Acidification: Will It Be a Knockout Blow to Ocean Life?
When it comes to climate change, scientists can’t work in a vacuum, and that’s what makes a new report from the German research network BIOACID (Biological Impacts of Ocean Acidification) so important.
The report, to be presented to policymakers at November’s United Nations climate meeting in Germany, is the culmination of eight years of work and 580 peer-reviewed publications. The project involved lab and field investigations around the world that examined how marine life responds to the ocean’s changing chemistry.
Marine species are often adaptable to acidification to an extent, the report says, but ocean warming, pollution and other threats reduce their resiliency. In one example cited, acidification could slow growth of the planktonic algae Emiliania huxleyi, causing a chain of events that speed up overall atmospheric warming. All kinds of sea life, from corals and crustaceans to large, economically important fish and their prey, are vulnerable as the ocean’s acidity rises – it has already increased 30 percent since the Industrial Revolution, according to the report.
One conclusion reached by the scientists was “how difficult it is to form a clear picture” about how climate change will affect oceans. Major changes aren’t in doubt, but “science is not yet able to assess the exact extent of the risks,” according to the report.
Nations Protect Six Shark Species, Consider Antarctic Marine Reserve
At two international meetings this week, nations have been considering conservation measures for marine life and the Southern Ocean.
The 12th conference of Convention on the Conservation of Migratory Species in the Philippines will conclude on Saturday. In important news for shark conservation, six species will receive protections – including blue sharks, angel sharks and the massive whale shark – that could help depleted populations recover. This follows an unprecedented 21 species of sharks and rays granted protection in 2014. This week, delegates from 120 nations are also considering issues related to marine waste, bycatch, noise and, for the first time, aquatic wild meat.
Meanwhile, for the sixth straight year, the Commission for the Conservation of Antarctic Marine Living Resources, which ended its annual meeting on Friday, failed to reach consensus to create a marine protected area (MPA) in East Antarctica. That came as a “disappointment” to Andrea Kavanagh, Antarctic and Southern Ocean director at the Pew Charitable Trusts, as she and other conservationists would like to create a network of MPAs in the polar region to protect penguins and other vulnerable species. Nations did agree to a long-term monitoring plan for the world’s largest MPA in Antarctica’s Ross Sea, which governments voted to establish in 2016.
Even Oysters Are Stressed Out by Ocean Noise
The constant din and sudden jolts of human-made sound in the ocean are certainly disturbing to marine mammals and fish. Now researchers are learning more about how marine noise pollution affects even invertebrate species that aren’t usually thought of as “hearing.”
Normal behavior for oysters is to close their shells when stressed or threatened. Writing in the journal PLOS ONE about a series of lab experiments, University of Bordeaux researchers reported that oysters quickly closed their shells in response to low-frequency sounds that are typical of cargo boats, oil drilling, wind turbines and seismic research in the sea. They say that the oysters are probably responsive to these frequencies in order to detect currents, waves and tides that are linked to their biological cycles.