bald eagle sitting on deadwood over pond showing nicitating membrane over eye

vestigial vertebrates translucent third surface steel sitting sight semitransparent raptor protection pond nictitating nictitan nicitating moisten membrane lubricate leucocephalus haliaeetus eyelid eye eagle deadwood bald animal perched avian ornithology steeleye thirdeye hunting drydenlake tompkins dryden tc3 rt38 virgilcreek wetlands avian ornithology birding raptor flx fingerlakes newyorkstate nys biology nature habitat