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Bryan L. Sharp

Publications and source records attributed to Bryan L. Sharp.

2 recordsLinked to original sources

Puncture-ejection of own egg by Least Bell's Vireo and potential implications for anti-parasitism defense

A simple, papillary cystic adenocarcinoma of the mammary gland with metastases to the internal iliac and mesenteric lymph nodes, liver, and spleen was observed in a 12 to 13 year old female black-footed ferret (Mustela nigripes). Histologically, the tumor was aggressive, and lymphatic invasion was found. Attempts at virus isolation were negative. Other findings were bilateral infarcts in the kidneys, apparently resulting in acute renal shutdown and death, multiple thrombi in the right atrium, aortic arteriosclerosis, and focal interstitial pneumonia.

Western Birds↗

Sunrise nest attendance and aggression by least Bell's vireos fail to deter cowbird parasitism

We video-recorded three, natural, brood-parasitism events by Brown-headed Cowbirds ( Molothrus ater ) at nests of Least Bell's Vireos ( Vireo bellii pusillus ). All instances occurred near dawn, during both egg-laying and incubation stages of the nesting cycle. In each case, an adult vireo was on the nest when the female cowbird arrived. Both members of each parasitized pair vigorously attacked the intruding cowbird, but in no encounter did a pair of vireos successfully defend its nest from parasitism. Thus, Least Bell's Vireos in our study were unable to prevent a female cowbird from parasitizing their nests once the cowbird had reached the nest.

The Wilson Bulletin↗