Annual Reproduction and Clutch Size in Rain Forest Frogs from Sarawak

Abstract

Six Bornean species of rain forest frogs-Bufo asper, Rana blythi, R. ibanorum, R. macrodon, R. hosei, and Amolops jerboa-apparently breed throughout the year. There was no evidence of seasonal trends in spermatocyte counts, egg size, or proportion of ripe females, in spite of variations from month to month. The clutch sizes of the four species of Rana are smaller than those of temperate zone species of comparable size, whereas B. asper does not differ from related temperate species in this regard. Comparison of A. jerboa with temperate species in terms of egg counts is uncertain.