Jan. 5 (UPI) -- New DNA analysis suggests nomadic swift parrots from Tasmania and the surrounding islands form a single population -- a population increasingly vulnerable to extinction.
Scientists collected DNA samples from nestlings on the predator free islands of Bruny and Maria and compared the genetic code to the genome of parrots on Tasmania. The results, detailed this week in the journal Animal Conservation, show the parrots are not genetically isolated. Instead, the island and Tasmanian parrots form a single nomadic population.
"We already recognize the importance of predator-free islands as havens for swift parrots, but our findings demonstrate that protecting islands is only part of the solution to saving the parrots," Dejan Stojanovic, a researcher with the Australian National University, said in a news release.
The research suggests parrots move to where the food is, and if the food is on Tasmania, parrots will go to Tasmania, where predators await.
"This new genetic evidence shows that islands don't support a genetically distinct subpopulation of swift parrots," Stojanovic said. "Birds that nest on islands in one year may move to the Tasmanian mainland the next year, putting them at risk of being eaten by sugar gliders."
The findings highlight the importance of addressing major threats to swift parrots on Tasmania. Research has shown habitat loss and predation by sugar gliders, small nocturnal possums, are shrinking swift parrot numbers.
"Protecting islands from deforestation is a good start for the swift parrot, but this alone will not save them from extinction," Stojanovic said. "We need to better protect mature forests on mainland Tasmania to stop these birds from going extinct."