Adult Bald Eagle (Haliaeetus leucocephalus) call and fly off Prosser Reservoir, Nevada County, CA
Calls of an adult bald eagle perching on a snag overlooking Prosser Reservoir (~5,700 feet) on the eastern side of the Sierra Nevada in Nevada County, CA. This was recorded on the morning of November 12, 2008. On the previous day friends and I visited the area looking to add to the Big Year Count. At this site there were 3 adult and one immature bald eagle at one time. An attempt to record calls was marred by both traffic noise from Interstate 80 and off-road motorcycles in the area. I returned this morning about 0730 when a thin fog blanketed the area. By 0900 it had burned off and around 1000 an adult bald eagle flew into the snag.
The eagle had two series of calls about 45 minutes apart, and departed to the West shortly after the last vocalization. For the sake of brevity both calls appear one after the other in the audio file. At the end the wingbeats, 3-4 per second, can be heard. The beats are also accompanied by a whistling sound as the primaries cut through the air. For the last bit headphones will help. Traffic noise from I-80, 2 miles away, can still be heard in the background.
SD-722 Telinga dish, and twin science microphone