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Credit: Tasmanian times
With only 1500 forty-spotted pardalote in the world, extinction threatens. Assumed causes were loss of habitat, drought & possums, until Amanda Edworthy, PhD student from the Australian National University in Canberra, suspected that parasitic fly larvae were causing the 15% fledge rate in chicks. To test her hypothesis, she spent the last three summers climbing trees to nests to spray with a plant-based insecticide which does not affect the chicks.
Result: 15% fledge rate leapt to 90%.
Next problem: how to protect the chicks without so much tree climbing.
Possible solution: in the Galapagos Islands, Darwin's Finches1 are threatened in a similar way. Solution is to spray the insecticide onto small balls of cotton-wool, & attach them to bushes with wire. Small nesting birds collect soft, fibrous material to line their nests. When they line their nests with fibres of cotton-wool laced with insecticide, the parasite problem is reduced or eliminated.
Over the next two summers, the cotton-wool method will be trialled with the forty-spotted pardalote.
http://www.abc.net.au/am/content/2015/s4302953.htm
http://www.parks.tas.gov.au/index.aspx?id=5207
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1 "Darwin's finches", https://en.wikipedia.org/wiki/Darwin%27s_finches / cotton-wool fight to save one of Australia's most endangered animals species new study tiny fly larvae killing forty-spotted pardalote cotton wool prevent the small bird disappearing completely small bird big problem species endangered 1500 left in the world southern Tasmania Amanda Edworthy PhD student candidate Australian National University ANU Canberra last three summers climbing trees studying study bird driven the population down biggest threat that we found parasitic fly adults lay maggot larvae nest eggs larvae burrow underneath skin nestling feed on blood 75 per cent mortality researcher loss of habitat drought possums reaching into nest boxes larvae larva discovery Amanda Edworthy's high-up nests spraying mild plant-based insecticide 15 per cent of nestlings survive fly spray kill off almost all the parasites fledge rate 90 per cent aurvival surviving effective practical search more manageable solution Galapagos Islands fly larvae problem endangered Darwin's Finches Scientists access bird's nests cotton-wool method Sonia Kliendorfer professor animal behaviour Flinders University Adelaide cotton wool method spraying little balls of cotton plant-based insecticide kills lava parasitic fly does not harm birds researches cotton wool intertwined with wire bush tears off small pieces weave into its nest birds naturally search soft warm insulating material conservation behaviour using insights animal behaviour inform conservation cotton-wool method trialled forty-spotted pardalote next two years buy the small bird some time birds hang on in the short-term long-term important to figure out why parasite loads have increased increased manage forests reduce fly populations in general researcher Amanda Edworthy /
