By Tomos Williams
NatureSpy recently sent some of our camera traps out an assignment to the North Wales Wildlife Trust at their Cemlyn Nature Reserve.
The site is home to a range of rare bird species and this year has had new visitors; Eurasian otters.
Wardens at the site came across otter spraints, left behind to mark territory. They placed the cameras near these spraint sites with the hope of capturing otter behaviour and they were not disappointed…
An otter leaves a spraint to mark its territory
Otter spraints are slimy, dark and have distinct smells. Sometimes the spraints will smell of putrefied fish and sometimes they will smell of things like jasmine and lavender.
As otters are rare in the UK, most population surveys depend on spraint density to estimate the number of individuals in an area. The density of spraints usually correlates to the density of otters.
Eurasian otters are said to be the most territorial of all the otter species. They routinely mark the boundaries of their very large territories with spraints to ward off other individuals.
An otter yawns in front of the camera
Eurasian otters can be found from North Korea to the UK and as far south as Morocco. In the 1980s, their population sank to an all time low in the UK due to pollution and hunting but their numbers have been recovering in recent years. “Having the otters around has been fantastic, I was jumping for joy when I first saw them!” said warden Dawn Wilde. “They’re a protected species and it also shows good biodiversity and that the habitat is clean and healthy.”
A pair of otters pass by in the early morning
Otters need to eat up to 15% of their body weight daily; they therefore eat a lot of fish, invertebrates and water birds, making the Cemlyn Bay reserve an ideal place for them to live.
“Although they do eat some birds, the spraints have crab in them and there are a lot of mullet in the lagoon” explains Dawn.
“They might be a predator of the birds but there are plenty of different food sources for them and there are many other predators about.”
The naturally playful animals live under large rocks and tree roots in dens which are called ‘holts’.
Three otters move through the grass
