Last week we began a project to evaluate the value of our recently restored ditches to water voles. Running the project and analysing the data is Alex Hannam, a volunteer who commences a Environmental Science degree in Aberystwyth this autumn.
The methodology is thus: 50 metre transects are marked out along ditches restored last year, 2 years ago, along the river bank (which has not had any particular management for many years) and in a recently created linear pool with no hydrological links. Within these sections all water vole signs are logged and we are able to gauge their value to voles. By repeating the survey over successive summers we can quantify how water vole activity alters as the newer features mature set against the sections of river bank which effectively act as a ‘control’.
Invariably what we are recording are signs of water vole activity rather than the actual animals themselves. Poo, (as any mammal ecologist worth their salt will tell you) is a favourite indicator of water vole activity. Note is taken whether it be a lone poo, (the sort of poo deposited when the vole is caught short while going about it’s daily chores) or a latrine where poos are ritually lain to mark a territory. The slender stems of reed, rush and other marginal vegetation chewed neatly off at 45 degrees is another sure sign of water voles. The greenness or otherwise of these stem sections indicates the freshness of the activity - a fact often true of poos too which are lain green and fade to brown.
A stem gnawed at 45 degrees...
A latrine on a bankside willow trunk...
...and a collection of chewed and discarded stems all good indicators of water vole activity.
Chewed stems are often found in ‘gardens’ - small openings within tall waterside vegetation often with escape tunnels or well trodden paths to the relative safety of the river. Burrows are another sign within the banks themselves and often too set well back from the bank. If active the slide too and from the hole will be well pawed and free of vegetation.
The task of acquiring water vole data - although not unpleasant to my mind, (at least not on a sunny summers day it) - does rather require the ‘head down harris raised’ approach to get in amongst the emergent bank side vegetation - in a manner not wholly unlike that beloved of primetime David Bellamy. The Bellamy approach, (as the man himself was often apt to mention) does open up a world which could otherwise pass us by… like this delightful common frog.
...This freshly minted peacock.
... and the magnificent hoverfly Volucellini zonaria on hemp agrimony.
Pleasingly, from the perspective of this project, water vole signs were found along all the transects and some interesting patterns are emerging interms the amount of activity, specific bankside vegetation types and the relative ages of the water features. More will be revealed as the project runs no doubt...
... and all for the love of dear old Ratty.
Thanks guys. Not sure which of Irene or Alex most resembles Bellamy however Frank. No doubting the Terry Nutkins impersonator however...