Whales

Blue whale off Sri Lanka
Between 2011 and 2020, 41 different blue whales have been photo-identified from South Georgia, none of which match the 517 whales in the current Antarctic blue whale photographic catalogue.

Blue whale numbers rebound off South Georgia

When whaling all but exterminated the Antarctic blue whale 50 years ago, the waters around South Georgia fell silent. Between 1998 and 2018, dedicated whale surveys off the sub-Antarctic island yielded a sole blue whale sighting. But a whale expedition this year and analysis by an international research team resulted in 58 blue whale sightings and numerous acoustic detections, raising hopes that the critically endangered mammal is finally recovering five decades after whaling was banned.

Humpback whale breaching

Humpback whale numbers soar off Australia

After hitting a low of 300 individuals 30 years, humpback whale numbers off Australia’s east coast are soaring. Researchers from Australia’s Organization for the Rescue and Research of Cetaceans (ORRCA) are hoping for an increase in whale migration numbers this year. Census results from the past 21 years indicate an annual 10-15 per cent increase in whale migration numbers.

Humpback whales revel in Alaska's cruise-free summer

It’s been a quiet summer in the waters of Alaska.

With zero cruise ships carrying whale-watchers and glacier gazers—a situation which temporarily boosts the state’s population of 730,000 by 1.4m individuals—the humpback whales in the vicinity have grown much more talkative.

This is the impression that delighted researchers are getting.

UNSW researcher Dr Catharina Vendl holding the telescopic pole she used to collect samples of whales' blow in Hervey Bay, Queensland, in 2017.

Migrating humpback whales have poor health on return journey

Every summer, East Australian humpback whales migrate from the feeding grounds in Antarctica to their breeding grounds in the Great Barrier Reef. They remain there for about several months, before making their way around the southern Australian coast back to Antarctica for the winter.

Swimming with dolphins
Swimming with and learning from dolphins

Learning the swimming secrets of dolphins and whales

This scenario may one day become reality. And to be efficient, such robots would need to be maneuverable and stealthy, and be able to closely mimic the movements of the marine creatures.

Scientists like Keith W. Moored are working on the next generation of underwater robots by studying the movements of dolphins and whales. "We're studying how these animals are designed and what's beneficial about that design in terms of their swimming performance, or the fluid mechanics of how they swim."

Sperm whales off Dominica. The sperm whale (Physeter macrocephalus) or cachalot is the largest of the toothed whales

2016 New Zealand quake disrupted sperm whales' foraging behaviour

In November 2016, a 7.8 magnitude earthquake in New Zealand triggered underwater mudslides in the underwater canyon off the coastline. This led to high-velocity currents to flush 850 tonnes of sediment from the canyon into the ocean.

This "canyon flushing" caused what was once a diverse ecosystem of invertebrates along the Kaikoura underwater canyon to become as "quiet as a desert."

A paper in the Deep Sea Research Part I journal describes how sperm whales were subsequently affected by the quake and how they changed their foraging habits as a result.

Gray whale spyhopping off the Alaskan coast
Gray whale spyhopping off the Alaskan coast

Solar storms can mess with a whale's GPS

After studying 186 live strandings of healthy gray whales from 1985 to 2018, researchers at Duke University concluded that whales' navigational sense is affected by solar storms taking place as far away as our sun.

The researchers based their findings on the fact that the strandings are more likely to occur on days when there are more sunspots. Linked to solar storms, sunspots represent sudden releases of high-energy particles from the sun. These may disrupt magnetic orientation behaviour when they interact with the Earth’s magnetosphere.

Record numbers of marine mammals, like bottlenose dolphins, have been recorded in the United Kingdom.

UK sees record sightings of whales, dolphins and seals

The Wildlife Trusts, which comprises 46 individual wildlife trusts around the country, reports record numbers of more than 800 sightings of whales, dolphins and seals in the waters of the United Kingdom in 2019.

Its Yorkshire project reported hundreds of individual sightings by trained citizen scientists. Among these were a pod of bottlenose dolphins making their way from Scotland to Flamborough Head in East Yorkshire-the farthest south they had been officially identified.