Adult and Juvenile Frogs of Whatcom County – A Picture Guide Whatcom County Amphibian Monitoring Project (Photos © Stephen Nyman) Northern red-legged frog (Rana aurora) • Common species • Usually brown or tan, with dark eye mask • White lip line • Prominent dorsolateral folds • Adults usually reddish under hind legs • Colorful groin mottling • Juveniles may be yellow, honey-colored or pink under hind legs • Eyes outward facing • Relatively smooth skin • Usually responds to approach by leaping away • May be seen in forested areas far from water Pacific chorus frog (Pseudacris regilla) • Very common species • Small and delicate appearance • Color variable (green or brown) • Dark eye mask • Often with irregular blotches on back • Toe tips enlarged • Our most often heard native frog • May be heard far from water Western toad (Anaxyrus boreas) • Dry, “warty” skin • Large gland behind each eye • Light colored mid-dorsal stripe (not present in small juveniles) • Walks or makes small hops • Often observed far from water • May be a declining species – report your observations! American bullfrog (Lithobates catesbeianus) • Introduced species • Aquatic, usually at permanent water-bodies • Large! • Usually brown and/or green • May have dark blotches • Dorsolateral fold short, bending partly around eardrum • Breeding call a deep “jug-a-rum” or “br-wum” • Juveniles often heard (“eeep!” – followed by a splash) juvenile juveniles juvenile juvenile