(PhysOrg.com) -- The deadly bird disease trichomonosis, which has been killing off large numbers of greenfinches and chaffinches in Britain since 2005, has spread to Europe according to a new study published in EcoHealth.
Trichomonosis, caused by the parasite trichomonas gallinae, is commonly associated with doves and pigeons, but crossed the species barrier in 2005 and began affecting finches in the UK. Some areas were hit hard by the parasite, with the chaffinch populations declining by 20 percent and the greenfinch by 35 percent.
Trichomonas gallinae cannot survive for long periods outside of the host and transmission between the birds most likely occurs when birds feed their young through regurgitated food or ingest food and water that has been contaminated by a sick birds saliva.
The new study, carried out by the Zoological Society of London, the University of East Anglia, the British Trust for Ornithology and various other organizations across Europe believe it was the chaffinch that carried the disease out of the UK and into Scandinavia. Since 2008, reports of finch death due to trichomonosis have been seen in Finland, Norway and Sweden. Evidence shows that the chaffinches flew from England in the spring of 2008 to a breeding ground in Fennoscandia and delivered the parasite to the area.
Finches are not the only birds that have been affected by this parasite recently. Trichomonosis has also been diagnosed in the already endangered house sparrow and yellowhammer.
The parasite can cause outbreaks at any time, though deaths tend to occur more often during August and October. Researchers are turning to the public and asking them to report signs of sick birds. Symptoms include fluffed up feathers, lethargy, staying near the feeder and having a difficult time eating and may look wet around the bill. In order to help minimize the spread, people are being asked to regularly clean bird feeding areas and bird baths every couple of weeks and if possible, rotate the area in which the feeder are in. This will help to minimize a build-up of food and bird feces in an area.
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