February 5th 2006
The creature few would argue is the most memorable, distinctive and iconic of Magnetic Island is surely the Bush Stone-Curlew. But, in the following article by Island resident and Zoologoist, Eric Vanderduys we learn that these are but one of three "curlews" that can be found on Magnetic. Ed.
By Eric Vanderduys
Magnetic Island is famous for its curlews. Every night most residents go to sleep with curlews' mournful cries ringing out somewhere nearby, or else don't go to sleep because their cries are under the bedroom window! Curlews are everywhere and in big numbers too. But what many residents don't realise is that there is not one, nor two, but three types of "curlew" on Magnetic Island. The birds we all call curlews (more properly, in my opinion, known as Maggie Island Garden Gnomes) are usually called Bush Stone-curlews by those who care to use "correct" names. They also go by the names Bush Curlew, Bush Thick-knee or Burhinus grallarius in scientific parlance. A swag of old onomatopoeic colloquial names like "Weeloo" exist also, all local interpretations of the curlew's call.
Bush curlew babies. Hatchlings will frequently nestle into
parents feathers for warmth and protection.
Our common Garden Gnomes have a close relative, the Beach Stone-curlew. Going by the scientific name Esacus neglectus, or the alternative common names of Beach Thick-knee or simply Beach Curlew, these curlews live mainly on quiet beaches and the dunes behind them. They usually feed on small crustaceans on mud and sand flats at low tide. While Bush Curlews are everywhere on the island, Beach Curlews are rare, and not just on the island but virtually everywhere. Currently (January 2006), there are probably no more than four Beach Curlews on Maggie.
Beach curlews. The bird on the right is last year's offspring, just noticeable by the broken white stripe behind the eye. A week after this picture was taken this youngster was unceremoniously turfed from the parents' territory to make way for a new ball of fluff. Two week old Beach curlew baby. The similarity to bush
curlews is obvious when they're young.
Both Bush and Beach Curlews breed on Magnetic Island. Most of us have at some time almost tripped over a brooding Bush Curlew which has jumped up, wings open and screamed at us at the last minute, inducing heart attacks and other unfortunate anatomical accidents. When closely examined, the spot from which the previously camouflaged bird emerged is often revealed to be a simple nest of 2 eggs (sometimes as many as 4). Beach Curlews lay only one egg (rarely 2) and it's a big one. The nest is usually at the head of the beach, or in dunes behind the beach, and like the Bush Curlew's nest, is little more than a scrape on the ground.
Budding birdos, Deb Jeacle and Daina Clark,
watching an adult Beach Curlew
Breeding locally is one of the features that sets these two curlews apart from the third Magnetic Island curlew. This is the Eastern Curlew and it breeds in Siberia! Its scientific name, Numenius madagascariensis, is almost as long as the flight it makes to get there. Confusingly, Eastern Curlews are also sometimes called Beach Curlews, because they inhabit beaches and mud flats. Eastern Curlews are only distantly related to Bush and Beach Curlews, but have the same name because their calls are somewhat similar. Other than that, the similarity ends with the name. Why would a bird want to breed in Siberia and then fly to Eastern Australia for the rest of the year? Well, loving this part of the world I can see why they'd want to be here - highly productive mudflats provide a rich source of food for many millions of birds - so perhaps the question is "Why fly to Siberia?" a many thousand km round trip? The answer is that the Arctic Summer (our Winter) provides vast quantities of shallow freshwater over frozen soil, with virtually 24 hour sunlight, that forms a very productive food chain. Eastern Curlews, and many other migrants, exploit this productivity to support their breeding cycle.
Eastern Curlews occur around most of the Australian coastline. Here on Magnetic Island some are present all year round, although their numbers are usually low during our Winter when many of the adults have flown north to breed. Those that remain behind probably don't make the flight because they have insufficient condition for the long journey.
Eastern Curlew. The extremely long curved beak is a good way to tell this species from similar looking birds on the island.
During low tide Eastern Curlews use their very long, curved bill to probe mud and soft sand for small invertebrates like worms and crabs. At high tide, they move to saltpans and other open areas where they roost above the high water. For this reason, Eastern Curlews need two types of habitat in order to survive, one within the tidal zone, and one above it. Both are present on Magnetic Island, especially along the southwest.
Beach Curlews are the rarest of the curlews on the island, and are listed as "Vulnerable" under Qld legislation. Eastern Curlews are listed as "Rare" while Bush Curlews are listed as "Common". Bush Curlews have suffered drastic declines in most southern parts of Australia but they are still common in open woodlands over much of the north of the continent including most of eastern and northern Queensland. Eastern Curlews receive special recognition because of their long migration