Some Observations on Hochstetter's Frog in the Catchment of the Motu River, East Cape

The distribution and abundance of Hochstetter's frog (Leiopelma hochstetteri Fitzinger) in part of the catchment of the Motu River was assessed during two short surveys in 1981 and 1983. Specimens were found in most tributaries examined and on the banks of the main river, above extreme flood level. Crude indices of abundance were obtained by relating the numbers found to the time spent searching and number of stones and logs turned. Generally about four frogs were found per hour, but there was considerable variation in counts obtained in simultaneous searches by different observers. The highest counts were obtained in areas with stable, moss-covered substrates, shaded by overhanging vegetation. Frogs in the upper Motu River were significantly further away from the edge of streams than those in the catchment of the Takaputahi River. Most adults were dark grey or dull khaki, spotted with rust or brown, whereas juveniles less than 20mm long were bright lime green. Snout to vent lengths ranged from 15-46 mm and weights from 1.0-7.1 g. A cluster of eggs with well developed embryos was found in the catchment in March 1983.