Courtship, Reproductive Rates, and Mating System in Three Australian Pseudophryne (Amphibia, Anura, Leptodactylidae)

Abstract

Pseudophryne bibroni, P. dendyi, and P. semimarmorata males prepare nest sites on land in situations which subsequently become flooded by a progressive rise in the groundwater table associated with autumn rainstorms which occur at intervals of about one week. Courtship behavior, reproductive rates and mating systems are very similar in these three species. Gravid females had 16-190 enlarged ova when collected; mean values for each species are in the range 103-140 ova. Seventy-eight nests contained 8-677 eggs; 52-71% of the nests of these species contained embryos produced at a single mating-typically 73-98 ova (range: 8-194 ova). The remaining nests contain two or more batches of eggs of different ages. Apparently less than half the females lay all their eggs at once (monobrachyandry). Most appear to lay decreasing numbers of eggs on 2-3 successive nights at a single nest (seasonal monogamy) or else they mate on several occasions during the 4-7 week breeding season (successive polygamy). The female's habit of staggering her egg laying may be an adaptation to irregularities in the cyclical pattern of rainfall during the breeding season in southeastern Australia. * * *