This project will help us to understand more about the distribution and population status of otters in each of the North Isles. The information found through this project will also help to estimate the number of otters present across the whole of Orkney.
Part of the project will focus on surveying stretches of coastline of each island for signs of otters – spraint, footprints, otter holts etc. This information will be used to create an estimate of numbers and ascertain the typical areas favoured by otters and places where they are less likely to be present. A more focused project will be undertaken in Eday where the study will look at habitat preferences and population dynamics.
As well as coastal surveys, sightings of otters will help build up a general picture of their activity – such as seasonal changes in behaviour. Additional information, such as food being eaten, whether cubs are present or regular patterns of activity that you may be aware of are also very useful.
Results from surveys in 2020 and 2021
In winter 2019/2020 we focused our work in Eday and also undertook a coastal survey in North Ronaldsay. In 2021 we again looked at Eday and also Stronsay and Sanday.
Eday
The video below shows trail camera footage of a female otter and two female cubs in Eday. She has a third, male cub who is more adventurous and is already branching out on his own.
Survey results from Eday have shown that otters were active all around the island, with clusters of activity in places that were particularly suitable for holts (otter dens) - often low lying areas of coast where peaty soil was present. Trail camera footage revealed activity in other, less likely places too - such as on high moorland hills.
Up to seven family groups (mothers with cubs) have been observed in a single year (2021) on cameras at different locations around the island, but evidence from the coastal survey suggested that there may have been other family groups present too, that were not caught on camera.
The presence of cubs makes identifying individual female otters a little easier than males. However, at least two separate male individuals were seen in 2020 - with a very high likelyhood of many more being present.
North Ronaldsay
There have been very few recorded sightings of otters in North Ronaldsay in recent years but survey results showed that they are still present and a single animal was caught on camera. Later a male otter was seen regularly by residents around the island over a number of months. The survey indicated that North Ronaldsay has only a small population of otters - work will continue in 2021 to find out more.
Sanday
Otters are frequently sighted in Sanday on many areas around the coast. Sanday has lots of freshwater, which is essential for Otters to drink and clean salt from their fur, there are also extensive kelp beds ofshore that will provide excellent foraging grounds. However, Otters are often thought to favour peaty habitats for their resting places, and Sanday has almost no peat. This doesn't appear to be a significant limiting factor though, as nearly all the coastlines surveyed showed signs of Otter ranges, with animals finding resting places or holts in a variety of locations, including old buildings, sand dunes, rock piles and old rabbit burrows.
Stronsay
The survey in Stronsay was undertaken in 2021 during a period of snowfall. This made surveying difficult because many signs were hidden under snow but conversely, footprints and other signs could be found.
Where to send your records
Send your otter sightings to any of the following:
- county mammal recorder Brian Ribbands email: [email protected]
- or to the Orkney Wildlife Information and Records Centre email: [email protected]
If you have additional information about otters in your area, such as:
- an otter that you see regularly;
- evidence of an otter living near you;
- behavioural or dietary traits you have noticed;
contact Anne Bignall, email: [email protected]
Volunteer opportunity
We will be recruiting a small team of volunteers to help survey coastlines for signs of otters during the winter. You’ll need to be able to walk over rough terrain for up to 10km, happy to travel to other islands and prepared for the cold! Training will be given and expenses paid for trips to islands and any overnight stays. Open to all, but priority given to North Isles residents. To find out more contact Anne Bignall, email [email protected].