Southern right whale (Eubalaena australis) body condition and glucocorticoid levels at the South Africa breeding ground
Southern right whales (Eubalaena australis) in South Africa have been extensively studied since 1979 through annual photo-identification surveys. The resulting database revealed an increased rate of reproductive failure in the last decade. As reproductive success is mediated through body condition,...
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International Whaling Commission
2021
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Online Access: | https://pure.au.dk/portal/en/publications/dabf566e-57d1-4b85-be0f-1e57f74c42a6 https://archive.iwc.int/pages/view.php?search=&k=d001be2e01&modal=&display=list&order_by=field74&offset=0&per_page=240&archive=&sort=DESC&restypes=&recentdaylimit=&foredit=&ref=19081 |
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ftuniaarhuspubl:oai:pure.atira.dk:publications/dabf566e-57d1-4b85-be0f-1e57f74c42a6 2024-05-19T07:49:01+00:00 Southern right whale (Eubalaena australis) body condition and glucocorticoid levels at the South Africa breeding ground Thavar, Terriann Christiansen, Fredrik Oscar Ganswindt, Andre Sironi, Mariano Uhart, Marcela Bejder, Lars Vermeulen, Els 2021 https://pure.au.dk/portal/en/publications/dabf566e-57d1-4b85-be0f-1e57f74c42a6 https://archive.iwc.int/pages/view.php?search=&k=d001be2e01&modal=&display=list&order_by=field74&offset=0&per_page=240&archive=&sort=DESC&restypes=&recentdaylimit=&foredit=&ref=19081 dan dan International Whaling Commission https://pure.au.dk/portal/en/publications/dabf566e-57d1-4b85-be0f-1e57f74c42a6 info:eu-repo/semantics/openAccess Thavar , T , Christiansen , F O , Ganswindt , A , Sironi , M , Uhart , M , Bejder , L & Vermeulen , E 2021 , Southern right whale (Eubalaena australis) body condition and glucocorticoid levels at the South Africa breeding ground . Reports of International Whaling Commission , bind SC/68C/SH/08 , International Whaling Commission . < https://archive.iwc.int/pages/view.php?search=&k=d001be2e01&modal=&display=list&order_by=field74&offset=0&per_page=240&archive=&sort=DESC&restypes=&recentdaylimit=&foredit=&ref=19081 > book 2021 ftuniaarhuspubl 2024-05-01T23:48:43Z Southern right whales (Eubalaena australis) in South Africa have been extensively studied since 1979 through annual photo-identification surveys. The resulting database revealed an increased rate of reproductive failure in the last decade. As reproductive success is mediated through body condition, this study aimed to assess the body condition and physiological indicators of stress of southern right whales on the South Africa breeding ground at present, and compare it to historical data and other populations. For this, aerial photographs of southern right whales were collected using an unmanned aerial vehicle in September 2019 from which body condition was assessed. Additionally, blubber biopsy samples were collected for glucocorticoid (GC) analysis and compared to the body condition estimates of individual whales. To assess temporal change, analogue aerial photographs taken in coastal South Africa in 1988 and 1989 were selected and digitized for body condition measurements, and compared to the 2019 data set. To determine population differences in body condition, the 2019 data set was compared to body condition data from breeding grounds in Argentina and Australia collected the same year. We found a positive relationship between body condition of lactating southern right whales of the South African population and their blubber GC levels, albeit in a small sample size. The temporal comparison revealed a 24% (SE=5.31) decrease in body condition between 2019 and 1988/1989. Furthermore, lactating females in South Africa were in significantly poorer condition compared to those in Australia and Argentina, at a magnitude of -8.1% (SE=3.07) and -7.1% (SE=3.31), respectively. The reduced maternal body condition in the South African population of southern right whales is of grave concern, as it is likely the main reason behind the reduced reproductive success that is decelerating population recovery. Book Southern Right Whale Aarhus University: Research |
institution |
Open Polar |
collection |
Aarhus University: Research |
op_collection_id |
ftuniaarhuspubl |
language |
Danish |
description |
Southern right whales (Eubalaena australis) in South Africa have been extensively studied since 1979 through annual photo-identification surveys. The resulting database revealed an increased rate of reproductive failure in the last decade. As reproductive success is mediated through body condition, this study aimed to assess the body condition and physiological indicators of stress of southern right whales on the South Africa breeding ground at present, and compare it to historical data and other populations. For this, aerial photographs of southern right whales were collected using an unmanned aerial vehicle in September 2019 from which body condition was assessed. Additionally, blubber biopsy samples were collected for glucocorticoid (GC) analysis and compared to the body condition estimates of individual whales. To assess temporal change, analogue aerial photographs taken in coastal South Africa in 1988 and 1989 were selected and digitized for body condition measurements, and compared to the 2019 data set. To determine population differences in body condition, the 2019 data set was compared to body condition data from breeding grounds in Argentina and Australia collected the same year. We found a positive relationship between body condition of lactating southern right whales of the South African population and their blubber GC levels, albeit in a small sample size. The temporal comparison revealed a 24% (SE=5.31) decrease in body condition between 2019 and 1988/1989. Furthermore, lactating females in South Africa were in significantly poorer condition compared to those in Australia and Argentina, at a magnitude of -8.1% (SE=3.07) and -7.1% (SE=3.31), respectively. The reduced maternal body condition in the South African population of southern right whales is of grave concern, as it is likely the main reason behind the reduced reproductive success that is decelerating population recovery. |
format |
Book |
author |
Thavar, Terriann Christiansen, Fredrik Oscar Ganswindt, Andre Sironi, Mariano Uhart, Marcela Bejder, Lars Vermeulen, Els |
spellingShingle |
Thavar, Terriann Christiansen, Fredrik Oscar Ganswindt, Andre Sironi, Mariano Uhart, Marcela Bejder, Lars Vermeulen, Els Southern right whale (Eubalaena australis) body condition and glucocorticoid levels at the South Africa breeding ground |
author_facet |
Thavar, Terriann Christiansen, Fredrik Oscar Ganswindt, Andre Sironi, Mariano Uhart, Marcela Bejder, Lars Vermeulen, Els |
author_sort |
Thavar, Terriann |
title |
Southern right whale (Eubalaena australis) body condition and glucocorticoid levels at the South Africa breeding ground |
title_short |
Southern right whale (Eubalaena australis) body condition and glucocorticoid levels at the South Africa breeding ground |
title_full |
Southern right whale (Eubalaena australis) body condition and glucocorticoid levels at the South Africa breeding ground |
title_fullStr |
Southern right whale (Eubalaena australis) body condition and glucocorticoid levels at the South Africa breeding ground |
title_full_unstemmed |
Southern right whale (Eubalaena australis) body condition and glucocorticoid levels at the South Africa breeding ground |
title_sort |
southern right whale (eubalaena australis) body condition and glucocorticoid levels at the south africa breeding ground |
publisher |
International Whaling Commission |
publishDate |
2021 |
url |
https://pure.au.dk/portal/en/publications/dabf566e-57d1-4b85-be0f-1e57f74c42a6 https://archive.iwc.int/pages/view.php?search=&k=d001be2e01&modal=&display=list&order_by=field74&offset=0&per_page=240&archive=&sort=DESC&restypes=&recentdaylimit=&foredit=&ref=19081 |
genre |
Southern Right Whale |
genre_facet |
Southern Right Whale |
op_source |
Thavar , T , Christiansen , F O , Ganswindt , A , Sironi , M , Uhart , M , Bejder , L & Vermeulen , E 2021 , Southern right whale (Eubalaena australis) body condition and glucocorticoid levels at the South Africa breeding ground . Reports of International Whaling Commission , bind SC/68C/SH/08 , International Whaling Commission . < https://archive.iwc.int/pages/view.php?search=&k=d001be2e01&modal=&display=list&order_by=field74&offset=0&per_page=240&archive=&sort=DESC&restypes=&recentdaylimit=&foredit=&ref=19081 > |
op_relation |
https://pure.au.dk/portal/en/publications/dabf566e-57d1-4b85-be0f-1e57f74c42a6 |
op_rights |
info:eu-repo/semantics/openAccess |
_version_ |
1799467442197495808 |