Whales

With an estimated weight of 412.3 pounds (187 kilograms) and a length of 8.2 feet (2.5 meters), this newly documented species is roughly the size of a modern-day bottlenose dolphin.

Named Tutcetus rayanensis, this creature belonged to the extinct basilosauridae family, which was one of the earliest groups to become fully aquatic. As revealed in a study published in Communications Biology on Thursday, this diminutive specimen is considerably older than other basilosaurids from the Eocene Epoch.

In a world where facial recognition technology is becoming commonplace, it is not just humans who are being identified. A groundbreaking study has successfully applied this technology to identify individual whales and dolphins in the wild across 24 species.

“I have taken the decision to suspend whaling” until 31 August, food minister Svandis Svavarsdottir said in a statement, after a recent government-commissioned report concluded the hunt does not comply with Iceland’s Animal Welfare Act.

The report which provided a video showing a whale being hunted for five hours concluded the killing of whales during the hunt took too long.

Animal rights groups and environmentalists hailed the decision, with the Humane Society International calling it “a major milestone in compassionate whale conservation”.

Ship strikes are a major threat to whales globally and to the recovery of endangered blue, fin, and humpback whales in California waters. From 2007-2022, observed and documented deaths totalled 52 endangered whales, likely representing a small fraction of the annual total number of ship strikes.

Drone footage of marine mammals helps us better understand their behaviour and social structure or simply provides us with some stunning footage we couldn't obtain otherwise. However, drones can also affect whales, dolphins and other mammals if flown too close.

So what is too close and what are safe distances?

Last summer, the highly contagious strain of avian influenza, that was first detected in early winter 2021, had been spreading through North American birds made its way into marine mammals, causing a spike in seal strandings along the coast of Maine.

In June and July 2022, more than 150 dead or ailing seals washed ashore, a number that was approximately three times the normal rate for this time of the year. Of the 41 stranded seals tested for the virus, nearly half tested positive.

Cancer should be a near certainty for whales, being the longest-living and largest mammals there are. Across species, the higher the number of cells, the greater the number of cell divisions and the higher the probability of DNA damage and the transformation of a normal cell into a cancerous one.

However, the occurrence of cancer does not show a correlation with body mass. The lack of correlation between body mass and cancer risk is known as Peto’s paradox.

A study of 22 toothed whales which died in strandings along the Scottish coast shows that some of them exhibited hallmarks of Alzheimer’s disease, and this might have—at least in part—caused the stranding incident.

The dolphin species involved in the study were five species: Risso’s dolphins, long-finned pilot whales, white-beaked dolphins, harbour porpoises and bottlenose dolphins.

From March to July, phytoplankton blooms emerge along Calfornia’s Central Coast, as seasonal winds push the top layer of the waters out to sea, thereby allowing the cooler, nutrient-rich waters to rise to the surface.

Many marine animals are drawn to such oceanic upwellings, which consequently turn into their feeding grounds. For instance, krill gather to feed on the abundant phytoplankton, whilst blue whales converge to feed on the krill.

Once the upwelling ceases, these marine creatures move elsewhere.

After studying more than 23,000 sperm whale vocalisations recorded from 1978 to 2017 in the Pacific Ocean, researchers have concluded that sperm whales use distinctive vocalisations to identify themselves with specific whale clans.

Called “identity codas,” these vocalisations comprise sequences of clicking sounds that distinguish different social groups. They are different from non-identity vocalisations used across all the different whale clans.