Far off-shore a gannet wheeled in the sky across the Derwent Estuary. It paused as if frozen in mid-air and then plunged into the water, sending up a huge spray of water. It emerged with what looked like silvery fish before the seabird was beating the air again with huge black-tipped white wings.
I was watching a remarkable bird at a remarkable place, Crayfish Point at Taroona, a birdwatching hotspot that had escaped my attention in the past.
I have to thank our gardening writer Tino Carnevale for pointing me in the right direction. In an item on ABC’s Gardening Australia last month he mentioned Taroona’s Foreshore Walk in a wider story about students at Taroona High School applying citizen science to the study of nature and the environment.
Tino had packed away the spade he usually uses in the Royal Tasmanian Botanic Gardens to see how the students were “making a difference” in their environmental studies.
As Tino described it, Taroona High is home to Tasmania’s first climate watch trail where students can track data related to a warming planet.
The trail covers a diverse range of habitats along the Taroona foreshore and nearby bush, and daily trips are made to look for signs of seasonal changes – new flowers or buds, fruiting, animal species – which are then logged and uploaded to a central data base.
Student leader Mackenna Minstrell explained that these small, localised observations could then be fed into a national and then global set of data and used to detect any big-picture changes in the environment.
The students said they believed climate change was affecting temperature and rainfall, and their project would help map how local flora and fauna were responding. They would also follow in the footsteps of the first Australians to tread this coastline, the Mouhenneener Aboriginal people. “Taroona” is in fact the Aboriginal name for chiton (kytun) – a shell animal found along the foreshore.
The route meanders for about two kilometres, from the high school grounds, to Crayfish Point, and then on to Taroona and Hinsby beaches, with a backdrop of the Alum Cliffs to the south. The remnant coastal bushland includes a canopy formed by blue and black gums, sheoaks and blackwoods, with an understorey of hopbush, banksias, coast wattle, salt bush and grasses.
As always, my interest was in the birds found along the coastline, and out to sea. Tasmanian endemic species like yellow-throated honeyeaters and yellow wattlebirds sang from the trees above my head and perched on rocks just offshore at Crayfish Point, little pied and black cormorants dried their wings in the warm autumnal sunshine.
Storm clouds were gathering, though, and as I turned for home I gazed across the Derwent for one last look at the gannets. A rainbow had spread across the estuary from east to west, and three gannets were framed by its arc.