September 5, 2001
Waitakere residents are again being asked to listen out for frogs ‘bonking’ in the night.
The Auckland Regional Council is about to restart monitoring for Australian eastern banjo frogs, also known as ‘bonking
frogs’ in the Waitakere Ranges near Mt Donald McLean.
It’s the banjo frog’s call - a short musical, explosive note producing the resonant ‘bonk’, similar to the noise
produced by plucking the string of a banjo, which gives the frog its nickname. The call is usually repeated every few
seconds and individuals can produce a rapid series ‘bonk bonk bonk bonk’ lasting about one second.
An import from Australia, the Banjo frog is extremely aggressive and would eat a large variety of our native insects,
small frogs and skinks. It carries chytrid fungus - a major cause of global frog declines - which puts New Zealand’s
rare Hochstetter’s frog at risk.
The adult Banjo frog is medium sized (70mm) with a warty skin. In spring it lays frothy egg masses (about 10cm in
diameter) on still water. About 1000 small tadpoles with leopard-like stripes and spots on their tales hatch out within
a week.
There is still a possibility that the frogs are in the Huia and Whatipu area. A frog call monitoring device has been set
up between Little Huia and Whatipu. It delivers a frog call every minute and records sounds for nine seconds after each
call to check for responding frogs. The frog calls are made for the first three hours after darkness.
Anyone who sees or hears anything they think might be a banjo frog should call the ARC on 366-2070. The frogs are
especially vocal on warm nights after 2-3 days of heavy rain.
Last year monitoring was done in several areas over the warmer months between August and February when the frogs are
most active. However no frogs or tadpoles were found.
Ends