10/09/16 - Field Voles & flailing

Now that the farmers have just about finished their work in the valleys meadows, it’s that time of year when the team take their turn behind the wheel of our tractor. Each year following the hay cut, during August/September we spend time flailing the wetter and ranker vegetation that has been left around the scrapes such as the sedges, rushes and Glyceria, and the Meadowsweet and docks left along the fence lines. By cutting the rank vegetation it will help to prevent the area becoming a mono-culture dominated by just one or two species, and hopefully halt any further spread from the edges of the meadows into the botanically rich areas. Flailing the ditch sides and bunds also improves them for nesting, and feeding/loafing areas by many species of birds, whilst providing a mosaic of habitat structure for invertebrates as well as maintaining view lines for visitors using the hides. 

Last week whilst heading back to the base after a morning spent flailing, we heard the squeaking of a small mammal coming from the grass beneath us. On closer inspection - and within a few feet from the tractors wheels – we discovered a small pile of grass containing the nest of a Field Vole with four small young in it. Field Voles often nest under grassy tussocks, or occasionally in underground burrows, and have on average six litters a year, varying between 3-7 young.

Field Voles are prolific breeders, with populations in favourable habitat often increasing to thousands, in what is known as a ‘vole plague’. When this happens, competition for space, food and increased aggression leads to less successful breeding, with the result being a population decline. Due to the fluctuations in the population, it can then impact on the predators that feed on them, such as our Barn Owls – with Field Voles forming 90% of their diet – fortunately we haven’t noticed a shortage this year, with a number of extra voles found in the boxes during our checks.