Drivers in Cumbria are being urged to report the bodies of dead otters to help a project monitoring the health of wildlife in England and Wales.
Otter numbers are increasing in England and Wales
The roadkill is collected by the Environment Agency and sent to Cardiff University for a post-mortem to assess its quality of life before death.
A spokeswoman for the agency said the examinations were useful in assessing the impact of pesticides on wildlife.
The study has already revealed that the otter population is increasing.
Gail Buttrill, of the Environment Agency, said more than 1,000 dead otters had been examined at the university during a 15-year period.
She said: "It is sad that the biggest threat to otters is getting killed on the roads and it is particularly sad when it is a female who may have cubs out in the wild.
"However, for our monitoring it is essential that people call in to our hotline number and so we can arrange to come and pick-up the otters bodies.
"It has helped us to look at the health of the population and see how man made chemicals are accumulating in wild animals."