It wasn’t the promise of lemonade scones and the chance to catch up with my birding mate, Denis Abbott, that lured me to the panoramic setting of the restaurant at the Mt Nelson Signal Station. It was the prospect of seeing the first arrival of spring – a striated pardalote.
According to my records, the straited pardalote is always the first bird to arrive, beating the official harbinger of spring, the welcome swallow, by two weeks on some occasions.
Although it has been known for single pardalotes to remain in Tasmania during winter, the Mt Nelson bird appeared to be a new arrival in the first week of August because the species had not been seen there since autumn. It followed another report of a pardalote singing in Cambridge two weeks earlier.
The seasonal movements of migratory birds are under scrutiny as never before because of a changing climate which is bringing warmer winters. This July has been the warmest on record and it raises the question – so far unanswered – of whether it is having an impact on our bird populations, both migratory and resident.
The lives of all lifeforms are highly synchronised, obeying time scales that have been in place for millennia, if not millions of years. Birds, for instance, arriving early in unseasonal weather might find their food sources of pollen, nectar and insects are out of sequence. The rate at which trees, shrubs and flowers are pollinated could also come into play.
We are still at the early stage of research into the effects of climate change on Tasmania’s flora and fauna, but already much research has been carried out in Europe and North America.
The blue tit of Europe, for instance, has been the subject of studies into the effects of both warmer weather and the impact of urbanisation on woodland habitat.
I have a special interest in the blue tit because this colourful, tiny bird inspired my interest in birds as a schoolboy growing up in Britain.
But I have read of the concerns that, with the advance of warmer springs, the tits might not be able to synchronise the peak period of the breeding season with the availability of the caterpillars they feed their young.
An analysis of 45 years of data on blue tit behaviour has revealed, however, that some populations have shown a remarkable resilience, with adaptations to cope with higher temperatures passed to successive generations. But there is a downside – chicks starved during the 2019 European heatwave because their parents were unable to forage for insects in 45 degrees.
Back at Mt Nelson, I soon found not one but two pardalotes taking advantage of a warm, sunny day more like mid-September than early August. But I didn’t need to make the trip – when I returned home, a striated pardalote was singing in my garden.