in the west today can be genetically traced to the Grebe Lake stocks. Grebe Lake was closed to fishing until 1944 because of the fish culture operations at the lake. Life cycle Fluvial Montana grayling spend their entire life cycle in riverine environments. They make seasonal migrations within the river system for spawning, feeding and overwintering. Migrations of up to have been documented. Grayling inhabit cold, freestone streams having low to intermediate gradients. Adult fluvial grayling prefer pool habitats. In Montana, they spawn from late April to mid-May by depositing adhesive eggs over sand and gravel without excavating a redd. Eggs mature and hatch within a few weeks. Juvenile grayling are weak swimmers and prefer rearing habitat along stream margins that serve as velocity refuges, back-waters in side channels, or waters adjacent to beaver dams. Grayling in Montana typically reach maturity in their third or fourth year of life, and seldom live beyond six years. grayling, including juveniles are opportunistic feeders and routinely feed on larval, pupal and adult forms of aquatic insects (typically caddisflies, stoneflies, mayflies and aquatic diptera). They also consume adult forms of terrestrial insects (typically ants, beetles, grasshoppers and crickets) that fall into the water. Other prey include crayfish, shrimp, and other crustaceans. The aggressive feeding behavior of grayling is linked to their pattern of habitat selection whereby they often reside in deep pools with little large woody debris that allow for efficient and opportunistic feeding by this visual predator. Adfluvial forms of Montana grayling feed and overwinter in lake environments and migrate up suitable tributary streams to spawn. Conservation Candidate Conservation Agreement with Assurances In March, 2006, the U.S. Fish and Wildlife Service established a Candidate Conservation Agreement with Assurances between the USFWS and several non-Federal entities whereby non-Federal property owners who voluntarily agree to manage their lands or waters to remove threats to species at risk of becoming threatened or endangered receive assurances against additional regulatory requirements should that species be subsequently listed under the Endangered Species Act (ESA). The goal of the agreement was to secure and enhance a population of fluvial Arctic grayling (Thymallus arcticus) within the upper reaches of their historic range in the Big Hole River drainage. Parties to the agreement included "participating landowners" in the Big Hole river drainage, Montana Department of Fish, Wildlife and Parks, Montana Department of Natural Resources and Conservation, and US Department of Agriculture Natural