Squids in MarkCarwardineExtreme NatureOctober 2005Collins0 00 7207689

turn of the last century. Although in both previous cases devil numbers rapidly recovered, this is the first population crash since the introduction of foxes to Tasmania, and the concern is that the foxes will occupy the devil's niche and make a recovery much harder. This, of course, has serious implications for other native species. Tasmanian devils are mainly scavengers and they clean up the environment by ridding it of rotting carcasses. This also has the happy effect of limiting the food supply for foxes, whose numbers are lower in devil-populated areas than elsewhere. The worry is that, if devil numbers drop significantly, fox numbers will rise leaving other marsupials vulnerable to predation and making it difficult for Tasmanian devils to make a comeback. The rapid spread of DFTD, the high mortality in affected populations, and a lack of genetic diversity among devils mean there is some urgency to develop strategies to save Tasmanian devils from possible extinction. The management strategy has three main focuses: to define the disease and develop a diagnostic test; to monitor wild populations to track the spread and impact of the disease; and to try to stop the spread of the disease, and establish disease-free populations. This is not as easy as one might think. There is no way to identify infected animals before they show symptoms; researchers don't even know what the blood profile of a healthy devil is, much less what to look for that might be specific for DFTD. And, although it appears to be infectious, the truth is the mechanism of transmission is still unknown. No other species show signs of the disease, not even the devil's closest relative the Eastern quoll, but they could still be reservoirs for the infectious agent. Interestingly, only animals over two years old normally get the disease (a few one-year-old animals have been affected) and this has been exploited to establish two 'insurance populations'. Young leave their mothers and disperse in February/March of each year and up to 60 per cent of them will not survive. This year, two 'insurance populations' were established from young collected during this dispersal. Because of the low genetic diversity, only twenty five animals were required to represent the population, and these were collected from the two genetically distinct populations on the east and west coasts of Tasmania. They are housed away from wild devil populations, under tight quarantine and …