Range-Wide Comparison of Gray Whale Body Condition Reveals Contrasting Sub-Population Health Characteristics and Vulnerability to Environmental Change
Climate change is a global phenomenon, yet impacts on resource availability to predators may be spatially and temporally diverse and asynchronous. As capital breeders, whales are dependent on dense, predictable prey resources during foraging seasons. An Unusual Mortality Event (UME) of Eastern North...
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Online Access: | http://dx.doi.org/10.3389/fmars.2022.867258 https://www.frontiersin.org/articles/10.3389/fmars.2022.867258/full |
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crfrontiers:10.3389/fmars.2022.867258 2024-06-23T07:49:41+00:00 Range-Wide Comparison of Gray Whale Body Condition Reveals Contrasting Sub-Population Health Characteristics and Vulnerability to Environmental Change Torres, Leigh G. Bird, Clara N. Rodríguez-González, Fabian Christiansen, Fredrik Bejder, Lars Lemos, Leila Urban R, Jorge Swartz, Steven Willoughby, Amy Hewitt, Joshua Bierlich, KC. 2022 http://dx.doi.org/10.3389/fmars.2022.867258 https://www.frontiersin.org/articles/10.3389/fmars.2022.867258/full unknown Frontiers Media SA https://creativecommons.org/licenses/by/4.0/ Frontiers in Marine Science volume 9 ISSN 2296-7745 journal-article 2022 crfrontiers https://doi.org/10.3389/fmars.2022.867258 2024-06-11T04:09:18Z Climate change is a global phenomenon, yet impacts on resource availability to predators may be spatially and temporally diverse and asynchronous. As capital breeders, whales are dependent on dense, predictable prey resources during foraging seasons. An Unusual Mortality Event (UME) of Eastern North Pacific (ENP) gray whales ( Eschrichtius robustus ) was declared in 2019 due to a dramatic rise in stranded animals, many emaciated. Climate change impacts may have affected prey availability on the primary foraging grounds of ENP gray whales (~20,000 individuals) in the Arctic and sub-Arctic region and in coastal habitats between northern California, USA and British Columbia, Canada where a small sub-group of ENP whales called the Pacific Coast Feeding Group (PCFG; ~230 individuals) forages. To investigate variability of gray whale body condition relative to changing ocean conditions, we compare two datasets of gray whale aerial photogrammetry images collected via Unoccupied Aircraft Systems (UAS) on the ENP wintering grounds in San Ignacio Lagoon, Mexico (SIL; n=111) and on the PCFG feeding grounds in Oregon, USA (n=72) over the same three-year period (2017–2019). We document concurrent body condition improvement of PCFG whales in Oregon while body condition of whales in SIL declined. This result indicates that the UME may have affected ENP whales due to reduced energetic gain on some Arctic/sub-Arctic foraging grounds, while PCFG whales are recovering from poor prey conditions during the NE Pacific marine heatwave event of 2014–2016. Surprisingly, we found that PCFG whales in Oregon had significantly worse body condition than whales in SIL, even when accounting for year and phenology. We derive support for this unexpected finding via photogrammetry analysis of opportunistic aerial images of gray whales on Arctic foraging grounds (n=18) compared to PCFG whales in Oregon (n=30): the body condition of PCFG whales was significantly lower (t=2.96, p=0.005), which may cause PCFG whales to have reduced reproductive ... Article in Journal/Newspaper Arctic Climate change Frontiers (Publisher) Arctic British Columbia ENVELOPE(-125.003,-125.003,54.000,54.000) Canada Pacific Frontiers in Marine Science 9 |
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Open Polar |
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Frontiers (Publisher) |
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crfrontiers |
language |
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description |
Climate change is a global phenomenon, yet impacts on resource availability to predators may be spatially and temporally diverse and asynchronous. As capital breeders, whales are dependent on dense, predictable prey resources during foraging seasons. An Unusual Mortality Event (UME) of Eastern North Pacific (ENP) gray whales ( Eschrichtius robustus ) was declared in 2019 due to a dramatic rise in stranded animals, many emaciated. Climate change impacts may have affected prey availability on the primary foraging grounds of ENP gray whales (~20,000 individuals) in the Arctic and sub-Arctic region and in coastal habitats between northern California, USA and British Columbia, Canada where a small sub-group of ENP whales called the Pacific Coast Feeding Group (PCFG; ~230 individuals) forages. To investigate variability of gray whale body condition relative to changing ocean conditions, we compare two datasets of gray whale aerial photogrammetry images collected via Unoccupied Aircraft Systems (UAS) on the ENP wintering grounds in San Ignacio Lagoon, Mexico (SIL; n=111) and on the PCFG feeding grounds in Oregon, USA (n=72) over the same three-year period (2017–2019). We document concurrent body condition improvement of PCFG whales in Oregon while body condition of whales in SIL declined. This result indicates that the UME may have affected ENP whales due to reduced energetic gain on some Arctic/sub-Arctic foraging grounds, while PCFG whales are recovering from poor prey conditions during the NE Pacific marine heatwave event of 2014–2016. Surprisingly, we found that PCFG whales in Oregon had significantly worse body condition than whales in SIL, even when accounting for year and phenology. We derive support for this unexpected finding via photogrammetry analysis of opportunistic aerial images of gray whales on Arctic foraging grounds (n=18) compared to PCFG whales in Oregon (n=30): the body condition of PCFG whales was significantly lower (t=2.96, p=0.005), which may cause PCFG whales to have reduced reproductive ... |
format |
Article in Journal/Newspaper |
author |
Torres, Leigh G. Bird, Clara N. Rodríguez-González, Fabian Christiansen, Fredrik Bejder, Lars Lemos, Leila Urban R, Jorge Swartz, Steven Willoughby, Amy Hewitt, Joshua Bierlich, KC. |
spellingShingle |
Torres, Leigh G. Bird, Clara N. Rodríguez-González, Fabian Christiansen, Fredrik Bejder, Lars Lemos, Leila Urban R, Jorge Swartz, Steven Willoughby, Amy Hewitt, Joshua Bierlich, KC. Range-Wide Comparison of Gray Whale Body Condition Reveals Contrasting Sub-Population Health Characteristics and Vulnerability to Environmental Change |
author_facet |
Torres, Leigh G. Bird, Clara N. Rodríguez-González, Fabian Christiansen, Fredrik Bejder, Lars Lemos, Leila Urban R, Jorge Swartz, Steven Willoughby, Amy Hewitt, Joshua Bierlich, KC. |
author_sort |
Torres, Leigh G. |
title |
Range-Wide Comparison of Gray Whale Body Condition Reveals Contrasting Sub-Population Health Characteristics and Vulnerability to Environmental Change |
title_short |
Range-Wide Comparison of Gray Whale Body Condition Reveals Contrasting Sub-Population Health Characteristics and Vulnerability to Environmental Change |
title_full |
Range-Wide Comparison of Gray Whale Body Condition Reveals Contrasting Sub-Population Health Characteristics and Vulnerability to Environmental Change |
title_fullStr |
Range-Wide Comparison of Gray Whale Body Condition Reveals Contrasting Sub-Population Health Characteristics and Vulnerability to Environmental Change |
title_full_unstemmed |
Range-Wide Comparison of Gray Whale Body Condition Reveals Contrasting Sub-Population Health Characteristics and Vulnerability to Environmental Change |
title_sort |
range-wide comparison of gray whale body condition reveals contrasting sub-population health characteristics and vulnerability to environmental change |
publisher |
Frontiers Media SA |
publishDate |
2022 |
url |
http://dx.doi.org/10.3389/fmars.2022.867258 https://www.frontiersin.org/articles/10.3389/fmars.2022.867258/full |
long_lat |
ENVELOPE(-125.003,-125.003,54.000,54.000) |
geographic |
Arctic British Columbia Canada Pacific |
geographic_facet |
Arctic British Columbia Canada Pacific |
genre |
Arctic Climate change |
genre_facet |
Arctic Climate change |
op_source |
Frontiers in Marine Science volume 9 ISSN 2296-7745 |
op_rights |
https://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.3389/fmars.2022.867258 |
container_title |
Frontiers in Marine Science |
container_volume |
9 |
_version_ |
1802640271465250816 |