Researchers at the Queen's University Belfast have found that the spread of an exotic parasite that threatens the UK's honeybee population could be speeded up by global warming.

The gut parasite Nosema ceranae - which originates in Asia but can now be found worldwide - is likely to cause increasing damage to UK bees as the Earth heats up through climate change.

The new finding suggests that this parasite not only has a superior competitive ability, but that its numbers could rise with climate change, researchers said.

"This emerging parasite is more susceptible to cold than its original close relative, possibly reflecting its presumed origin in east Asia," co-author of the study and Adjunct Reader at Queen's School of Biological Sciences, Professor Robert Paxton said.

"In the face of rising global temperatures, our findings suggest that it will increase in prevalence and potentially lead to increased honeybee colony losses in Britain," said Paxton.

"Our results reveal not only that the exotic parasite is a better competitor than its original close relative, but that its widespread distribution and patterns of prevalence in nature depend on climatic conditions too," co-researcher Myrsini Natsopoulou, from the Martin-Luther-Universitat Halle-Wittenberg in Germany said.

The research compared pathogen growth in honeybees that were infected with both the exotic parasite, Nosema ceranae and its original native relative, Nosema apis.

Experiments showed that, while both parasites inhibit each other's growth, the exotic Nosema ceranae has a much greater negative impact on the native Nosema apis than vice versa.

By integrating the effects of competition and climate into a simple mathematical model, the researchers were better able to predict the relative occurrence of both parasite species in nature: Nosema ceranae is common in Southern Europe but rare in Northern Europe.

The study was published in the journal Proceedings of the Royal Society B.