Eating habits of Silver Gull [Chroicocephalus novaehollandiae]
“Gulls are scavengers and do not dive into the water but pluck offal from the surface or from land” [Newman’s Birds of Southern Africa 7th Ed] “Some native predators/scavengers such as Silver Gull……are at artificially high densities, as human wastes provide rich and abundant food allowing populations to become superabundant” [Shorebirds of Australia A Geering et al 2008] A quick review of common gulls in the National Audubon Society “Field Guide to North America” reveals that some gulls frequently gather around garbage dumps, sewage outlets, and reservoirs where they are attracted to a variety of scraps and refuse including, in some cases, animal droppings and berries. Birdlife Australia’s introduction to their monograph on the Silver Gull states “There weren’t always as many Silver Gulls as there are now. Since the 1950s society has become increasingly wasteful, with our rubbish tips now bulging at the seams. With this increased availability of food in the form of refuse, the population of Silver Gulls has exploded, and offshore islands which once supported small breeding colonies are now over-run. With so many gulls dominating these breeding islands, it is becoming increasingly difficult for terns and other seabirds to breed there.” This all seems to paint a fairly miserable picture of the bird that many of us will have happily associated with beach visits most of our lives. None of these descriptions seemed particularly attractive for a bird that I have always thought of as, in appearance at least, clean, beach loving, fishing, sociable and pretty. To try and present a more pleasant view of the Silver Gull, a couple of encounters Margie and I have had with them at Black Point may help to improve their image. On a more serious note and despite the varied diet of these birds the average life span of the Silver Gull is around 23 years, with the oldest recorded 28 y 8m. They begin breeding at the end of their third year for about 11 years - but may breed more than once per year. Back in December 2008 at Black Point, Margie noticed a visiting Silver Gull to The Shack was wearing a band. As the gull observed the lunch table Margie was able to get good photographs of all of the details on the band [photos below] and submit this information to the Australian Government Department of the Environment, Water and Heritage and the Arts Bird and Bat Banding Scheme. They replied that the band had been placed on a Silver Gull on 6/11/1993 at the Breakwater, Outer Harbour SA and that the bird was age code First Year, sex unknown and gave the name of the bander. That was about 15 years between banding and the sighting at Black Point about 56km away
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