Many years ago when I was a member of the bird-watching fraternity in New York’s Central Park the prospect of a “wave day” – which saw the arrival of unusually high numbers of migrating birds – got the telephone wires buzzing in pre-mobile days.
Central Park is on the Eastern American Flyway and when winds blew from the south during the spring migration birders grew excited. Millions of birds travelling from as far south as Brazil would be on the move, making their way along the eastern seaboard to Canada in the far north. With favourable weather at the height of migration time – usually in the last weeks of May – it was possible to spot 100 species in Central Park, which is about half the number commonly seen in Tasmania.
These days, living in a city which clearly does not have the same volume of migrants found in North America, my birding ambitions are a little more constrained but it is still possible to witness a wave day in the Hobart area, even if it is on a smaller scale.
Such a day occurred earlier this month when our own migration of birds heading towards Bass Strait and the mainland was underway.
After an Indian summer with temperatures touching 30 degrees, a sudden cold snap bit which told the migrants – mainly insect-eaters – that it was time to move to warmer climes. A bright sunny day, with south-westerly winds to help carry the birds north, indicated it could be a good day for birding.
I walked the Pipeline Track from the Waterworks Valley to below Fern Tree, stopping at a location which overlooks the upper Sandy Bay Rivulet. This is always a good place for a range of birds inhabiting the stream-bank, the understorey and the upper canopy of the eucalypt forests on the south-eastern slopes of kunanyi/Mt Wellington.
The gully holding the rivulet proved to be alive with grey fantails, hawking insects spiralling above the riparian vegetation hugging the stream-bank. About 20 fantails flitted about my head, either flying to overhanging perches of dogwood and silver wattle to crunch their winged food, or descending in feathery spirals of their own to land on rocks in the rivulet, to sip its cool waters.
I hadn’t seen that many fantails all summer and it was good to see such great numbers, young birds among them.
Not all fantails migrate to the mainland – about half the population stays to brave the Tasmanian winter – but it was clear that the birds I was watching were on the move. During the course of the morning they slowly flew north along the rivulet, following it into the Waterworks Valley.
It was not only fantails on the move. Big flocks of silvereyes could also be seen, picking at the last of the fruits of the native cherries.
And amid the exited twitter of the silvereyes, I could also hear the “pick-it-up” notes of the striated pardalotes higher up in the peppermint gums. The pardalotes were seeking insects in the canopy to fuel muscles for an arduous migratory journey, which takes these tiny birds as far north as southern Queensland. It would be the last pardalote song I’d hear until the coming of spring.