St Nicks

Centre for nature and green living

Spotlight on… Otters

Otter eating a fish

Looking back, it is clear to see that otters (Lutra lutra) had a rather difficult time throughout the 20th century; they were hunted, much of their wetland habitat was destroyed and the introduction of poisonous pesticides led to dramatic declines. When used, these pesticides were washed and leeched into watercourses where they were then ingested by fish. Unfortunately fish are a main food source for otters and so the pesticides were subsequently eaten by the water loving creatures with disastrous consequences to follow. By the 1970s, otters were on the brink of extinction and by the 1980s they had almost completely disappeared from waterways and rivers throughout England. Those populations that were still present in Scotland, Wales and Northern Ireland were smaller and more fragmented than ever.

But don’t fear, the story of the otter does not end there. Not a moment too soon, change began to occur. The late 70s saw legislation against otter hunting introduced and various pesticides were banned from use. When the devastating effects of such pollution were realised, great efforts were made across the country to improve the quality of our waters and after a substantial clean up, rivers and waterways were gradually brought back to life. Fish became more abundant in the once polluted waters and the otters could once again feast safely. Today, otters have extended their once limited range and have returned to many old haunts. They have been recorded in every county in England and although still not common, this is a great sign of recovery for the otter.

Otter on river edge

So now that we know we have a better chance of spotting an otter than ever before, let’s talk about how to identify one. They belong to the Mustelid family, a group of carnivorous animals including weasels, badgers, mink and martens. Otters are riparian mammals, meaning they are semi-aquatic and have adapted to survive using a combination of terrestrial and aquatic habitats. These adaptations mean they will never be found far from rivers, streams and other watercourses. Otters are inquisitive and playful but very secretive creatures and they tend to shy away from people so physical sightings can be few and far between. If you are lucky enough to catch a glimpse of an otter you can recognise them by their dense, light brown fur with a pale underside, long streamlined body with short legs and a broad, flat muzzle with prominent whiskers. Their thick, rudder-like tails and webbed feet are perfect adaptations for a mammal spending a lot of time in water as it makes them very strong, lithe swimmers, managing around one metre per second!

As a result of their elusive and shy nature, otters tend to be nocturnal though can be spotted during the day in areas where watercourses are undisturbed and there is plenty of cover to be found. You really do have to be incredibly fortunate to actually see one so if you do, I suggest buying a lottery ticket – it’s your lucky day! Instead, it is easier to detect the presence of an otter by looking for field signs. Some of the most common field signs that these lovable creatures leave behind include:

Otter anal jelly found on a log at St Nicks

Though there have not yet been any physical sightings of otters here at St Nicks, there have been sure signs that tell us an otter has visited the site. Along Tang Hall beck we have found definite otter spraints, anal jelly and what we think are otter footprints too. Tang Hall beck runs through part of St Nicks woodland and so it seems the habitat is ideal for them – there are plenty of logs, several fallen trees and loads of vegetation cover. Exposed roots of mature trees are perfect lay-up spots, acting as otter hammocks for the playful creatures after a long day of fishing, foraging, frolicking and exploring (w’otter tough life!). The beck has plenty of fish for the otters to nibble on and the woodland provides them with plenty of alternatives if their first menu choice is proving difficult to come by.

Although we have only been teased with field signs on site, there have been confirmed sightings of otters in other areas in York including the River Ouse, the River Foss, in Holtby – further up Osbaldwick Beck, close to the River Derwent and plenty in the River Derwent itself. They were also previously recorded at the Hungate Development site, leading to their habitat there being protected. All of these sightings have inspired optimism at St Nicks that with a little patience, we too will be graced with a rare sighting of the elusive and secretive mammal. Otters can travel across large areas, sometimes using up to 20km of river habitat so it’s possible our lucky day could be just around the river bend!

Volunteers working to improve the banks of the becks at St Nicks

Otters, being at the top of the food chain, are a great indicator species: they require clean water, a varied food supply and abundant vegetation cover so the presence of otters is a brilliant sign of a healthy ecosystem. Over the past few years St Nicks volunteers have done a lot of work to improve the beck and its banks for wildlife. This work has clearly made a huge and positive difference and it seems the otters have noticed the improvement of this habitat. Moving forward, we will need to carry out further otter surveys to monitor those using the site. We will continue improvement work on the banks of the beck and thanks to funding from the Postcode Local Trust, we are also able to move into the next phase of woodland improvements. As part of this project we will further develop St Nicks community woodland, introduce detailed monitoring of woodland species including otters and host various work days and family friendly events to raise awareness to the importance of woodlands. If you think you have what it takes to detect otter field signs why not come along to our Woodland Wanders: Mammal Detectives on Wednesday 14th February to see what you can find?

If you would like to get involved with St Nicks Community Woodland project, take a look at our event listings for upcoming woodland events or contact Volunteer Co-ordinator, Maria Gill on 01904 411821 or for more information.

(All photos in this blog have been taken by St Nicks staff or have been found via public domain sources).


8 February 2018 | Categories: Spotlight on... | Tags: Otter