Field studies on the small Surinam toad, Pipa arrabali, near Manaus, Brazil

Abstract

AbstractA population of the small Surinam toad, Pipa arrabali, was studied at an isolated pool site in undisturbed primary forest, 70 km north of Manaus, Brazil. During the eleven months of examination, 371 individuals were toe-clipped. The toads preferred more persistent pools where they preyed upon tadpoles of other anurans. If a home pool dried up or a source of food became available in one of the other pools the toads migrated over land for short distances. Of a total of 84 recaptures, 28 (33%) were found in a pool other than the original. P. arrabali bred throughout the entire year, but females with larvae in the dermal pockets on their backs were particularly frequent at the end of the rainy season (April to June). No free swimming larval stage occurs. Depending on the size of the female, between 6 and 16 eggs develop directly into small toads. Snout-vent length at emergence ranges from 10 to 14 mm.