02-12-14 Raptor Field Note

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02-12-14 Raptor Field Note

February 12, 2014

Raptor View Research shares the difficulties faced by a male golden eagle with debilitating injuries to it's tounge and left foot.

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On 22 January 2014 we captured an adult male golden eagle at our northern bait station on the MPG Ranch. When we approached the eagle, we immediately noticed gross deformities on its left foot. Closer inspection revealed a fracture at the ankle. The nature of the injuries suggest that the bird got caught in and escaped from a leg-hold trap some time ago.

The tip of the eagle’s tongue showed signs of severe damage from past trauma, potentially frostbite. The bird’s beak closed properly but with compromised function, apparently due to the tongue injury. Because the tongue plays a crucial role in the preening of feathers, this eagle could not properly clean itself and was covered in lice and their eggs.

In addition to the severe feather lice infestation, we also discovered fault bars in several wing feathers. Fault bars develop on growing feathers in times of nutritional deprivation and usually indicate that the bird endured a major stress.

The lead level in the eagle’s blood exceeded 65 μg/dl, the maximum reading that our field testing unit displays. None of the 38 eagles previously sampled on the MPG Ranch tested above 40 μg/dl (mean 20.3, median 20.6 ). An elevated lead level indicates that the eagle ingested lead within the past two weeks. The most likely source of lead for fall/winter scavengers like eagles is fragmented lead-core ammunition found in gut-piles left behind by hunters. The poor condition of this eagle likely limits its ability to take live prey, leaving scavenging as its primary feeding strategy.

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