Rum has UK's biggest earthworms, Lancashire scientists say
A Scottish island is home to the UK's largest earthworms, according to researchers from the University of Central Lancashire in Preston.
The common species Lumbricus terrestris found on Rum are more than three times the weight and length of the average earthworm.
The researchers found the island worms growing to almost 15in (40cm) in length.
A lack of predators and fertile soil have helped to boost their size.
Rum's "optimum conditions" also mean its worms could be living for up to 10 years when worms elsewhere in UK have a lifespan of about two years.
The research has been published in the Scottish peer-reviewed scientific journal, The Glasgow Naturalist.
It draws on university scientists' investigations in 2006 to 2011 of "very large" worm burrows.
Kevin Butt, professor at the University of Central Lancashire who led the study, said: "I first noticed the large worm burrows in 2005, so I had my suspicions that there may be some pretty big worms in the area.
"We went back out to investigate this the following year and finding worms of this size was very exciting, especially when the Natural History Museum team confirmed that they had no specimens like this."
He added: "There are still unanswered questions and we plan to continue our research to find out as much as possible about these creatures.
"We're also looking forward to exploring more rural areas in the UK and abroad, in the hope that we will make more exciting discoveries like this."