THE hot-chip brigade – the gulls that try to steal our fast food on the waterfront – might be viewed as a nuisance but they are a vital indicator of the heath of the human environment.
They are certainly not “rats with wings”, to use a pejorative description used by some members of the community who are not gull fans.
Such is the regard that birders give gulls that a dedicated team of Birdlife Tasmania members each year conducts a survey of gull numbers far and wide to determine if there are any issues concerning the family members – like the effects of pollution – we should be concerned about.
There are three species of gull in Tasmania – the kelp, pacific and silver gull – and the latest survey was designed to confirm that gull populations are holding their own.
Gulls, perhaps more than any other group of birds, are at the interface of the animal and human world and experience has shown that what affects gull numbers is likely down the track to affect humans.
Birds in general are highly susceptible to poison of all kinds and possibly the strongest barometer for environmental health, after fish.
As the co-ordinator of Birdlife Tasmania, Eric Woehler, puts if: birds are modern canaries in the coalmine. He is referring of course to the canaries that used to be taken down coalmines to test for methane gas. If the canary passed out, the miners knew there was deadly methane in the atmosphere that could not be detected by smell.
Remarkably, besides possible pollution, the gulls of Hobart have health issues that mirror those of the humans that frequent not only the fish punts on the docks but the fast-food hamburger, fried chicken and pizza joints in town.
Research comparing Hobart silver gulls with those on the Bass Strait islands reveals that the gulls here suffer from dangerously high levels of cholesterol, and are overweight.
The gull situation is exacerbated by them not only stealing chips on the waterfront, but feeding on the Hobart and Glenorchy rubbish tips.
For the second year running I joined the gull survey, counting numbers along each side of the Derwent from the Tasman to the Bridgewater bridges.
Before I started birds Birdlife Tasmania sent me an official checklist in which I not only had to record the three species but the exact location where they were found. There were also tips on identification but this is not too difficult, compared with shorebirds which are also counted in another exercise. The wader count takes place twice a year to record both summer visitors and those choosing to over-winter in Tasmania.
The gulls are easy to separate by size and by the shape of their bills. The largest are the kelp and pacific gulls, the latter having a flattish bill shaped more like a pair of pliers. This has a large orange tip whereas in the kelp gull’s bill is largely yellow in colour.
The silver gulls are considerably smaller with red bills and legs, and white eyes.
My day started with kelp gulls frolicking in the shallow waters of Cornelian Bay in New Town and ended with silver gulls under the Tasman Bridge in Lindisfarne.In between times, I received some menacing stares from a group of young men in one of the rougher areas of the metropolitan area bordering the Derwent and known for its drug trade.
Binoculars, notebook and the police-blue Land Rover Discovery I was driving indicated I might have a different intent. And for once, the gulls took a backseat as, after recording a brace of the kelp species, I hit the road in a hurry.