Table 1. States with nonindigenous occurrences, the earliest and latest observations in each state, and the tally and names of HUCs with observations†. Names and dates are hyperlinked to their relevant specimen records. The list of references for all nonindigenous occurrences of Oncorhynchus apache are found here.
Table last updated 3/28/2025
† Populations may not be currently present.
Ecology: Apache Trout's native habitat are small cool water (< 25º C) creeks that are relatively unstable and occur, at the lowest, from 1,800 to 2,100 meters in elevation (Rinne and Minckley 1985, Behnke 2002, Arizona Game and Fish Department 2009). These creeks usually occur in mixed conifer and ponderosa pine forest (Arizona Game and Fish Department 2009). Lake populations have been stocked because there are no natural lakes occurring in the native range of the species (Behnke 2002). This species typically lives four years, but the maximum known is six years. Their diet consists of aquatic and terrestrial invertebrates (Behnke 2002). Adults are typically small in size because of their diet and habitat limitations. Apache Trout require clean coarse gravel substrates for spawning and prefer cover in the form of woody debris, pools, coarse substrate such as gravel, cobble, and boulders, undercut stream-banks or overhanging vegetation at stream edges (Arizona Game and Fish Department 2009). Spawning occurs in the spring (May) when water temperatures are rising and snow runoff into streams is lower. Temperature seems to be the critical factor to the initiation of spawning. Females lay between 70 -300 eggs based on body size (Behnke 2002).
Widely stocked non-native trout species have impacted the Apache Trout. Brown Trout (Salmo trutta) and Brook Trout (Salvelinus fontinalis) devour eggs, fingerling, and parr and out-compete Apache Trout for food and space. Rainbow Trout (Oncorhynchus mykiss) and Cutthroat Trout (Oncorhynchus clarkii) will also predate on Apache Trout and hybridize with them (Arizona Game and Fish Department 2009; Minckley and Marsh 2009).
Status: The Apache Trout Recovery Plan (2009) indicated that 27 pure (non-hybridized) Apache Trout populations exist within their historical range in Gila, Apache, and Greenlee counties of Arizona, on lands of the Fort Apache Indian Reservation and Apache-Sitgreaves National Forest. Two streams outside of historical range have pure replicate populations, North Canyon Creek (Ord Creek stock) and Grant Creek (Pinaleño Mountains) stocked in the late 1960s (Arizona Game and Fish Department 2009).
Lakes and streams outside the native waters are maintained by stocking (Behnke 2002).
References: (click for full references)
Arizona Game and Fish Department, U.S. Fish and Wildlife Service, U.S. Forest Service, Trout Unlimited, White Mountain Apache Tribe, San Carlos Apache Tribe, National Fish and Wildlife Foundation. 2009. Apache trout recovery plan. Western Native Trout Status Report.
Behnke, R.J. 1992. Native trout of western North America. American Fisheries Society Monograph 6. American Fisheries Society, Bethesda, MD.
Behnke, R.J. 2002. Trout and Salmon of North America. The Free Press, NY.
Minckley, W.L., and P.C. Marsh. 2009. Inland fishes of the greater Southwest: chronicle of a vanishing biota. University of Arizona Press, Tucson, AZ.
Rinne, J.N., and Minckley, W.L. 1985. Patterns of variation and distribution in apache trout (Salmo apache) relative to co-occurrence with introduced salmonids. Copeia 1985(2):285-292.
This information is preliminary or provisional and is subject to revision. It is being provided to meet the need for timely best science. The information has not received final approval by the U.S. Geological Survey (USGS) and is provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the information.
