Mehta,A.V.
How important are baleen whales as prey for killer whales (Orcinus orca) in high-latitude waters? PhD Thesis
2004.
Abstract | BibTeX | Tags: Alaska, Antarctic, Atlantic, Australia, baleen whales, Blue whale, blue whales, Gulf of Maine, Humpback Whale, humpback whales, killer whale, killer whales, New Caledonia, New Zealand, North Atlantic, North Atlantic right whale, North Pacific, Oman, Orca, Orcinus orca, population, prey, pygmy blue whale, Pygmy blue whales, right whale, right whales, whale, whales, whaling
@phdthesis{,
title = {How important are baleen whales as prey for killer whales (Orcinus orca) in high-latitude waters?},
author = {Mehta,A.V.},
year = {2004},
date = {2004-01-01},
number = {403},
pages = {1-15},
publisher = {Boston University},
abstract = {Data on humpback whales were collected from twenty-one regions: eleven in the North Atlantic and three in the North Pacific, as well as American Samoa, Vava'u (Tonga), New Zealand, New Caledonia, western Australia, the Antarctic Peninsula, and Oman. The other species and subspecies included in this project were sampled from a single population each (Fig. 1): North Atlantic right whales, blue whales off southeastern Australia, and pygmy blue whales (Balaenoptera musculus brevicauda) off western Australia. The proportion of whales in different sampling regions bearing rake marks ranged from 0% to over 40%. The Gulf of Maine population had a scarring rate of 9.9-11%, while SW Alaska had a rate of 21.1 to 21.9%. Oman had a rate of 9.1% (3 of 33 animals). The highest rate of scarring was the "Mexico" population with a scarring rate of over 40%. Of those scarred animals with multi-year sighting histories, 82.8% to 100% had those scars the first time they were sighted. Of the total number of whales sampled from these regions, 0% to only 4.8% acquired new or additional rake marks after their first sighting, supporting the hypothesis that most whales aquire their scars as calves, and that adult baleen whales do not constitute a major prey source for killer whales.Overall, the present study suggests that the hypothesis presented by Springer et al. (2003) - that killer whales in the North Pacific were forced by industrial whaling to switch prey from baleen whales to pinnipeds and sea otters - is untenable.},
keywords = {Alaska, Antarctic, Atlantic, Australia, baleen whales, Blue whale, blue whales, Gulf of Maine, Humpback Whale, humpback whales, killer whale, killer whales, New Caledonia, New Zealand, North Atlantic, North Atlantic right whale, North Pacific, Oman, Orca, Orcinus orca, population, prey, pygmy blue whale, Pygmy blue whales, right whale, right whales, whale, whales, whaling},
pubstate = {published},
tppubtype = {phdthesis}
}
Data on humpback whales were collected from twenty-one regions: eleven in the North Atlantic and three in the North Pacific, as well as American Samoa, Vava'u (Tonga), New Zealand, New Caledonia, western Australia, the Antarctic Peninsula, and Oman. The other species and subspecies included in this project were sampled from a single population each (Fig. 1): North Atlantic right whales, blue whales off southeastern Australia, and pygmy blue whales (Balaenoptera musculus brevicauda) off western Australia. The proportion of whales in different sampling regions bearing rake marks ranged from 0% to over 40%. The Gulf of Maine population had a scarring rate of 9.9-11%, while SW Alaska had a rate of 21.1 to 21.9%. Oman had a rate of 9.1% (3 of 33 animals). The highest rate of scarring was the "Mexico" population with a scarring rate of over 40%. Of those scarred animals with multi-year sighting histories, 82.8% to 100% had those scars the first time they were sighted. Of the total number of whales sampled from these regions, 0% to only 4.8% acquired new or additional rake marks after their first sighting, supporting the hypothesis that most whales aquire their scars as calves, and that adult baleen whales do not constitute a major prey source for killer whales.Overall, the present study suggests that the hypothesis presented by Springer et al. (2003) - that killer whales in the North Pacific were forced by industrial whaling to switch prey from baleen whales to pinnipeds and sea otters - is untenable.
Corkeron,P.J.,Connor,R.C.
Why do baleen whales migrate? Journal Article
In: Marine Mammal Science, vol. 15, no. 76, pp. 1228-1245, 1999.
Abstract | BibTeX | Tags: abundance, Distribution, killer whale, killer whales, migration, mysticetes, Orca, predation
@article{,
title = {Why do baleen whales migrate?},
author = {Corkeron,P.J.,Connor,R.C.},
year = {1999},
date = {1999-01-01},
journal = {Marine Mammal Science},
volume = {15},
number = {76},
pages = {1228-1245},
abstract = {The annual migrations of baleen whales are a conspicuous, but unexplained feature of their behavioural repertoire. Some hypotheses offered to explain whale migration focus on direct benefits to the calf (thermoregulation, calm water) and some do not (resource tracking, and the "evolutionary holdover" hypothesis). Here we suggest that a major selective advantage to migrating pregnant female baleen whales is a reduced risk of killer whale predation on their newborn calves in low-latitude waters. Killer whale abundance in high latitudes is substantially greater than that in lower latitudes, and most killer whales do not appear to migrate with baleen whales. We suggest that the distribution of killer whales is determined more by their primary marine mammal prey, pinnipeds, and that following the baleen whale migrations would remove them from their pinnipeds prey. There are problems with all current hypotheses, most of which stem from a lack of directed research. We explore variation in migratory habits between species, populations, and individuals that may provide a "natural laboratory" for discriminating among the competing hypotheses. The authors specifically recommend more detailed study of non-migrating populations, such as the Arabian Sea population of humpback whales.},
keywords = {abundance, Distribution, killer whale, killer whales, migration, mysticetes, Orca, predation},
pubstate = {published},
tppubtype = {article}
}
The annual migrations of baleen whales are a conspicuous, but unexplained feature of their behavioural repertoire. Some hypotheses offered to explain whale migration focus on direct benefits to the calf (thermoregulation, calm water) and some do not (resource tracking, and the "evolutionary holdover" hypothesis). Here we suggest that a major selective advantage to migrating pregnant female baleen whales is a reduced risk of killer whale predation on their newborn calves in low-latitude waters. Killer whale abundance in high latitudes is substantially greater than that in lower latitudes, and most killer whales do not appear to migrate with baleen whales. We suggest that the distribution of killer whales is determined more by their primary marine mammal prey, pinnipeds, and that following the baleen whale migrations would remove them from their pinnipeds prey. There are problems with all current hypotheses, most of which stem from a lack of directed research. We explore variation in migratory habits between species, populations, and individuals that may provide a "natural laboratory" for discriminating among the competing hypotheses. The authors specifically recommend more detailed study of non-migrating populations, such as the Arabian Sea population of humpback whales.
Harwood,J.
Observations of cetaceans in the Arabian Sea, November - December 1980 Technical Report
no. 384, 1980.
Abstract | BibTeX | Tags: Arabian Sea, cetacean, cetaceans, dolphin, dolphins, Gulf of Oman, killer whale, killer whales, Oman, Spinner dolphin, whale, whales
@techreport{,
title = {Observations of cetaceans in the Arabian Sea, November - December 1980
},
author = {Harwood,J.},
year = {1980},
date = {1980-01-01},
number = {384},
pages = {1-7},
publisher = {Sea Mammal Research Unit, Cambridge},
abstract = {This is a brief report of cetacean sightings made during the voyage of the sailing ship SOHAR (a 26m long reconstruction of a ninth century Arab dhow from Muscat to Calicut, from 23 Nov to 21 Dec.1980. The cruise covered only the Gulf of Oman Coast of Oman from roughly Muscat to Tiwi, and then head across to the Indian Sub-continent. Only 26 sightings were made during intermittent watches. Sightings off Oman included pygmy killer whales (uncertain ID), two groups of unidentified dolphins and spinner dolphins.},
keywords = {Arabian Sea, cetacean, cetaceans, dolphin, dolphins, Gulf of Oman, killer whale, killer whales, Oman, Spinner dolphin, whale, whales},
pubstate = {published},
tppubtype = {techreport}
}
This is a brief report of cetacean sightings made during the voyage of the sailing ship SOHAR (a 26m long reconstruction of a ninth century Arab dhow from Muscat to Calicut, from 23 Nov to 21 Dec.1980. The cruise covered only the Gulf of Oman Coast of Oman from roughly Muscat to Tiwi, and then head across to the Indian Sub-continent. Only 26 sightings were made during intermittent watches. Sightings off Oman included pygmy killer whales (uncertain ID), two groups of unidentified dolphins and spinner dolphins.
Harwood,J.
Observations of cetaceans in the Arabian Sea, November - December 1980 Technical Report
no. 384, 1980.
Abstract | BibTeX | Tags: Arabian Sea, cetacean, cetaceans, dolphin, dolphins, Gulf of Oman, killer whale, killer whales, Oman, Spinner dolphin, whale, whales
@techreport{,
title = {Observations of cetaceans in the Arabian Sea, November - December 1980
},
author = {Harwood,J.},
year = {1980},
date = {1980-01-01},
number = {384},
pages = {1-7},
publisher = {Sea Mammal Research Unit, Cambridge},
abstract = {This is a brief report of cetacean sightings made during the voyage of the sailing ship SOHAR (a 26m long reconstruction of a ninth century Arab dhow from Muscat to Calicut, from 23 Nov to 21 Dec.1980. The cruise covered only the Gulf of Oman Coast of Oman from roughly Muscat to Tiwi, and then head across to the Indian Sub-continent. Only 26 sightings were made during intermittent watches. Sightings off Oman included pygmy killer whales (uncertain ID), two groups of unidentified dolphins and spinner dolphins.},
keywords = {Arabian Sea, cetacean, cetaceans, dolphin, dolphins, Gulf of Oman, killer whale, killer whales, Oman, Spinner dolphin, whale, whales},
pubstate = {published},
tppubtype = {techreport}
}
This is a brief report of cetacean sightings made during the voyage of the sailing ship SOHAR (a 26m long reconstruction of a ninth century Arab dhow from Muscat to Calicut, from 23 Nov to 21 Dec.1980. The cruise covered only the Gulf of Oman Coast of Oman from roughly Muscat to Tiwi, and then head across to the Indian Sub-continent. Only 26 sightings were made during intermittent watches. Sightings off Oman included pygmy killer whales (uncertain ID), two groups of unidentified dolphins and spinner dolphins.
Harwood,J.
Observations of cetaceans in the Arabian Sea, November - December 1980 Technical Report
no. 384, 1980.
Abstract | BibTeX | Tags: Arabian Sea, cetacean, cetaceans, dolphin, dolphins, Gulf of Oman, killer whale, killer whales, Oman, Spinner dolphin, whale, whales
@techreport{,
title = {Observations of cetaceans in the Arabian Sea, November - December 1980
},
author = {Harwood,J.},
year = {1980},
date = {1980-01-01},
number = {384},
pages = {1-7},
publisher = {Sea Mammal Research Unit, Cambridge},
abstract = {This is a brief report of cetacean sightings made during the voyage of the sailing ship SOHAR (a 26m long reconstruction of a ninth century Arab dhow from Muscat to Calicut, from 23 Nov to 21 Dec.1980. The cruise covered only the Gulf of Oman Coast of Oman from roughly Muscat to Tiwi, and then head across to the Indian Sub-continent. Only 26 sightings were made during intermittent watches. Sightings off Oman included pygmy killer whales (uncertain ID), two groups of unidentified dolphins and spinner dolphins.},
keywords = {Arabian Sea, cetacean, cetaceans, dolphin, dolphins, Gulf of Oman, killer whale, killer whales, Oman, Spinner dolphin, whale, whales},
pubstate = {published},
tppubtype = {techreport}
}
This is a brief report of cetacean sightings made during the voyage of the sailing ship SOHAR (a 26m long reconstruction of a ninth century Arab dhow from Muscat to Calicut, from 23 Nov to 21 Dec.1980. The cruise covered only the Gulf of Oman Coast of Oman from roughly Muscat to Tiwi, and then head across to the Indian Sub-continent. Only 26 sightings were made during intermittent watches. Sightings off Oman included pygmy killer whales (uncertain ID), two groups of unidentified dolphins and spinner dolphins.
Harwood,J.
Observations of cetaceans in the Arabian Sea, November - December 1980 Technical Report
no. 384, 1980.
Abstract | BibTeX | Tags: Arabian Sea, cetacean, cetaceans, dolphin, dolphins, Gulf of Oman, killer whale, killer whales, Oman, Spinner dolphin, whale, whales
@techreport{,
title = {Observations of cetaceans in the Arabian Sea, November - December 1980
},
author = {Harwood,J.},
year = {1980},
date = {1980-01-01},
number = {384},
pages = {1-7},
publisher = {Sea Mammal Research Unit, Cambridge},
abstract = {This is a brief report of cetacean sightings made during the voyage of the sailing ship SOHAR (a 26m long reconstruction of a ninth century Arab dhow from Muscat to Calicut, from 23 Nov to 21 Dec.1980. The cruise covered only the Gulf of Oman Coast of Oman from roughly Muscat to Tiwi, and then head across to the Indian Sub-continent. Only 26 sightings were made during intermittent watches. Sightings off Oman included pygmy killer whales (uncertain ID), two groups of unidentified dolphins and spinner dolphins.},
keywords = {Arabian Sea, cetacean, cetaceans, dolphin, dolphins, Gulf of Oman, killer whale, killer whales, Oman, Spinner dolphin, whale, whales},
pubstate = {published},
tppubtype = {techreport}
}
This is a brief report of cetacean sightings made during the voyage of the sailing ship SOHAR (a 26m long reconstruction of a ninth century Arab dhow from Muscat to Calicut, from 23 Nov to 21 Dec.1980. The cruise covered only the Gulf of Oman Coast of Oman from roughly Muscat to Tiwi, and then head across to the Indian Sub-continent. Only 26 sightings were made during intermittent watches. Sightings off Oman included pygmy killer whales (uncertain ID), two groups of unidentified dolphins and spinner dolphins.