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Nestled in the shadow of the Caribou Mountains in southeast Idaho, Grays Lake National Wildlife Refuge encompasses a 22,000-acre bulrush marsh surrounded by productive wet meadow and grassland habitat. This high mountain basin hosts the highest breeding density of sandhill cranes in North America and also many breeding and migrating ducks, Canada geese, trumpeter swans, Franklin's gulls, white-faced ibis, and other waterbirds.

Throughout the basin's history, ranchers have grazed the meadows and grasslands, and in recent years refuge managers have used grazing as one of their principle habitat management tools. In 1996, the FWS developed a new strategic plan for managing wet meadow/grassland habitats to address concerns about the compatibility of grazing with refuge objectives. The strategy proposed a combination of management practices: summer grazing, fall grazing, fall prescribed burning, haying, and idling.

Under an FWS-USGS research partnership, scientists at the Northern Prairie Wildlife Research Center in Jamestown, North Dakota, have worked cooperatively with refuge managers since 1996 to develop a comparative study using measures that pertain directly to the goals and objectives of the refuge. The overall objective of the study is to assess the relative values of four regimes to manage biological resources of the meadow ecosystems on Grays Lake.

The pre-treatment field work has already provided valuable information to the refuge. Analyses of 1997 field data show direct relationships between plant community composition and the lake level. Basic data on the biodiversity of the Grays Lake ecosystem–information that had not been previously available to the refuge staff–has now been catalogued. More than 200 plant species have been found, along with species lists for birds, small mammals, and predator communities. The distribution of the major predators of nesting birds–coyotes, red foxes, eagles, ravens, and skunks–also has been documented.

The Fish and Wildlife Service will use the results of this large-scale experiment to select management methods that best meet the objectives for the Grays Lake National Wildlife Refuge. The partnership between USGS researchers and FWS managers has successfully conducted research with direct applications to refuge management.