ALBUQUERQUE, N.M. — It was nearly 60 years ago on the Gila River. That's the last time anyone had documented a river otter in New Mexico. A government trapper found the dead animal in a beaver trap he had set.
Now, the chance of otters making any kind of a comeback in the upper reaches of the Gila is being put on hold indefinitely by New Mexico wildlife officials, a move that is frustrating conservationists and others who see the sleek mammals as the best hope for preserving endangered fish in the troubled river.
Stretching from the mountains of southern New Mexico into southeastern Arizona, the Gila is an example of what has happened to rivers throughout the West. From choking drought conditions and habitat changes to an influx of exotic species, a number of factors have helped push populations of native fish to dangerously low levels.
It's those endangered fish that the New Mexico Game and Fish Department says it's worried about. The department contends Arizona wildlife officials and the U.S. Fish and Wildlife Service have expressed similar concerns.
Playful and highly social, otters love to eat fish.
Supporters of the reintroduction program argue the otters' first choice will be invasive crayfish and larger, slower nonnative fish like bass and carp.
"We're aware of the arguments — and I agree with a lot of the arguments — that having a species that preys on fish might actually be beneficial to some extent because of the large number of nonnative fish in the Gila," said Jim Stuart, a biologist with the department's Conservation Services Division. "But you can't tell an otter what to eat, and we do have some populations of listed fish down there that are in pretty bad shape right now. They're right on the edge."
The decision to pull the plug on otter reintroduction was spelled out in a three-paragraph letter sent recently by Stuart to members of the New Mexico River Otter Working Group.
Supporters of the program balked at the state's reasoning, pointing to Utah, Colorado, Arizona and other states that have had success in reintroducing otters, even in rivers that are home to endangered species.
They also say the letter marked the first time that Arizona's concerns had been documented by New Mexico officials. The working group has had no discussions with Arizona wildlife officials.
Melissa Savage, director of the Four Corners Institute and a member of New Mexico Friends of River Otters, said New Mexico's action flies in the face of a 2006 Game Commission decision to move forward with reintroductions on the Upper Rio Grande near Taos and the Gila River. The decision was based on a feasibility study that looked at several river systems in the state.
More than 30 otters were released into the upper reaches of the Rio Grande between 2008 and 2010 and that population seems to be holding its own. Releases on the Gila were initially planned for 2010 but the program stalled despite a biological opinion on the potential impacts and an intensive monitoring plan.
The working group, which has been funding the otter program, has already spent about $20,000 of private funds and donations on the Gila effort. The river's endangered fish are running out of time, Savage said.
"These fish populations are declining, so what is the plan? Are we going to sit here and watch them go down or are we going to try this?" she said. "We can take the otters out if it doesn't work."
Donna Stevens of the Upper Gila Watershed Alliance said otter reintroduction is "the only inexpensive and practical way" to save the Gila's native fish.
Work to return the otters to New Mexico rivers has been about a decade in the making. The animals were once plentiful in the upper and middle Rio Grande, the Gila, Mora, San Juan and Canadian river systems.
Decades of trapping and habitat loss are believed to be factors that led to their disappearance.
More than 20 states have successfully reintroduced river otters, which biologists say play an important role in keeping semi-aquatic ecosystems healthy and diverse.
It was former Game Commissioner Dutch Salmon of Silver City who requested the Gila be included in New Mexico's otter program. An avid angler who has fished the river for nearly 30 years, he doesn't believe otters would have a negative impact on the Gila's endangered species or its sport fishing.
Salmon and others said the department's decision may be based more on the politics of managing game species.
"It's a potential snowball fight between user groups," Salmon said. "I think it's an issue the department would just as soon avoid."
For now, Stuart said he hopes to ramp up monitoring of otters in the Upper Rio Grande and those that have been spotted on the San Juan River in northwestern New Mexico, which are believed to be transplants from release efforts in Utah and Colorado.
Stuart also pointed to the success of otters in Utah, which has a large enough population to allow for relocation to other river systems within that state.
"Whether we ever get to that point and have the opportunity to move them to another drainage remains to be seen," he said. "That's one reason to focus on making sure you've got them established in at least one system."
Follow Susan Montoya Bryan on Twitter: http://www.twitter.com/susanmbryanNM