No One Saw This Coming: Endoparasitic Mites Behind the Eyes of a Double-Crested Cormorant.

Abstract

We found hundreds of mites behind the eyes of a Double-crested Cormorant, Phalacrocorax auritus (Suliformes: Phalacrocoracidae). The mites were Neottialges evansi (Acari: Hypoderatidae), representing the first report of this parasite in P. auritus from western North America. Deutonymphs of N. evansi are endoparasites, typically reported infecting fat deposits over the pectoral muscles, axillary areas, and vent of cormorants. Here mites infected only orbital tissues, a new infection site for hypoderatid mites. We suggest a lack of reports of this infection site could be explained by limited scrutiny of orbits, and deutonymphs mites infecting orbits may be more common than expected.