Aneesh Kumar, K. V.,Baby, Sibi T.,Dhaneesh, K. V.,Manjebrayakath, Hashim,Saravanane, N.,Sudhakar, M.
A Stranding Record of Dwarf Sperm Whale Kogia sima in Lakshadweep Archipelago, India and its Genetic Analogy by Molecular Phylogeny Journal Article
In: Thalassas: An International Journal of Marine Sciences, vol. 35, no. 13, pp. 239-245, 2019, ISBN: 2366-1674.
Abstract | Links | BibTeX | Tags: Arabian Sea, India, Indian Ocean, kogia, kogia simus, stranding
@article{,
title = {A Stranding Record of Dwarf Sperm Whale Kogia sima in Lakshadweep Archipelago, India and its Genetic Analogy by Molecular Phylogeny},
author = {Aneesh Kumar, K. V.,Baby, Sibi T.,Dhaneesh, K. V.,Manjebrayakath, Hashim,Saravanane, N.,Sudhakar, M.},
url = {https://doi.org/10.1007/s41208-018-0115-9},
issn = {2366-1674},
year = {2019},
date = {2019-01-01},
journal = {Thalassas: An International Journal of Marine Sciences},
volume = {35},
number = {13},
pages = {239-245},
abstract = {The distribution of Kogiid whales from the Indian Ocean waters, especially Indian waters are poorly known. It is extremely difficult to differentiate the two species (Kogia sima and K. breviceps) based on their morphological characteristics alone. Our study presents the first confirmed record of dwarf sperm whale Kogia sima from the Indian waters using morphological examinations, skull morphology and molecular identification. The study is based on the stranded animal found in the west coast of Agatti Island in Lakshadweep Archipelago belongs to the Indian EEZ. K. sima showed intra-species genetic variability which confirms the isolation of the species in oceans as the tropical nature of the species restricts its movement.},
keywords = {Arabian Sea, India, Indian Ocean, kogia, kogia simus, stranding},
pubstate = {published},
tppubtype = {article}
}
The distribution of Kogiid whales from the Indian Ocean waters, especially Indian waters are poorly known. It is extremely difficult to differentiate the two species (Kogia sima and K. breviceps) based on their morphological characteristics alone. Our study presents the first confirmed record of dwarf sperm whale Kogia sima from the Indian waters using morphological examinations, skull morphology and molecular identification. The study is based on the stranded animal found in the west coast of Agatti Island in Lakshadweep Archipelago belongs to the Indian EEZ. K. sima showed intra-species genetic variability which confirms the isolation of the species in oceans as the tropical nature of the species restricts its movement.
Bopardikar, Isha,Sutaria, Dipani,Sule, Mihir,Jog, Ketki,Patankar, Vardhan,Klinck, Holger
Description and classification of Indian Ocean humpback dolphin (Sousa plumbea) whistles recorded off the Sindhudurg coast of Maharashtra, India Journal Article
In: Marine Mammal Science, vol. 34, no. 3, pp. 755-776, 2018, ISSN: 1748-7692.
Abstract | Links | BibTeX | Tags: Arabian Sea, humpback dolphin, India, passive acoustic monitoring, sousa, Sousa plumbea, vocalization, Whistle, whistles
@article{,
title = {Description and classification of Indian Ocean humpback dolphin (Sousa plumbea) whistles recorded off the Sindhudurg coast of Maharashtra, India},
author = {Bopardikar, Isha,Sutaria, Dipani,Sule, Mihir,Jog, Ketki,Patankar, Vardhan,Klinck, Holger},
url = {http://dx.doi.org/10.1111/mms.12479},
issn = {1748-7692},
year = {2018},
date = {2018-01-01},
journal = {Marine Mammal Science},
volume = {34},
number = {3},
pages = {755-776},
abstract = {The Indian Ocean humpback dolphin (Sousa plumbea), a common cetacean species in India, has a diverse vocal repertoire, which to date has not been described in detail. This study focused on analyzing their whistle vocalizations. Humpback dolphins were recorded off the Sindhudurg coast of Maharashtra, India, and 2,260 whistles were analyzed for their acoustic characteristics. Whistles spanned a wide frequency range between 2.3 kHz and 33.0 kHz, with durations ranging from 0.01 s to 1.60 s. Whistles were categorized into seven contour classes based on their qualitative properties. A classification and regression tree (CART) analysis was used to quantify variability between the seven contour classes using the measured acoustic features. Based on the CART analysis, frequency gradient, minimum slope, maximum slope, beginning and ending slope accounted for most variability between whistle types. CART resulted in an overall classification accuracy of 89.5%. This study provides a detailed description of acoustic features and qualitative properties of humpback dolphin whistles from the northwestern coast of India. Further comparisons of acoustic data from Sousa populations along the Indian coast are necessary to determine possible geographic variations in whistle characteristics and whether the variations are driven by environmental or genetic factors or a combination of both.},
keywords = {Arabian Sea, humpback dolphin, India, passive acoustic monitoring, sousa, Sousa plumbea, vocalization, Whistle, whistles},
pubstate = {published},
tppubtype = {article}
}
The Indian Ocean humpback dolphin (Sousa plumbea), a common cetacean species in India, has a diverse vocal repertoire, which to date has not been described in detail. This study focused on analyzing their whistle vocalizations. Humpback dolphins were recorded off the Sindhudurg coast of Maharashtra, India, and 2,260 whistles were analyzed for their acoustic characteristics. Whistles spanned a wide frequency range between 2.3 kHz and 33.0 kHz, with durations ranging from 0.01 s to 1.60 s. Whistles were categorized into seven contour classes based on their qualitative properties. A classification and regression tree (CART) analysis was used to quantify variability between the seven contour classes using the measured acoustic features. Based on the CART analysis, frequency gradient, minimum slope, maximum slope, beginning and ending slope accounted for most variability between whistle types. CART resulted in an overall classification accuracy of 89.5%. This study provides a detailed description of acoustic features and qualitative properties of humpback dolphin whistles from the northwestern coast of India. Further comparisons of acoustic data from Sousa populations along the Indian coast are necessary to determine possible geographic variations in whistle characteristics and whether the variations are driven by environmental or genetic factors or a combination of both.
Cerchio, S.,Willson, A.,Muirhead, C.,Al Harthi, S.,Baldwin, R.,Bonato, M,Collins, T.,Di Clemente, J.,Dulau, Violaine,Estrade, Vanessa,Latha, G,Minton, A. Gianna.,Sarrouf Willson, M.
Geographic variation in song indicates both isolation of Arabian Sea humpback whales and presence of Southern Hemisphere whales off Oman Technical Report
no. 342, 2018, ISSN: IWC/SC67B/CMP19.
Abstract | Links | BibTeX | Tags: Humpback Whale, India, Indian Ocean, megaptera novaeangliae, Oman, population structure, Reunion, song
@techreport{,
title = {Geographic variation in song indicates both isolation of Arabian Sea humpback whales and presence of Southern Hemisphere whales off Oman},
author = {Cerchio, S.,Willson, A.,Muirhead, C.,Al Harthi, S.,Baldwin, R.,Bonato, M,Collins, T.,Di Clemente, J.,Dulau, Violaine,Estrade, Vanessa,Latha, G,Minton, A. Gianna.,Sarrouf Willson, M.},
url = {https://arabianseawhalenetwork.org/wp-content/uploads/2018/05/sc_67b_cmp_19_oman-humpback-whale-song-analysis-and-comparison-1.pdf},
issn = {IWC/SC67B/CMP19},
year = {2018},
date = {2018-01-01},
journal = {Document presented to the Scientific Committee of the International Whaling Commission},
number = {342},
pages = {31},
publisher = {International Whaling Commission},
abstract = {Existing genetic, demographic and behavioral evidence indicates that Arabian Sea humpback whales
represent an isolated and unique population. The population exhibits a Northern Hemisphere breeding
cycle, is believed to feed year-round, and lacks the typical latitudinal migrations and seasonal separation
of breeding and feeding ecology exhibited by other populations of humpback whales globally. A key
feature of humpback whale breeding behavior is the male acoustic breeding display, song, studied
extensively around the world. Key characteristics of humpback whale song include: all males within a
population share the same song patterns (phrases); a population’s song changes progressively over time;
and populations that do not overlap or exchange individuals have distinctly different songs, whereas
populations in contact share some or all phrases. Here we use long-term acoustic monitoring off the coast
of Oman to further assess the isolation of the Arabian Sea population. A total of 76 samples (amounting
to 4,434 minutes of recording) of Arabian Sea song collected between 2011 and 2013 were examined, and
phrase content was characterized and compared to 23 samples (totaling 202 min of recording) collected
during the same years in the Southwest Indian Ocean from Reunion Island and the Comoros Islands. Song
from the Arabian Sea and the Southwest Indian Ocean was distinct across the entire study period, with no
evidence for shared phrases in any year. In addition, song fragments recorded off western India in 2011
were composed of two phrases present in the Oman song, suggesting continuity across the Arabian Sea.
Moreover, the Arabian Sea song exhibited a markedly atypical low level of temporal variation, with song
phrases remaining virtually unchanged during the three examined breeding seasons. Notably, Southwest
Indian Ocean song was recorded off the coast of Oman in August 2012 (Boreal summer, Austral winter).
This song was recorded on multiple days and included multiple simultaneous singers over a 25 day period
indicating the presence of more than a single accidental vagrant Southern Hemisphere animal. We suggest
that these Southern songs were produced by Southwest Indian Ocean animals moving into the Arabian
Sea, and that this may be more common than is currently thought. The low level of temporal variation
shown by the Arabian Sea males along with the lack of adoption of the Southwest Indian Ocean song
material, further indicate the uniqueness and distinct nature of this population. It seems possible that
isolation mechanisms exist that may inhibit the mixing of the Arabian Sea population with Southern
Hemisphere animals, and that this may be reflected in the observed atypical song behavior.},
keywords = {Humpback Whale, India, Indian Ocean, megaptera novaeangliae, Oman, population structure, Reunion, song},
pubstate = {published},
tppubtype = {techreport}
}
Existing genetic, demographic and behavioral evidence indicates that Arabian Sea humpback whales
represent an isolated and unique population. The population exhibits a Northern Hemisphere breeding
cycle, is believed to feed year-round, and lacks the typical latitudinal migrations and seasonal separation
of breeding and feeding ecology exhibited by other populations of humpback whales globally. A key
feature of humpback whale breeding behavior is the male acoustic breeding display, song, studied
extensively around the world. Key characteristics of humpback whale song include: all males within a
population share the same song patterns (phrases); a population’s song changes progressively over time;
and populations that do not overlap or exchange individuals have distinctly different songs, whereas
populations in contact share some or all phrases. Here we use long-term acoustic monitoring off the coast
of Oman to further assess the isolation of the Arabian Sea population. A total of 76 samples (amounting
to 4,434 minutes of recording) of Arabian Sea song collected between 2011 and 2013 were examined, and
phrase content was characterized and compared to 23 samples (totaling 202 min of recording) collected
during the same years in the Southwest Indian Ocean from Reunion Island and the Comoros Islands. Song
from the Arabian Sea and the Southwest Indian Ocean was distinct across the entire study period, with no
evidence for shared phrases in any year. In addition, song fragments recorded off western India in 2011
were composed of two phrases present in the Oman song, suggesting continuity across the Arabian Sea.
Moreover, the Arabian Sea song exhibited a markedly atypical low level of temporal variation, with song
phrases remaining virtually unchanged during the three examined breeding seasons. Notably, Southwest
Indian Ocean song was recorded off the coast of Oman in August 2012 (Boreal summer, Austral winter).
This song was recorded on multiple days and included multiple simultaneous singers over a 25 day period
indicating the presence of more than a single accidental vagrant Southern Hemisphere animal. We suggest
that these Southern songs were produced by Southwest Indian Ocean animals moving into the Arabian
Sea, and that this may be more common than is currently thought. The low level of temporal variation
shown by the Arabian Sea males along with the lack of adoption of the Southwest Indian Ocean song
material, further indicate the uniqueness and distinct nature of this population. It seems possible that
isolation mechanisms exist that may inhibit the mixing of the Arabian Sea population with Southern
Hemisphere animals, and that this may be reflected in the observed atypical song behavior.
represent an isolated and unique population. The population exhibits a Northern Hemisphere breeding
cycle, is believed to feed year-round, and lacks the typical latitudinal migrations and seasonal separation
of breeding and feeding ecology exhibited by other populations of humpback whales globally. A key
feature of humpback whale breeding behavior is the male acoustic breeding display, song, studied
extensively around the world. Key characteristics of humpback whale song include: all males within a
population share the same song patterns (phrases); a population’s song changes progressively over time;
and populations that do not overlap or exchange individuals have distinctly different songs, whereas
populations in contact share some or all phrases. Here we use long-term acoustic monitoring off the coast
of Oman to further assess the isolation of the Arabian Sea population. A total of 76 samples (amounting
to 4,434 minutes of recording) of Arabian Sea song collected between 2011 and 2013 were examined, and
phrase content was characterized and compared to 23 samples (totaling 202 min of recording) collected
during the same years in the Southwest Indian Ocean from Reunion Island and the Comoros Islands. Song
from the Arabian Sea and the Southwest Indian Ocean was distinct across the entire study period, with no
evidence for shared phrases in any year. In addition, song fragments recorded off western India in 2011
were composed of two phrases present in the Oman song, suggesting continuity across the Arabian Sea.
Moreover, the Arabian Sea song exhibited a markedly atypical low level of temporal variation, with song
phrases remaining virtually unchanged during the three examined breeding seasons. Notably, Southwest
Indian Ocean song was recorded off the coast of Oman in August 2012 (Boreal summer, Austral winter).
This song was recorded on multiple days and included multiple simultaneous singers over a 25 day period
indicating the presence of more than a single accidental vagrant Southern Hemisphere animal. We suggest
that these Southern songs were produced by Southwest Indian Ocean animals moving into the Arabian
Sea, and that this may be more common than is currently thought. The low level of temporal variation
shown by the Arabian Sea males along with the lack of adoption of the Southwest Indian Ocean song
material, further indicate the uniqueness and distinct nature of this population. It seems possible that
isolation mechanisms exist that may inhibit the mixing of the Arabian Sea population with Southern
Hemisphere animals, and that this may be reflected in the observed atypical song behavior.
Madhusudhana, Shyam Kumar,Chakraborty, Bishwajit,Latha, G.
Humpback whale singing activity off the Goan coast in the Eastern Arabian Sea Journal Article
In: Bioacoustics, no. 147, pp. 1-16, 2018, ISBN: 0952-4622.
Abstract | Links | BibTeX | Tags: Arabian Sea, breeding, Goa, Humpback Whale, India, Megaptera novaeanglia, PAM, passive acoustic monitoring, song, vocal behaviour
@article{,
title = {Humpback whale singing activity off the Goan coast in the Eastern Arabian Sea},
author = {Madhusudhana, Shyam Kumar,Chakraborty, Bishwajit,Latha, G.},
url = {https://doi.org/10.1080/09524622.2018.1458248},
issn = {0952-4622},
year = {2018},
date = {2018-01-01},
journal = {Bioacoustics},
number = {147},
pages = {1-16},
publisher = {Taylor & Francis},
abstract = {AbstractFor over two decades, passive acoustic monitoring (PAM) methods have been successfully employed around the world for studying aquatic megafauna. PAM-driven studies in Indian waters have so far been relatively very scarce. Furthermore, cetacean populations inhabiting the north western Indian Ocean are far less studied than those in many other regions around the world. This work likely constitutes the first systematic study of the vocal repertoire of humpback whales (Megaptera novaeangliae) at a near-shore site along the western coast of India. Analysis of the observed vocalizations provides an insight into the behaviour of the species. This is significant as it assists in developing a better understanding of the habitat use of the non-migratory Arabian Sea humpback whale population. In contrast, other breeding populations such as those around the North Atlantic, South Pacific and Australia have been relatively well studied. Underwater passive acoustic data were collected during March 2017 using an autonomous logger at a shallow-water site off the eastern edge of Grande Island off the coast of Goa. Humpback whale vocalizations were found to occur over multiple days in the recordings. Time?frequency contours of individual units of vocalization were extracted with the aid of an automatic detection technique and the characteristics of the units were measured. Further, successive units were analysed for formation of phrases and themes. Reconstruction of putative songs from the identified units and themes was not possible due to the limitations imposed by the nature of data collection. Detailed analyses of units, phrases and themes are presented.},
keywords = {Arabian Sea, breeding, Goa, Humpback Whale, India, Megaptera novaeanglia, PAM, passive acoustic monitoring, song, vocal behaviour},
pubstate = {published},
tppubtype = {article}
}
AbstractFor over two decades, passive acoustic monitoring (PAM) methods have been successfully employed around the world for studying aquatic megafauna. PAM-driven studies in Indian waters have so far been relatively very scarce. Furthermore, cetacean populations inhabiting the north western Indian Ocean are far less studied than those in many other regions around the world. This work likely constitutes the first systematic study of the vocal repertoire of humpback whales (Megaptera novaeangliae) at a near-shore site along the western coast of India. Analysis of the observed vocalizations provides an insight into the behaviour of the species. This is significant as it assists in developing a better understanding of the habitat use of the non-migratory Arabian Sea humpback whale population. In contrast, other breeding populations such as those around the North Atlantic, South Pacific and Australia have been relatively well studied. Underwater passive acoustic data were collected during March 2017 using an autonomous logger at a shallow-water site off the eastern edge of Grande Island off the coast of Goa. Humpback whale vocalizations were found to occur over multiple days in the recordings. Time?frequency contours of individual units of vocalization were extracted with the aid of an automatic detection technique and the characteristics of the units were measured. Further, successive units were analysed for formation of phrases and themes. Reconstruction of putative songs from the identified units and themes was not possible due to the limitations imposed by the nature of data collection. Detailed analyses of units, phrases and themes are presented.
Jog, Ketki,Sule, Mihir,Bopardikar, Isha,Patankar, Vardhan,Sutaria, Dipani
Living with dolphins: Local ecological knowledge and perceptions of small cetaceans along the Sindhudurg coastline of Maharashtra, India Journal Article
In: Marine Mammal Science, vol. 34, no. 128, pp. 488-498, 2017, ISBN: 1748-7692.
Abstract | Links | BibTeX | Tags: Arabian Sea, Bycatch, cetacean-fisheries interactions, competition, Finless Porpoise, humpback dolphin, India, local ecological knowledge, Marine mammals, Neophocaena phocaenoides, perceptions, Sousa plumbea
@article{,
title = {Living with dolphins: Local ecological knowledge and perceptions of small cetaceans along the Sindhudurg coastline of Maharashtra, India},
author = {Jog, Ketki,Sule, Mihir,Bopardikar, Isha,Patankar, Vardhan,Sutaria, Dipani},
url = {http://dx.doi.org/10.1111/mms.12466},
issn = {1748-7692},
year = {2017},
date = {2017-01-01},
journal = {Marine Mammal Science},
volume = {34},
number = {128},
pages = {488-498},
abstract = {Two near shore small cetaceans occur commonly along the Maharashtra coast, the Indian Ocean humpback dolphin and Indo Pacific finless porpoise. These cetaceans frequently interact with fisheries in this region due to overlap in space and resource use. Besides stranding records, little ecological information is available about these species from Maharashtra. We conducted 143 semistructured interviews to document local ecological knowledge and community perceptions of small cetaceans in 30 coastal fishing villages in Sindhudurg. Perceptions of finless porpoises were largely neutral, whereas humpback dolphins were negative. A classification regression tree (CART) analysis (root node error: 60%) showed that the annual cost of gear damage was an important predictor variable of humpback dolphin perceptions, followed by occupation (gear type) and age. Entanglements were reported for both species in large and small gill nets, and shore seines. Perceived net damage and catch loss due to humpback dolphins was six times greater than that of finless porpoises. However, finless porpoises were reportedly more frequently entangled in gear than humpback dolphins. We provide an insight into the perceptions of cetaceans in the local community and the fisheries-cetacean interactions that shape them.},
keywords = {Arabian Sea, Bycatch, cetacean-fisheries interactions, competition, Finless Porpoise, humpback dolphin, India, local ecological knowledge, Marine mammals, Neophocaena phocaenoides, perceptions, Sousa plumbea},
pubstate = {published},
tppubtype = {article}
}
Two near shore small cetaceans occur commonly along the Maharashtra coast, the Indian Ocean humpback dolphin and Indo Pacific finless porpoise. These cetaceans frequently interact with fisheries in this region due to overlap in space and resource use. Besides stranding records, little ecological information is available about these species from Maharashtra. We conducted 143 semistructured interviews to document local ecological knowledge and community perceptions of small cetaceans in 30 coastal fishing villages in Sindhudurg. Perceptions of finless porpoises were largely neutral, whereas humpback dolphins were negative. A classification regression tree (CART) analysis (root node error: 60%) showed that the annual cost of gear damage was an important predictor variable of humpback dolphin perceptions, followed by occupation (gear type) and age. Entanglements were reported for both species in large and small gill nets, and shore seines. Perceived net damage and catch loss due to humpback dolphins was six times greater than that of finless porpoises. However, finless porpoises were reportedly more frequently entangled in gear than humpback dolphins. We provide an insight into the perceptions of cetaceans in the local community and the fisheries-cetacean interactions that shape them.
NOAA
Taking and Importing of Marine Mammals and Dolphin-Safe Tuna Products Journal Article
In: Federal Register, vol. 81, no. 421, pp. 3, 2016.
Abstract | BibTeX | Tags: Arabian Sea, Bycatch, Fisheries, India, Marine mammals, NIO, Observer programmes, Oman, Pakistan, reporting scheme, Tanzania, tuna fishery
@article{,
title = {Taking and Importing of Marine Mammals and Dolphin-Safe Tuna Products },
author = {NOAA},
year = {2016},
date = {2016-01-01},
journal = {Federal Register},
volume = {81},
number = {421},
pages = {3},
abstract = { The Assistant Administrator
for Fisheries, NMFS, (Assistant
Administrator) has issued a
determination, under the Dolphin
Protection Consumer Information Act
(DPCIA), of regular and significant
mortality and serious injury of dolphins
in gillnet fisheries harvesting tuna by
vessels flagged under the Governments
of India, Iran, Mozambique, Pakistan,
Oman, Saudi Arabia, Sri Lanka,
Tanzania, the United Arab Emirates,
and Yemen. This determination triggers
additional documentation requirements
for tuna product from those fisheries
that is exported from or offered for sale
in the United States, including that such
tuna must be accompanied by a written
statement executed by an observer
participating in a national or
international program acceptable to the
Assistant Administrator, in addition to
such statement by the captain of the
vessel, that certifies that no dolphins
were killed or seriously injured in the
sets or other gear deployments in which
the tuna were caught and certain other
required information regarding dolphin
interactions and segregation of tuna.
These determinations were based on
review of scientific information and,
when available, documentary evidence
submitted by the relevant government. },
keywords = {Arabian Sea, Bycatch, Fisheries, India, Marine mammals, NIO, Observer programmes, Oman, Pakistan, reporting scheme, Tanzania, tuna fishery},
pubstate = {published},
tppubtype = {article}
}
The Assistant Administrator
for Fisheries, NMFS, (Assistant
Administrator) has issued a
determination, under the Dolphin
Protection Consumer Information Act
(DPCIA), of regular and significant
mortality and serious injury of dolphins
in gillnet fisheries harvesting tuna by
vessels flagged under the Governments
of India, Iran, Mozambique, Pakistan,
Oman, Saudi Arabia, Sri Lanka,
Tanzania, the United Arab Emirates,
and Yemen. This determination triggers
additional documentation requirements
for tuna product from those fisheries
that is exported from or offered for sale
in the United States, including that such
tuna must be accompanied by a written
statement executed by an observer
participating in a national or
international program acceptable to the
Assistant Administrator, in addition to
such statement by the captain of the
vessel, that certifies that no dolphins
were killed or seriously injured in the
sets or other gear deployments in which
the tuna were caught and certain other
required information regarding dolphin
interactions and segregation of tuna.
These determinations were based on
review of scientific information and,
when available, documentary evidence
submitted by the relevant government.
for Fisheries, NMFS, (Assistant
Administrator) has issued a
determination, under the Dolphin
Protection Consumer Information Act
(DPCIA), of regular and significant
mortality and serious injury of dolphins
in gillnet fisheries harvesting tuna by
vessels flagged under the Governments
of India, Iran, Mozambique, Pakistan,
Oman, Saudi Arabia, Sri Lanka,
Tanzania, the United Arab Emirates,
and Yemen. This determination triggers
additional documentation requirements
for tuna product from those fisheries
that is exported from or offered for sale
in the United States, including that such
tuna must be accompanied by a written
statement executed by an observer
participating in a national or
international program acceptable to the
Assistant Administrator, in addition to
such statement by the captain of the
vessel, that certifies that no dolphins
were killed or seriously injured in the
sets or other gear deployments in which
the tuna were caught and certain other
required information regarding dolphin
interactions and segregation of tuna.
These determinations were based on
review of scientific information and,
when available, documentary evidence
submitted by the relevant government.
Mahanty, Madan M,Latha, G,Thirunavukkarasu, A
Analysis of humpback whale sounds in shallow waters of the Southeastern Arabian Sea: An indication of breeding habitat Journal Article
In: Journal of biosciences, vol. 40, no. 148, pp. 407-417, 2015, ISBN: 0250-5991.
Abstract | BibTeX | Tags: Arabian Sea, behaviour, breeding grounds, Humpback Whale, India, megaptera novaeangliae, song
@article{,
title = {Analysis of humpback whale sounds in shallow waters of the Southeastern Arabian Sea: An indication of breeding habitat},
author = {Mahanty, Madan M,Latha, G,Thirunavukkarasu, A},
issn = {0250-5991},
year = {2015},
date = {2015-01-01},
journal = {Journal of biosciences},
volume = {40},
number = {148},
pages = {407-417},
abstract = {The primary objective of this work was to present the acoustical identification of humpback whales, detected by using
an autonomous ambient noise measurement system, deployed in the shallow waters of the Southeastern Arabian Sea
(SEAS) during the period January to May 2011. Seven types of sounds were detected. These were characteristically
upsweeps and downsweeps along with harmonics. Sounds produced repeatedly in a specific pattern were referred to as
phrases (PQRS and ABC). Repeated phrases in a particular pattern were referred to as themes, and from the
spectrographic analysis, two themes (I and II) were identified. The variation in the acoustic characteristics such as
fundamental frequency, range, duration of the sound unit, and the structure of the phrases and themes are discussed.
Sound units were recorded from mid-January to mid-March, with a peak in February, when the mean SST is ~28°C,
and no presence was recorded after mid-March. The temporal and thematic structures strongly determine the functions
of the humpback whale song form. Given the use of song in the SEAS, this area is possibly used as an active breeding
habitat by humpback whales during the winter season.},
keywords = {Arabian Sea, behaviour, breeding grounds, Humpback Whale, India, megaptera novaeangliae, song},
pubstate = {published},
tppubtype = {article}
}
The primary objective of this work was to present the acoustical identification of humpback whales, detected by using
an autonomous ambient noise measurement system, deployed in the shallow waters of the Southeastern Arabian Sea
(SEAS) during the period January to May 2011. Seven types of sounds were detected. These were characteristically
upsweeps and downsweeps along with harmonics. Sounds produced repeatedly in a specific pattern were referred to as
phrases (PQRS and ABC). Repeated phrases in a particular pattern were referred to as themes, and from the
spectrographic analysis, two themes (I and II) were identified. The variation in the acoustic characteristics such as
fundamental frequency, range, duration of the sound unit, and the structure of the phrases and themes are discussed.
Sound units were recorded from mid-January to mid-March, with a peak in February, when the mean SST is ~28°C,
and no presence was recorded after mid-March. The temporal and thematic structures strongly determine the functions
of the humpback whale song form. Given the use of song in the SEAS, this area is possibly used as an active breeding
habitat by humpback whales during the winter season.
an autonomous ambient noise measurement system, deployed in the shallow waters of the Southeastern Arabian Sea
(SEAS) during the period January to May 2011. Seven types of sounds were detected. These were characteristically
upsweeps and downsweeps along with harmonics. Sounds produced repeatedly in a specific pattern were referred to as
phrases (PQRS and ABC). Repeated phrases in a particular pattern were referred to as themes, and from the
spectrographic analysis, two themes (I and II) were identified. The variation in the acoustic characteristics such as
fundamental frequency, range, duration of the sound unit, and the structure of the phrases and themes are discussed.
Sound units were recorded from mid-January to mid-March, with a peak in February, when the mean SST is ~28°C,
and no presence was recorded after mid-March. The temporal and thematic structures strongly determine the functions
of the humpback whale song form. Given the use of song in the SEAS, this area is possibly used as an active breeding
habitat by humpback whales during the winter season.
Pande, Satish.,Sant, Niranjan.,Pednekar, Shivkumar.,Pradhan, M. S.
Definite records of Sperm Whale Journal Article
In: Journal of Threatened Taxa, vol. 1, no. 186, pp. 180-181, 2009.
BibTeX | Tags: Arabian Sea, bottlenose dolphins, India, sperm whale, Spinner dolphin
@article{,
title = {Definite records of Sperm Whale },
author = {Pande, Satish.,Sant, Niranjan.,Pednekar, Shivkumar.,Pradhan, M. S.},
year = {2009},
date = {2009-01-01},
journal = {Journal of Threatened Taxa},
volume = {1},
number = {186},
pages = {180-181},
keywords = {Arabian Sea, bottlenose dolphins, India, sperm whale, Spinner dolphin},
pubstate = {published},
tppubtype = {article}
}
Afsal, V.V.,Yousuf, K.M.M.,Anoop, B.,Anoop, A. K.,Kannan, P.,Rajagopalan, M.,Vivekanandan, E.
A note on cetacean distribution in the Indian EEZ and contiguous seas during 2003-07 Journal Article
In: Journal of Cetacean Research and Management, vol. 10, no. 2, pp. 209-215, 2008.
BibTeX | Tags: Arabian Sea, Bay of Bengal, Distribution, India, Indian Ocean
@article{,
title = {A note on cetacean distribution in the Indian EEZ and contiguous seas during 2003-07},
author = {Afsal, V.V.,Yousuf, K.M.M.,Anoop, B.,Anoop, A. K.,Kannan, P.,Rajagopalan, M.,Vivekanandan, E.},
year = {2008},
date = {2008-01-01},
journal = {Journal of Cetacean Research and Management},
volume = {10},
number = {2},
pages = {209-215},
keywords = {Arabian Sea, Bay of Bengal, Distribution, India, Indian Ocean},
pubstate = {published},
tppubtype = {article}
}
Jayasankar, P.,Anoop, B.,Vivekanandan, E.,Rajagopalan, M.,Yousuf, K.M.M.,Reynolds, P.,Krishnakumar, P.K.,Kumaran, PL.,Afsal, V.V.,Krishnan, A.A.
Molecular identification of delphinids and finless porpoise (Cetacea) from the Arabian Sea and Bay of Bengal Journal Article
In: Zootaxa, vol. 1853, no. 125, pp. 57-67, 2008.
Abstract | BibTeX | Tags: bottlenose dolphin, Common dolphin, D.capensis, DNA, Finless Porpoise, India, Neophocaena phocaenoides, sousa, species identification, Spinner dolphin, Stenella longirostris, taxonomy, tursiops aduncus
@article{,
title = {Molecular identification of delphinids and finless porpoise (Cetacea) from the Arabian Sea and Bay of Bengal},
author = {Jayasankar, P.,Anoop, B.,Vivekanandan, E.,Rajagopalan, M.,Yousuf, K.M.M.,Reynolds, P.,Krishnakumar, P.K.,Kumaran, PL.,Afsal, V.V.,Krishnan, A.A.},
year = {2008},
date = {2008-01-01},
journal = {Zootaxa},
volume = {1853},
number = {125},
pages = {57-67},
abstract = {The exact number of extant delphinid species from seas around India is still debated and the lack of adequate field keys
and reliable inventory has resulted in misidentification of several species. As a part of a project to develop a molecular
taxonomy of cetaceans from this region, partial sequences of mtDNA cytochrome b were generated from accidentally
caught/stranded delphinids and finless porpoise. Species were identified by phylogenetic reconstruction of sample
sequences with the reference sequences available in portals GenBank (NCBI) and the web-based program DNA Surveillance.
A comparison was made with the homologous sequences of corresponding species from other seas of the world.
Our molecular investigations allowed us to identify five species of cetaceans from Indian coasts, including Delphinus
capensis, previously reported as D. delphis. We detected unique haplotypes in Indo pacific humpbacked dolphin (Sousa
chinensis; n = 2) and finless porpoise (Neophocaena phocaenoides; n = 12) from Indian coast. On the other hand, some
haplotypes were shared with other regional populations in spinner dolphin (Stenella longirostris; n = 16) and bottlenose
dolphin (Tursiops aduncus; n = 3). Common dolphins (Delphinus capensis; n = 2) had both unique and shared haplotypes
including one highly divergent sequence.},
keywords = {bottlenose dolphin, Common dolphin, D.capensis, DNA, Finless Porpoise, India, Neophocaena phocaenoides, sousa, species identification, Spinner dolphin, Stenella longirostris, taxonomy, tursiops aduncus},
pubstate = {published},
tppubtype = {article}
}
The exact number of extant delphinid species from seas around India is still debated and the lack of adequate field keys
and reliable inventory has resulted in misidentification of several species. As a part of a project to develop a molecular
taxonomy of cetaceans from this region, partial sequences of mtDNA cytochrome b were generated from accidentally
caught/stranded delphinids and finless porpoise. Species were identified by phylogenetic reconstruction of sample
sequences with the reference sequences available in portals GenBank (NCBI) and the web-based program DNA Surveillance.
A comparison was made with the homologous sequences of corresponding species from other seas of the world.
Our molecular investigations allowed us to identify five species of cetaceans from Indian coasts, including Delphinus
capensis, previously reported as D. delphis. We detected unique haplotypes in Indo pacific humpbacked dolphin (Sousa
chinensis; n = 2) and finless porpoise (Neophocaena phocaenoides; n = 12) from Indian coast. On the other hand, some
haplotypes were shared with other regional populations in spinner dolphin (Stenella longirostris; n = 16) and bottlenose
dolphin (Tursiops aduncus; n = 3). Common dolphins (Delphinus capensis; n = 2) had both unique and shared haplotypes
including one highly divergent sequence.
and reliable inventory has resulted in misidentification of several species. As a part of a project to develop a molecular
taxonomy of cetaceans from this region, partial sequences of mtDNA cytochrome b were generated from accidentally
caught/stranded delphinids and finless porpoise. Species were identified by phylogenetic reconstruction of sample
sequences with the reference sequences available in portals GenBank (NCBI) and the web-based program DNA Surveillance.
A comparison was made with the homologous sequences of corresponding species from other seas of the world.
Our molecular investigations allowed us to identify five species of cetaceans from Indian coasts, including Delphinus
capensis, previously reported as D. delphis. We detected unique haplotypes in Indo pacific humpbacked dolphin (Sousa
chinensis; n = 2) and finless porpoise (Neophocaena phocaenoides; n = 12) from Indian coast. On the other hand, some
haplotypes were shared with other regional populations in spinner dolphin (Stenella longirostris; n = 16) and bottlenose
dolphin (Tursiops aduncus; n = 3). Common dolphins (Delphinus capensis; n = 2) had both unique and shared haplotypes
including one highly divergent sequence.
Farrenkopf,A.M.,Luther III,G.W.
Iodine chemistry reflects productivity and denitrification in the Arabian Sea: evidence for flux of dissolved species from sediments of western India into the OMZ Journal Article
In: Deep-Sea Research Part II, vol. 49 , no. 91, pp. 2303-2318, 2002.
Abstract | BibTeX | Tags: Arabian Sea, Atlantic, Hawaii, India, Oceanic, oxygen minimum, productivity
@article{,
title = {Iodine chemistry reflects productivity and denitrification in the Arabian Sea: evidence for flux of dissolved species from sediments of western India into the OMZ},
author = {Farrenkopf,A.M.,Luther III,G.W.},
year = {2002},
date = {2002-01-01},
journal = {Deep-Sea Research Part II},
volume = {49 },
number = {91},
pages = {2303-2318},
abstract = {Dissolved iodine species and total iodine concentrations were measured in the Arabian Sea during the Spring Intermonsoon of 1995. Two separate regimes of iodine chemistry are highlighted in this study: (1) the well-oxygenated surface layer (WOSL) where iodide concentrations were in the range of 158-558 nM, and (2) the oxygen minimum zone (OMZ) where total iodine concentrations [primarily as iodide and in excess to the oceanic iodine/salinity ratio of ~13] varied from ~200 to 950 nM. Iodine data in the WOSL of the Arabian Sea are contrasted with data from the Bermuda Atlantic Time-series Station (BATS), the Hawaii Ocean Time-series Station ALOHA (HOT), VERTEX in the Pacific and the Black Sea. Total iodine concentrations in excess of 400nM were observed in eastern portions of the OMZ. The eastern portion of the basin has a permanent denitrification zone as well as high concentrations of dissolved Mn2+ (d- Mn2+) and iodide. While there is precedent for high values of iodide and total iodine in several other isolated basins, this is the first report of such values in open-ocean waters. Potential sources of excess total iodine to the OMZ include advection along isopycnals, from hydrothermal vents or margin sediments; atmospheric deposition; and remineralization of sinking particulate organic iodine (POI) associated with elevated productivity in surface waters. We estimate that only 3.6% of the excess total iodine can result from remineralization of sinking POI from the WOSL to the OMZ. Advection from margin sediments off of India is the most plausible source of iodine to the OMZ and contributes ~96% of the total excess iodine to the OMZ. I- is maintained as the dominant form of iodine via in situ reduction of iodate by bacteria.},
keywords = {Arabian Sea, Atlantic, Hawaii, India, Oceanic, oxygen minimum, productivity},
pubstate = {published},
tppubtype = {article}
}
Dissolved iodine species and total iodine concentrations were measured in the Arabian Sea during the Spring Intermonsoon of 1995. Two separate regimes of iodine chemistry are highlighted in this study: (1) the well-oxygenated surface layer (WOSL) where iodide concentrations were in the range of 158-558 nM, and (2) the oxygen minimum zone (OMZ) where total iodine concentrations [primarily as iodide and in excess to the oceanic iodine/salinity ratio of ~13] varied from ~200 to 950 nM. Iodine data in the WOSL of the Arabian Sea are contrasted with data from the Bermuda Atlantic Time-series Station (BATS), the Hawaii Ocean Time-series Station ALOHA (HOT), VERTEX in the Pacific and the Black Sea. Total iodine concentrations in excess of 400nM were observed in eastern portions of the OMZ. The eastern portion of the basin has a permanent denitrification zone as well as high concentrations of dissolved Mn2+ (d- Mn2+) and iodide. While there is precedent for high values of iodide and total iodine in several other isolated basins, this is the first report of such values in open-ocean waters. Potential sources of excess total iodine to the OMZ include advection along isopycnals, from hydrothermal vents or margin sediments; atmospheric deposition; and remineralization of sinking particulate organic iodine (POI) associated with elevated productivity in surface waters. We estimate that only 3.6% of the excess total iodine can result from remineralization of sinking POI from the WOSL to the OMZ. Advection from margin sediments off of India is the most plausible source of iodine to the OMZ and contributes ~96% of the total excess iodine to the OMZ. I- is maintained as the dominant form of iodine via in situ reduction of iodate by bacteria.
Mikhalev,Y.A.
Humpback whales Megaptera novaeangliae in the Arabian Sea Journal Article
In: Marine Ecology Progress Series, vol. 149, no. 154, pp. 13-21, 1997.
Abstract | BibTeX | Tags: Antarctic, Arabian Sea, Distribution, Humpback Whale, humpback whales, India, Indian Ocean, length, megaptera novaeangliae, Northern Hemisphere, Oman, Pakistan, pathology, population, Population Biology, population identity, reproduction, whale, whales, whaling
@article{,
title = {Humpback whales Megaptera novaeangliae in the Arabian Sea},
author = {Mikhalev,Y.A.},
year = {1997},
date = {1997-01-01},
journal = {Marine Ecology Progress Series},
volume = {149},
number = {154},
pages = {13-21},
abstract = {The population identity of humpback whales Megaptera novaeangliae in the Arabian Sea has long been a matter of dispute. New information is presented from this region, based upon whaling and observations conducted by the Soviet Union, primarily in November 1966. In that month, a total of 238 humpbacks were killed off the coasts of Oman, Pakistan and northwestern India; 4 others were killed in 1965. Biological examination of these whales showed that they differed significantly from Antarctic humpbacks in terms of size, coloration, body scars and pathology. In addition, analysis of the length distribution of 38 foetuses indicates that the reproductive cycle of the Arabian Sea whales was unequivocally that of a northern hemisphere population. Mean lengths were 12.8 m for males (range: 9.5 to 14.9 m, n = 126) and 13.3 m for females (range: 9.5 to 15.2 m, n = 112). All whales 12.5 m or more in length were sexually mature. Among 97 females examined, 12 (12.4%) were immature. Of the 85 mature females, 39 (45.9%) were pregnant, 3 (3.5%) were lactating, and 43 (50.6%) were resting. A more plausible pregnancy rate, adjusted for underrepresentation of lactating females, was estimated at 39%. A majority of stomachs examined contained food, including euphausiids and fish. Overall, the data presented here argue strongly that Arabian Sea humpbacks constitute a discrete population which remains in tropical waters year-round, a situation which is unique for this species.},
keywords = {Antarctic, Arabian Sea, Distribution, Humpback Whale, humpback whales, India, Indian Ocean, length, megaptera novaeangliae, Northern Hemisphere, Oman, Pakistan, pathology, population, Population Biology, population identity, reproduction, whale, whales, whaling},
pubstate = {published},
tppubtype = {article}
}
The population identity of humpback whales Megaptera novaeangliae in the Arabian Sea has long been a matter of dispute. New information is presented from this region, based upon whaling and observations conducted by the Soviet Union, primarily in November 1966. In that month, a total of 238 humpbacks were killed off the coasts of Oman, Pakistan and northwestern India; 4 others were killed in 1965. Biological examination of these whales showed that they differed significantly from Antarctic humpbacks in terms of size, coloration, body scars and pathology. In addition, analysis of the length distribution of 38 foetuses indicates that the reproductive cycle of the Arabian Sea whales was unequivocally that of a northern hemisphere population. Mean lengths were 12.8 m for males (range: 9.5 to 14.9 m, n = 126) and 13.3 m for females (range: 9.5 to 15.2 m, n = 112). All whales 12.5 m or more in length were sexually mature. Among 97 females examined, 12 (12.4%) were immature. Of the 85 mature females, 39 (45.9%) were pregnant, 3 (3.5%) were lactating, and 43 (50.6%) were resting. A more plausible pregnancy rate, adjusted for underrepresentation of lactating females, was estimated at 39%. A majority of stomachs examined contained food, including euphausiids and fish. Overall, the data presented here argue strongly that Arabian Sea humpbacks constitute a discrete population which remains in tropical waters year-round, a situation which is unique for this species.
Tudhope,A.W.,Lea,D.W.,Shimmield,G.B.,Chilcott,C.P.,Head,S.
Monsoon climate and Arabian Sea coastal upwelling recorded in massive corals from southern Oman Journal Article
In: Palaios, vol. 11, no. 486, pp. 347-361, 1996.
Abstract | BibTeX | Tags: Arabian Sea, coral, India, Oman, surface temperature, temperature, Upwelling
@article{,
title = {Monsoon climate and Arabian Sea coastal upwelling recorded in massive corals from southern Oman},
author = {Tudhope,A.W.,Lea,D.W.,Shimmield,G.B.,Chilcott,C.P.,Head,S.},
year = {1996},
date = {1996-01-01},
journal = {Palaios},
volume = {11},
number = {486},
pages = {347-361},
abstract = {Corals living in the coastal waters of southern Oman experience the influence of the seasonally reversing Asian monsoon system. The objective of the research reported here is to assess the potential for using the skeletal chemistry of these corals to investigate past variability in the monsoon climate. To this end, 20-year long, monthly resolution geochemical records are presented for cores from two massive Porites corals, located 20 km apart near Marbat on the Arabian Sea coast of southern Oman. We consider four aspects of skeletal chemistry: oxygen and carbon isotopic composition, barium content and the nature and occurence of annual fluorescent bands within the coral skeletons. Coral skeletal ë18O documents variations in sea surface temperature which have regional and basin-wide significance. In particular, the ë18O of coral skeleton precipitated during the period of the NE monsoon is strongly correlated with annual rainfall anomalies in India, whilst that precipitated during the period of the SW monsoon appears to provide information on variability in the strength of coastal upwelling. The stable carbon isotope composition and barium content of these particular corals display strong annual cycles, but do not appear to directly record interannual climatic/oceanographic variability. It is concluded that corals on the coast of southern Oman have great potential to provide high-resolution, century-long records of oceanographic and climatic variability associated with the operation of the monsoon climate system.},
keywords = {Arabian Sea, coral, India, Oman, surface temperature, temperature, Upwelling},
pubstate = {published},
tppubtype = {article}
}
Corals living in the coastal waters of southern Oman experience the influence of the seasonally reversing Asian monsoon system. The objective of the research reported here is to assess the potential for using the skeletal chemistry of these corals to investigate past variability in the monsoon climate. To this end, 20-year long, monthly resolution geochemical records are presented for cores from two massive Porites corals, located 20 km apart near Marbat on the Arabian Sea coast of southern Oman. We consider four aspects of skeletal chemistry: oxygen and carbon isotopic composition, barium content and the nature and occurence of annual fluorescent bands within the coral skeletons. Coral skeletal ë18O documents variations in sea surface temperature which have regional and basin-wide significance. In particular, the ë18O of coral skeleton precipitated during the period of the NE monsoon is strongly correlated with annual rainfall anomalies in India, whilst that precipitated during the period of the SW monsoon appears to provide information on variability in the strength of coastal upwelling. The stable carbon isotope composition and barium content of these particular corals display strong annual cycles, but do not appear to directly record interannual climatic/oceanographic variability. It is concluded that corals on the coast of southern Oman have great potential to provide high-resolution, century-long records of oceanographic and climatic variability associated with the operation of the monsoon climate system.
Bruce, John G,Johnson, Donald R,Kindle, John C
Evidence for eddy formation in the eastern Arabian Sea during the northeast monsoon Journal Article
In: Journal of Geophysical Research: Oceans, vol. 99, no. 59, pp. 7651-7664, 1994, ISBN: 2156-2202.
Abstract | BibTeX | Tags: Arabian Sea, Eddy, India, Laccadive Islands, monsoon, oceanography
@article{,
title = {Evidence for eddy formation in the eastern Arabian Sea during the northeast monsoon},
author = {Bruce, John G,Johnson, Donald R,Kindle, John C},
issn = {2156-2202},
year = {1994},
date = {1994-01-01},
journal = {Journal of Geophysical Research: Oceans},
volume = {99},
number = {59},
pages = {7651-7664},
abstract = {The seasonal formation of a large (500-800 km diameter) anticyclonic eddy
in the upper 300-400 rn of the eastern Arabian Sea during the northeast monsoon
period (December-April) is indicated from hydrographic and satellite altimetry sea level
observations, as well as from numerical model experiments. The center of the eddy
circulation is approximately 10øN, 70øE, just to the west of the north-south Laccadive
Island chain. In this paper the eddy is called the Laccadive High (LH). In some ways
it is a mirrorlike counterpart to the Great Whirl, which develops during the southwest
monsoon off the Somali coast (western Arabian Sea). The LH occurs at the same
latitude but on the opposite side of the basin during the reversed monsoon. It is
different from the Great Whirl, however, in its formation process, its intensity, and its
decay. The hydrographic data obtained from surveys all during a single season give
sufficiently close station spacing to allow reasonable contouring of the geopotential
surfaces and of the properties within and around the LH region with minimum time
aliasing. The Geosat altimeter record extends over 4 years, during which the seasonal
variability of the LH indicates a dynamic relief of approximately 15-20 cm, which is in
good agreement with the hydrographic observations. The altimetry time series also
suggests a westward translation of the LH by January with a subsequent dissipation in
midbasin. The model used is a wind-forced three-layer primitive equation model which
depicts a LH in agreement with the timing, position, and amplitude of both the
hydrographic and altimetric measurements. The numerical simulation includes a
passive tracer located in the western Bay of Bengal; the western advection of the
tracer around the south coasts of Sri Lanka and India in December and January is
consistent with the appearance of low-salinity water observed to extend into the
Arabian Sea during this period. The modeling studies suggest that both local and
remote forcing are important in formation of the LH.},
keywords = {Arabian Sea, Eddy, India, Laccadive Islands, monsoon, oceanography},
pubstate = {published},
tppubtype = {article}
}
The seasonal formation of a large (500-800 km diameter) anticyclonic eddy
in the upper 300-400 rn of the eastern Arabian Sea during the northeast monsoon
period (December-April) is indicated from hydrographic and satellite altimetry sea level
observations, as well as from numerical model experiments. The center of the eddy
circulation is approximately 10øN, 70øE, just to the west of the north-south Laccadive
Island chain. In this paper the eddy is called the Laccadive High (LH). In some ways
it is a mirrorlike counterpart to the Great Whirl, which develops during the southwest
monsoon off the Somali coast (western Arabian Sea). The LH occurs at the same
latitude but on the opposite side of the basin during the reversed monsoon. It is
different from the Great Whirl, however, in its formation process, its intensity, and its
decay. The hydrographic data obtained from surveys all during a single season give
sufficiently close station spacing to allow reasonable contouring of the geopotential
surfaces and of the properties within and around the LH region with minimum time
aliasing. The Geosat altimeter record extends over 4 years, during which the seasonal
variability of the LH indicates a dynamic relief of approximately 15-20 cm, which is in
good agreement with the hydrographic observations. The altimetry time series also
suggests a westward translation of the LH by January with a subsequent dissipation in
midbasin. The model used is a wind-forced three-layer primitive equation model which
depicts a LH in agreement with the timing, position, and amplitude of both the
hydrographic and altimetric measurements. The numerical simulation includes a
passive tracer located in the western Bay of Bengal; the western advection of the
tracer around the south coasts of Sri Lanka and India in December and January is
consistent with the appearance of low-salinity water observed to extend into the
Arabian Sea during this period. The modeling studies suggest that both local and
remote forcing are important in formation of the LH.
in the upper 300-400 rn of the eastern Arabian Sea during the northeast monsoon
period (December-April) is indicated from hydrographic and satellite altimetry sea level
observations, as well as from numerical model experiments. The center of the eddy
circulation is approximately 10øN, 70øE, just to the west of the north-south Laccadive
Island chain. In this paper the eddy is called the Laccadive High (LH). In some ways
it is a mirrorlike counterpart to the Great Whirl, which develops during the southwest
monsoon off the Somali coast (western Arabian Sea). The LH occurs at the same
latitude but on the opposite side of the basin during the reversed monsoon. It is
different from the Great Whirl, however, in its formation process, its intensity, and its
decay. The hydrographic data obtained from surveys all during a single season give
sufficiently close station spacing to allow reasonable contouring of the geopotential
surfaces and of the properties within and around the LH region with minimum time
aliasing. The Geosat altimeter record extends over 4 years, during which the seasonal
variability of the LH indicates a dynamic relief of approximately 15-20 cm, which is in
good agreement with the hydrographic observations. The altimetry time series also
suggests a westward translation of the LH by January with a subsequent dissipation in
midbasin. The model used is a wind-forced three-layer primitive equation model which
depicts a LH in agreement with the timing, position, and amplitude of both the
hydrographic and altimetric measurements. The numerical simulation includes a
passive tracer located in the western Bay of Bengal; the western advection of the
tracer around the south coasts of Sri Lanka and India in December and January is
consistent with the appearance of low-salinity water observed to extend into the
Arabian Sea during this period. The modeling studies suggest that both local and
remote forcing are important in formation of the LH.
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.
Silas,E.G.,Matthew,K.J.
Spatial distribution of Euphausiacea (Crustacea) in the southeastern Arabian Sea Journal Article
In: Journal of the Marine Biological Association of India, vol. 28, no. 230, pp. 1-21, 1986.
Abstract | BibTeX | Tags: abundance, Arabian Sea, Distribution, Euphausiid, India, Oceanic, zooplankton
@article{,
title = {Spatial distribution of Euphausiacea (Crustacea) in the southeastern Arabian Sea},
author = {Silas,E.G.,Matthew,K.J.},
year = {1986},
date = {1986-01-01},
journal = {Journal of the Marine Biological Association of India},
volume = {28},
number = {230},
pages = {1-21},
abstract = {Spatial distribution of euphausiids of the southeastern Arabian Sea (west coast of India including the Lakshadweep Sea) was studied. The Arabian Sea and the Bay of Bengal, closed at their northern parts, present special hydrographical features which influence the distribution and abundance of zooplankton in these areas. Here the l0 degree N latitude is thought to be an effective barrier against he penetration of several oceanic species of euphausiids northwards. This is because of the significant changes in the water quality of N of 10 degree N being influenced by the discharge from major river systems of the Indian sub-continent. The species Thysanopoda monacantha, T. tricuspidata and Stylocheiron maximum, which were believed to be restricted to areas south of 10 degrees N are distributed even further northwards.},
keywords = {abundance, Arabian Sea, Distribution, Euphausiid, India, Oceanic, zooplankton},
pubstate = {published},
tppubtype = {article}
}
Spatial distribution of euphausiids of the southeastern Arabian Sea (west coast of India including the Lakshadweep Sea) was studied. The Arabian Sea and the Bay of Bengal, closed at their northern parts, present special hydrographical features which influence the distribution and abundance of zooplankton in these areas. Here the l0 degree N latitude is thought to be an effective barrier against he penetration of several oceanic species of euphausiids northwards. This is because of the significant changes in the water quality of N of 10 degree N being influenced by the discharge from major river systems of the Indian sub-continent. The species Thysanopoda monacantha, T. tricuspidata and Stylocheiron maximum, which were believed to be restricted to areas south of 10 degrees N are distributed even further northwards.
Lal Mohan,R.S.
Osteology of dolphins Journal Article
In: Proc. Symp. Endangered Mairne Animals and Marine Parks, vol. 1, no. 140, pp. 93-99, 1985.
Abstract | BibTeX | Tags: Arabian Sea, bottlenose dolphin, Common dolphin, gillnet, humpback dolphins, India, Indian Ocean, skull, Spinner dolphin
@article{,
title = {Osteology of dolphins},
author = {Lal Mohan,R.S.},
year = {1985},
date = {1985-01-01},
journal = {Proc. Symp. Endangered Mairne Animals and Marine Parks},
volume = {1},
number = {140},
pages = {93-99},
abstract = {Osteology of four dolphins (Common, Spinner, Bottlenose and Humpback) are studied from the south-west coast of India. The measurements of the skulls are compared with information available from other parts of the world. Specimens were obtained from bycatch in gillnets off the Calicut coast.},
keywords = {Arabian Sea, bottlenose dolphin, Common dolphin, gillnet, humpback dolphins, India, Indian Ocean, skull, Spinner dolphin},
pubstate = {published},
tppubtype = {article}
}
Osteology of four dolphins (Common, Spinner, Bottlenose and Humpback) are studied from the south-west coast of India. The measurements of the skulls are compared with information available from other parts of the world. Specimens were obtained from bycatch in gillnets off the Calicut coast.
Pilleri, G
Cetologische Expedition zum Indus und Persischen Golf und Forschungsreise nach Goa und Thailand im Jahre 1973 Journal Article
In: Investigations on Cetacea, vol. 5, no. 188, pp. 36-38, 1973.
BibTeX | Tags: Arabian Sea, India, Indus Delta, Pakistan, Persian Gulf, Thailand
@article{,
title = {Cetologische Expedition zum Indus und Persischen Golf und Forschungsreise nach Goa und Thailand im Jahre 1973},
author = {Pilleri, G},
year = {1973},
date = {1973-01-01},
journal = {Investigations on Cetacea},
volume = {5},
number = {188},
pages = {36-38},
keywords = {Arabian Sea, India, Indus Delta, Pakistan, Persian Gulf, Thailand},
pubstate = {published},
tppubtype = {article}
}
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.
Brown,S.G.
Whales observed in the Indian Ocean: notes on their distribution Journal Article
In: The Marine Observer, vol. 27, no. 339, pp. 157-165, 1957.
Abstract | BibTeX | Tags: Antarctic, Arabian Sea, Australia, baleen whales, Central Indian Ocean, cetacean, density, Distribution, Gulf of Aden, Humpback Whale, humpback whales, India, Indian Ocean, Oman, population, South Africa, Southern Hemisphere, sperm whale, sperm whales, whale, whales
@article{,
title = {Whales observed in the Indian Ocean: notes on their distribution},
author = {Brown,S.G.},
year = {1957},
date = {1957-01-01},
journal = {The Marine Observer},
volume = {27},
number = {339},
pages = {157-165},
abstract = {The paper provides a summary of the results of a questionnaire put to merchant ships and other vessels, 80 of which provided their track data. These vessels apparently had someone on watch during all daylight hours and reported all their cetacean sightings. The authors feel confident that while some sightings could not be identified to species level, a distinction could be drawn between sperm, humpback and "rorqual" whales. The "search effort" and sightings of the ships are plotted in the paper, with the majority of search effort and a high concentration of sightings occurring in the Gulf of Aden and S coast of Oman. Only two humpback whale sightings are recorded for the Northern Arabian sea - one near the horn of Africa/Somalia, and one near Sharbitat/Likbe. An additional string 4 of humpback whale sightings are recorded off the SW coast of India in the region of the Laccadive Islands.The author himself concludes: "There is apparently no great difference in the overall density of the large whale populations per unit area north and south of the equator. The highest concentrations of whales in the Indian Ocean occur in the Gulf of Aden and its approaches, the Arabian Sea and in the zone between South Africa and Australia. The least concentration is found in the Central Indian Ocean. In summer the concentration of baleen whales in the Antarctic is very many times greater than in the Indian Ocean but there is much less difference in winter . The number of sperm whales in the ocean as a whole seems not to outnumber that of the different species of baleen whales combined. Humpback whales and rorquals are found unexpectedly far north, on the supposition that they all belong to the southern hemisphere populations. Rorquals have been observed right across the 30ø to 40ø S. zone between South Africa and Australia where ships might be expected to intercept them occasionally during their migrations."},
keywords = {Antarctic, Arabian Sea, Australia, baleen whales, Central Indian Ocean, cetacean, density, Distribution, Gulf of Aden, Humpback Whale, humpback whales, India, Indian Ocean, Oman, population, South Africa, Southern Hemisphere, sperm whale, sperm whales, whale, whales},
pubstate = {published},
tppubtype = {article}
}
The paper provides a summary of the results of a questionnaire put to merchant ships and other vessels, 80 of which provided their track data. These vessels apparently had someone on watch during all daylight hours and reported all their cetacean sightings. The authors feel confident that while some sightings could not be identified to species level, a distinction could be drawn between sperm, humpback and "rorqual" whales. The "search effort" and sightings of the ships are plotted in the paper, with the majority of search effort and a high concentration of sightings occurring in the Gulf of Aden and S coast of Oman. Only two humpback whale sightings are recorded for the Northern Arabian sea - one near the horn of Africa/Somalia, and one near Sharbitat/Likbe. An additional string 4 of humpback whale sightings are recorded off the SW coast of India in the region of the Laccadive Islands.The author himself concludes: "There is apparently no great difference in the overall density of the large whale populations per unit area north and south of the equator. The highest concentrations of whales in the Indian Ocean occur in the Gulf of Aden and its approaches, the Arabian Sea and in the zone between South Africa and Australia. The least concentration is found in the Central Indian Ocean. In summer the concentration of baleen whales in the Antarctic is very many times greater than in the Indian Ocean but there is much less difference in winter . The number of sperm whales in the ocean as a whole seems not to outnumber that of the different species of baleen whales combined. Humpback whales and rorquals are found unexpectedly far north, on the supposition that they all belong to the southern hemisphere populations. Rorquals have been observed right across the 30ø to 40ø S. zone between South Africa and Australia where ships might be expected to intercept them occasionally during their migrations."
Sajikumar, Kurichithara K.,Ragesh, Nadakkal,Mohamed, Kolliyil S.
Behaviour of Short-finned Pilot Whales Journal Article
In: Journal of Threatened Taxa, vol. 6, no. 218, pp. 6488-6492, 0000, ISBN: 0974-7907.
Abstract | Links | BibTeX | Tags: Arabian Sea, Globicephala macrorhynchus, India, short-finned pilot whale
@article{,
title = {Behaviour of Short-finned Pilot Whales},
author = {Sajikumar, Kurichithara K.,Ragesh, Nadakkal,Mohamed, Kolliyil S.},
url = {https://threatenedtaxa.org/index.php/JoTT/article/view/1626},
issn = {0974-7907},
journal = {Journal of Threatened Taxa},
volume = {6},
number = {218},
pages = {6488-6492},
abstract = {We report the presence and behaviour of a pod of short-finned pilot whale Globicephala macrorhynchus in the southeastern Arabian Sea. The pod was observed in the southeastern side of Minicoy Island, in the Nine degree channel (09°219′23′′N;74°39′529′′E) on 03.02.2013. Later, on 06.02.2013,the same pod of pilot whales were observed near Kalpeni Island (10°02′402′′N; 73°39′579′′E) 130 km northwest of the previous location. The average length of the whales was estimated as 550 cm and weight as approximately 1200 kg. They were travelling in a northwesterly direction. The pod size of the whales sighted was twelve and several species specific behaviour such as side rolling, spyhopping, lobtailing, peduncle arching and movement patterns such as synchronous travelling and logging could be observed. The occurrence of scars and injuries on the body of four whales in the pod are also reported.},
keywords = {Arabian Sea, Globicephala macrorhynchus, India, short-finned pilot whale},
pubstate = {published},
tppubtype = {article}
}
We report the presence and behaviour of a pod of short-finned pilot whale Globicephala macrorhynchus in the southeastern Arabian Sea. The pod was observed in the southeastern side of Minicoy Island, in the Nine degree channel (09°219′23′′N;74°39′529′′E) on 03.02.2013. Later, on 06.02.2013,the same pod of pilot whales were observed near Kalpeni Island (10°02′402′′N; 73°39′579′′E) 130 km northwest of the previous location. The average length of the whales was estimated as 550 cm and weight as approximately 1200 kg. They were travelling in a northwesterly direction. The pod size of the whales sighted was twelve and several species specific behaviour such as side rolling, spyhopping, lobtailing, peduncle arching and movement patterns such as synchronous travelling and logging could be observed. The occurrence of scars and injuries on the body of four whales in the pod are also reported.