Gila Trout (Oncorhynchus Gilae) Data: Gila Trout Recovery Plan-2003 Partners: Arizona Game and Fish Department, New Mexico Department of Game and Fish, U.S
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Gila Trout (Oncorhynchus gilae) Data: Gila Trout Recovery Plan-2003 Partners: Arizona Game and Fish Department, New Mexico Department of Game and Fish, U.S. Fish and Wildlife Service, U.S. Forest Service Gila Trout Species Status review: landowners provides opportunity for The Gila Trout was originally recognized as increased Gila Trout restoration and should endangered under the Federal Endangered result in a conservation benefit to the Species Preservation Act of 1966 (U.S. Fish species. The U.S. Fish and Wildlife Service and Wildlife Service, 1967). Federal- and the State wildlife and fisheries designated status of the fish as endangered management agencies responsible for was continued under the Endangered establishing fishing regulations work to Species Act of 1973 (U.S. Fish and Wildlife ensure that angling pressure does not Service, 1975) until 2006 when the species prevent, but enhances, progress toward full was down-listed to threatened (U.S. Fish and recovery. Gila Trout angling will continue to Wildlife Service, 2006). The Gila Trout was be managed by the States as long as the listed as endangered by the New Mexico population remains above the recovery Department of Game and Fish in 1975 under threshold. the Wildlife Conservation Act and was down-listed to threatened in 1988, and Distribution of Gila Trout: The extent of remains listed as threatened by New Mexico the historical distribution of the Gila Trout is Department of Game and Fish. Gila Trout not known with certainty. It is known to be are considered a Species of Concern by the native to higher elevation streams in Arizona Game and Fish Department. portions of the Gila River drainage in New Mexico, San Francisco River drainage in Sportfishing Status of the Gila Trout: Arizona and New Mexico, and tributaries to Fishing for Gila Trout was once restricted the Gila River in Arizona. Currently, there under its status as an endangered species. are 12 populations of Gila Trout in the wild. The down-listing to threatened in 2006 Additionally, the Mora National Fish Health includes a special provision that allows the and Technology Center (U.S. Fish and states of New Mexico and Arizona to Wildlife Service) maintains captive manage the species as a sportfish in select populations of all four Gila Trout lineages. areas for the first time in almost 50 years. Guidelines have been developed to allow for limited sport fishing in specific waters Range of the Gila Trout: where stocking of non-native trout was Three of the four relict populations are self- replaced by stocking of Gila Trout. Most sustaining in the wild; the relict population restoration streams continue to be protected in Spruce Creek was eliminated following from angling. However, allowing for limited the Whitewater-Baldy Fire in 2012. With the angling for a unique native species can exception of the Spruce Creek lineage, all increase public knowledge and support for other lineages have been replicated in a its conservation. Such support may come sufficient number of drainages to minimize from both sport fishing enthusiasts and potential loss of any lineage from a natural private landowners that might benefit from or human-caused event. The Main Diamond allowing access to fishing on their property. Involvement from the general public and Gila Trout (Oncorhynchus gilae) 37,000 in 1998 and current estimates are unavailable. Gila Trout Habitat Requirements: Habitat of Gila Trout consists of perennial montane streams ranging from 1,660 m (5,400 ft) to over 2,800 m (9,200 ft) elevation. Suitable stream habitat within the range of the species is situated between about 33° to near 35° north latitude and 107° 45' to near 112° 15' west longitude. Streams with suitable habitat for Gila Trout are found in coniferous and mixed woodland, Creek population was restored to its original montane coniferous forest, and sub-alpine habitat following its loss in the wild from coniferous forest. Stream flow is the 1989 Divide Fire. Replicates of the Main characterized by a snowmelt-dominated Diamond Creek population persist in Sheep hydrograph in most years and snowmelt Corral Canyon, lower Little Creek, and runoff typically begins in February, peaks in Black Canyon. Main Diamond lineage Gila March, and gradually decreases through Trout were recently stocked in upper May. Base flow conditions prevail in June Langstroth Creek but success of this and into July. Mean monthly discharge replication has not yet been documented. characteristically increases in July through Similarly, the South Diamond Creek September coinciding with runoff from population was restored to its original convectional summer thunderstorms. habitat following its loss in the wild from Sporadic periods of runoff from winter rains the 1995 Bonner Fire. The South Diamond or mid-season snowmelt often results in Creek population is replicated in Grapevine flows slightly elevated above base levels in Creek, Frye Creek, Willow Creek, and the December and January. Gila Trout require Mogollon Creek drainage, which includes a water temperatures below 25°C (77°F), portion of the main stem of Mogollon Creek, clean gravel substrate for spawning, Trail Canyon, Woodrow Canyon, and South continuous stream flow of sufficient Fork Mogollon Creek. The Whiskey Creek quantity to maintain adequate water depth relict population was eliminated by the 2012 and temperature, and pool habitat that Whitewater Baldy Fire, but has been provides refuge during low flow conditions replicated in McKenna Creek and upper and periods of thermal extremes. Abundant White Creek. The Spruce Creek population invertebrate prey, cover, and water free from was also eliminated by the 2012 Whitewater contaminants are also required. Cover Baldy Fire but is replicated in Big Dry typically consists of undercut banks, boulder Creek. Mixed lineage populations were alcoves, large woody debris, deep pools, established in Dude Creek and Ash Creek in exposed root masses of trees at water’s edge, 2015, recruitment has yet to be documented. and overhanging vegetation. The total population size of Gila Trout in the wild was estimated to be approximately Western Native Trout Status Report – Updated February 2016 Gila Trout (Oncorhynchus gilae) Concerns, Issues, or Obstacles chemical piscicide treatments and relative to the Conservation and electrofishing. Improvement of the status of Gila Land use and management issues Trout: Forest management includes activities that Water Condition Concerns directly or indirectly affect species composition, density, and vertical structure High stream discharge variability is a of vegetation. Changes in these forest defining characteristic of the environment to variables may affect watershed which Gila Trout has adapted. During low- characteristics such as infiltration, runoff, flow years, marginal habitats may become and erosion, and stream habitat too warm to support trout or surface flow characteristics such as sediment transport, may cease and stream segments may dry. nutrient cycling, physical habitat features, Pool depth may diminish to the extent that and water temperature. Forest management winter mortality of trout is greatly increased. includes silvicultural treatments (e.g., timber Large magnitude flood events during high harvest, thinning, prescribed burning) and flow years may scour stream channels and wildfire control. Although much of the eliminate year classes of trout. These habitat of Gila Trout is within designated frequent, recurring extremes in flow wilderness where timber harvest is not conditions are a basic element of the allowed, historical logging activities likely relatively harsh environment that caused major changes in watershed distinguishes habitat of Gila Trout from the characteristics and stream morphology. typical trout streams of more northern Poorly managed livestock grazing can latitudes. Wildfire impacts and drought in degrade watershed condition, stream habitat recent years have exacerbated the impacts of and riparian environments, resulting in flow variability. decreased production of salmonids. Historically, widespread, uncontrolled Non-native Sportfish Concerns livestock grazing likely contributed to habitat degradation modifications cited as a Stocking and naturalization of non-native cause for the decline of Gila Trout. Severe trout within the range of Gila trout and forest fires capable of extirpating or ensuing hybridization, predation, and decimating fish populations are relatively competition are major causes for the recent phenomena, resulting from the imperiled status of the species. Rainbow cumulative effects of historical or ongoing Trout and Brown Trout have become overgrazing by domestic livestock and fire naturalized and are widespread within the suppression. historical range of Gila Trout. Current stocking of Rainbow Trout is conducted only in stream segments not inhabited by Natural disturbances Gila Trout, however, hybridization with Rainbow Trout remains a prominent threat Over the last decade, large scale wildfires to Gila Trout. A vital component of recovery have occurred on a more regular frequency and long-term survival of Gila Trout is than historically observed. These fires have removal of non-native trout through eliminated several populations of Gila Trout Western Native Trout Status Report – Updated February 2016 Gila Trout (Oncorhynchus gilae) and drastically altered the hydrology in unique genetic identity of the species, which many watersheds. Views of the geographic represents its evolutionary history and local