The Environment team commenced annual frog monitoring last night where tadpoles and frogs are counted every fortnight from autumn to spring as part of the Island’s conservation action plan. The monitoring is used as a measure of the island’s water quality, as frogs are particularly sensitive to changes in their environment. The freshwater seeps and brackish swamps provide critical breeding sites and habitat for the island’s frog species, and by counting the tadpoles and noting the frogs we get a good indication of the health of the wetland.
Rottnest supports three frog species — the Moaning Frog (Heleioporus eyrei or Burrowing), the Squelching Froglet (Crinia insignifera) and the Motorbike Frog (Litoria moorei or Western Green Tree frog). The Moaning frogs are usually the first to emerge after the first decent Autumn rains, followed by the Sandplain froglet over Winter, and the Motorbike frog in Spring.
After the heavy rains experienced over the last week, the Moaning frogs have emerged from their burrows, and last night they could be heard chorusing in force. One site was already swimming with tadpoles!
In addition a lone (and obviously keen) Sandplain froglet was heard, and several of Motorbike frogs were observed hanging out near one of their favourite spots.
All in all a promising start to the season.
Find out more about the Island's Wetland habitat.