A project to adapt the culverts under a section of the A9 in Perthshire by installing ramps, steps and headlight reflectors installed at otter-height was completed in November and is thought to have reduced the number of animals crossing the road.

It is one of various wildlife support schemes commissioned by government agency Transport Scotland as part of the transport network’s maintenance and upgrade.

Angus Corby, landscape advisor at Transport Scotland, said: “So far, the otter-friendly culverts and reflector system have provided excellent results in deterring otters from crossing the road and we’re delighted with this outcome.

“We have been working together with Scotland Transerv for a number of years across north-west Scotland on this, and other projects, with the aim of reducing wildlife fatalities and protecting species found on the network, and it is satisfying to see these efforts rewarded.”

Built within the stream cascades, the mini steps, ramps and entry points help the animals to scramble up and down the under-road drainage tunnels. Their safety is also aided by roadside fences which guide them into these safe passageways. Reflectors at the edge of the carriageway shine vehicle headlights at the otter’s eye level, aiming to put the creatures off trying to cross the road.

The project came about following reports from a local wildlife group, Pitlochry Scottish Wildlife Trust, of increasing numbers of the otters, which are designated protected species under European conservation guidelines, being hit by vehicles on the trunk road.

There have been no reported otter deaths at the sites since work to change the culverts began in 2007. More than 20 otters were killed at one location on the road during the previous five years.

The decision to adapt the original drainage system followed an investigation of otter movements around Loch Faskally and the rivers Tay and Tummel.