Climate change is posing a severe threat to the habitat of bowhead whales, a threatened Arctic native species. New research has reconstructed an 11,700-year ecological baseline for bowhead whales and projects that sea ice loss will cause their habitat to severely contract by up to 75 per cent by the end of the 21st century.

An international team led by researchers from the University of Adelaide and the University of Copenhagen mapped the location and size of suitable summer foraging habitat for bowhead whales over the entire Holocene. The study used computer models, fossils, and whaling records to find that until recently, this habitat remained constant despite significant climatic fluctuations.

However, the team predicts that future climate change will erode somewhere between 65-75 per cent of this foraging habitat by 2100. In the Sea of Okhotsk, which is home to one of only four populations of bowhead whales, viable summer habitat is likely to vanish entirely by 2060.

The reason for the decline is the collapse of a tight association between bowhead whales and summer sea ice cover. “Bowhead whales have preferred to forage amongst sea ice for many millennia,” said lead author Mr Nicholas Freymueller. However, Arctic sea ice has declined significantly in recent decades, and this is set to accelerate in coming decades.

The study found that the few patches of suitable bowhead habitat predicted to remain in 2100 will exist outside their current distribution, directly impacting conservation policies. “By identifying the extent and location of bowhead whale habitat that is likely to be lost in coming decades, our projections provide vital information to guide future management efforts of this emblematic species,” said Professor Eline Lorenzen.

Bowhead whales are still recovering from four centuries of commercial whaling and are considered emblematic because the ongoing threats they face are reflective of those which all Arctic marine mammal species face due to climate change. The study shows how past perspectives can strengthen predictions of species’ future vulnerability to rapid ocean warming.

This research was published in Ecology and Evolution and provides a critical baseline for conservation efforts aimed at protecting this iconic species from the impacts of climate change.

Uncharted Waters: Surprise Baby Whale Sightings Reveal a More Complex Humpback Migration Pattern

A recent study led by the University of New South Wales (UNSW) has revealed that humpback whales are being born much further south than previously thought, with sightings extending as far as Tasmania – more than 1500 kilometers ahead of the assumed calving zone. This finding challenges current beliefs about where humpback whales give birth and highlights a complex migration pattern that requires increased awareness to protect these marine animals.

Historically, researchers believed that humpback whales migrating north from the nutrient-rich Southern Ocean were traveling to warmer, tropical waters such as the Great Barrier Reef to calve. However, lead author Jane McPhee-Frew, a UNSW PhD candidate and whale watching skipper, discovered that this assumption was incorrect. Her study, which includes over 200 sightings of humpback calves from whale watching operators, citizen scientists, and government wildlife agencies across an area extending from Queensland down to Tasmania and across to New Zealand’s South Island, reveals that these whales are being born in the southernmost parts of their range.

McPhee-Frew notes that once they started investigating, reported sightings came in from further and further south. Eventually, researchers ran out of land to see them from, with reports right to the bottom of Tasmania, the southernmost points of Western Australia, and to the South Island of New Zealand. This emerging pattern suggests humpbacks may have more complex migration and breeding behaviors than previously thought, which comes with a new set of challenges for their protection.

The study also highlights the vulnerability of these young whales as they travel through busy ports and shipping lanes with their long, clumsy fins. Researchers emphasize that people need to be aware that calves are being seen not just on the southern migration but also on the northern one, and that maintaining a safe distance from these animals is crucial for their protection.

McPhee-Frew stresses that partnering with government agencies and sharing information ultimately supports better policies to protect whales. She also emphasizes the importance of whale watching operators in providing sightings data as well as educating the public about safe approaches. Social media platforms like Instagram and Facebook are invaluable tools for citizen science, for sharing images and information about whale sightings.

The study raises an unanswered question: Why do humpback mothers continue to use the ‘humpback highway’ to travel north after giving birth? McPhee-Frew suggests that rather than holding a strict view of migratory patterns with fixed endpoints, the focus is shifting to how humpbacks use different marine environments on their journey. Researchers still have much to learn about these complex behaviors and emphasize that it’s such a privilege to see whales – we just need to follow the rules so everyone can enjoy them.

The Galapagos Islands, a natural living laboratory due to their unique and endemic species, are home to a variety of birds, including the Galapagos yellow warbler (Setophaga petechia aureola). A new study has discovered that these birds are changing their behavior in response to traffic noise, with those frequently exposed to vehicles showing heightened levels of aggression.

Researchers from Anglia Ruskin University and the Konrad Lorenz Research Centre at the University of Vienna conducted a study on the impact of vehicle noise pollution on Galapagos yellow warblers. They found that birds living in roadside territories showed increased aggression when confronted with traffic noise, while those living away from roads showed decreased aggression.

The researchers also observed that Galapagos yellow warblers on the more populous island of Santa Cruz increased the duration of their song when confronted by traffic noise. This suggests that long-term selection based on noise experience allows them to adapt and adjust the features of their songs.

Importantly, the effect of living on a roadside territory was present even on Floreana Island, with only about 10 vehicles present on the island. This suggests that even minimal exposure to traffic affects responses to noise.

The study’s findings support the idea that birds use song during territorial defense as an aggressive signal. However, if external noise such as traffic interferes with this signaling, increasing physical aggression would be an appropriate response.

Co-author Dr Caglar Akcay said: “Our results show that the change in aggressive responses in yellow warblers occurred mainly near roads. Birds occupying roadside territories on both islands, and therefore having regular experience of traffic noise, may have learned to increase physical aggression when the territorial intrusion was accompanied by traffic noise.”

The study highlights the importance of considering behavioral plasticity in conservation efforts and developing strategies to mitigate the effects of noise pollution on wildlife.

In conclusion, the Galapagos yellow warbler’s aggressive behavior due to traffic noise is a concerning issue that requires attention from policymakers and conservationists. The study’s findings emphasize the need for more research on the impact of noise pollution on wildlife and the development of effective strategies to minimize its effects.