Researchers from Canada and Norway are reporting a surprising uptick in the level of cross-breeding between the blue whale and fin whale, two of the world’s largest species. Talk about a heavy baby!

Published in Conservation Genetics last month, the researchers found that 3.5 per cent of blue whale DNA was made up of fin whale DNA after collecting tissue samples from 28 North Atlantic blue whales. “This is remarkable as they are not sibling species and diverged about 8.35 million years ago,” the study reads. 

Hybrids between species are often infertile, but a 2018 study found that gene flow was at one point able to occur between the blue and fin whale, with a female hybrid having carried a fetus after mating with a blue whale.. Other studies have suggested the two species might not be far enough apart on the evolutionary tree to be completely incompatible.

While interesting, the finding draws concerns from researchers, who worry that disproportionate gene flow from the far more abundant fin whale could present a threat to NA blue whale populations due to loss of genetic integrity.

For the birds

Environmental groups and a federal court judge have urged Canada’s environment minister to reevaluate his stance on the protection of endangered migratory birds, such as the marbled murrelet, saying he has interpreted a federal ruling too narrowly. The ruling required the federal government to better ensure the survival and recovery of the at-risk birds.

Chief Justice Paul Crampton heeded the call from two environmental groups that alleged minister Steven Guilbeault had taken no obligation to protect anything other than nests on provincial lands. Crampton found the minister’s 2022 interpretation of the ruling to be unreasonably narrow, as Guilbeault had argued that his interpretation maximized the provincial ability to act in an area of shared jurisdiction.

At the heart of the environmentalists’ outcry was the small endangered bird known as the marbled murrelet. Threats to these birds, along with 25 other ar risk migratory birds, include industrial logging and climate change-fuelled wildfires along British Columbia’s forests. The two environmentalist groups — represented by a lawyer from environmental law charity Ecojustice — argued that the government had already failed to protect these threatened species from harm, leaving the nesting habitat less than suitable for survival and recovery.

Minister Guilbeault will be returning his protection statement to the government for further consideration.

Jellyfish buffet

Climate change is driving jellyfish populations to migrate northward in large numbers into Arctic waters — but this might not be the trophic dead-end ecologists once thought. 

According to research published in Frontiers in Marine Science, species of Arctic zooplankton are shifting from an omnivorous diet to profit off this surprising new source of nutrients, putting to bed the theory that jellyfish were too devoid of nutrients for the amphipods. It’s a shift that comes as a result of food scarcity during long, dark polar winters.

“We found evidence that some amphipods feast on ‘jelly-falls,’ naturally sunken jellyfish carcasses. Other species may also prey on living jellyfish,” says Annkathrin Dischereit, a doctoral student at the Alfred Wegener Institute. Dischereit was one of a handful of investigators who travelled to the AWIPEV research station on Svalbard, Norway. Dissecting the guts from local amphipods, the researchers were able to identify jellyfish DNA in all four species of amphipods captured. The A. sarsi and O. minuta were found to be preying on opportunistic ‘jelly-falls,’ while the more adventurous Gammarus appeared to be consuming live comb jellies in addition.

With jellyfish taking a newfound role in the Arctic food chain, Dischereit concluded that there will have to be renewed effort in evaluating the ecosystem being called the ‘new Arctic.’

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