A surprise find

A small mammal survey on two Langdyke reserves at Etton and Maxey came up with a surprise find.

Steve and Liz Lonsdale, who are licensed to carry out the surveys found two house mice – not the type of mouse normal found outside – alongside the allotment area at Etton’s High Meadow.

A number of wood mice were found at both reserves as well – including the one in the main picture above.

Steve busy checking one of the traps

Steve explained: “The House Mice were unexpected – nowadays they are only found near grain stores or chicken farms. 

“It is possible that they have been introduced into the allotment area as part of a chicken manure or other delivery.”

The surveys were conducted at High Meadow and in North Wood at Etton Maxey Pits – the first time this area has been surveyed.
Liz Lonsdale recording the weight of one of the finds

At High Meadow 42 Longworth ‘live traps’ were set on the evening of Saturday August 22, and checked at 12 hourly intervals until the morning of Monday August 24.

32 of the traps were set in pairs around the edge of the north-eastern meadow, and the remaining 10 in pairs around the barn and allotment. There was a reasonable capture rate of a variety of species: wood mice, field voles and common shrew but Bank voles proved elusive.

Sunday Morning: 10 Wood Mice; 1 Bank Vole
Sunday Evening: 1 Field Vole; 6 Common Shrews; 1 Pygmy Shrew
Monday Morning: 12 Wood Mice (including 2 recaptures); 2 House Mice; 12 Common Shrews (including 3 recaptures).
The high catch rates and low recapture rates indicate a good population of Wood Mice and Common Shrews.

Etton-Maxey – Saturday  August29 to Monday  August 31
14 Longworth ‘live traps’ were set on the Saturday , and a further 28 on that evening.  The traps were checked at 12 hourly intervals until the morning of Monday August 31. The traps were set in three groups in north meadow.

Saturday Evening: 2 Field Voles;
Sunday Morning: 5 Field Voles (inc 2 recaptures); 1 Common Shrew; 9 Wood Mice
Sunday Evening 4 Field Voles (inc 3 recaptures); 3 Common Shrews (inc 1 recapture); 2 Wood Mice (inc 1 recapture);
Monday Morning: 3 Field Voles (inc 1 recapture); 6 Common Shrews (inc 1 recapture); 6 Wood Mice (inc 3 recaptures); Catch rates were marginally higher than expected, which would indicate good populations of small mammals.  

Steve and Liz have been surveying for mammals (and small mammals in particular) for more than 30 years, starting in Derbyshire, where they had significant input into the Derbyshire Mammal Atlas, and for the last five years around here since we moved to Maxey.

Steve said: “Most of the surveys we do are in sites chosen by us where we think it would be productive /useful to have some idea of the species present, sometimes as part of national surveys, sometimes as part of local surveys or for local groups, and sometimes on our own to generate useful records.
“Where appropriate we approach the landowner / wildlife group (in this case Langdyke CT) for permission to survey, but the responsibility for the session lies with us. All our records (not just specific survey records) are fed into (what is now), iRecord, where they are visible to all iRecord users, and also to the local wildlife group / landowner as appropriate.
“In order to survey using live traps for small mammals, including shrews, we have to hold a licence. Where others are present who do not have a licence we are responsible for the welfare of the animals being surveyed for.
“Live trapping can be done at any time of year, and indeed some groups do so throughout the year. However, our methodology is to check the traps every 12 hours, and to do so in daylight we only trap between April and September.”
Most  of the live traps they use (‘Longworths’) are made of aluminium and so, even while bedding and food are supplied within them, they can be cold overnight in winter.
“Our methodology is to set traps in an evening session, and check them the following morning, evening, and again the following morning (ie 1 session to set and 3 to check).
“Small mammals vary in their habits, and so we expect different species in the morning and evening sessions; some animals are ‘trap-shy’, so they take longer to catch, hence the 3 checking sessions rather than 1.