I have had a lot of activity in my Mammal Box, which is positioned next to my garage in a damp and overgrown bank. Wood mice and Bank voles have always visited, with the occasional shrew as well. Since I placed the HD box there, with its high definition camera, I have been able to take a closer look at some of the visitors. It was soon clear that I had the three species of shrew, found in Britain, visiting. It is difficult to gauge size in this box as they all look quite large, but as I played back footage and took stills, I started to realise that they all look very different.
Shrews, although they look like long-nosed mice, are in fact more closely related to moles and are not rodents at all. They belong to the family Soricidae of the order Insectivora. Rodents have teeth that continually grow. Shrews teeth wear down, but they have iron within the enamel of their teeth (which make them look red), to slow this process down, making them much harder. Anyone who has found shrew skulls within owl pellets will know that this coloration is very clear and children often think it is blood on the teeth!
Shrews have a very high metabolic rate and seem to be on ‘fast forward’ all the time! They have an insatiable appetite for insects and worm and can devour their own body weight in a day. In fact, they can die within half a day if deprived of food. The shrews visiting me are eating a range of seeds and dried mealworms. I will be offering some fresh mealworms too. The Water shrew, in particular, is known for its venom, would you believe? Shrews deliver this poison to their pretty via grooves in their teeth. The poison is there to paralyse their prey and not as a form of defence.
So, how can we tell these species apart? The Water shrew is pretty obviously different…. but the Common and Pygmy look similar at first, but on closer examination, it is pretty easy to see the differences.
I have learnt SO much in the last few days, finding out more about these fascinating mammals. I hope this guide helps. I am looking forward to watching these creatures more over the next few months and sharing my footage with you.
– Mammal Society
– The Life of the Shrew By Peter Crowcroft