Exploring a Long-Hidden Ocean World Exposed by Iceberg Calving
When a massive chunk of ice the size of Delaware and known as A-68 calved from the Larsen Ice Sheet in Antarctica last July, it left exposed a marine ecosystem on the seafloor that had been covered by ice for up to 120,000 years.
An international team of scientists from nine research institutions headed there this month to explore and collect animal, plant, microbe and water samples, before new species have much of a chance to move in and colonize the area.
“The calving of A-68 provides us with a unique opportunity [to] study marine life as it responds to a dramatic environmental change,” mission leader Katrin Linse from the British Antarctic Survey said in a statement.
In 2017, an international governing body, the Commission for the Conservation of Antarctic Marine Living Resources, designated the location as an Area for Special Scientific Study for a period of 10 years – prohibiting commercial fishing and other activities. It is the first study area declared under a 2016 agreement to create scientific protected zones following the collapse or retreat of ice shelves in the region.
Blue Whale Songs Give Clues to Behavior
Endangered blue whales, the largest animal on Earth, have had researchers spying on their chatter in an effort to understand the elusive meaning of their songs.
In a long-term study from 2002 to 2016, scientists tagged whales in the waters of Southern California and then used underwater microphones to tape and analyze more than 4,500 blue whale sounds. Oceanographer Ana Sirovic from the Scripps Institution of Oceanography presented her team’s results at a scientific meeting in Oregon on Feb. 13.
The scientists identified and compared three calling behaviors that were linked to various diving patterns and the whale’s sex. Males were louder at night and produced more calls and songs than females, indicating some sounds may be part of a mating ritual. Fascinatingly, singing males also dove deeper. The researchers found calls may serve a variety of other purposes, such as signaling the presence of prey or maintaining distance among individuals as their massive bodies move through the water. Understanding the context of the calls, Sirovic said in a statement, could help scientists develop better methods to study and conserve blue whale populations.
Arctic Ringed Seals Win U.S. Protection
A federal appeals court in the United States ruled this week that Arctic ringed seals should receive Endangered Species Act protections as their sea-ice habitat melts.
The decision for now ends a protracted legal battle fought between conservation groups and the oil industry and the Alaska state government over the designation of both ringed seals and bearded seals, first proposed in 2012. In 2016, a judged ruled that bearded seal protection would also stand.
Even though their current populations are relatively healthy, ringed seals depend on sea ice for rearing their young. The ice’s disappearance or early breakup in the season increasingly exposes pups to predators and frigid waters, the listing said. In 2016, a lower court had ruled the listing as “speculative,” according to the Center for Biological Diversity, but the appeals court reversed that decision this month.
The next step under the federal Endangered Species Act is another involved process of designating critical habitat that is crucial to the seals’ survival, which could be used to limit oil and gas development in those areas. However, the legal battle may not be over. According to InsideClimate News, state and industry groups are still considering strategies for blocking the listings.