Oysters Could Cut Ocean Acidification, Wildlife Gains at CITES

One of the many signs of climate change is the movement of animals and plants to new habitats as the earth warms. This has been going on for decades, but was recently documented worldwide for the first time in fish and other marine animals.

They are leaving their original habitats in search of cooler water, according a University of British Columbia study, published in Nature. That is reducing peoples’ access to traditional food sources in developing countries and impacting the fishing industry in advanced nations.

Cod and haddock have moved north, for example, threatening the livelihoods of small fisherman in Massachusetts and Maine. Atlantic surf clams are moving from the Cheseapeake Bay area to New England. 

"Everything depends on some minimal level of predictability, and everything is becoming less and less predictable because of climate change," Glen Spain of the Pacific Coast Federation of Fishermen’s Associations, told the NY Times.

Sea life is moving toward both poles, posing the biggest problems in tropical waters, where they are not being replaced.

Another reason for relocating could be the impact of warmer water on their food. Populations of zooplankton, for example, that feed countless species are down, forcing them to look elsewhere for food. 

Oceans have been absorbing much of the world’s carbon emissions, the cause for its increased acidity. The oceans are 30% more acidic today, which has deleterious effects on marine life from coral reefs to fish larvae and mollusks. Acidification is expected to double by the end of this century.

Emissions from ships also contribute to the problem. Sulfur and nitrous oxide emissions are as problematic as carbon. New rules approved last year will greatly cut those emissions in North America and Europe and the International Maritime Organisation is also enforcing stronger energy efficiency standards for new ships beginning this year.

Like ocean waters around the world, the Chesapeake has become more and more acidic as a result of rising levels of carbon dioxide in the atmosphere. Now, by studying oyster populations in relation to acidity levels, a team of researchers has concluded that oysters – particularly their shells – can play a significant role in reducing that acidity.       

Oysters to the Rescue?

Interestingly, because oyster shells consist of calcium carbonate, healthy populations could help reverse ocean acidification, in the same way an antacid pill helps with heartburn.

"In an undisturbed oyster reef, healthy oysters are generating a lot of biodeposits," a genteel term for excrement, "which helps generate CO₂ to help break down those shells, which helps to regenerate the alkalinity back into the environment," George Waldbusser, a professor at Oregon State and author of a study published in Ecology, told the NY Times. "It creates a positive feedback loop."       

The study recommends adding adult oysters in protected areas to help combat acidification. 

Protection from International Trade 

Unlike in previous years when countries didn’t agree on needed protections for many endangered animals, this year’s CITES meeting was very satisfying.

Elephants, rhinos, sharks, manta rays and turtles – all under extreme pressure from humans – received much needed commitments for protection.

Five species of sharks and two of mantas have been added to the  global list of threatened animals. Once they get on that list,  commercial trade is regulated. Steps will be taken to enforce bans on the trade of ivory and horns from rhinos and elephants and 47 species of turtles and tortoises will receive more protection. 

Led by the US Fish & Wildlife Service, 178 countries participate in CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora). Since 1973, they have been meeting every two or three years to update the list of animals that need more protection from international trade.

"This was a landmark meeting. We had a lot of gains," Ginette Hemley of the World Wildlife Fund, told USA Today. 

CITES voted to require the eight countries where the most ivory and rhino horns are illegally traded (China, Kenya, Malaysia, Philippines, Tanzania, Thailand, Uganda and Vietnam) to boost enforcement or risk sanctions, reports USA Today. 

When there are large seizures of ivory or horns, DNA testing will be required to trace their origins. Delegates also approved measures to curb demand for ivory, such as public-awareness campaigns.

"For the first time in 22 years there was no proposal to sell ivory," exclaimed Iain Douglas-Hamilton, a researcher at the University of Oxford and founder of Save the Elephants, based in Nairobi.

Shark populations are being decimated – about 100 million killed a year just for their fins for shark fin soup. Manta Rays’ gill plates sell as a purifying tonic. Now, fisherman will have to show proof they were legally harvested and get permits to export them.

Trade is banned altogether for some species of turtles and limited for others. They are used medicinally and for pets.

Some tropical hardwoods, including ebonies and rosewoods, also received protection. 

Sadly, the one major vote that didn’t pass would have banned the commercial trade of polar bears. Canada and Greenland voted against a ban, even though Russia was in favor of it. Under extreme pressure from climate change, with their home literally melting underneath them, they are still allowed to be hunted for their skins, claws and teeth.

"At the last CITES conference in Qatar I felt we didn’t get anything we wanted. This conference was entirely different," Leigh Henry of the World Wildlife Fund, told Nature. "The parties to CITES are really stepping up. We got almost everything we wanted. The parties followed the science and did what was best for conservation."

Since its inception, CITES has been instrumental in the recovery of leopards, cheetahs and jaguars and has brought back alligators and crocodiles.