Hyla avivoca (Viosca, 1928)
Description
Bird-voiced tree frogs are found throughout Mississippi. This species was first described using a type specimen from St. Tammany Parish, Louisiana in 1928 (Smith, 1966). They’re medium-sized tree frogs (~ 38mm snout-vent length in males and ~ 53mm in females) that are usually gray or green “lichen” colored with a greenish light marking below the eye. Thighs are mottled with small green spots or blotches. The male’s call is clear and recognizable in late spring and early summer. For those new to the interest of frog calls, it could be mistaken for the tweeting of a bird, a clear “weep” “weep” “weep” “weep” in succession. Listen to recording below for reference. While the calls are quite different between H. avivoca and H. chrysoscelis, hybrids between the two species were noted in Alabama with mixes in coloration and call frequencies (Mecham, 1960). Hybridization between Hylid treefrogs may happen on occasion in busy breeding wetlands.
Identifying Traits
- Green or gray “lichen”-colored body, often smoother looking than Cope’s gray tree frog.
- Green spot below eye
- Green spots on inner thigh (see photo; separates from other tree frogs)

Habitat
Wooded swamps often around flowing water (Peterson et al., 2016)
Behavior
Male call sounds almost like a bird. Clear “weep” “weep” “weep” “weep” in quick succession. Uniquely among North American treefrogs, H. avivoca males will alternate, or interdigitate, their call pulse between other males’ as to reduce overlap in the acoustic space and increase the likelihood of a female responding (MartÃnez-Rivera and Gerhardt 2008).
Diet
Various invertebrates