A whale tail off the east coast of Australia. Credit: Jake Linsky.
Research led by the University of Queensland has found that migrating whales off Australia’s east coast became less stressed during the first year of the COVID-19 pandemic. The research paper was published in Marine Environmental Research.
Dr. Jake Linsky from UQ’s School of the Environment led a study from Moreton Bay Research Station to measure the health of species during a time of unprecedented change in human activity.
“We used drone photography and sediment samples to assess the health of eastern Australian humpback whales in the waters off Minjerribah—North Stradbroke Island—during their migration in 2020 and 2021,” said Dr. Linsky.
“This population has made one of the most successful recoveries from historic whaling, so we wanted to use the latest tools at our disposal to check their health.”
The researchers used drone imagery to measure the whale’s size and body condition.
“These are essential indicators of the energy reserves used during their long annual migration and intensive breeding season,” said Dr. Linsky.
“We also used small boats to approach the whales and collect small samples of skin and blubber from the whales’ flanks.
“These lacquer samples were analyzed for hormones and gene expressions related to stress, energy stores and immune health.”
Laboratory results revealed significantly lower cortisol concentrations in whales in 2021 compared to 2020.
“This change in their physiology suggests a decrease in environmental stressors between the two years,” said Dr. Linsky.
“Several things happened during this period that likely contributed to our findings, including a La Niña climate change and dramatic changes in human activity during the pandemic.
“Our gene expression results also raise a further hypothesis that the whales may have responded to a decline in pollutants in their distant feeding waters.
“Previous studies have found similar changes in stress hormones in whales on the opposite side of the Antarctic continent – our findings support the idea that these changes occurred throughout the Southern Ocean.”
The researchers said the results highlight the role of migrating whales as indicators of the health of Antarctic marine ecosystems.
“Eastern Australian humpback whales have demonstrated a remarkable ability to adapt to changes in their environment, but our study highlights the importance of mitigating human impacts so they can continue to thrive in our rapidly changing oceans ,” said Dr. Linsky.
“By continuing to monitor and protect humpback whales off Australia’s east coast, we can ensure their health and stability while also providing valuable insights into how other whale populations in distress can be conserved.”
More information:
Jacob MJ Linsky et al, Blubber gene expression and cortisol concentrations reveal changing physiological stress in a southern ocean sentinel species, Marine Environmental Research (2024). DOI: 10.1016/j.marenvres.2024.106596
Provided by the University of Queensland
citation: Research finds humpbacks were happier during pandemic hiatus (2024, July 5) Retrieved July 6, 2024 from https://phys.org/news/2024-07-humpbacks-happier-pandemic.html
This document is subject to copyright. Except for any fair agreement for study or private research purposes, no part may be reproduced without written permission. The content is provided for informational purposes only.