Trout and Native Fish Conflicts in the Grand Canyon

trout-12.jpgTrout and Native Fish Conflicts

Perceived conflicts between Trout and native fish in Arizona have led to real conflicts between Trout, government agencies and environmental groups. These conflicts are shaping up to be a battle ground between sportsmen and science and government… Powerful and well-funded environmental groups are leading the charge against anything “non-native” that swims in western waterways. Through the court system and activism, these groups are shaping policy that will have a long ranging affect on sport fishing as we know it today.

In the vision of Teddy Roosevelt, the National Park Service stocked Trout in Colorado River Tributary creeks in the Grand Canyon from 1923 until 1964. The cold side streams were a perfect habitat for these non-native sport fish and the Trout thrived. In 1963, the gates to Glen Canyon Dam were closed and the Colorado River changed from a silt laden, warm river, to a cold and clear stream. Most of the native fish that lived in this stretch could not handle the new conditions. Meanwhile, Rainbow Trout were stocked directly below the dam at Lees Ferry. Anglers from around the world soon discovered the tremendous angling opportunity that this river offered and flocked to Lees Ferry. Local infrastructure grew to accommodate the millions of dollars that these anglers brought to our area to spend…guide services, lodges, restaurants, and retail shops thrived on the sport fishing dollar. These dollars have been especially precious to the local economy, which includes the northwestern section of the Navajo Reservation. According to The National Geographic Society, this area has the lowest per-capita income of any area in the United States.

A few years back, the political winds shifted and the fish that no one had seen in years became the hero and Trout became the villain. Environmental groups and scientists had begun to speculate that the reason these native fish were disappearing from the Colorado River was that those evil Trout were eating all the native fish. Forget for a moment that the native habitat had been radically altered by the dam, that there was now clear cold water, that the food chain had changed…it just has to be those pesky and voracious Trout that were eating and out competing the native fish! The scientists even had produced proof that this was the case…they were killing Trout and sampling their stomachs and found fish in the stomachs of Rainbow Trout. When we pressed for specifics, we were told that of the thousands of Rainbow Trout killed, less than 1% (LESS THAN ONE PERCENT!!!) of the Rainbow Trout had fish (unidentifiable but probably suckers and not endangered fish) in their stomachs. Fifteen percent of the Brown Trout killed (less than 500) had fish in their stomachs. We concede that Brown Trout can be predatory, but to have Rainbow Trout lumped together and made a public enemy is irresponsible.

The Trout have been accused (without proof) of eating the 500,000 juvenile native Humpback Chubs a year that are flushed by monsoon rains out of the Little Colorado River into the Grand Canyon. Starting in 2003, six times a year, for four years, Trout were killed by the Grand Canyon Monitoring and Research Center (GCMRC) scientists, in a 17 mile section of the Colorado River in the Grand Canyon approximately 60 miles downstream of Lees Ferry at a cost of 4 Million Dollars. Predictions in 2002 were that one million trout lived in the Grand Canyon and that 70,000 Trout lived in the 17 mile stretch by the LCR. They thought there must be way too many Trout and they must be eating or crowding out the native fish. The GCMRC claimed a 90% killing effectiveness, yet in four years and 24 trips they killed just 20,000 Trout. Obviously there were many fewer Trout in the Grand Canyon than GCMRC thought…somebody screwed up and overestimated the trout population by a factor of 7 times. In the mean time, millions of dollars were spent seeking a solution to a problem that did not exist in the first place. The Trout killing experiment was for four years and now will be “shut off” for four years. The scientists from GCMRC have said they would like to keep killing Trout to “continue collecting data”.

In 1992 the U.S. Congress passed the “Grand Canyon Protection Act” and created the Glen Canyon Dam Adaptive Management Work Group (AMWG). The AMWG is 26 “stakeholders” including state and federal government agencies, Native American Tribes, environmental groups and recreation groups. The Federation of Fly Fishers is one of the recreation stakeholders. The AMWG has eleven goals for the Grand Canyon below Glen Canyon Dam. The goal for Lees Ferry was to reduce the Trout population from 250,000 to 100,000. And Trout now are absolutely persona non-grata in the Grand Canyon. Two other AMWG goals are to have bigger sand camping beaches and more Humpback Chubs in the Grand Canyon. The National Park Service is the most anti-Trout stakeholder in the AMWG, largely because today the NPS does not want anything non-native in the Grand Canyon. Other intensely anti-trout stakeholders are the U.S. Fish and Wildlife Service, the U.S. Bureau of Reclamation and the Grand Canyon Trust.

Humpback Chubs are warm water fish living mainly in the Little Colorado River because it is spring fed and warm (70 degrees F.) all year. There are non-native fish (Channel Catfish, Bullheads, Carp, Shiners, etc.) that also live in the LCR. Humpback Chubs in the LCR are captured and counted five times a year by the Fish and Wildlife Service and by the Arizona Game and Fish department.

Having chubs only in the LCR is not acceptable to the NPS, the FWS, the USBR and the GCT. They are insisting that chubs must live in the Colorado River as well. This is probably impossible and also very risky to the chubs living in the LCR. Warming the water released from Glen Canyon Dam would require dam modifications costing as much as 160 million dollars. Warmer water would transform the current situation of Trout in the cold Colorado River and Chubs in the warm Little Colorado River to both rivers being conducive to non-native warm water predatory fish from Lake Mead (Stripped Bass, Smallmouth Bass, Channel Catfish, Sunfish, Shinners, Etc.).

In 2003, during a NPS feasibility study using a weir at the mouth of Bright Angel Creek, 423 Brown Trout were killed. The AMWG endorsed killing Brown Trout but not Rainbow Trout. In fall 2006, the NPS started a five year project to kill Brown Trout and Rainbow Trout in Bright Angel creek. During a thirty-day comment period, the NPS received dozens of letters opposed to their killing plans. The Arizona Game and Fish department gave the NPS a permit to kill only the Brown Trout. In 2006, 212 Brown Trout were killed in 70 days. The NPS has stated they intend to kill Rainbow Trout as well, with or without an AGF permit and without regard to public comments.

GCMRC proposes “Beach Habitat Building Flows” to increase the size of camping beaches. These spring floods would occur when enough sand has come into the Colorado River from flash floods in the Paria River at Lees Ferry. GCMRC contends that the floods will also clean out “senescent” or old aquatic plants, improving fish food supplies and create better “back water” habitat for chubs. Declines in the Lees Ferry Trout Fishery have coincided with experimental flows for beach manipulation. Particularly bad examples were the year long flow experiments in 1990-91 and the very destructive flood in November 2004. A flood was proposed for March 15 in 2007, that did not happen, but a flood has been proposed for spring of 2008.

$200,000.00 has been spent by the USBR to study the feasibility of pumping four million tons of sand and clay a year from the Navajo Canyon delta in Lake Powell to the river below Glen Canyon Dam through underwater and underground pipes. The objective is to “provide cover for Humpback Chubs” by making the river continuously muddy and to make camping beaches bigger. Appraisal cost estimates for five different designs range from 110 to 400 million dollars, with annual operating costs of around 10 million dollars.

On June 2nd 2006, The Center for Biological Diversity and the environmental group Living Rivers gave formal notice of intent to sue the Arizona Game and Fish Department for violating the endangered species act if they stock Trout at Lees Ferry.

So what does all this mean to the sportsmen of Arizona? We must understand that the debacle that is occurring at Lees Ferry and in the Grand Canyon is the beginning of a movement to remove non-native sport fish from not just the Colorado River, but sport fish removal and eradication might just be coming to a river or lake near you.

WHAT CAN YOU DO? Get involved in the process, go to public meetings, and write letters to the government organizations and your politicians. Let all your friends know and urge them to join organizations like The Federation of Fly Fishers or Arizona Sportsmen For Wildlife Conservation, organizations dedicated to educating the public, advocating wise use, and protection of our wildlife resources and hunting and fishing heritage.

For more information about the AMWG and future experiment planning check out this USBR web page:

One Response to “Trout and Native Fish Conflicts in the Grand Canyon”

  1. I support no action when it come to releases from Glen Canyon Damn. Let’s embrace one of the nation’s best trout fisheries. Why try to fake something it can never be again as long as the damn remains. You would have to remove all the damns along the Colorado River system in order return the river back to its natural setting and have it support the native fish populations that once thrived there.

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