal Whitehead has been studying the larger whales, especially the larger whales off the east coast and Dr. Stephen Leatherwood Of Hubbs-Sea World Research Institute (Marine Science), San Diego, California has recently published (1985) a summary of available information on the Cetacea of the Indian Ocean Cetacean Sanctuary on behalf of the National Aquatic Resources Agency for Sri Lanka. It is hoped that the present paper will further stimulate interest among the scientific institutions in the region and help to increase our knowledge of a group of remarkable animals at least as far as the species which inhabit and visit our seas.has become a passing point in the movement of oceanic species including the larger whales. It has been suggested by Deraniyagala (1945, 1960b) that the movement of larger species towards the tropics from the southern temperate zone is partly associated with the periodic influx of Antarctic water toward the tropics. It is however, now fairly established that several larger species such as the Blue whale, the Fin whale and the Humpback whale show a regular migratory cycle. The majority of strandings recorded in this paper deal with individual strandings. Nevertheless there have been instances of both mass stranding and of apparent suicidal behaviour. This paper deals with 30 Cetacean species from the region. Of these records, records from Sri Lanka total 23 species, from India 24 species, from Pakistan 17 species, from the Gulf of Oman 10 species, from the Arabian Gulf 9 species, from the Gulf of Aden 6 species and from the Red Sea 7 species. Reference is also made to a skull of Delphinus tropicalis van Bree in the Colombo Museum (Skull No. 15 B) which appears to be its first record from Sri Lanka. Mention is also made of a specimen of Neophocaena phocaenoides (G. Cuvier) collected from the Wadge Bank by the Smithsonian Carangid Survey Team in March 1970 and of two incomplete skeletons of Balaenoptera physalus (Linn‚) (probably mother and calf) in the Zoological Museum, King Saud University, Riyadh, Saudi Arabia. All these specimens were identified by me. It is evident from this study that our present knowledge of the Cetacean fauna of the Indian Ocean is far from complete and that much could be accomplished by scientific institutions in the countries in the region by diligently maintaining proper records of sightings and strandings (with photographs) and by undertaking joint study surveys. It is gratifying to note that Sri Lanka, in recent years has been making much headway in this regard. During the last few years the Tulip Expedition led by Dr. Hal Whitehead has been studying the larger whales, especially the larger whales off the east coast and Dr. Stephen Leatherwood Of Hubbs-Sea World Research Institute (Marine Science), San Diego, California has recently published (1985) a summary of available information on the Cetacea of the Indian Ocean Cetacean Sanctuary on behalf of the National Aquatic Resources Agency for Sri Lanka. It is hoped that the present paper will further stimulate interest among the scientific institutions in the region and help to increase our knowledge of a group of remarkable animals at least as far as the species which inhabit and visit our seas. A key to the identification of the species recorded from the region is given in Appendix. },
keywords = {Antarctic, Arabia, Arabian Gulf, Arabian Sea, behaviour, Blue whale, cetacea, cetacean, cetaceans, Delphinus tropicalis, dolphin, dolphins, fin whale, Gulf of Aden, Gulf of Oman, Humpback Whale, India, Indian Ocean, mammals, marine, migration, Neophocaena phocaenoides, Oceanic, Oman, Pakistan, Porpoise, Red Sea, sanctuaries, skull, Sri Lanka, stranding, Strandings, survey, whale, whales},
pubstate = {published},
tppubtype = {article}
}
Cetacea is a highly specialized oceanic group of mammals with several of its species undertaking long migrations, often exceeding thousand miles during a single journey. During these migrations from cold polar and subpolar seas to warmer tropical and subtropical waters and their return to polar seas in summer both individual and mass strandings have very often occurred in many parts of the world, including Sri Lanka, India and the Arabian Gulf. The Cetacean records dealt with in this paper are of countries which lie at the extreme southern margin of the vast land mass of Asia with no land other than a few islands and vast stretches of the Indian Ocean between them and the Antarctica. Sri Lanka, in view of her geographic position at the southern extremity of this vast land mass (5ø 55' and 9§51'N latitude and 79§41' and 81§ 54' E longitude) has become a passing point in the movement of oceanic species including the larger whales. It has been suggested by Deraniyagala (1945, 1960b) that the movement of larger species towards the tropics from the southern temperate zone is partly associated with the periodic influx of Antarctic water toward the tropics. It is however, now fairly established that several larger species such as the Blue whale, the Fin whale and the Humpback whale show a regular migratory cycle. The majority of strandings recorded in this paper deal with individual strandings. Nevertheless there have been instances of both mass stranding and of apparent suicidal behaviour. This paper deals with 30 Cetacean species from the region. Of these records, records from Sri Lanka total 23 species, from India 24 species, from Pakistan 17 species, from the Gulf of Oman 10 species, from the Arabian Gulf 9 species, from the Gulf of Aden 6 species and from the Red Sea 7 species. Reference is also made to a skull of Delphinus tropicalis van Bree in the Colombo Museum (Skull No. 15 B) which appears to be its first record from Sri Lanka. Mention is also made of a specimen of Neophocaena phocaenoides (G. Cuvier) collected from the Wadge Bank by the Smithsonian Carangid Survey Team in March 1970 and of two incomplete skeletons of Balaenoptera physalus (Linn‚) (probably mother and calf) in the Zoological Museum, King Saud University, Riyadh, Saudi Arabia. All these specimens were identified by me. It is evident from this study that our present knowledge of the Cetacean fauna of the Indian Ocean is far from complete and that much could be accomplished by scientific institutions in the countries in the region by diligently maintaining proper records of sightings and strandings (with photographs) and by undertaking joint study surveys. It is gratifying to note that Sri Lanka, in recent years has been making much headway in this regard. During the last few years the Tulip Expedition led by Dr. Hal Whitehead has been studying the larger whales, especially the larger whales off the east coast and Dr. Stephen Leatherwood Of Hubbs-Sea World Research Institute (Marine Science), San Diego, California has recently published (1985) a summary of available information on the Cetacea of the Indian Ocean Cetacean Sanctuary on behalf of the National Aquatic Resources Agency for Sri Lanka. It is hoped that the present paper will further stimulate interest among the scientific institutions in the region and help to increase our knowledge of a group of remarkable animals at least as far as the species which inhabit and visit our seas.has become a passing point in the movement of oceanic species including the larger whales. It has been suggested by Deraniyagala (1945, 1960b) that the movement of larger species towards the tropics from the southern temperate zone is partly associated with the periodic influx of Antarctic water toward the tropics. It is however, now fairly established that several larger species such as the Blue whale, the Fin whale and the Humpback whale show a regular migratory cycle. The majority of strandings recorded in this paper deal with individual strandings. Nevertheless there have been instances of both mass stranding and of apparent suicidal behaviour. This paper deals with 30 Cetacean species from the region. Of these records, records from Sri Lanka total 23 species, from India 24 species, from Pakistan 17 species, from the Gulf of Oman 10 species, from the Arabian Gulf 9 species, from the Gulf of Aden 6 species and from the Red Sea 7 species. Reference is also made to a skull of Delphinus tropicalis van Bree in the Colombo Museum (Skull No. 15 B) which appears to be its first record from Sri Lanka. Mention is also made of a specimen of Neophocaena phocaenoides (G. Cuvier) collected from the Wadge Bank by the Smithsonian Carangid Survey Team in March 1970 and of two incomplete skeletons of Balaenoptera physalus (Linn‚) (probably mother and calf) in the Zoological Museum, King Saud University, Riyadh, Saudi Arabia. All these specimens were identified by me. It is evident from this study that our present knowledge of the Cetacean fauna of the Indian Ocean is far from complete and that much could be accomplished by scientific institutions in the countries in the region by diligently maintaining proper records of sightings and strandings (with photographs) and by undertaking joint study surveys. It is gratifying to note that Sri Lanka, in recent years has been making much headway in this regard. During the last few years the Tulip Expedition led by Dr. Hal Whitehead has been studying the larger whales, especially the larger whales off the east coast and Dr. Stephen Leatherwood Of Hubbs-Sea World Research Institute (Marine Science), San Diego, California has recently published (1985) a summary of available information on the Cetacea of the Indian Ocean Cetacean Sanctuary on behalf of the National Aquatic Resources Agency for Sri Lanka. It is hoped that the present paper will further stimulate interest among the scientific institutions in the region and help to increase our knowledge of a group of remarkable animals at least as far as the species which inhabit and visit our seas. A key to the identification of the species recorded from the region is given in Appendix.
Ponomareva,L.A.
Euphausiids of the Indian Ocean and the Red Sea (original title Ehvfauziidy Indijskogo okeana I krasnogo morya) Journal Article
In: Nauka, vol. 1, no. 197, 1975.
Abstract | BibTeX | Tags: Arabian Sea, biology, Distribution, Euphausiid, feeding, Indian Ocean, migration, plankton, Red Sea, zooplankton
@article{,
title = {Euphausiids of the Indian Ocean and the Red Sea (original title Ehvfauziidy Indijskogo okeana I krasnogo morya)},
author = {Ponomareva,L.A.},
year = {1975},
date = {1975-01-01},
journal = {Nauka},
volume = {1},
number = {197},
abstract = {The study is mainly based on euphausiid material from 2390 plankton samples collected in the Indian Ocean during Oct-March 1959/60 and 1960/61. Data are presented on the sp composition, biology, vertical and quantitative distribution. The northern Indian Ocean (as far south as 40 degree S) is inhabited by typically tropical euphausiid fauna. The area most rich in euphausiids is the Arabian Sea. The spp most commonly occurring in the 0-200m layer in the Indian Ocean are Euphausia diomedeae, E. distinguenda, Stylocheiron carinatum and Thysanopoda tricuspidata. In the northern Indian Ocean eggs an early larval stages occurred from Jan to June (no observations were made later in the yr), which suggests that euphausiids spawn several times during the yr. The eggs develop very rapidly (within <24h) and so do early larval stages. On reaching the nauplius-2 stage the development slows down and it takes the larva 10-12 days to develop into furcilia-1. The feeding is varied and mixed: none of the spp were observed to feed on phyto- or zooplankton exclusively. Migratory spp show diurnal feeding rhythms. Most of the spp occurring in the upper layers ( down to 500m) are distinct migrants; interzonal spp do not perform significant migrations rarely rising close to the surface and almost never occurring above 50-40m. The Red Sea is inhabited by immigrants from teh Gulf of Aden and by some endemic spp. The spp abundant in the Arabian Sea are also predominant here with the addition of S. affine. },
keywords = {Arabian Sea, biology, Distribution, Euphausiid, feeding, Indian Ocean, migration, plankton, Red Sea, zooplankton},
pubstate = {published},
tppubtype = {article}
}
The study is mainly based on euphausiid material from 2390 plankton samples collected in the Indian Ocean during Oct-March 1959/60 and 1960/61. Data are presented on the sp composition, biology, vertical and quantitative distribution. The northern Indian Ocean (as far south as 40 degree S) is inhabited by typically tropical euphausiid fauna. The area most rich in euphausiids is the Arabian Sea. The spp most commonly occurring in the 0-200m layer in the Indian Ocean are Euphausia diomedeae, E. distinguenda, Stylocheiron carinatum and Thysanopoda tricuspidata. In the northern Indian Ocean eggs an early larval stages occurred from Jan to June (no observations were made later in the yr), which suggests that euphausiids spawn several times during the yr. The eggs develop very rapidly (within <24h) and so do early larval stages. On reaching the nauplius-2 stage the development slows down and it takes the larva 10-12 days to develop into furcilia-1. The feeding is varied and mixed: none of the spp were observed to feed on phyto- or zooplankton exclusively. Migratory spp show diurnal feeding rhythms. Most of the spp occurring in the upper layers ( down to 500m) are distinct migrants; interzonal spp do not perform significant migrations rarely rising close to the surface and almost never occurring above 50-40m. The Red Sea is inhabited by immigrants from teh Gulf of Aden and by some endemic spp. The spp abundant in the Arabian Sea are also predominant here with the addition of S. affine.
Slijper,E.J.,Van Utrecht,W.L.,Naaktgeboren,C.
Remarks on the distribution and migration of whales Journal Article
In: Bijdragen tot de Dierkunde, vol. 34, no. 475, pp. 4-86, 1964.
Abstract | BibTeX | Tags: Arabian Gulf, Arabian Sea, Atlantic, density, Distribution, fin whale, Gulf of Aden, Humpback Whale, humpback whales, India, Indian Ocean, Maldives, migration, minke whale, minke whales, North Pacific, Oman, Pakistan, productivity, right whale, right whales, Southern Hemisphere, sperm whale, sperm whales, Strandings, whale, whales
@article{,
title = {Remarks on the distribution and migration of whales},
author = {Slijper,E.J.,Van Utrecht,W.L.,Naaktgeboren,C.},
year = {1964},
date = {1964-01-01},
journal = {Bijdragen tot de Dierkunde},
volume = {34},
number = {475},
pages = {4-86},
abstract = {The authors gained the cooperation of the Netherlands Association of Ship Owners and the Royal Netherlands Navy in a project to collect all whale sightings from vessels sailing around the globe between 1954 and 1957. A total of 4500 reports of 11,000 animals were received, with the majority of observations coming from the Atlantic and Indian Oceans. Vessels were given identification guides and all reported observations were scored on the perceived reliability of the identification. All Rorqual whales were grouped together, and a further distinction was made between humpback, sperm, right whales and "little piked whales" (minke whales). Sightings were plotted in 10 degree squares according to number of whales observed per 1000 hours steamed in daylight. Special attention is given to the observations of Captain W.F.J. Morzer Bruins, who the authors describe as a keen naturalist whose observations hold more credibility than those of others. His observations in the Indian Ocean include a high number of sperm whales off the southern coast of Oman and the Gulf of Aden in January-March and April-June, a scattering of stranded blue and fin whales along the W coast of India, and only 2 stranded and 2 live humpback whales (strandings both in India, and live sightings near Yemen/Oman border? and off S tip of India (near Maldives?). The larger number of compiled sightings from vessels are presented by species. Rorqual sightings were plentiful in the Gulf of Aden, Arabian Sea coasts of Oman and Pakistan, and in the Arabian Gulf (but not as plentiful as they were in the area between 30 and 40 degrees S. The author concludes that the majority of the whales observed in the NIO do not belong to the Southern Hemisphere stock, but suggests that they migrate from the North Pacific through the Indonesian Archipelago and the Strait Malaya (despite very few observations here). He briefly considers, but discards as unlikely, the hypothesis of a resident NIO stock.The total number of humpback whale sightings in the IO amounted to 500 (compared to 1618 rorqual sightings and 799 "whale" sightings). The majority of animals were observed in coastal waters, and NIO sightings were generally concentrated in the months of Aug-Nov and Jan-April. some of the highest recorded densities in the NIO are off of Pakistan in the months of March, Aug, Oct, and December, but it is not clear how closely related this is to observer effort. Observations are very few in May, June, July and September, and the authors do not link this to the monsoon -but rather conclude that the whales are not present at that time. Although few calves were observed in the NIO, those that were observed, were all observed in November, January or September (but no indication is given of calf size). The authors conclude that this is evidence that the observed whales do not belong to the S. Hem stock, but are more likely from the N.Pacific, despite the fact that there are "no sightings of humpbacks in the south China Sea or the Indonesian Archipelago that could support this assumption". Sperm whales were observed with regularity throughout the year in the NIO, but in lower densities than Rorquals. A low number of sightings in the NIO during summer months again leads the author to conclude that the animals either migrate South or to the N. Pacific. This species, according to the authors is always associated with areas of high productivity.Minke whales were recorded in low densities in the Gulf of Aden and off the coast of Pakistan, but not in the central or Northern coasts of Oman.},
keywords = {Arabian Gulf, Arabian Sea, Atlantic, density, Distribution, fin whale, Gulf of Aden, Humpback Whale, humpback whales, India, Indian Ocean, Maldives, migration, minke whale, minke whales, North Pacific, Oman, Pakistan, productivity, right whale, right whales, Southern Hemisphere, sperm whale, sperm whales, Strandings, whale, whales},
pubstate = {published},
tppubtype = {article}
}
The authors gained the cooperation of the Netherlands Association of Ship Owners and the Royal Netherlands Navy in a project to collect all whale sightings from vessels sailing around the globe between 1954 and 1957. A total of 4500 reports of 11,000 animals were received, with the majority of observations coming from the Atlantic and Indian Oceans. Vessels were given identification guides and all reported observations were scored on the perceived reliability of the identification. All Rorqual whales were grouped together, and a further distinction was made between humpback, sperm, right whales and "little piked whales" (minke whales). Sightings were plotted in 10 degree squares according to number of whales observed per 1000 hours steamed in daylight. Special attention is given to the observations of Captain W.F.J. Morzer Bruins, who the authors describe as a keen naturalist whose observations hold more credibility than those of others. His observations in the Indian Ocean include a high number of sperm whales off the southern coast of Oman and the Gulf of Aden in January-March and April-June, a scattering of stranded blue and fin whales along the W coast of India, and only 2 stranded and 2 live humpback whales (strandings both in India, and live sightings near Yemen/Oman border? and off S tip of India (near Maldives?). The larger number of compiled sightings from vessels are presented by species. Rorqual sightings were plentiful in the Gulf of Aden, Arabian Sea coasts of Oman and Pakistan, and in the Arabian Gulf (but not as plentiful as they were in the area between 30 and 40 degrees S. The author concludes that the majority of the whales observed in the NIO do not belong to the Southern Hemisphere stock, but suggests that they migrate from the North Pacific through the Indonesian Archipelago and the Strait Malaya (despite very few observations here). He briefly considers, but discards as unlikely, the hypothesis of a resident NIO stock.The total number of humpback whale sightings in the IO amounted to 500 (compared to 1618 rorqual sightings and 799 "whale" sightings). The majority of animals were observed in coastal waters, and NIO sightings were generally concentrated in the months of Aug-Nov and Jan-April. some of the highest recorded densities in the NIO are off of Pakistan in the months of March, Aug, Oct, and December, but it is not clear how closely related this is to observer effort. Observations are very few in May, June, July and September, and the authors do not link this to the monsoon -but rather conclude that the whales are not present at that time. Although few calves were observed in the NIO, those that were observed, were all observed in November, January or September (but no indication is given of calf size). The authors conclude that this is evidence that the observed whales do not belong to the S. Hem stock, but are more likely from the N.Pacific, despite the fact that there are "no sightings of humpbacks in the south China Sea or the Indonesian Archipelago that could support this assumption". Sperm whales were observed with regularity throughout the year in the NIO, but in lower densities than Rorquals. A low number of sightings in the NIO during summer months again leads the author to conclude that the animals either migrate South or to the N. Pacific. This species, according to the authors is always associated with areas of high productivity.Minke whales were recorded in low densities in the Gulf of Aden and off the coast of Pakistan, but not in the central or Northern coasts of Oman.