Nature lovers are becoming worried by the effect of a parasite that causes popular garden birds to have trouble feeding.

The trichomonad parasite bug blocks birds' throats causing them to appear lethargic and regurgitate their food.

The organism was originally carried by pigeons but has now spread to finches.

Although the parasite cannot be caught by other animals or by humans, it has affected a number of birds across the country during the autumn months.

Kirsi Peck of the RSPB told the Lancashire Evening Post: "Greenfinches are getting particularly badly hammered by it. We rely on people reporting cases to find where the outbreaks are."

Paul Ellis, secretary of Fylde Bird Club in Lancashire, said: "The best advice you can give people is to clean their bird feeders on a regular basis as that's how it can be passed on."

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