I really like having a ready reference online, in addition to my field guides.
The eNature site is my latest reliable site for identification. It lets me narrow the field by zip code if I want to narrow my search. In addition to the Patuxent site for bird identification, this eNature site is now bookmarked for my ready reference.
The pickerel frog had motivated my search. eNature, like Patuxent, offers photos, descriptions and sometimes audio. I’ll always love my books, but I really love the added info in these files.