On most dives, the day’s adventure begins long before the descent into the sea. As the dive boat heads offshore, seabirds appear almost immediately. Gulls wheel overhead, shearwaters skim effortlessly across the waves, terns plunge after fish, while farther offshore an albatross may be gliding for minutes at a time without a single wingbeat. 

The US Navy has confirmed the identity of a World War II submarine wreck discovered off the coast of Matsuwa Island in the Kuril Islands, bringing closure to a mystery that has endured for more than eight decades.

The wreck has been identified as USS Herring (SS-233), a Gato-class submarine lost on 1 June 1944 during combat operations against Japanese forces in the northern Pacific. All 83 crew members aboard were lost.

Researchers studying killer whales in the North Pacific have uncovered evidence suggesting that orcas may occasionally prey on other orcas, a behaviour rarely documented among the ocean’s top predators.

The clues come from two severed dorsal fins discovered on Bering Island in Russia’s Commander Islands. The fins bore clear tooth marks and other signs of feeding damage, indicating they may have been torn from killer whales and partially consumed.

Eighty-two years after it sank during the pivotal Battle of Midway, USS Yorktown has been revisited in a landmark deep-sea expedition. Using remotely operated vehicles, researchers from NOAA have conducted the first detailed visual survey of the wreck, revealing remarkable preservation and an unexpected find—a 1940s-era vehicle resting on the hangar deck.

The ability of coral reefs to adapt to changing ocean temperatures is a pressing question in marine biology.  

Coral reefs are currently experiencing significant declines. These declines are primarily due to marine heatwaves, which lead to widespread coral bleaching and mortality. Understanding how coral communities can adapt to increasingly severe and frequent marine heatwaves is crucial for their survival in the face of climate change.

(VIDEO: Researcher Al Dove collecting a blood sample. Video by Dr Simon Pierce)

DS: What were some of the challenges encountered when doing underwater ultrasounds? How did the team overcome them?