Short-eared owls - the pale hunters of the Derbyshire moors
PUBLISHED: 00:00 21 November 2019
Paul Hobson investigates the enigmatic short-eared owl, a lover of wide open spaces
Most people will be familiar with the tell-tale hoot of the tawny owl - or wood owl as it was once better known - and with the barn owl, that deathly white, silent assassin of our fields and graveyards. However, because of our region's excellent varied habitats, we are fortunate that with just a bit of effort and knowledge we are able to see all five UK breeding owls locally.
Little owls love open parkland and rough farmland and long-eared owls are birds of the woodland. However, it's the short-eared owl that is arguably our most enigmatic species and, fortunately for us, it is a lover of wide open spaces.
All owls are hunters and their morphology (body shape and build) is supremely adapted to this precise purpose. To watch a shortie hunting is a lesson in patience and the practice of finely-honed skills. The pale, long-winged bird starts by gliding low and slowly over a length of chosen moor. Its head will be constantly turning as it tries to pick up the faintest of rustles in the heather and grasses below. Once it thinks it has heard or spotted a vole it may hover for a few seconds to locate its tasty target precisely, before folding its wings back and plunging headfirst into the vegetation.
This is the time when patience is necessary because in most cases it misses the furry meal and has to start all over again. If it is successful, the vole or field mouse (usually a vole) is swallowed whole and the bird may even stay put for a post-meal nap. In times of plenty, shorties will stash away any excess food to be picked up later on lean days.
Hunting is very weather dependent for all owls but arguably more so for shorties. This is particularly the case in summer as the breeding population is generally confined to the higher moors in the north and west of the county and the Peak District. Here, when it is windy, it is really windy and the constant buffeting of the wind on the long heather and moor grasses effectively masks the sounds of the toing and froing of the short-tailed or field voles. Wet weather is a double whammy and if the birds are hunting to feed growing chicks they often struggle so much in poor summers that many chicks starve.
Derbyshire's shorties can be divided into two distinct groups: a winter and a summer population. Our summer birds return to the moors in March and, if successful in raising a family, will tend to leave the following August. The winter population is more mobile. They don't need territories as they are not breeding and so there are both local birds and continental birds that have arrived to overwinter here. The exact number of owls is difficult to determine and it varies year on year as the population of their favourite prey - short-tailed voles - is very dynamic.
The winter and summer groups can also be distinguished from each other by location. The high, exposed moors are deserted in winter because the increasingly harsh weather makes hunting less reliable. The winter population lives at a lower elevation, hunting rough, grassy fields that have high vole populations. In good years the vole population can explode and shorties from far and wide will congregate to exploit the abundance. I watched eight owls hunting one huge, rough, grass field a few years ago. The experience was absolutely amazing and the highlight was when two owls flew up and had a talon to talon skirmish above me. The photographs were not the best but they are a perfect reminder of the fantastic drama played out on that cold winter day.
Short-eared owls are probably the least cosmopolitan of our five owls when it comes to their diet. During the breeding season they will live almost exclusively on short-tailed voles. These are our largest voles and live in rough grassland and heather moorland.
A few years ago I spent a month photographing a pair of shorties that were breeding on a remote piece of moorland beyond the Snake Pass. As the breeding season lengthened I started to find a lot of owl pellets - the regurgitated fur and bones of their prey. I had learned years before how to analyse them, so after soaking them in water and teasing them apart with tweezers, I spent hours identifying the skulls and jaws of their rodent diet. Except for one leg bone of a frog, I only ever found the remains of short-tailed voles.
Short-eared owls' winter diet can be a little more varied. I have watched shorties hunting in winter many times and have never seen anything other than a mouse or vole taken but I have been told that their winter larder can also contain small birds, rabbits and frogs.
Owls are considered to be mainly nocturnal, and for tawny and long-eared owls this is mostly true. However, barn and short-eared owls will hunt for many hours in daylight, particularly in the first few hours after dawn and just before dusk. This makes them far more easily watchable. Winter is the easiest season to watch our shorties, the days are shorter and the owls will use more of the daylight hours to hunt. I have found that days of calm weather after rainy or windy weather are particularly good. However, you should always be prepared to come across one of our breeding owls when out walking on the moors or driving across them, even in places you don't expect.
Last June when I was driving to Hathersage to meet a couple of friends for breakfast a shortie skimmed across the road just in front of my car as I drove past Burbage at 8.30am, four hours after dawn. A fantastic pre-breakfast experience.