Fossil remains of the now extinct giant Maltese swan have, for the first time, been discovered outside Malta in nearby Sicily.

The remains were found in a lacustrine (lake-associated) deposit in the suburbs of Syracuse, in south-eastern Sicily, by Marco Pavia, from the University of Turin, who described the findings in a paper recently.

Apart from bird bones, bones of mammals that also inhabited Malta in Pleistocene times, some 125,000 years ago, were found in the same site. These included species such as the Maltese dwarf elephant and small species of hippo, the Maltese vulture (Gyps melitensis) and Maltese crane (Grus melitensis). All these species are extinct.

At that time, Malta was linked to Sicily by land bridges that enabled the species to cross to and fro but when the land bridges became submerged under water, local populations got cut off and developed into species with their own characteristics.

George Zammit Maempel, Malta's leading palaeontologist, who studied the faunal remains from Ghar Dalam and other areas, had concluded it was probable that the land bridges were never terra ferma and animals had to wade or swim parts of the way as no remains of non-swimming animals have ever been found in Malta.

Large mammals migrating southward to escape inclement climatic conditions prevailing in central and southern Europe could reach Malta through these new pathways. This, of course, did not apply to migratory birds that could fly.

Dr Zammit Maempel had noted in his writings that dwarfing or stunting of large mammals was a characteristic feature of Mediterranean islands such as Malta, Sicily, Crete and Cyprus. This was an adaptive evolutionary process to ensure survival of the species.

The remains in Sicily were found with hundreds of other bird remains that are still being studied. But preliminary results that have been published have already identified 51 species or families of birds. These include grebes, herons, bitterns, ibis, geese and ducks, buzzards, vultures, hawks, quail, cranes, bustards, woodcock, doves, owls, robin, thrushes, warblers, starlings and crows.

A number of species that were identified were common to both Malta and Sicily. The Maltese vulture and Maltese crane, found in several Maltese sites, had been found in other localities in Sicily but the giant Maltese swan had hitherto been unrecorded.

E. Marjorie Northcote, from the University of Cambridge, who studied the remains of the giant Maltese swan, had concluded that the bird was widespread in Malta as remains had been found in several deposits around the island. These remains are stored at the Natural History Museum at Mdina, the British Museum of Natural History and the University Museum of Zoology in Cambridge.

Dr Northcote had established that the swans weighed some 17 kgs and had a wingspan of three metres but were still flightless because the biggest birds that can fly do not weigh more than 14 kilogrammes. A bone forming part of a skull that was found to have housed the salt gland, the size of which is related to the amount of salt secreted, showed the gland of the giant Maltese swan was very small, leading one to conclude that the swans were more terrestrial and fed inland, away from salty water.

As there were no large predators in Malta at that time, and there was a lush flora, flight was unnecessary for feeding, mating and escaping.

Dr Northcote argued that the giant Maltese swan evolved from the Eurasian swan when it adapted itself to exploit the inland fauna existing in Malta at the time.

As inland grazers, these large swans occupied a specialised niche and the rapid changes brought about by the interglacial period brought rapid environmental changes which the swans were unable to survive.

The giant Maltese crane was much smaller, weighing around eight kilogrammes. It too was widespread as remains were found from a number of deposits. Bones of cranes were often found with those of swans.

Fifty-five species of birds or bird families have been identified from fossils by various authors in Malta. These include species that have not been recorded in recent times, such as the Bonelli's eagle, the willow grouse and both brent and barnacle goose.

But the remains include several species that are still seen today, such as quail, thrush, pintail, mallard, scops owl and marsh harrier.

Studies on bones that had previously been identified as belonging to certain species are often carried out with new techniques and this sometimes leads to corrections.

A typical example is the study by Storrs Olson, an osteologist and palaeontologist, who looked at remains that had previously been classified as belonging to an extinct species of woodcock (Scolopax ghardalamensis) but he has now determined the bones belonged to quail, which was migratory at that time too.

John J. Borg, the collections and site executive of the Natural History Museum in Mdina, recently found remains of cory's and yelkouan shearwaters from caves.