The #ColoradoRiver Is Dying. Can Its Aquatic Dinosaurs Be Saved? — Mother Jones Magazine #COriver #aridification

Click the link to read the article on the Mother Jones website (Stephanie Mencimer). Click through and read the whole article, here’s an excerpt:

Found nowhere else in the world, the native razorback has occupied the waterways of the Colorado River basin for at least 3 million years, one reason why Olsen says they’re known as the “dinosaurs” of the Colorado. Known as “detritivores,” the bottom-feeding fish were once an important part of the river’s food chain because they nosh on dead plant and animal matter that might otherwise build up and cause disease while returning essential nutrients to the ecosystem. The fish have adapted to the harsh monsoon-to-drought cycles of the desert rivers that flood with melted mountain snowpack in the spring and are parched in the late summer. Razorback suckers can grow up to three feet long, 80 pounds, and live for 50 or 60 years. But such geriatric monster fish are rare in the wild today.

The native fish have not fared so well over the past century since humans began trying to make the western desert bloom by damming the Colorado and its tributaries, a watershed that was once one of the most biologically diverse in North America. “They’re a bellwether for the health of the entire river ecosystem, from Wyoming to the Gulf of California,” says Taylor McKinnon, senior public lands advocate at the nonprofit Center for Biological Diversity…

The US Fish and Wildlife Service first listed the razorback as endangered in 1991, and the species would be extinct in the Upper Basin but for the hatchery program, which was established in 1996 as part of the Upper Colorado River Endangered Fish Recovery Program and is funded by the US Fish and Wildlife Service. The program has been successful enough that last year, FWS proposed downlisting the razorback from “endangered” to merely “threatened” under the Endangered Species Act. But the extreme mega-drought of the past two years makes that proposal seem wildly optimistic…

Meanwhile, the biggest ongoing threat to the Colorado’s endangered fish is other, nonnative fish. Only 12 fish are native to the Upper Colorado River Basin, Breen says. But now more than 50 species compete in the rivers. Many that were intentionally introduced to promote sport fishing are highly predatory in a way the razorback and others have not evolved to survive…The recovery program spends more than $2 million a year trying to eliminate the non-native fish from the Green River and elsewhere in the system—a move that is not always popular with local anglers who like to fish for the bass. “For the record: I love smallmouth bass,” says Breen. “I grew up fishing for smallmouth bass in the Midwest. But that’s where they’re supposed to be. Bass are very predacious, and they’re not supposed to be in that river.”

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