Volunteers said that after an early rush of visitors, the mercury rose, numbers dried up and the island became ``unbelievably hot''.

Layla Anderson, 8, of Launceston,  went along early with grandfather Alan Anderson.

``I probably liked the walkway through the long grasses best and we saw a baby lizard,'' she said.

``We saw a scrub wallaby with red eyes and went to the snakes and the bird hive - we were going to go to the island, but it got too hot.''

Mr Anderson said that with Layla going back to school, the visit would stand her in good stead for nature studies.

``A visit to the wetlands is good for kids' education as well as adults,'' he said.

Tamar Island Wetlands volunteer John Duggin said that International Wetlands Day celebrated the 1971 signing in Iran of the Ramsar Convention.

``Australia was one of the early signatories to the convention and Tasmanian became the first state to nominate 10 wetlands,'' he said.

``The Tamar Island area is not one of them, but it's a great place to illustrate the importance of wetlands and their wise use.''