Post by Nadica (She/Her) on Jul 7, 2024 5:27:45 GMT
University of Queensland research finds whales were less stressed during early COVID pandemic - Published July 4, 2024
In short: Scientists have found Australian humpback whales were less stressed during the first year of the COVID-19 pandemic.
Marine mammalogists believe the reduction in human activity was beneficial to the migratory whales.
What's next?Scientists say humans need to find ways to reduce their impact on these migrating cetaceans.
A new study has found eastern Australian humpback whales were healthier and less stressed during the first year of the COVID-19 pandemic, when human activity on the ocean was limited.
Lead author Jake Linsky and a team of University of Queensland researchers used darts to take skin and blubber samples from whales in the waters off North Stradbroke Island, near Brisbane.
The research, published today, found similar results to a study by Boston scientists from the New England Aquarium shortly after the September 11 terrorist attacks on the World Trade Centre.
Planes and commercial ships ground to a halt after the attacks, and scientists found lower stress hormones in North Atlantic right whale faeces in the following weeks.
Dr Linsky and his team studied the protected Australian whales during their migrations in 2020 and 2021 to track size, health, and energy reserves.
The marine mammalogist said they found significantly lower levels of the stress hormone cortisol in 2021 than 2020 when fewer humans were on the ocean.
Dr Linsky said this could be due to several reasons, such as the large amounts of underwater noise usually generated by commercial ships.
He said whales were highly sensitive to noise, since they used it to navigate and communicate with each other over vast stretches of water.
"Sound is propagating very far and very wide with the commercial vessels in the ocean," Dr Linsky said.
"On the migratory path they're using sound to communicate over great distances, and anything that's going to attenuate their ability to communicate is going to have an impact on the population."
Fewer human impacts
Additionally, Dr Linsky said analysis of gene expression suggested the whales could have been eating fewer polychlorinated biphenyls (PCBs) and other man-made pollutants during the pandemic.
Aside from human activity, he said the whales could also have been impacted by the La Niña conditions, which change the life cycle of Antarctic krill.
The eastern Australian humpback whales were hunted to the brink of extinction in the 1960s and have been the subject of significant conservation efforts.
Dr Linsky said the health of these migratory whales was a good barometer of the health of the Antarctic marine ecosystem as a whole.
He said more research was needed to precisely pin down the various causal mechanisms impacting whale health, but human activity undoubtedly played a large role.
"Our study emphasises the importance of mitigating human impacts so they can continue to thrive in our rapidly changing oceans," Dr Linsky said.
"By continuing to monitor and protect humpback whales off Australia's east coast, we can ensure their health and stability while also offering valuable insights into how other struggling whale populations might be conserved."
The paper was published today in the journal of Marine Environmental Research.
In short: Scientists have found Australian humpback whales were less stressed during the first year of the COVID-19 pandemic.
Marine mammalogists believe the reduction in human activity was beneficial to the migratory whales.
What's next?Scientists say humans need to find ways to reduce their impact on these migrating cetaceans.
A new study has found eastern Australian humpback whales were healthier and less stressed during the first year of the COVID-19 pandemic, when human activity on the ocean was limited.
Lead author Jake Linsky and a team of University of Queensland researchers used darts to take skin and blubber samples from whales in the waters off North Stradbroke Island, near Brisbane.
The research, published today, found similar results to a study by Boston scientists from the New England Aquarium shortly after the September 11 terrorist attacks on the World Trade Centre.
Planes and commercial ships ground to a halt after the attacks, and scientists found lower stress hormones in North Atlantic right whale faeces in the following weeks.
Dr Linsky and his team studied the protected Australian whales during their migrations in 2020 and 2021 to track size, health, and energy reserves.
The marine mammalogist said they found significantly lower levels of the stress hormone cortisol in 2021 than 2020 when fewer humans were on the ocean.
Dr Linsky said this could be due to several reasons, such as the large amounts of underwater noise usually generated by commercial ships.
He said whales were highly sensitive to noise, since they used it to navigate and communicate with each other over vast stretches of water.
"Sound is propagating very far and very wide with the commercial vessels in the ocean," Dr Linsky said.
"On the migratory path they're using sound to communicate over great distances, and anything that's going to attenuate their ability to communicate is going to have an impact on the population."
Fewer human impacts
Additionally, Dr Linsky said analysis of gene expression suggested the whales could have been eating fewer polychlorinated biphenyls (PCBs) and other man-made pollutants during the pandemic.
Aside from human activity, he said the whales could also have been impacted by the La Niña conditions, which change the life cycle of Antarctic krill.
The eastern Australian humpback whales were hunted to the brink of extinction in the 1960s and have been the subject of significant conservation efforts.
Dr Linsky said the health of these migratory whales was a good barometer of the health of the Antarctic marine ecosystem as a whole.
He said more research was needed to precisely pin down the various causal mechanisms impacting whale health, but human activity undoubtedly played a large role.
"Our study emphasises the importance of mitigating human impacts so they can continue to thrive in our rapidly changing oceans," Dr Linsky said.
"By continuing to monitor and protect humpback whales off Australia's east coast, we can ensure their health and stability while also offering valuable insights into how other struggling whale populations might be conserved."
The paper was published today in the journal of Marine Environmental Research.