Orcas are justly famed for their ability to work together as a group to kill dinner. Now, pods of orcas have been observed hunting and killing the world’s largest animal, the blue whale.

A recently published paper in Marine Mammal Science shone a light on three attacks since 2019 recorded off the coast of Australia. The hunts, which were observed from commercial whale-watching vessels, taught researchers much about how the orca work together — and also revealed a surprising display of orca “girl power” in all its gruesome detail.

Observers were surprised to note that all three attacks were led by female orcas, rather than the larger male orcas. In two of the cases, they were also intrigued to see a female take the lead in grabbing a protein-rich piece of the doomed blue whale as it began to sink. “While it was still alive,” the paper explained, “an adult female killer whale put its head inside the blue whale’s mouth and began feeding on its tongue.”

Previously, it had been assumed that for killer whale attacks on large whales to be successful, adult males need to be involved. Females are about 20 per cent smaller. 

What’s for dinner?

It’s a whole lot more pleasant than sorting through caribou poop. A newly published study in Ecology and Evolution saw scientists researching caribou diets by equipping 30 female caribou from the Fortymile Herd with their own GPS-activated cameras — essentially a GoPro for caribou.

The cameras were attached in 2018 and 2019 to females in the Fortymile Herd, which ranges across eastern Alaska and into Yukon. They were designed to fall off in the summer of 2021, sending location signals that allowed researchers to retrieve them.

Turns out, caribou do a whole lot of eating (43.5 per cent of their time, to be exact). This was no surprise. What intrigued scientists was exactly what they ate — and when. In winter, they ate mainly lichen, but in summer they switched over to shrubs, a more nutritious and protein-filled repast. This was good news in that shrubs are spreading northward with climate change.

But the cameras also shone a spotlight on how a warming climate is making life easier for one of the caribou’s most annoying harassers — insects. The cameras showed clouds of insects affecting the caribou by July, forcing the animals to spend less time feeding and more time moving as they tried to outrun the insects. 

Animal-borne video cameras provide an exciting opportunity to study what large herbivores are eating (as well as their behaviour and weather conditions) — especially in remote regions. 

Flyway patrol

A new citizen-science project is charting ‘avian highways’ and other important habitats in Nova Scotia. Armed with audio recorders and artificial intelligence technology, the Listening Together project will record and analyze bird calls — particularly those of the Canada warbler and the Leach’s storm petrel, two at-risk species. While habit protection efforts often focus on breeding grounds, this project will look at identifying and protecting the habitats along migratory routes where birds like the warbler spend half their year. In the case of the Leach’s storm petrel, the focus will be on identifying nesting sites on remote islands.

The recorders are the size of a bar of soap and can be placed in a water-proof plastic bag. They are hung on a tree or post, where they record the sound of passing birds. AI software takes care of the rest, using machine learning to pick out the relevant bird calls. The audio recorders being used are simple, sturdy and inexpensive — with the dual benefit of providing more data and allowing citizens to participate directly in data collection. Two birds, one stone!

Astro-nuts