Otter-Proof fencing can be an essential tool in protecting your fishery but it’s not a matter of installing your fence and then forgetting about it. Simple checks and maintenance are essential if your fence is to stay in good shape and do the job it was built for. Fisheries Management Advisor and Angling Trust predation expert Richard Bamforth has sound advice for all stillwater fisheries with otter fencing.

“As the water temperature begins to fall and rivers are more inclined to flood over the coming months, otter predation tends to become an increased risk on those stillwaters containing valuable carp. But what can be done?

Over the past few years, many fisheries have invested heavily in otter fencing, with the Angling Trust assisting by securing hundreds of thousands of pounds via the AIF (Angling Improvement Fund) to help those in most need. However, these defences don’t maintain themselves and are only as good as their weakest point!

For those fisheries fortunate enough to have an otter fence, now is the ideal time to carry out some essential maintenance checks. On many fenced fisheries this is already common practice, with regular fence line patrols being undertaken, often daily. For others, however, it can sadly be just an afterthought when a prized fish turns up ‘ottered’.

A few constructive hours spent now, could save potential heartache over the coming months. The following pointers may seem obvious to most, but unfortunately every year otters find their way into fenced sites.

Otter fencing checklist: How safe are your defences?

With Britian’s otter population here to stay, complacency isn’t an option for fisheries! Sound maintenance begins with having regular checks and doing your best to follow best practice. Here is a handy list of tasks and and factors to look out for.

• It’s essential your boundary fence is checked immediately following severe gales and any damage repaired immediately!
• To assist with the visual inspection of the fence line, encroaching vegetation may need to be controlled, or cut back on a regular basis. Avoid using brush-cutters, however, since these can easily damage and cut the fence wire.
• Ensure that all inlets & outlets, both above & below the water level are secure and otter proof. Some of these may need to be constructed so the grills can be removed and cleared of debris especially following periods of heavy rainfall.
• Any low overhanging, dead, dying or diseased trees surrounding the fence should be removed. (Where appropriate, seek professional advice regarding roosting/hibernating bats).

• If a ‘skirt’ has been incorporated within the fence design, ensure this is securely affixed to the ground along its entire length and ideally covered with soil, turf or aggregate.
• Ensure that all fence posts and especially straining posts/struts are erected inside the fence line to prevent them acting as a ramp thereby providing an otter with the opportunity to climb.
• Where two rolls of wire have been joined together, ensure that the spacing remains no greater than 50mm.
• · Ensure that no fence wires have become broken or splayed over time, paying attention towards those at ground level.

• Gates should be hung so that when closed there is no gap greater than 50mm on either the hanging or clashing side, or underneath the gate, whereby an otter may gain access. And ensure there is a solid base beneath the gate to prevent an otter being able to dig underneath.
• Clearly sign post your gates to highlight that they need to be always kept securely closed and ideally incorporate a self-closing mechanism. Replace any damaged or missing signs and ensure that all members and visitors remain vigilant.
• Consider using combination locks, especially on gates which are infrequently used.
• Look for possible entry points being dug in, or out by rabbits, badgers etc.
• Unfortunately, some sites have suffered from deliberate vandalism of their fence lines, with holes being cut through the fence. Stay vigilant and do your best to maintain good relations with the neighbouring community!
• Try to get into good habits with inspecting your fence. Having one or a small handful of people to do this routinely at regular intervals will help to make sure any issues are picked up early.
• For those sites which use either plain electric wire fences (whether singular or multiple lines); temporary electric netting; or electric scare wires in addition to a ‘barrier’ fence, it is imperative that the power supply is both adequate and maintained, and set on a fast pulse.  Maintain the tension along the plain wires and do not allow too wide a spacing.  One of the most crucial points is to ensure that the fence is NOT shorting out at any point along its entire length, caused by overhanging vegetation, or fallen branches etc.  For those sites which use timers, please be aware that otter can be active during daylight hours.

Further useful sources and contacts

Narrated Presentation by Richard Bamforth on Otter Fence Maintenance

We have two full time predation experts who are available to give free advice.

Jake Davoile (SOUTH)
Telephone 07949 703 206
Email: Jake.davoile@anglingtrust.net

Richard Bamforth (NORTH)
Telephone 07904 041 518
Email: richard.bamforth@anglingtrust.net

The Angling Improvement Fund

For clubs and fisheries that face predation issues but have yet to install defences, the Angling Improvement Fund may be able to help. While they are unlikely to fund this alone, match funding is a typical solution, with those clubs that give maximum value to local communities prioritised. For further information see our main website.

Previous blog posts on predation

For those in search of more information and case studies, our blog archives also contain some interesting articles to read, including:

Cormorants, keys and surveillance: A day with predation and fisheries expert Jake Davoile: We join Jake on a Midlands stillwater to look at anti-predation measures and how Angling Trust staff can help fisheries, from natural cover to cormorant deterrents.

The Angling Improvement Fund in action at Andy’s Lake: Dom Garnett meets fishery owner Paul Mundy to see how otter fencing can help protect specimen fish.

*Photo credit for Header Photo of Otter. Dave Webb/UKWOT