Monday, December 13, 2021

Wetlands point to extinction problems beyond climate change

Sat, December 11, 2021



It's not just climate change that's driving extinctions: Wetland mismanagement is endangering 40,000 small but vital plant and animal species, according to the Center for Biological Diversity (CBD).

A recent study by the International Union for the Conservation of Nature (IUCN) cited by the center found that 16 percent of all dragon- and damselfly species, among many others, are at risk of extinction from factors including pesticide misuse and sewage discharge.

Wetland ecosystems around the world "are disappearing three times faster than forests," Bruno Oberle, IUCN director general, said in a statement.

"Marshes and other wetlands may seem unproductive and inhospitable to humans, but in fact they provide us with essential services. They store carbon, give us clean water and food, protect us from floods, as well as offer habitats for one in ten of the world's known species," Oberle said.

Across the United States, 85 percent of wetlands have already been destroyed by "careless planning" that has led to the extinction of species including Bachmann's warbler and the ivory-billed woodpecker.

Wetland species face a thousandfold risk of extinction compared to others, the CBD says.

Few of the species in question are household names, but many serve as key foundations in local ecosystems, with their absence risking broader collapses.

Populations of rabbitsfoot mussel a native of the Great Lakes and the Ohio River drainage basin, which has been reduced to about half its former range, are in danger from a planned increase in sewage discharge into creeks outside Columbus, according to the CBD.

And a new dam planned for the Little Canoe Creek in Alabama risks wiping out the Canoe Creek clubshell, an endangered mollusk that depends on clean, pollutant- and silt-free water for survival, the CBD says.

Sewage discharge and dams are only one part of the problem: 41 percent of insect species worldwide are in danger of extinction due to the conversion of their habitats to agriculture and the accompanying massive rise in water-borne pesticides including glycophosphates and neonicotinoids, according to a 2019 study in Biological Conservation.

"A rethinking of current agricultural practices, in particular a serious reduction in pesticide usage and its substitution with more sustainable, ecologically-based practices, is urgently needed to slow or reverse current trends," the analysis said.

Ninety percent of U.S. streams tested by scientists carried pesticides or their toxic byproducts, according to a study this year by the American Chemical Society - with impacts that scientists stressed might be higher by a factor of ten "or more."

"The pesticide industry has conditioned Americans to believe the fiction that these highly toxic pesticides just magically vanish," Jess Tyler, a CBD scientist, said in a statement about that research.

The Trump administration weakened many restrictions on pesticide use in 2019, particularly by limiting scrutiny of the effects when rains flush pesticides into waterways - measures that were "antithetical to the plain language and purpose" of the Endangered Species Act (ESA), according to legal filings from ten state attorneys general.

The Biden administration pledged to reverse the Trump-era rollback of environmental protections, and in August passed new measures restricting use of the insecticide paraquat, according to the Environmental Protection Agency.

But the current administration has also defended many Trump-era pesticide policies, including an approval of the pesticide malathion that downplayed the number of endangered species it risked wiping out from 1,284 to 78, according to nonprofit news service Investigate Midwest.

Three overlapping bills, meanwhile, aim to confront America's extinction crisis.

The Extinction Crisis Emergency Act, sponsored by Democratic Reps. Marie Newman (Ill.) and Jesús Garcia (Ill.), would declare a national emergency around wildlife extinctions and direct all federal agencies to protect species and preserve habitats.

The Recovering America's Wildlife Act, sponsored by Rep. Debbie Dingell (D-Mich.), would provide funds to states and tribes to keep populations of threatened species from declining to the point that they need ESA protections.

And the Extinction Prevention Act, co-sponsored by Sen. Richard Blumenthal (D-Conn.) and Rep. Raúl Grijalva (D-Ariz.) would provide specific federal funding to the most-imperiled - but "least charismatic" - species in America, including butterflies, desert fish and freshwater mussels.

The new studies highlight a point with implications far beyond wetlands: Climate change is but one component in a far broader extinction crisis.

Recounting a friend's paper "about the extinction of Monte Verde golden toad," University of Arizona researcher Emily Schultz, working on a separate analysis, was left with a question: "Was it climate or was it the invasive chytrid fungus that caused frogs worldwide to go through massive die-offs? The bottom line, for the Monte Verde golden toad, was that it was an interaction between the two. The extreme drought year they had then reduced the size and number of the pools the frogs were found in. Because they were crowded into smaller pools, they transmitted the fungus more rapidly."

The way that climate and nonclimate factors stacked on top of each other suggested "that we're running out of time to save wildlife and ultimately ourselves," Tierra Curry, a senior scientist at the CBD, said in a statement.

"The Biden administration has to muster the political will to move away from dirty fossil fuels, change the toxic ways we produce food, curtail the wildlife trade and halt ongoing loss of habitat. We actually can do these things," she added.

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