Monday, 15 February 2016

Small Mammal View

I have long wanted to better understand the small mammals on my patch. I have recently purchased a number of Longworth traps but do not want to use them whilst the weather is still so cold.

In the past I have managed to get some footage of mice on my standard Bushnell trail camera but these are very small in size and hard to identify. I have seen on Springwatch and on other blogs some really nice clips of small mammals and I also knew that one of the Bushnell models came with a close focus lens. Unfortunately this model is very expensive but a quick web search revealed a company http://www.wildlifeservices.co.uk/ that sold Acorn and Bushnells with an added lens for close up work. Further investigation showed that they also sold a mammal box. (https://shop.naturespy.org/product/small-mammal-box/

The camera and box were dispatched at a reasonable price and with minimal delay. All in all customer service was excellent. I was then able to set to work making a few modifications.

I did not want larger mammals like squirrels or birds to get in and I wanted some way to measure the mammals that entered. To do this I added a hinged flap with a grid of 1cm squares to the inside.

Mammal Cam Trap in situ

With modifications made I then tested it in the garden which revealed I needed to turn down the
Infra Red lights, I did this by covering up the top most rows with tape.

Sure that I was ready I placed the camera out on my patch for a night. The video below shows what I caught.

video

The video seems to show a Bank Vole. The tail is about as long as half the head and body and the body as well as tail was dark above and pale below. Over the night the vole returned to remove nearly all the bait, seed and peanuts. At one point you can see an encounter between two individuals where they exhibit some highly vocal squeaks during a short tussle.

I hope to carry out this experiment several times more with variable baits. I know shrews are on the site and so some live insect baits will help coax them into view.

As a first attempt I am very pleased with the results, I need to practice aligning the camera better and  like the fact that the grid lines worked making it easier to measure the individuals. This should be a valuable addition to my long term camera trap survey.