By Molly Bilker / Photo by Bruce D. Taubert
As tadpoles are to toads, water dogs are to tiger salamanders: the fully aquatic larval form of the species. When water dogs metamorphose into adult salamanders, some lose their fringed, external gills and grow lungs, allowing them to leave the water. Others, known as branchiate adults, remain aquatic. These salamanders breed in larval form, and the sexually mature larvae can be distinguished by coloring — the immature are usually dark green.