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The Barn Owl – UK Endangered Species
It is dusk, a warm summer evening somewhere in the British Isles. A pale, ghostly shape glides over the fields, watching with sharp eyes for its prey. It flies low over the rough pasture, hovering over a tangle of grasses where it has detected a slight movement and swoops down on the terrified, quivering vole that is trying to conceal itself there. This ashen phantom of the night is the Barn Owl, and in the UK is one of the most recognisable and loved of our five native owl species. But like many of our native bird species, in the past few decades Barn Owl numbers have severely declined. So where and how do these owls live and why have the numbers of this striking bird of prey declined so much over the years?
The scientific name for the Barn Owl is Tyto alba alba and this superb bird of prey is the apex avian predator of our British lowland farms. If they are resident in an area it means that the surrounding countryside is well stocked with prey animals such as voles, shrews and mice and that there are suitable nesting sites available for them to use. They are very distinctive looking birds that have white feathered, heart shaped faces, light golden brown feathers on their upper bodies and creamy silver feathers on their under parts. The shape of their heart shaped face is not just for decoration, it helps the barn owl with its exceptionally keen hearing as it helps to trap sound and funnel it towards their ears. They can hunt by sound alone, and their ears are also positioned differently on either side of their head, with the left ear being in a higher position than their right ear. This positioning of their ears helps them when they are flying and hunting, as it allows them to detect whether a noise is coming from above them or from below them. Although the noise that we usually associate with owls at night is hooting, barn owls can shriek and hiss but they do not hoot, and if you do hear hooting during the night it will be because a tawny owl is in the vicinity.
They have bodies that are superbly adapted for hunting with very long legs and sharp talons that allow them to grip prey animals and rip them from the grass and vegetation they hide in. They also have very long wings in comparison to their body size, and this helps them when they are flying slowly and hovering over the ground locating their prey. Barn owls will hunt every night for food and can catch and eat as many as four small rodents in a night. They prefer to hunt from the air over open country and avoid pursuing their prey in densely wooded areas. Quite often they will swallow their prey whole and any parts of the body that they cannot digest will be formed into pellets that they later regurgitate. They are crepuscular, which means they are at their most active and go hunting for food mainly around dusk and dawn. They can start breeding in their first year and the breeding season for these owls starts in the late winter or early spring, as soon as food becomes plentiful. As long as there is a good supply of prey they can produce two broods in a year. In captivity barn owls can live as long as twenty years, but in the wild they have a high mortality rate often dying in the first couple of years due to predation and accidents. Unfortunately, many barn owls die due to human activity and they also fall victim to the domestic animals kept by us such as cats and dogs.
So why have barn owls become an endangered species in Britain? According to several surveys conducted between the 1930s and the late 1990s the numbers of these birds have dropped by around two thirds, with the population dipping as low as 4,000 breeding pairs at one point. Due to a concerted conservation effort the numbers have risen again to around 8,000 breeding pairs and hopefully the population will continue to grow. But what caused this cataclysmic drop in numbers? Like a lot of the world’s endangered species, the barn owl has suffered from a loss of habitat leading to scarcity of prey and a loss of suitable nesting sites. They have co-existed with man in Britain since prehistoric times and have relied on our barns and farm buildings for nesting and roosting sites. But the human population of the UK has grown rapidly over the last half century, with towns and cities sprawling ever larger and more and more people moving into the countryside. Many of the old barns and agricultural buildings that the barn owls are dependent on are prime targets for developers and many old barns have been converted into modern residences with no room for roosting owls. Agricultural practices have also changed greatly, with many small farms with traditional field patterns and hedgerows being amalgamated into large intensive farms that have huge fields that are easy to harvest by modern machinery, which has led to a devastating loss of habitat for many native British species. Barn owls also use hollow trees for nesting and many of these have also being cleared.
So what conservation methods are being used in the effort to build barn owl numbers? Increasing suitable habitat across farmland has been very important, as approximately 80% of the UK is still given over to agriculture. Around eighty farms in the UK have signed up with an organisation call Conservation Grade which promotes farming practices that are sustainable for the countryside and native wildlife. If they sign up, farmers are required to ensure that a minimum of 2% of their farmland is given over to creating habitat that encourages native plant, animal, bird and insect species. This could be in the form of suitable grassland, and many of the farmers create edges along the sides of their fields that are left wild or restored with native vegetation and plant species. Preserving and restoring hedgerows is also important, as many small animals and insects live and breed in them, including many of the small rodents that the barn owls prey on, and farmers are also encouraged to put up nest boxes in suitable places to make up for the loss of their traditional nesting sites. In return for these conservation efforts, the participating farmers are paid a premium for their produce. There are also several charities dedicated to conserving barn owls, such as the Barn Owl Trust, that work very hard on research, countryside surveys and preserving the habitats of these amazing birds.
In our crowded modern world, it is becoming increasingly difficult to balance the needs of our human population and the natural world. But losing any species to extinction is an irreparable loss and losing a top predator like the barn owl would be a tragedy for mankind as well as hugely damaging to our countryside. Losing a top predator takes an important link out of the food chain, creating a huge imbalance in the ecosystem that can have huge ramifications for all the other species living there. So let us hope that the British barn owl population continues to grow and thrive so that these magnificent birds of prey can be seen hunting across our farmlands during the hours of dusk and dawn for many years to come.