Life under the soil: The biology and ecology of moles

The European mole is a strange and elusive mammal that is surprisingly widespread and common in the UK even though not many people have ever seen one. They are in the Eulipotyphla order that also includes shrews and hedgehogs. This talk into their ecology was given to the Rutland and Leicestershire Wildlife Trust.

Moles are highly adapted to life underground with larger front feet for digging, sharp back claws to act as an anchor, very sensitive nose and whiskers, short hair that brush both ways, sensitive tail hairs that act like whiskers and a flexible spine. They live on average for 2-3 years but are thought to live up to 8 years. Moles are also not all black with some being whitish, silvery and even orange!

The skeleton of a European mole, here you can see key adaptations such 

as large front feet, sharp claws and a long snout. (© Ric Morris)

Moles live in a range of habitats as long as there is a large enough layer of soil; they have even been found on the tops of Snowdonia! The occupancy of moles at a site can be estimated by the presence of mole hills; however, it is hard to determine the age of the mole hills therefore they may not still be present. It is even harder to count the actual the number of individuals present; this can be done by the number of mole hills but there are too many variables affecting this such as soil type, distance apart and food.

Even though moles spend the vast majority of their life underground they are still at risk from predators. Birds of prey, foxes and grey herons will all take moles if they are caught above ground however, their main predator is the weasel that is small enough to fit into the mole tunnels and catch the moles.    

Some may be surprised to learn that moles build raised fortresses to mitigate against flooding (normally contains the nesting chamber) and sort of reminds me of a beaver’s lodge but out of mud. Moles also of course dig tunnels which results in mole hills; these tunnel systems have been found do be 1km. By digging tunnels and placing the unwanted mud on the surface moles help to aerate the soil increasing its quality. However, mole hills also contaminate grass pastures, damage crops and are unsightly to some resulting in them being considered as a pest and are controlled in many areas.

This image seems to show an unusual pattern of mole hills that are in lines that cross; it 

has been suggested this could be a male and female meeting and shows that moles must

 have some sense of direction though no one has proved this theory. (© Derek Crawley)

Though the European mole seems to be doing fine in the UK, the difficulty with surveying them and problems with not knowing the age of mole hills could make them vulnerable to population declines without anyone knowing until it is too late.  

I must admit I do know very little about the biology and ecology of moles even though they are one of the commonest mammals in the UK. This talk was a real eyeopener into their secret life and also some of the important role’s moles play. Moles are could be used as an indicator for healthy soil as high abundance would suggest large numbers of soil invertebrates. 

Moles play an important role in a healthy balanced ecosystem and in the future if I was to work in reserve management this talk has taught me not to forget the humble mole. 

Link to talk