Best,P.B.
Distribution and population separation of Bryde's whale Balaenoptera edeni off southern Africa Journal Article
In: Marine Ecology Progress Series, vol. 220, no. 44, pp. 277-289, 2001.
Abstract | BibTeX | Tags: Arabian Sea, Bryde's whale, Distribution, Indian Ocean, length, Madagascar, migration, population characteristics, reproduction, sexual maturity, South Africa, whaling
@article{,
title = {Distribution and population separation of Bryde's whale Balaenoptera edeni off southern Africa},
author = {Best,P.B.},
year = {2001},
date = {2001-01-01},
journal = {Marine Ecology Progress Series},
volume = {220},
number = {44},
pages = {277-289},
abstract = {A review of available catch and biological data suggests that there are 3 populations of Bryde's whales in the Southern African region. An inshore population (the South African Inshore stock) occurs over hte continental shelf of South Africa, south of about 30§ S and seems to be non-migratory, although there is a movement up the west coast in winter. A pelagic population (the South-east Atlantic Stock) occurs on the west coast of southern Africa, ranging from equatorial regions to about 34§ S, and appears to migrate north in autumn and south in spring. Whales from the Southeast Atlantic Stock differ from the South African Inshore Stock in size, scarring, baleen shape, seasonality of reproduction, fecundity and prey types. both occured in the west coast whaling ground off Donkergat, but with differing seasonalities and distributions from the coast. Bryde's whales are rare on the east coast of southern Africa, but are found in summer in some numbers south of Madagascar. Whales from this population are clearly smaller than those from the Southeast Atlantic Stock, but are similar in size to, or even smaller than, those from teh South African Inshore stock. Their external appearance is unknown, but they differ in prey type from South African Inshore stock, and because of a clear discontinuity in distribution, it is believed that they form a third (pelagic) population (the Southwest Indian Ocean Sstock). this population may or may not move normt as far as the Seychelles in winter, but seems to be separate from Bryde's whales in the Arabian Sea. From their size composition, length at sexual maturity and infrequent capture, Bryde's whales taken at Durban may have repasented strays from ei ther ht eh South African Inshore Stock or the Southwest Indian Ocean Stock, and recorded stomach contents also indicate prey ty pes commn toe either stock. The unusual degree of population differentiation shown by Bryde's whales may be a consequence of hteir limited seasonal migrations and apparent resource partitioning.},
keywords = {Arabian Sea, Bryde's whale, Distribution, Indian Ocean, length, Madagascar, migration, population characteristics, reproduction, sexual maturity, South Africa, whaling},
pubstate = {published},
tppubtype = {article}
}
A review of available catch and biological data suggests that there are 3 populations of Bryde's whales in the Southern African region. An inshore population (the South African Inshore stock) occurs over hte continental shelf of South Africa, south of about 30§ S and seems to be non-migratory, although there is a movement up the west coast in winter. A pelagic population (the South-east Atlantic Stock) occurs on the west coast of southern Africa, ranging from equatorial regions to about 34§ S, and appears to migrate north in autumn and south in spring. Whales from the Southeast Atlantic Stock differ from the South African Inshore Stock in size, scarring, baleen shape, seasonality of reproduction, fecundity and prey types. both occured in the west coast whaling ground off Donkergat, but with differing seasonalities and distributions from the coast. Bryde's whales are rare on the east coast of southern Africa, but are found in summer in some numbers south of Madagascar. Whales from this population are clearly smaller than those from the Southeast Atlantic Stock, but are similar in size to, or even smaller than, those from teh South African Inshore stock. Their external appearance is unknown, but they differ in prey type from South African Inshore stock, and because of a clear discontinuity in distribution, it is believed that they form a third (pelagic) population (the Southwest Indian Ocean Sstock). this population may or may not move normt as far as the Seychelles in winter, but seems to be separate from Bryde's whales in the Arabian Sea. From their size composition, length at sexual maturity and infrequent capture, Bryde's whales taken at Durban may have repasented strays from ei ther ht eh South African Inshore Stock or the Southwest Indian Ocean Stock, and recorded stomach contents also indicate prey ty pes commn toe either stock. The unusual degree of population differentiation shown by Bryde's whales may be a consequence of hteir limited seasonal migrations and apparent resource partitioning.
Sherry,N.D.,Wood,A.M.
Phycoerythrin-containing picocyanobacteria in the Arabian Sea in February 1995: diel patterns, spatial variability, and growth rates Journal Article
In: Deep-Sea Research Part II, vol. 48 , no. 225, pp. 1263-1283, 2001.
Abstract | BibTeX | Tags: abundance, Arabian Sea, depth, diel, growth, length, population, survey
@article{,
title = {Phycoerythrin-containing picocyanobacteria in the Arabian Sea in February 1995: diel patterns, spatial variability, and growth rates},
author = {Sherry,N.D.,Wood,A.M.},
year = {2001},
date = {2001-01-01},
journal = {Deep-Sea Research Part II},
volume = {48 },
number = {225},
pages = {1263-1283},
abstract = {The abundance of phycoerythrin-containing picocyanobacteria in the surface mixed layer was measured both along-shore and offshore between 8 and 23 February 1995 in the Northwestern Arabian Sea. Water samples from 3m depth were taken at 2-h intervals and picocyanobacterial abundance and frequency of dividing cells were determined by epifluorescence microscopy. Cell counts showed an average diel change from a mid-day minimum of ~50'103 cells ml-1 to an evening maximum of ~180'103 cells ml-1. The diel change was greater than the differences observed between physically and spatially discrete water masses. By counting the frequency of dividing cells (FDC) and using a novel approach to estimating the length of time required to complete cell division, growth and loss rates were both estimated to be ~2.9 d-1 with daily turnover being 140% of the mean standing stock. If differences in the intrinsic population growth rate (æ) and the net rate of change in cell number (r) are assumed to be due to grazing, then grazing occurred throughout the day at a relatively constant rate (reflecting phytoplankton loss rates of ~0.12 h-1). Cell division rates peaked in the late afternoon and early evening. FDC decreased throughout the night, suggesting that dark-inhibition of cell division is weak or nonexistent in the picocyanobacteria we studied. While all cell types included in this study would be identified as Synechococcus by flow cytometry because they were small unicells with bright phycoerythrin fluorescence, morphological variability suggests that the community was actually taxonomically diverse and included cells other than Synechococcus, including Synechocystis. Despite this diversity, the strong diel patterns we observed persisted throughout the study region, suggesting that great care should be taken when interpreting picocyanobacterial survey data and experimental results that do not account for the e!ects of time-of-day.},
keywords = {abundance, Arabian Sea, depth, diel, growth, length, population, survey},
pubstate = {published},
tppubtype = {article}
}
The abundance of phycoerythrin-containing picocyanobacteria in the surface mixed layer was measured both along-shore and offshore between 8 and 23 February 1995 in the Northwestern Arabian Sea. Water samples from 3m depth were taken at 2-h intervals and picocyanobacterial abundance and frequency of dividing cells were determined by epifluorescence microscopy. Cell counts showed an average diel change from a mid-day minimum of ~50'103 cells ml-1 to an evening maximum of ~180'103 cells ml-1. The diel change was greater than the differences observed between physically and spatially discrete water masses. By counting the frequency of dividing cells (FDC) and using a novel approach to estimating the length of time required to complete cell division, growth and loss rates were both estimated to be ~2.9 d-1 with daily turnover being 140% of the mean standing stock. If differences in the intrinsic population growth rate (æ) and the net rate of change in cell number (r) are assumed to be due to grazing, then grazing occurred throughout the day at a relatively constant rate (reflecting phytoplankton loss rates of ~0.12 h-1). Cell division rates peaked in the late afternoon and early evening. FDC decreased throughout the night, suggesting that dark-inhibition of cell division is weak or nonexistent in the picocyanobacteria we studied. While all cell types included in this study would be identified as Synechococcus by flow cytometry because they were small unicells with bright phycoerythrin fluorescence, morphological variability suggests that the community was actually taxonomically diverse and included cells other than Synechococcus, including Synechocystis. Despite this diversity, the strong diel patterns we observed persisted throughout the study region, suggesting that great care should be taken when interpreting picocyanobacterial survey data and experimental results that do not account for the e!ects of time-of-day.
Burkill,P.H.
Arabesque: An overview Journal Article
In: Deep-Sea Research Part II, vol. 46, no. 340, pp. 529-547, 1999.
Abstract | BibTeX | Tags: Arabian Sea, Gulf of Oman, length, Oceanic, oceanography, Oman, Upwelling
@article{,
title = {Arabesque: An overview},
author = {Burkill,P.H.},
year = {1999},
date = {1999-01-01},
journal = {Deep-Sea Research Part II},
volume = {46},
number = {340},
pages = {529-547},
abstract = {This special issue reports the results of ARABESQUE, a UK-led, international programme of upper-ocean biogeochemistry in the Arabian Sea region, conducted during two contrasting seasons. The seasons studied here were the waning of the southwest monsoon in August/September and the intermonsoon-northeast monsoon transition in November/December 1994. Biogeochemical studies were carried out along three transects in the Gulf of Oman and the Arabian Sea. the main ARABESQUE transect, 1590km in length, lay orthagonal to the southern Oman coast and spanned a range of conditions that encompassed coastal seasonal upwelling through to oceanic aseasonal oligotrophy of the central Arabian Sea. Surface mixed-layer hydrography, PAR, wind speed and direction fields and research results obtained during two seasonal studies are summarised in this paper which also serves and an introductory overview to ARABESQUE.},
keywords = {Arabian Sea, Gulf of Oman, length, Oceanic, oceanography, Oman, Upwelling},
pubstate = {published},
tppubtype = {article}
}
This special issue reports the results of ARABESQUE, a UK-led, international programme of upper-ocean biogeochemistry in the Arabian Sea region, conducted during two contrasting seasons. The seasons studied here were the waning of the southwest monsoon in August/September and the intermonsoon-northeast monsoon transition in November/December 1994. Biogeochemical studies were carried out along three transects in the Gulf of Oman and the Arabian Sea. the main ARABESQUE transect, 1590km in length, lay orthagonal to the southern Oman coast and spanned a range of conditions that encompassed coastal seasonal upwelling through to oceanic aseasonal oligotrophy of the central Arabian Sea. Surface mixed-layer hydrography, PAR, wind speed and direction fields and research results obtained during two seasonal studies are summarised in this paper which also serves and an introductory overview to ARABESQUE.
Van Waerebeek,K.,Gallagher,M.,Baldwin,R.,Papastavrou,V.,Al-Lawati,S.M.
Morphology and distribution of the spinner dolphin, Stenella longirostris, rough-toothed dolphin, Steno brednanensis and melon-headed whale, Peponocephala electra, from waters off the Sultanate of Oman Journal Article
In: The Journal of Cetacean Research and Management, vol. 1, no. 491, pp. 167-177, 1999.
Abstract | BibTeX | Tags: Distribution, Indian Ocean, length, melon-headed whale, morphometrics, Oman, rough-toothed dolphin, Spinner dolphin, Stock identity, taxonomy
@article{,
title = {Morphology and distribution of the spinner dolphin, Stenella longirostris, rough-toothed dolphin, Steno brednanensis and melon-headed whale, Peponocephala electra, from waters off the Sultanate of Oman},
author = {Van Waerebeek,K.,Gallagher,M.,Baldwin,R.,Papastavrou,V.,Al-Lawati,S.M.},
year = {1999},
date = {1999-01-01},
journal = {The Journal of Cetacean Research and Management},
volume = {1},
number = {491},
pages = {167-177},
abstract = {Two previously mis-identified specimens at the Oman Natural History Museum are re-identified as a melon-headed whale and a rough-toothed dolphin. Body lengths of adult male spinner dolphins were smaller than any known stock of spinner dolphins except the dwarf forms in Thailand and Australia and skulls were indistinguishable from those of the eastern spinner dolphins (S.l. orientalis). Two colour morphs of spinner dolphins were observed. The paper concludes that Oman spinner dolphins should be treated as a discrete population, morphologically distinct from all known spinner dolphin sub-species.},
keywords = {Distribution, Indian Ocean, length, melon-headed whale, morphometrics, Oman, rough-toothed dolphin, Spinner dolphin, Stock identity, taxonomy},
pubstate = {published},
tppubtype = {article}
}
Two previously mis-identified specimens at the Oman Natural History Museum are re-identified as a melon-headed whale and a rough-toothed dolphin. Body lengths of adult male spinner dolphins were smaller than any known stock of spinner dolphins except the dwarf forms in Thailand and Australia and skulls were indistinguishable from those of the eastern spinner dolphins (S.l. orientalis). Two colour morphs of spinner dolphins were observed. The paper concludes that Oman spinner dolphins should be treated as a discrete population, morphologically distinct from all known spinner dolphin sub-species.
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.
Mikhalev,Y.A.
Pygmy blue whales of the Northern-Western Indian Ocean Technical Report
no. 405, 1996.
Abstract | BibTeX | Tags: Blue whale, blue whales, Distribution, embryo growth rate, Indian Ocean, length, maturity coming, Northern-Western Indian Ocean, population, pregnancy duration, productivity, pygmy blue whale, Pygmy blue whales, whale, whales, whaling
@techreport{,
title = {Pygmy blue whales of the Northern-Western Indian Ocean},
author = {Mikhalev,Y.A.},
year = {1996},
date = {1996-01-01},
journal = {Document presented to the 48th meeting of the International Whaling Commission},
volume = {SC/48/SH30},
number = {405},
pages = {1-30},
abstract = {The biological characteristic of pygmy blue whale population of the northern-western Indian Ocean according data of whaling results of Slava for seasons 1963/66 and Sovetskaya Ukraina for seasons 1964/67 is given. During period from the end of October to the second half of December pygmy blue whales form in this region four accumulations: Aden-Oman;Pakistan-India; Lacshadweep-Maldives and Equator-Seychelles. The life of the population is provided by high feed productivity of the region. 1294 whales with length from 12.5 m to 24.0 m were taken. The mean length of males was 19.3 m; females - 19.4 m. The males tend to become mature at length 19.0 m and width of testicles 18 - 20 kg; females - at length 21.0 m. The pregnant females form 41.3% from mature ones. The rate of embryo growth is satisfactory described by monoparabola L = 5.98(t - 20.5)1.90The mean new born whale length is 5.5 - 5.6 m. The peak of two seasons of mating are at May and November, the peaks of births - at April and October. The pregnancy is 10.5 - 11.0 months long. The re productivity of pygmy blue whales are low - one new born whales per 2.5 year.},
keywords = {Blue whale, blue whales, Distribution, embryo growth rate, Indian Ocean, length, maturity coming, Northern-Western Indian Ocean, population, pregnancy duration, productivity, pygmy blue whale, Pygmy blue whales, whale, whales, whaling},
pubstate = {published},
tppubtype = {techreport}
}
The biological characteristic of pygmy blue whale population of the northern-western Indian Ocean according data of whaling results of Slava for seasons 1963/66 and Sovetskaya Ukraina for seasons 1964/67 is given. During period from the end of October to the second half of December pygmy blue whales form in this region four accumulations: Aden-Oman;Pakistan-India; Lacshadweep-Maldives and Equator-Seychelles. The life of the population is provided by high feed productivity of the region. 1294 whales with length from 12.5 m to 24.0 m were taken. The mean length of males was 19.3 m; females - 19.4 m. The males tend to become mature at length 19.0 m and width of testicles 18 - 20 kg; females - at length 21.0 m. The pregnant females form 41.3% from mature ones. The rate of embryo growth is satisfactory described by monoparabola L = 5.98(t - 20.5)1.90The mean new born whale length is 5.5 - 5.6 m. The peak of two seasons of mating are at May and November, the peaks of births - at April and October. The pregnancy is 10.5 - 11.0 months long. The re productivity of pygmy blue whales are low - one new born whales per 2.5 year.