Food habits and reproductive biology of small Australian snakes of the genera Unechis and Suta (Elapidae)

Dissection of 1607 snakes provided data on natural history of nine species of small (<50 cm snout-vent length), widely-distributed Australian elapids. Males and females matured at similar sizes, with males tending to attain slightly larger maximum sizes. All species examined are viviparous, and show similar litter sizes (means of 3 to 9 offspring) and offspring sizes (10 to 18 cm SVL). Fecundity and offspring size were highly correlated with mean maternal SVL in an interspecific comparison. Ovarian follicles of adult females undergo vitellogenesis in spring, with ovulation later in spring and parturition in summer. Museum collections of all species contain approximately equal numbers of adult males and females, as is generally true of small, cryptic elapids. However, the proportion of adult females which were gravid (<3% of adult females) was surprisingly low. 

All eight species of Unechis feed mainly on scincid lizards (83% to 100% of all prey items recorded), whereas the single species of Suta studied consumes a broad range of skinks (37% of prey items), geckos (17%), agamids (17%) and mammals (20%). The overwhelming importance of scincid lizards in the diet of Unechis is similar to the situation in most other small Australian venomous snakes.