Avian trichomonosis, caused by the protozoan Trichomonas gallinae, is an infectious disease affecting birds worldwide, and is usually fatal in nestling golden eagles.
Degraded habitats may cause golden eagles to switch from foraging on native prey to rock pigeons, which commonly carry T. gallinae. In 2015, researchers found evidence of T. gallinae infection in golden eagle nestlings in five western North American study sites, with a relatively high infection rate in southwestern Idaho. The proportion of rock pigeons in eagle diets in southwestern Idaho was higher in recent (2014-2015) versus historical periods (1971-1981), as was the proportion of eagle nestlings with trichomonosis lesions. Nestlings with diets that consisted of greater than 10 percent rock pigeons had a very high probability of T. gallinae infection. Results suggest that shifts in eagle diet from habitat degradation and loss of historical prey have the potential to affect golden eagle nestling survival. Findings support the hypothesis that land use change can alter biological communities in a way that might have consequences for disease infection and host susceptibility.
Dudek, B.M., Kochert, M.N., Barnes, J., Bloom, P.H., Papp, J., Gerhold, R., Purple, K.E., Jacobson, K.V., Preston, C.R., Vennum, C.R., Watson, J.W., Heath, J.A., 2018, Prevalence and risk factors of Trichomonas gallinae and trichomonosis in golden eagle (Aquila chrysaetos) nestlings in western North America: Journal of Wildlife Diseases, v. 54, no. 4, https://doi.org/10.7589/2017-11-271.