Rare fish saved from ex­tinc­tion

The Oneida Daily Dispatch (Oneida, NY) - - History - By Dan El­liott

DEN­VER (AP) >> An­other rare Colorado River fish has been pulled back from the brink of ex­tinc­tion, wildlife of­fi­cials said Thurs­day, the se­cond come­back this year for a species unique to the South­west­ern U.S.

The U.S. Fish and Wildlife Ser­vice rec­om­mended re­clas­si­fy­ing the an­cient and odd-look­ing ra­zor­back sucker from en­dan­gered to threat­ened, mean­ing it is still at risk of ex­tinc­tion, but the danger is no longer im­me­di­ate.

The As­so­ci­ated Press was briefed on the plans be­fore the of­fi­cial an­nounce­ment.

Hun­dreds of thou­sands of ra­zor­backs once thrived in the Colorado River and its trib­u­taries, which flow across seven states and Mex­ico.

By the 1980s they had dwin­dled to about 100. Re­searchers blame non-na­tive preda­tor fish that at­tacked and ate the ra­zor­backs and dams that dis­rupted their habi­tat.

Their num­bers have bounced back to be­tween 54,000 and 59,000 to­day, thanks to a mul­ti­mil­lion­dol­lar ef­fort that en­listed the help of hatch­eries, dam op­er­a­tors, landown­ers, na­tive Amer­i­can tribes and state and fed­eral agen­cies.

“It’s a work in progress,” said Tom Chart, di­rec­tor of the Up­per Colorado River En­dan­gered Fish Re­cov­ery Pro­gram. “We get more fish out in the sys­tem, they’re show­ing up in more places, they’re spawn­ing in more lo­ca­tions.”

Chart’s pro­gram over­sees the cam­paign to res­tore the ra­zor­back sucker and three other fish, all of them found only in the Colorado River sys­tem.

In March, the Fish and Wildlife Ser­vice rec­om­mended chang­ing the hump­back chub from en­dan­gered to threat­ened. It takes 18 to 24 months to com­plete the process, in­clud­ing a pub­lic com­ment pe­riod.

The ra­zor­back sucker’s name comes from a sharpedge, keel-like ridge along its back be­hind its head. Chart thinks the ridge may have evolved to help the fish stay sta­ble in the tur­bu­lent wa­ters of the Colorado.

It can grow up to 3 feet (1 me­ter) long and live up to 40 years.

Ra­zor­backs have been around for be­tween 3 mil­lion and 5 mil­lion years, but trou­ble ar­rived as the pop­u­la­tion ex­panded in the South­west. State and fed­eral agen­cies be­gan in­tro­duc­ing game fish into the Colorado with­out re­aliz-

ing they would de­vour the na­tive fish, Chart said. A spurt of dam-build­ing was a boon to cities and farms but in­ter­rupted the nat­u­ral spring­time surge of melt­ing snow, which in turn shrank the flood­plains that pro­vided a safe nurs­ery for young ra­zor­backs.

Dams also made parts of the rivers too cold for ra- zor­backs, be­cause they re­lease wa­ter from the chilly depths of reser­voirs. And they blocked the nat­u­ral mi­gra­tion of the fish.

By the late 1980s, most of the wild ra­zor­backs were old, an omi­nous sign they were no longer re­pro­duc­ing, Chart said. The Fish and Wildlife Ser­vice be­gan cap­tur­ing the re­main­ing wild ra­zor­backs and mov­ing them to hatch­eries to be­gin re­build­ing the pop­u­la­tion.

The agency des­ig­nated ra­zor­backs an en­dan­gered species in 1991, although Utah and Colorado en­acted state pro­tec­tions ear­lier.

Bi­ol­o­gists be­gan re­stock­ing rivers with hatch­ery-raised ra­zor­backs in 1995. Now, about 55,000 are re­leased into the Colorado and its trib­u­taries an­nu­ally.

The Fish and Wildlife Ser­vice be­gan work­ing with dam op­er­a­tors to time wa­ter re­leases to help ra­zor­backs spawn and res­tore flood plains for them to ma­ture. Some dams were mod­i­fied to help ra­zor­backs to get by.

Wildlife of­fi­cials be­gan rein­ing in non-na­tive preda­tor fish with nets and screens to keep them from es­cap­ing reser­voirs, or re­mov­ing them by elec­trofish­ing — stun­ning them with elec­tric­ity and eu­th­a­niz­ing them with an over­dose of anes­thetic.

Chang­ing the fish from en­dan­gered to threat­ened will al­low more flex­i­bil­ity in the way it is pro­tected, said Kevin McAbee, deputy di­rec­tor of the re­cov­ery pro­gram.

Un­der en­dan­gered sta­tus, in­di­vid­ual fish have to be pro­tected, but threat­ened sta­tus means bi­ol­o­gists can take steps to im­prove the over­all pop­u­la­tion even if some fish might be hurt, McAbee said.

Ra­zor­backs still face chal­lenges. The first-year sur­vival rate of hatch­ery fish, each roughly 14 inches (36 cen­time­ters) long, is about 20 per­cent or less in the wild, Chart said. It climbs to 80 per­cent af­ter that.

Drought, cli­mate change and in­creas­ing hu­man de­mand are strain­ing the rivers, which makes it harder for fish to sur­vive.

McAbee said the Fish and Wildlife Ser­vice took the river’s un­cer­tain fu­ture into ac­count be­fore rec­om­mend­ing the change for the ra­zor­backs. Their long life­span helps them en­dure low-wa­ter years when few young fish sur­vive, he said.

Co­op­er­a­tion among wa­ter users in 2018, a year of dev­as­tat­ing drought in much of the South­west, shows the ra­zor­backs’ needs can be ac­com­mo­dated, McAbee said.

“Things could have been cat­a­strophic,” he said.

Tay­lor McK­in­non of the Cen­ter for Bi­o­log­i­cal Di­ver­sity is doubt­ful about how healthy the ra­zor­backs re­ally are.

The gov­ern­ment’s reli- ance on hatch­eries to boost the pop­u­la­tion shows they are not self-sus­tain­ing, he said, and he wor­ries about their fu­ture in the over­taxed Colorado River.

“I think the ele­phant in the room right now with re­gard to re­cov­ery is cli­mate change and river flows and re­gional arid­i­fi­ca­tion,” he said.

“We’re skep­ti­cal of the mer­its of this,” McK­in­non said.


In this Tues­day, Oct. 2, 2018photo, a Colorado River ra­zor­back sucker fish is shown swim­ming in a tank at the U.S. Fish and Wildlife Ser­vice of­fice in Lake­wood, Colo. Of­fi­cials say that the rare Colorado River fish has been pulled back from the brink of ex­tinc­tion, the se­cond come­back this year for a species unique to the South­west­ern United States.


In this Tues­day, Oct. 2, 2018, photo, Tom Chart, di­rec­tor of the Up­per Colorado River En­dan­gered Fish Re­cov­ery Pro­gram, checks a tank con­tain­ing a ra­zor­back sucker fish on dis­play at the U.S. Fish and Wildlife Ser­vice of­fice in Lake­wood, Colo.


This un­dated photo pro­vided by the U.S. Fish and Wildlife Ser­vice shows Katie Creighton of the Utah Divi­sion of Wildlife Re­sources and Bran­don Al­brecht, of Bio-West, a gov­ern­ment con­trac­tor, hold­ing two large ra­zor­back suck­ers col­lected from Lake Pow­ell, a reser­voir on the Colorado River. Ra­zor­back suck­ers are an en­dan­gered fish found only in the Colorado River and its trib­u­taries. Fed­eral of­fi­cials said Thurs­day, Oct. 4, 2018, the ra­zor­back sucker pop­u­la­tion is grow­ing and that they will rec­om­mend that the fish be re­clas­si­fied from en­dan­gered to threat­ened.

Newspapers in English

Newspapers from USA

© PressReader. All rights reserved.