Geographical variation in the body size of adult female sperm whales (Physeter macrocephalus) – an example of McNab’s resource rule?
This study investigates possible regional variations in size composition of adult female sperm whales (Physeter macrocephalus) using data from 3302 pregnant individuals taken on Soviet whaling expeditions to the Southern Hemisphere 1961/62–1974/75. A general linear model (GLM) was used to take the c...
Main Authors: | , , , |
---|---|
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
De Gruyter
2016
|
Subjects: | |
Online Access: | http://hdl.handle.net/11427/22421 https://open.uct.ac.za/bitstream/11427/22421/1/Best_Article_2015.pdf |
id |
ftunivcapetownir:oai:localhost:11427/22421 |
---|---|
record_format |
openpolar |
spelling |
ftunivcapetownir:oai:localhost:11427/22421 2023-05-15T17:59:21+02:00 Geographical variation in the body size of adult female sperm whales (Physeter macrocephalus) – an example of McNab’s resource rule? Best, Peter B Tormosov, Dmitri Brandão, Anabela Mikhalev, Yuri 2016 application/pdf http://hdl.handle.net/11427/22421 https://open.uct.ac.za/bitstream/11427/22421/1/Best_Article_2015.pdf eng eng De Gruyter University of Cape Town Faculty of Science Marine Resource Assessment and Management Group http://hdl.handle.net/11427/22421 https://open.uct.ac.za/bitstream/11427/22421/1/Best_Article_2015.pdf Mammalia https://www.degruyter.com/view/j/mamm?rskey=f0Xkj4&result=254&q= adult female body size growth latitudinal gradient population difference resource rule sperm whale Journal Article 2016 ftunivcapetownir 2022-09-13T05:55:47Z This study investigates possible regional variations in size composition of adult female sperm whales (Physeter macrocephalus) using data from 3302 pregnant individuals taken on Soviet whaling expeditions to the Southern Hemisphere 1961/62–1974/75. A general linear model (GLM) was used to take the covariates of expedition, latitude and ocean basin into account. The average body size decreased from south to north in each ocean basin, with the biggest decrease (about 200 cm) in the Indian Ocean; followed by the Pacific Ocean (about 110 cm), and the Atlantic Ocean (about 80 cm). Independent data confirm the small size of female/immature sperm whales in some tropical areas of the Indian and Pacific Oceans. The mechanism responsible for this geographic variation in sperm whale growth could reflect culturally transmitted differences in foraging behaviour between clans of female/immature sperm whales in response to differing availabilities of prey resources by geographical region – McNab’s resource rule. However there is little available information for such a mechanism to be readily identifiable. Although data for oceanic squids (sperm whale’s main source of food) are lacking, there is evidence that the individual sizes of neritic species are positively correlated with latitude. Hence feeding in equatorial regions may be energetically more demanding due to smaller individual prey size, with consequent effects on growth rate. Article in Journal/Newspaper Physeter macrocephalus Sperm whale University of Cape Town: OpenUCT Indian Pacific |
institution |
Open Polar |
collection |
University of Cape Town: OpenUCT |
op_collection_id |
ftunivcapetownir |
language |
English |
topic |
adult female body size growth latitudinal gradient population difference resource rule sperm whale |
spellingShingle |
adult female body size growth latitudinal gradient population difference resource rule sperm whale Best, Peter B Tormosov, Dmitri Brandão, Anabela Mikhalev, Yuri Geographical variation in the body size of adult female sperm whales (Physeter macrocephalus) – an example of McNab’s resource rule? |
topic_facet |
adult female body size growth latitudinal gradient population difference resource rule sperm whale |
description |
This study investigates possible regional variations in size composition of adult female sperm whales (Physeter macrocephalus) using data from 3302 pregnant individuals taken on Soviet whaling expeditions to the Southern Hemisphere 1961/62–1974/75. A general linear model (GLM) was used to take the covariates of expedition, latitude and ocean basin into account. The average body size decreased from south to north in each ocean basin, with the biggest decrease (about 200 cm) in the Indian Ocean; followed by the Pacific Ocean (about 110 cm), and the Atlantic Ocean (about 80 cm). Independent data confirm the small size of female/immature sperm whales in some tropical areas of the Indian and Pacific Oceans. The mechanism responsible for this geographic variation in sperm whale growth could reflect culturally transmitted differences in foraging behaviour between clans of female/immature sperm whales in response to differing availabilities of prey resources by geographical region – McNab’s resource rule. However there is little available information for such a mechanism to be readily identifiable. Although data for oceanic squids (sperm whale’s main source of food) are lacking, there is evidence that the individual sizes of neritic species are positively correlated with latitude. Hence feeding in equatorial regions may be energetically more demanding due to smaller individual prey size, with consequent effects on growth rate. |
format |
Article in Journal/Newspaper |
author |
Best, Peter B Tormosov, Dmitri Brandão, Anabela Mikhalev, Yuri |
author_facet |
Best, Peter B Tormosov, Dmitri Brandão, Anabela Mikhalev, Yuri |
author_sort |
Best, Peter B |
title |
Geographical variation in the body size of adult female sperm whales (Physeter macrocephalus) – an example of McNab’s resource rule? |
title_short |
Geographical variation in the body size of adult female sperm whales (Physeter macrocephalus) – an example of McNab’s resource rule? |
title_full |
Geographical variation in the body size of adult female sperm whales (Physeter macrocephalus) – an example of McNab’s resource rule? |
title_fullStr |
Geographical variation in the body size of adult female sperm whales (Physeter macrocephalus) – an example of McNab’s resource rule? |
title_full_unstemmed |
Geographical variation in the body size of adult female sperm whales (Physeter macrocephalus) – an example of McNab’s resource rule? |
title_sort |
geographical variation in the body size of adult female sperm whales (physeter macrocephalus) – an example of mcnab’s resource rule? |
publisher |
De Gruyter |
publishDate |
2016 |
url |
http://hdl.handle.net/11427/22421 https://open.uct.ac.za/bitstream/11427/22421/1/Best_Article_2015.pdf |
geographic |
Indian Pacific |
geographic_facet |
Indian Pacific |
genre |
Physeter macrocephalus Sperm whale |
genre_facet |
Physeter macrocephalus Sperm whale |
op_source |
Mammalia https://www.degruyter.com/view/j/mamm?rskey=f0Xkj4&result=254&q= |
op_relation |
http://hdl.handle.net/11427/22421 https://open.uct.ac.za/bitstream/11427/22421/1/Best_Article_2015.pdf |
_version_ |
1766168157342400512 |