Wildfire and sedimentation could help Gila trout make a comeback


After the nearly 300,000-acre Whitewater-Baldy fire tore through the Gila Wilderness last summer, biologists from the U.S. Fish and Wildlife Service and the U.S. Forest Service geared up for a trek into the freshly burnt mountains. The team traveled to remote tributaries of the Gila River to collect any Gila trout, one of New Mexico’s threatened fish species, that had survived the initial blaze. The approaching monsoon season would likely mean death for any remaining fish, as rain would erode the fire-scarred land, flooding the streams with suffocating ash and soil. The rescued fish were flown by helicopter to a hatchery in northern New Mexico where they will stay until the streams can support them again.

This all may sound like bad news, but for the Gila trout, there is a silver lining. A flood of sedimentation following the fire cleared the streams of the non-native rainbow and brown trout that are serious obstacles to improving Gila trout populations.

Jill Wick, Gila trout biologist with the New Mexico Department of Game and Fish, is part of the team assessing the impact of last summer’s fire. She says the fish die-off is a double-edged sword.  Previous work the team had done was lost, with the fire wiping out entire populations of Gila trout. On the other hand, with the rainbow and brown trout removed from the streams, biologists will be able to reintroduce captive-bred Gila trout and expect a better survival rate.

The plight of the Gila trout sounds like that of so many other protected species: human activity on the landscape, habitat degradation, and introduction of exotic, competitive species like rainbow and brown trout have all contributed to its decline. Wick has been working closely with the scientists within the U.S. Fish and Wildlife Service, the Gila National Forest, and from the University of New Mexico -- a group she calls the recovery team -- to understand the Gila trout’s habitat needs and maintain captive breeding populations for reintroduction.

The Whitewater-Baldy fire was one of the most recent incidents in a decades-long story of Gila trout recovery work. In 1966, populations were small and precarious enough to be considered federally endangered. Under a management plan, the fish rebounded enough that in 1996, the species was down-listed to threatened.  Some members of the recovery team have been working on the project for more than 20 years, conducting captive breeding programs in northern New Mexico and building physical barriers along portions of streams to isolate wild populations from predation and hybridization with non-native rainbow trout.

The Gila trout isn’t the only species to benefit from a wildfire silver lining. Though wildfires consume many Westerners’ thoughts and government resources each summer, many Western ecosystems have actually evolved with fire, with certain tree species like lodgepole pine and aspen benefiting from heat and thinning from moderate fires. Some vertebrate species, like the black-backed woodpecker, thrive in the unique habitat created by burn areas. Still, the trend toward bigger, hotter fires poses challenges.

Year after hot, dry year, new fires across the West steal previous years’ titles as the biggest or the most destructive. In 2011, the Las Conchas fire in New Mexico’s Jemez Mountains became the state’s largest fire at 156,593 acres. The following summer, the Gila’s Whitewater-Baldy nearly doubled the number, burning out at 297,845 acres. Meanwhile, the Little Bear Fire destroyed 254 buildings across the state near Ruidoso, N.M., also last summer, earning the label “most destructive.”

As the Gila trout recovery team makes key decisions later this summer, the potential for future fires may enter the discussion, Wick says. The first management plans were written “before anyone anticipated that you could have a 300,000 acre fire,” she says. Other ecologists are anticipating significant changes to forest structure due to climate change as well and are needing to make management plans with those predictions in mind. Wick and her team are still trying to figure out what a changing climate might mean for their project.

Another challenge for the recovery team is access to habitat. It’s harder for them to manage rainbow and brown trout on streams that pass through private land and towns, as access and management techniques are restricted. Whitewater Creek, which flows through the town of Glenwood, N.M., is one such area. The creek begins on land that experienced some of the hottest burn. Closer to the Catwalk National Recreation Area, where the fire was less severe, Wick says the entire fish population was lost. And in a way, this is good news. The creek is attractive to the recovery team, with 14.5 kilometers of potential Gila trout habitat. However, it wasn’t feasible to remove the non-native trout because of its location near human populations. The die-off from the fire has done that for them, says Wick. “It couldn’t have been done any other way.”

Katie Mast is an editorial intern at High Country News.

Rex Johnson Jr
Rex Johnson Jr
Jul 16, 2013 06:29 PM
Sad to say, the basic obstacle against the recovery of the Gila trout is the trout, itself. I'll be brief with one or two points.

Reintroduced populations of Gila trout have shown, time and again, a seeming inability to extend their occupied habitat, and increase their numbers.

For instance, White Creek, a tributary of the West Fork of the Gila River and one of the very best trout habitats in the entire Gila watershed, received a planting of about 250 trout in the early 1990's, after a destructive fire which eliminated all of the wild rainbow and brown trout. The plant was made in the vicinity of Halfmoon Park, near the head of the stream. If these fish had been either rainbow or brown trout they would have undoubtedly spread over the next 20 years to re-occupy the entire upper West Fork watershed. Instead they remained in place, as one "pod", actually decreasing in number a bit.

Similarly, the Gila trout in South Diamond Creek have remained in one or two "pods" with total population of about 200 fish,which some years occupy a small tributary ("Burnt Canyon"), some years a spring hole above the canyon, some years a short distance below the canyon, even though the stream has been ungrazed for nearly a decade, has healthy riparian vegetation and several miles of apparently excellent trout habitat. The Gila trout placed many years ago in Dude Creek, under the Mogollon Rim in the Tonto National Forest, have never been able to reproduce. There are several other examples of a "failure to thrive" on the part of the "Gila trout", so-called, that are now being placed in the streams of the Mogollon Mountains, Bradshaw Mountains, the Blue Range, and other localities.

Now, if any pre_Columbian trout population in what is now the western United States would have needed to be good "colonizers", it certainly would have been the native trout of the Gila River.

so, what happened? I think, quite simply, that the hundreds of thousands of "Gila trout" now being raised, devolved, denatured and domesticated in the Mora National Fish Hatchery in northern New Mexico, then "dumped" in campgrounds in the Gila National Forest, are significantly different from the original trout which once swam in the Gila River, especially in respect to their being able to survive in the wild. In short, I believe the Gila trout is functionally extinct, and all attempts to re-develop healthy populations are doomed to fall short. The only possible bright spot in the picture, I believe are the populations of slightly hybridized and genetically invigorated gilas that still survive in a few small streams such in the Gila Wilderness. and finally, since the Arizona "Apache trout" is virtually the same species as the Gila trout and is in much better shape, perhaps the gap in trout populations in the Gila can be filled by plantings of apache trout proven to be able to survive in the wild.
James Brooks
James Brooks
Jul 19, 2013 12:12 PM
The following comments are provided in response to Mr. Johnson's comments:

1. Nonnative trout were eliminated in White Creek by use of piscicide in 1990-1991, not fire, and Gila trout of the Main Diamond lineage were introduced afterwards. Those Gila trout thrived and spread throughout the habitable stream, occupying more than 9 stream miles. The recent Whitewater-Baldy fire has since eliminated Gila trout from that stream and efforts are currently underway to assess long-term impacts of post-fire flooding to White Creek for use in future Gila trout conservation efforts.
2. South Diamond Creek holds a relic population of Gila trout that is genetically distinct. This population has historically occurred in about 2 miles of stream, including Burnt Canyon, but expands and contracts as stream flows change with climatic conditions and other effects, such as post-wildfire impacts. After a series of wildfires in 1989 and the mid 90s, this population was severely impacted including elimination from Burnt Canyon and the upper portion of South Diamond Creek. Three weeks ago we sampled South Diamond Creek and found Gila trout in less than 1/2 mile of stream. Much of the stream was dry, including Burnt Canyon. This population has historically expanded and contracted with local conditions and this population has always been able to re-colonize suitable habitats once they become available. Mogollon Creek supports a large population of Gila trout of the South Diamond linage, a population that was established using wild and hatchery-produced fish after non-native trout were removed via piscicide in 1995-6. We recently collected 200 Gila trout from Mogollon Creek for use in hatchery production efforts to ensure maintenance of genetic diversity.
3. Dude Creek is a stream in the Verde River drainage in central Arizona and an introduced population of Gila trout was eliminated by the Dude Fire in 1989. To this day, Dude Creek continues to recover from the effects of that fire and is considered to be of poor quality for any trout species.
3. As to genetics and hatchery propagation and Gila trout fitness, there is a far different and more accurate story to tell. Considerable effort has been implemented to protect the genetic diversity of five distinct lineages of Gila trout (Main Diamond, South Diamond, Whiskey, Iron, Spruce). This has included a) routine infusion of wild fish into the broodstock, b) restoration of metapopulation dynamics (large and diverse drainages with connected streams and multiple lineages) and c) protection and perpetuation of all relic lineages. Hatchery propagation is carefully controlled to minimize genetic drift and maximize genetic contribution of the entire broodstock to any stocking in the wild.

There are certainly examples of where introduction failed (Sheep, Corral, Sacaton, and Gap creeks) and all of these examples occurred in streams that were fishless prior to introduction of Gila trout. Any stream that previously contained non-native trout and has since been replaced with Gila trout has resulted in successful establishment of a Gila trout population.

Regardless of what some might think, the Gila trout recovery program has been and continues to be highly successful and responsive to changing environmental conditions. Fish that are stocked are genetically fit and have supported successful introductions in streams of the West and East forks of the Gila River, the San Francisco River in eastern New Mexico and more recently in the Pinaleno Mountains of eastern Arizona. Recent wildfires are certainly an obstacle to ultimate recovery, but the ongoing recovery strategy for Gila trout is designed to address such impacts and elimination of a Gila trout population by fire cannot be considered a failure of the recovery strategy.
Jim Brooks
U.S. Fish and Wildlife Service
Albuquerque, NM
Rex Johnson Jr
Rex Johnson Jr
Jul 22, 2013 07:15 PM
Hi Jim,
Yes,we have indeed seen many, many explanations and justifications over the years for the rather spectacular failure of the Gila trout recovery. The more things change, the more things stay the same.
James Brooks
James Brooks
Jul 26, 2013 01:08 PM
Amazing observation on your part. We must be talking about different animals, given your misinformation about Gila trout.