Springwatch British Wildlife: Accompanies the BBC 2 TV series. Stephen Moss
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Название: Springwatch British Wildlife: Accompanies the BBC 2 TV series

Автор: Stephen Moss

Издательство: HarperCollins

Жанр: Природа и животные

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isbn: 9780007494446

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СКАЧАТЬ and Cetti’s warblers are both resident in Britain, so are very vulnerable to hard winters.

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      ©Sean Hunter/FLPA

      ©Ramon Navarro/Minden Pictures/FLPA

      Tawny and little owls are common across much of Britain, though their habits mean they may be hard to see.

      No other group of birds has quite such an air of mystery surrounding it as the owl. They are both everywhere and nowhere: several species are common and widespread throughout most of lowland Britain, yet they are hardly ever seen, and even less well known. As a result, they have given rise to a large body of folklore, sayings and old wives’ tales, most of which are utter nonsense, but a few do have a ring of truth about them.

      Five species of owl breed in Britain: tawny, little, short-eared, long-eared and barn owls, although the barn owl is from a different family and is discussed separately. A sixth species, the snowy owl, did briefly gain a toehold as a British breeding bird during the late 1960s and 1970s, when a few birds travelled south from Scandinavia to take up residence on the Shetland island of Fetlar. A warming climate has since seen snowy owls retreat back northwards to their Arctic home, and the species is now only a very rare visitor to our shores.

      Of all our owls, the tawny owl is both the commonest and most widespread in Britain, found in England and Wales and much of lowland Scotland. But even though there are around 20,000 breeding pairs (about twice as many as its nearest rival, the little owl), this species is hardly ever seen, due to its nocturnal habits.

      Your best chance of catching up with a tawny owl is if you come across one at its daytime roost – you may be alerted to its presence by the noise made by small birds mobbing this predator in their midst. If you do see one, you may be surprised at how large they are, especially on the rare occasions when they take to the wing.

      If tawny owls are hard to see, they are a lot easier to hear, though the famous ‘to-whit, to-whooo’ call is a myth, being a combination of sounds made by the male (hooting) and the female (the shrill ‘kee-wick’). Tawny owls are our most sedentary species, with a tiny territory, so they often hoot during the autumn months – this is the male fending off any of his offspring that might otherwise take over his precious territory. They hunt by night, floating through their woodland habitat and catching voles and other small rodents.

      The little owl is very different in both appearance and habits from its larger cousin. Only about the size of a starling, our smallest owl is also far more active during the day than either tawny or barn owls. You are most likely to come across one in lowland farmland in southern Britain, either perched on a barn roof or, most likely, in the branches of an oak tree. They hunt a wide range of prey, including worms, beetles and small birds and mammals.

      Unlike our other four owl species, the little owl is not strictly native to Britain, having been brought here in the late nineteenth century from continental Europe, to adorn the parkland estates of stately homes. But whereas other introduced species such as the grey squirrel and ruddy duck have wrought havoc with our native wildlife, the little owl’s presence here doesn’t appear to cause much harm, and it is now generally regarded as a true Brit.

      Two other species of owl, short-eared and long-eared, are seen much less often. Of the two, the short-eared, which often flies and hunts by day across large areas of heather moorland, is certainly the more commonly encountered. However, the male’s incredible display flight, in which he rises up into the sky and then falls towards earth clapping his wings together beneath him, is a rare sight. In winter, birds from Scandinavia join our native population of short-eared owls, but, in recent years, these have become less frequent visitors.

      The long-eared owl must surely take the prize for the least-known and least-sighted regular British breeding bird. It is strictly nocturnal, and frequently nests in dense coniferous forests, where birders rarely visit. Often the only clue to its presence is the strange sound made by the young birds, which sounds like a creaking hinge on a gate. In recent years, the already small population of long-eared owls has declined still further, and there must now be fears for the future survival of this mysterious and beautiful bird.

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      ©Jules Cox/FLPA

      ©Sean Hunter/FLPA

      Short-eared and long-eared owls have very different lifestyles: short-eared hunts by day over moors; long-eared hunts by night in dense woods.

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      ©Phil McLean/FLPA

      The barn owl is very vulnerable to snowy weather as the snow covers up its food supply of voles and mice.

      Despite its obvious affinity with our other British owls, the barn owl is in fact from a separate, though related, family. It is by far the most cosmopolitan and widespread of all the world’s owls, being found in six of the world’s seven continents (the exception being, of course, Antarctica), and on many remote offshore islands.

      Here, in Britain, the barn owl is well known as a bird of open, mainly arable farmland, where it hunts at dawn and dusk. Barn owls float over the ground on soft, virtually silent wings, thanks to a special adaptation, which makes their wing feathers almost down-like in their quality, muffling any sound. Unfortunately, this advantage is also the barn owl’s Achilles heel, as its plumage gets waterlogged very easily, which means it cannot hunt when it is raining. During prolonged periods of wet weather, this can be disastrous, especially when the owls have hungry chicks in the nest. Often they will abandon their first breeding attempt and try again later in the season, if and when the weather improves.

      Harsh winter weather can also be very bad for barn owls: prolonged periods with snow on the ground means that their food supply of voles and other small rodents are unavailable, and many starve to death during cold winters. The barn owl relies heavily on voles for food. Their populations rise and fall in cycles, resulting in ‘good vole years’, which lead to a boom in barn owls, but also ‘bad vole years’, when barn owl numbers may plummet, especially if they coincide with a wet summer or icy winter.

      Like many predators at the top of the food chain, including the sparrowhawk and peregrine, barn owls were also badly hit by the indiscriminate use of agricultural pesticides such as DDT in the post-war farming boom. The final problem these beautiful birds face is the danger from traffic: they fly so low when hunting that they are especially vulnerable to being hit by cars or lorries, and their corpses can often be seen along major roads, especially in their stronghold of EastAnglia.

      With all these hazards, it might seem surprising that barn owls are actually doing reasonably well at the moment. This is partly because farmers and conservationists have joined forces to put up nest boxes in their barns and other farm buildings, which the barn owls take to readily.

      Barn owls have a unique breeding strategy, to help them cope with the unpredictability of the weather and their intermittent food supply. Since they cannot predict how much food they will be able to bring back for their chicks, they begin incubating as soon as the first egg is laid, which means that the youngsters vary considerably in size and strength. In a good year, as many as six chicks may be raised to fledging, but in a bad year all but one may die. In a grisly twist to this, the oldest chicks СКАЧАТЬ