Seasonal productivity drives aggregations of killer whales and other cetaceans over submarine canyons of the Bremer Sub-Basin, south-western Australia
Cetaceans are iconic predators that serve as important indicators of marine ecosystem health. The Bremer Sub-Basin, south-western Australia, supports a diverse cetacean community including the largest documented aggregation of killer whales (Orcinus orca) in Australian waters. Knowledge of cetacea...
| Main Authors: | , , , , , |
|---|---|
| Format: | Journal Article |
| Language: | English |
| Published: |
CSIRO PUBLISHING
2020
|
| Subjects: | |
| Online Access: | http://hdl.handle.net/20.500.11937/80261 |
| _version_ | 1848764191910920192 |
|---|---|
| author | Salgado Kent, Chandra Bouchet, Phil Wellard, Rebecca Parnum, Iain Fouda, Leila Erbe, Christine |
| author_facet | Salgado Kent, Chandra Bouchet, Phil Wellard, Rebecca Parnum, Iain Fouda, Leila Erbe, Christine |
| author_sort | Salgado Kent, Chandra |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Cetaceans are iconic predators that serve as important indicators of marine ecosystem health. The Bremer
Sub-Basin, south-western Australia, supports a diverse cetacean community including the largest documented aggregation
of killer whales (Orcinus orca) in Australian waters. Knowledge of cetacean distributions is critical for managing the
area’s thriving ecotourism industry, yet is largely sporadic. Here we combined aerial with opportunistic ship-borne surveys
during 2015–2017 to describe the occurrence of multiple cetacean species on a regional scale. We used generalised
estimating equations to model variation in killer whale relative density as a function of both static and dynamic covariates,
including seabed depth, slope, and chlorophyll a concentration, while accounting for autocorrelation. Encountered
cetacean groups included: killer (n ¼ 177), sperm (n ¼ 69), long-finned pilot (n ¼ 29), false killer (n ¼ 2), and straptoothed beaked (n ¼ 1) whales, as well as bottlenose (n ¼ 12) and common (n ¼ 5) dolphins. Killer whale numbers peaked
in areas of low temperatures and high primary productivity, likely due to seasonal upwelling of nutrient-rich waters
supporting high prey biomass. The best predictive model highlighted potential killer whale ‘hotspots’ in the Henry, Hood,
Pallinup and Bremer Canyons. This study demonstrates the value of abundance data from platforms of opportunity for
marine planning and wildlife management in the open ocean. |
| first_indexed | 2025-11-14T11:15:26Z |
| format | Journal Article |
| id | curtin-20.500.11937-80261 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-14T11:15:26Z |
| publishDate | 2020 |
| publisher | CSIRO PUBLISHING |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-802612021-01-14T04:15:22Z Seasonal productivity drives aggregations of killer whales and other cetaceans over submarine canyons of the Bremer Sub-Basin, south-western Australia Salgado Kent, Chandra Bouchet, Phil Wellard, Rebecca Parnum, Iain Fouda, Leila Erbe, Christine Science & Technology Life Sciences & Biomedicine Zoology generalised estimating equations habitat modelling submarine canyons temporal autocorrelation whale watching ESTIMATING EQUATIONS FORAGING BEHAVIOR HABITAT MODELS POPULATION ABUNDANCE PREFERENCES SELECTION POD BAY Cetaceans are iconic predators that serve as important indicators of marine ecosystem health. The Bremer Sub-Basin, south-western Australia, supports a diverse cetacean community including the largest documented aggregation of killer whales (Orcinus orca) in Australian waters. Knowledge of cetacean distributions is critical for managing the area’s thriving ecotourism industry, yet is largely sporadic. Here we combined aerial with opportunistic ship-borne surveys during 2015–2017 to describe the occurrence of multiple cetacean species on a regional scale. We used generalised estimating equations to model variation in killer whale relative density as a function of both static and dynamic covariates, including seabed depth, slope, and chlorophyll a concentration, while accounting for autocorrelation. Encountered cetacean groups included: killer (n ¼ 177), sperm (n ¼ 69), long-finned pilot (n ¼ 29), false killer (n ¼ 2), and straptoothed beaked (n ¼ 1) whales, as well as bottlenose (n ¼ 12) and common (n ¼ 5) dolphins. Killer whale numbers peaked in areas of low temperatures and high primary productivity, likely due to seasonal upwelling of nutrient-rich waters supporting high prey biomass. The best predictive model highlighted potential killer whale ‘hotspots’ in the Henry, Hood, Pallinup and Bremer Canyons. This study demonstrates the value of abundance data from platforms of opportunity for marine planning and wildlife management in the open ocean. 2020 Journal Article http://hdl.handle.net/20.500.11937/80261 10.1071/AM19058 English http://creativecommons.org/licenses/by/4.0/ CSIRO PUBLISHING fulltext |
| spellingShingle | Science & Technology Life Sciences & Biomedicine Zoology generalised estimating equations habitat modelling submarine canyons temporal autocorrelation whale watching ESTIMATING EQUATIONS FORAGING BEHAVIOR HABITAT MODELS POPULATION ABUNDANCE PREFERENCES SELECTION POD BAY Salgado Kent, Chandra Bouchet, Phil Wellard, Rebecca Parnum, Iain Fouda, Leila Erbe, Christine Seasonal productivity drives aggregations of killer whales and other cetaceans over submarine canyons of the Bremer Sub-Basin, south-western Australia |
| title | Seasonal productivity drives aggregations of killer whales and other cetaceans over submarine canyons of the Bremer Sub-Basin, south-western Australia |
| title_full | Seasonal productivity drives aggregations of killer whales and other cetaceans over submarine canyons of the Bremer Sub-Basin, south-western Australia |
| title_fullStr | Seasonal productivity drives aggregations of killer whales and other cetaceans over submarine canyons of the Bremer Sub-Basin, south-western Australia |
| title_full_unstemmed | Seasonal productivity drives aggregations of killer whales and other cetaceans over submarine canyons of the Bremer Sub-Basin, south-western Australia |
| title_short | Seasonal productivity drives aggregations of killer whales and other cetaceans over submarine canyons of the Bremer Sub-Basin, south-western Australia |
| title_sort | seasonal productivity drives aggregations of killer whales and other cetaceans over submarine canyons of the bremer sub-basin, south-western australia |
| topic | Science & Technology Life Sciences & Biomedicine Zoology generalised estimating equations habitat modelling submarine canyons temporal autocorrelation whale watching ESTIMATING EQUATIONS FORAGING BEHAVIOR HABITAT MODELS POPULATION ABUNDANCE PREFERENCES SELECTION POD BAY |
| url | http://hdl.handle.net/20.500.11937/80261 |