Warming seas threatening coral

A striking rise in sea temperatures in waters off Indonesia may be responsible for one of the most rapid and destructive coral bleaching events on record, a marine conservation group reported recently. Large swaths of coral reef in the Andaman Sea off the north coast of Sumatra are now up to 80 per cent bleached, with more colonies expected to die off in the coming months, according to marine biologists who conducted extensive surveys of the area. The bleaching is attributed to a spike in sea temperatures in May that left waters in the area about 7 degrees Fahrenheit above average.

The report, commissioned by the Wildlife Conservation Society, has yet to be peer-reviewed, but prior surveys of the reefs in the aftermath of the Indian Ocean tsunami found them to be largely intact.

Coral bleaching occurs when environmental stresses like excessive heat cause coral to expel the algae with which they normally coexist. If the bleaching is severe enough, coral can die from a lack of the energy and oxygen that the algae provide.

“This is a tragedy not only for some of the world’s most biodiverse coral reefs, but also for people in the region, many of whom are extremely impoverished and depend on these reefs for their food and livelihoods,” Caleb McClennen, marine program director for the Wildlife Conservation Society, said in a statement. “It is another unfortunate reminder that international efforts to curb the causes and effects of climate change must be made if these sensitive ecosystems and the vulnerable human communities around the world that depend on them are to adapt and endure.” Steadily warming seas pose a similar threat to reefs in other areas, environmentalists warned. This year bleaching events were recorded in Sri Lanka, Thailand, Malaysia and other parts of Indonesia.

John Collins Rudolf
New York Times News Service

A challenge for fishermen
For fly fishers who pride themselves on a conservationist ethic, it hurts to discover that they may be trampling on that ethic every time they wade into a trout stream. Blame their boots — or, more precisely, their felt soles. Growing scientific evidence suggests that felt, which helps anglers stay upright on slick rocks, is also a vehicle for noxious microorganisms that hitchhike to new places and disrupt freshwater ecosystems. That is why Alaska and Vermont approved bans on felt-soled boots and Maryland plans to do so soon. “If you were trying to design a material to transport microscopic material around,” said Jack Williams, an expert on invasive species with the environmental group Trout Unlimited, “felt on the bottom of someone’s boots in a stream would be as close to perfection as you could find.”

The response among fishermen threatened with the loss of soles parallels the five stages of grief. John Berry, a fishing guide in Cotter, Ark., switched to studded rubber-soled waders this year, after the streams near his house, by the White River in the Ozark Mountains, became infected with Didymosphenia geminata, or didymo. A single-celled organism also known as rock snot, didymo has done as much as any invasive species to prompt calls for a ban on felt soles. Bans or no bans, it can be a challenge to separate an angler from his felt soles when he believes the alternative is a bath in an icy stream.

Felicity Barringer
New York Times News Service

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