Rail traps in or near red squirrel woods

Spring traps (regulated by the Spring Trap Approval Order (Scotland) 2011 and The Spring Traps Approval (Scotland) Amendment Orders 2018 & 2020) are commonly set to target stoats, weasels and rats for the conservation of ground nesting birds¹. A common setting for a spring trap is on a rail (a wooden plank, pole or log) laid across a dry ditch, watercourse or breach in a dyke; this provides a crossing point for these predatory species.

In order to reduce the likelihood of trapping non-target species, such as pine marten and red squirrel, precautions to exclude non target species should be taken. This involves setting the spring trap in an artificial tunnel on the rail and fitting adequate excluders (entrance width restrictor) to help prevent non-target species from entering the trap. Practitioners generally construct rail trap tunnels with weldmesh (25mm over the trap area is recommended) with varying approaches to excluder materials/design that must minimise the risk of capturing, killing or injuring non-target species.

Location of rail traps

The habitat location of rail traps is an important factor affecting the species which might be captured. The trap operator should assess this risk carefully as there are some areas were the risk of catching a non-target species is more likely to occur.

Woodlands which contain red squirrel populations are of particular concern. Red squirrels are a species of conservation concern and priority species for targeted protection because of the risk of exclusion by grey squirrels². It is illegal under the Wildlife and Countryside Act 1981 to:

• Intentionally or recklessly kill, injure or take a red squirrel.
• Set any trap likely to cause bodily injury to any wild animal included in Schedules 5 & 6.
• Damage, destroy or obstruct access to any structure or place that a red squirrel uses for shelter or protection (a drey).
• Disturb a red squirrel when it is occupying a structure or place for that purpose.
• Possess or control, sell, offer for sale or possess or transport for the purpose of sale any live or dead red squirrel or any derivative of such an animal.

Over the years, there has been evidence of a number of red squirrels being found in rail traps located well within red squirrel woodland areas or in close proximity.

Our advice

The GWCT supports the use of well-located, maintained and suitably excluded rail traps in areas outwith red squirrel habitats as part of a game and wildlife conservation management plan.

The GWCT strongly recommends that rail traps should not be used in, or close to woodland where red squirrels are resident. This is will greatly reduce the risk of unintentional capture of red squirrels which can use such rails for crossing waterways. Rail traps currently in use should be removed from such woods.

Ground-located tunnels containing new generation stoat traps such as the DOC 150, Tully or Perdix spring trap, with appropriate excluders (e.g. 40mm core-drilled) might, with careful location, be operated within red squirrel woods as they are less likely to capture protected squirrels. Alternatively, use catch-alive squirrel traps where grey squirrels are the target species but sharing the local environment with its red cousin.

The GWCT’s recommendation to avoid rail trap use in woodland containing red squirrels will be reviewed regularly in line with emerging evidence and the conservation status of red squirrels.

Continued use of rail traps in or close to red squirrel woods could jeopardise future use of rail traps as part of a legitimate predator control programme.

References

1. Tapper, S.C., Potts, G.R., & Brockless, M.H. (1996). The effect of an experimental reduction in predation pressure on the breeding success and population density of grey partridges Perdix perdix. Journal of Applied Ecology, 33: 965-978.
2. Scottish Natural Heritage: Red squirrel