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Flight Procedures Fixed-wing aircrafts were flown between 300-350 feet at 90-100 mph. • Helicopters were flown at an altitude of 150-200 feet and an air speed of 60-70 mph. A mapper/navigator accompanied the spotter whenever pos- sible. The same pilot consistently flew each route in order to minimize between-flight differences. A11 routes were flown between 8:00 - 12:00 a.m., weather permitting. The San Miguel and Gunnison Rivers were also flown at dusk (1-1~ hours before dark) to determine night concentration areas. The San Miguel River was flown the morning following the first of these evening flights to determine the fluctu- ation in eagle use between these periods. During each flight the following information was recorded: temperature, Kind speed, average aircraft altitude and speed, and starting/landing times. When an eagle was sighted, age class, location, activity and time were recorded. Each sighting was assigned a number, plotted on a map, and the information collected was transcribed onto data forms (see Figure 1). A tally of eagle numbers and flight times were recorded on aerial survey data sheets (see Figure 2). Ground Procedures rround surveys were conducted subsequent to aerial surveys in those areas accessible by roads. Survey routes, weather conditions, waterway condition, eagle numbers, locations and activities were recorded on ground summary data forms (see Figure 3). • Consistently used perch trees and night roosts were checked periodi- cally for prey remains and castings. These were collected in plastic bags and labeled with dates and locations for future analyses. Attempts were made at the Disappointment Roost to observe the behavior of the birds during the day and also record the direction these birds flew when departing from the roost each morning in order to determine hunting areas: Behavioral activities and times were recorded on obser- vation data sheets (Figure 4). Efforts were made to estimate rabbit population numbers in high and no eagle use areas in order to determine if rabbit species are a sig- nificant component of the prey base. A 15-mile transect and 12.5-mile transect were driven along roads in Disappointment and Dry Creek Valleys which were high use areas. A 15-20 mile transect was driven through Paradox Valley, which received little or no use by eagles. Open bed trucks were driven at 10 mph while a biologist spotlighted areas on either side of the road using an IPF-802 Halogen quartz light. Species of rabbit, number of rabbits, mileage and perpendicular distance from the rabbit to the truck were recorded. Each of these transects was re- peated on three consecutive nights. Results were tallied and numbers averaged. r~