Three Norfolk youngsters have appeared on prime time television as part of a national hunt for an invasive visitor from Spain.

Spanish slugs are thought to be an aggressive species, capable of destroying crops and may be responsible for the death of numerous hedgehogs. The problems caused by the creatures was highlighted on Sunday's BBC programme Countryfile when they visited a Hethersett garden.

Annie Floyd, 13, from Hethersett, Lily-Ann Reeve, 13, from Tasburgh and 12-year-old Rhiannon Smith-Meek, from Norwich, have been taking part in a citizens science project aimed at tracking down the Spanish slugs.

Their search has been aided by friend Dr Anne Edwards, a research assistant at the John Innes Centre, a Hethersett parish councillor, member of the Hethersett Environmental Action Team and an authority on the ash dieback disease.

She was contacted by the Countryfile programme and asked for her expert knowledge on the unwelcome Spanish visitors. Knowing of the girls' interest in nature, she enlisted their help.

'There is a slugwatch website which was set up by a pupil from the Notre Dame School in Norwich,' she said.

'The Spanish slugs tend to be larger than their British counterparts and often feed on dog droppings and dead animals. They carry parasites and it takes lots of slug pellets to kill them.

'Hedgehogs may have eaten them and suffered serious consequences. They emit masses of slime and can lay 400 eggs at a time, twice as many as their British counterparts. There is a serious economic consequence as the creatures are capable of destroying crops.'

The slugs are thought to have been brought to this country about two years ago in various consignments. They were first identified by Dr Ian Bedford, head of entomology at the John Innes Centre.

Although they failed to find any slugs in the Hethersett garden, the three girls, who are now known locally as The Slugettes, were keen to pass on their knowledge to others in a bid to eradicate the creatures which have orange or brown backs and can grow up to six inches in length.

They all agreed that being on national TV was an 'amazing experience'.

Annie and Lily-Ann are pupils at Hethersett Academy and Rhiannon attends the Notre Dame School in Norwich.