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002J44 P~ II RECOVERY The purpose of this plan is the reestablishment of pure greenback cutthroat trout to population levels where the subspecies will not likely become extinct thrcughout all or a significant portion of their historic range. OVerall, an ecosystem management approach will be used, with special considerations for impacts to listed species, other native species, water quality and public use. For a summary of previous recovery accomplishments and activities, please see Attachment 1. THE OBJECTIVE OF THE GREENBACK CUTTHROAT TROUT RECOVERY PLAN IS THE REMOVAL OF THIS SUBSPECIES FROM THE LIST OF THREATENED AND ENDANGERED SPECIES. THIS SUBSPECIES WILL BE CONSIDERED RECOVERED WHEN 20 STABLE GREENBACK CUTTHROAT TROUT POPULATIONS ARE DOCUMENTED REPRESENTING A MINIMUM OF SO HECTARES OF LAKES AND. PONDS AND SO KILOMETERS OF STREAM HABITAT WITHIN ITS NATIVE RANGE. A MINIMUM OF FIVE OF THESE POPULATIONS WILL EXIST IN THE ARKANSAS RIVER DRAINAGE. ONCE RECOVERY OBJECTIVES HAVE BEEN MET, A LONG RANGE MANAGEMENT STRATEGY WILL BE IMPLEMENTED FOR THE CONTINUED RESTORATION OF THE SPECIES. For delisting purposes, a stable self-sustaining greenback cutthroat trout population is defined as a population of greenbacks that maintains a minimum of 22 kilograms of greenbackS per hectare of habitat through natural reproduction. The population should contain a minimum of 500 adults (individuals greater than 180 mm in total leygth), and represent a minimum of two year classes within a five-year period that are established through natural reproduction. A minimum of 120 breeding pairs (240 adult fish) was considered necessary to maintain genetic diversity within a population (Leary, pers com), and the team has set a minimum of 500 adults as necessary to insure maximum genetic diversity for each wild greenback population. Twenty stable reproducing populations, along with the above population criteria, are needed to quantify an adequate population to meet the stated recovery objectives. This strategy distributed into two separate drainages (the Arkansas and the South Platte), will provide a minimum viable population goal that can be monitored and maintained. A population of greenbacks cannot be considered stable unless the population is separated by physical or biological barriers from other salmonids. Although fall-spawning trout species will not hybridize with greenbacks, the presence of brook trout and brown trout is not considered to be conducive to stable greenback populations. Fall-spawning species will most likely displace greenbacks, or prevent the greenbacks from meeting the requirements for biomass and reproduction. Highly glaciated drainages, with multiple hanging valleys, can contain more than one stable self-sustaining population. However, each stable population should contain at least two hectares of habitat that is separated by barriers to. upstream fish migration. Each stable population within a drainage must meet the previously stated requirements for biomass, population size and reproduction. The locations the team has selected for recovery sites have concentrated on headwater streams and high elevation lakes. These sites provide the most likely sites for successful recovery of this species due 1) to presence of barriers; 2) ease of removing non-native fish; 3) inaccessibility which reduces problems with reintroduction of non-native species; and 4) the fact that existing remnant populations were discovered in headwater habitats. As the recovery progresses, both larger and lower elevation habitats may be renovated. Previous editions of the Greenback Cutthroat Trout Recovery Plan identified recovery actions that have resulted in significant improvements in the status 17