ON THE WING
WITH DON KNOWLER
The weather forecast predicted a dull, overcast day for the annual Tasmanian gull count this year, an apt metaphor for birds that always seem to be under a cloud.
Lots of people do not like gulls, particularly silver gulls which hang around the fish punts on the waterfront, always seizing a chance to steal a chip or two.
The gulls are called “rats with wings” in some quarters and I always think this is an unfair appellation for them.
Amid the squawk and squeal, the mess, the gull frenzy on the docks and at the nearby fast-food outlets, most of us never take the time to study the gulls in detail and to appreciate their beauty.
I confess, I don’t usually give gulls a second glance when birdwatching, unless one day a year I am charged with counting them as part of the BirdLife Tasmania annual survey. The count is important to establish gull populations are in a healthy state, and there is also a spin-off for humans. Because two of our three gull species, silver and kelp gulls, live in such proximity to humans they also act as barometers of the health of the urban environment. Anything that impacts on gull populations – like poisons – might ultimately affect us.
Gulls in the urban landscape are prone to the same ills that afflict humans who gorge on fast food. City gulls compared with those on Bass Strait islands have more cholesterol and are overweight.
Similar gull counts in the UK have also confirmed the importance of such an exercise. Populations of the European herring gull have plunged by about 50 per cent since the 1970s and although avian botulism, a bacteria picked up from warm contaminated water, is partly to blame, conservationists mainly ascribe the drop in number to the decline of British fish stocks because of over-fishing.
The gull count is my least favourite birding activity. It’s really hard trying to get to grips with hundreds of birds as they wheel about you at their favourite haunts, like rubbish tips. The kelp gulls and the third Tasmanian species, the Pacific, also have to be separated into first-year and older juveniles to establish how successful the latest breeding season has been. (Firstyear birds are all brown, and older ones have “salt-and-pepper” mottled plumage before reaching maturity in four years.)
Last year I was assigned the Glenorchy tip and surrounding areas and for the latest count I had an easier ride – the eastern shore of the Derwent. No rubbish tips, or fast-food outlets. And I had misread the weather forecast, the day turning out to be sunny. In the bays along the Derwent shore from Lindisfarne to Bridgewater I found gulls purged of all human association. Far from resembling rats with wings, the gulls flew on delicate silver wings, balancing the powers of wind and gravity, moving, darting, then hanging above the sparkling blue waters in a blaze of reflected light.