Endangered fish

News from the Colorado River Basin demonstrates that the ESA is working

Over the 45 years of its life, the Endangered Species Act may have generated as much scorn as support.

And right from the start: The ESA faced its first Supreme Court test in 1973 – the same year it was enacted – when protections for the snail darter, a diminutive fish found only in the Little Tennessee River, temporarily halted completion of the Tellico Dam with construction over 95 percent complete.

Now as then, the act’s critics deride it as an anti-development weapon wielded by environmentalists, while supporters hail it as an essential means to keep plant and animal species from vanishing.

There are many ESA success stories, including American alligators, whooping cranes and California condors. There were just 27 of the condors in 1987, all in captivity, but a viable wild population has since been reintroduced to northern Arizona and southern Utah.

The ESA process is no guarantee: 10 species have gone extinct after being listed. And it can take decades, though not always. The status of the Lake Erie watersnake, thanks to cooperation from federal, state and local partners, went from “threatened with extinction” to “fully recovered” in a remarkably short 12 years.

Closer to home, there is good news concerning the humpback chub and the razorback sucker, two of four fish native to the Colorado River system listed as endangered species (the Colorado pikeminnow and the bonytail are the others).

Loss of habitat from dams and diversions, predation from non-native fish and the disruption of water flows necessary for spawning have been blamed for the demise of the fish, all of them notable not only for their abundance and large size but for amazing longevity. The Colorado pikeminnow, once a favorite food of native tribes, settlers and miners – it was known as “San Juan Salmon” – can reach 6 feet in length, 80 pounds and live for 40 years.

In March, the U.S. Fish and Wildlife Service announced plans to change the status of the humpback chub from endangered to threatened because the population has rebounded. The recovery is thanks to efforts by hatcheries, dam operators, private landowners, Native American tribes and state and federal agencies, all coordinated through the Upper Colorado River Endangered Fish Recovery Program.

More recently, officials announced the existence of a previously unknown population of razorback suckers below a waterfall on the lower San Juan River. From 2015 to 2017, some 1,500 razorbacks, which are hatchery-raised and tagged before being released, were located below the fall. That is significant; the overall razorback population is estimated at no more than 4,000 fish.

What’s more, the razorbacks were not all from the hatchery upstream in Farmington. Some migrated from the White and Gunnison rivers, making an epic journey down to the Colorado River and across Lake Powell before running up the San Juan to the base of the falls. That information surprised researchers, who had assumed the razorback to be a much more sedentary species.

But these discoveries are not the point in writing in support of the ESA. The point is much broader than that.

In 2018, without the act, it is doubtful that any razorback suckers would exist at all, much less be found in numbers large enough to delight a fish biologist.

The ESA is working.



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