Mini mammals thriving at Prees Heath

A survey for small mammals conducted by Shropshire Mammal Group on 11th November proved to be one of the most successful surveys of the year. Small mammal surveys provide an opportunity to monitor the numbers of small mammals such as field voles, wood mice and yellow-necked mice, which can be impossible to see without using specialist equipment. 40 Bioecoss Tube Traps were laid out in lines of 10 at 4 different locations across the heath the previous evening with the aim of attracting small mammals. The traps are baited with grain, seeds, apple and casters (fly pupae) and filled with hay, to provide bedding for any visitors into the traps. Once a mouse has ventured in to the trap, it will touch a trigger mechanism, closing a door at the trap entrance, trapping the mammal overnight until we revisit the site to collect the traps in the next morning. Enough food to last a small mammal over 24 hours was used on this occasion as small mammals will be feeding more to gain fat to see them through the colder months.

Tube trap in position

The survey was attended by volunteers from Prees Heath and members of Shropshire Mammal Group on a drizzly, cloudy morning but the weather failed to dampen spirits. Of the 40 traps left out for the night, 16 wood mice, 2 common shrews, 1 field vole and 1 yellow-necked mouse were recorded. Participants were given an opportunity to sex the mammals and see the subtle differences between species by gently scruffing each one. Despite the apparent ideal habitat for voles, large numbers of wood mice were discovered; 90% of which were male. A healthy population of these small mammals indicates a healthy habitat and will ensure that there is plenty of food for the owls and kestrels living around the heath. Shropshire Mammal Group hope to revisit the heath next spring to see how the small mammal population has fared over the winter.


Shrew viewing







Wood mouse

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