Multiennial reproduction in females of a viviparous, temperate-zone skink, Tiliqua nigrolutea

We examined the reproductive frequency in wild-caught and captive females of Tiliqua nigrolutea over five consecutive reproductive seasons. Reproductive frequency (0.38 ± SE 0.035) was clearly different from an annual pattern (1.0) in which all females reproduce every year. Individual females did not reproduce every year, but "skipped" seasons were staggered such that a proportion of the population produced a clutch each season. We attribute skipped reproductive opportunities to a combination of a long gestation, high relative clutch mass (0.43 ± SE 0.034), parturition late in the active season, a cessation of feeding in the latter stages of gestation, and low autumn temperatures that limited post-partum feeding opportunities.