Saturday, November 09, 2013

The long journey of the Gila trout

by Katie Mast
 
A caravan of mules and horses follows a stream-side trail lined with spring-green cottonwoods and alders through New Mexico's Gila National Forest. Some of the mules carry two metal boxes secured to their sides with thick purple webbing, and each box houses roughly 75 fish in water that sloshes throughout the five-mile trek. One set of panniers weighs roughly 150 pounds and can throw off the mule's balance at the trail's river crossings. "If you're behind them, you can tell it's not easy," says Jill Wick, a trout biologist with the state's Department of Game and Fish.

While the experience is cumbersome for the mules, it's nothing short of bizarre for the threatened Gila trout, a small, freckled, golden fish that has been pushed to the brink by introduced game fish. Its existence now depends on a carefully orchestrated, human-assisted loop tacked onto its lifecycle.

Each spring after the Gila trout spawn, members of the trout recovery team travel to the headwaters of the Gila River in the state's southwestern corner. Wearing waders and heavy backpacks with 24-volt battery systems, they shock the water and collect a variety of young and older stunned fish that rise to the surface to use for captive breeding.

This abduction is stressful for the fish, triggering an adrenaline rush and changes in blood chemistry. So the biologists doctor the panniers' water with medicine, aerate with oxygen and carefully regulate the temperature. At streams up to five miles from roads, the fish ride out on mules. Deeper into the wilderness, they fly out suspended from a helicopter's belly in a large metal box.

The final leg of this unusual journey is a 400-mile truck ride on Interstate 40 to a hatchery in Mora, N.M. The trout's offspring eventually help rebuild populations in new mountain streams, but after two years of well-fed life, the trophy-size adults are too big to return home. At 22 inches, they couldn't survive in the trickle that fills the headwaters, so they are returned to lower elevations near the river's main stem.



1 comment:

Anonymous said...

Not likely to be pond scum. More likely too many elk and too little forage and someone else wanted the forage. Why so many elk in one herd in August? It had been raining in NM and the elk should have dispersed on the newer forage. 100 elk in one herd is more like a winter herd not a summer herd.