Anyone who has watched birds in their garden for a number of

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1 Cottage garden birds Our cottage gardens provide a haven for many species of birds, some which are faring well and others which have experienced recent declines. Tim Harrison of the British Trust for Ornithology (BTO) reviews the recent ups and downs, and highlights what to look forward to this spring. Anyone who has watched birds in their garden for a number of years could tell stories of visitors that were once present but have now disappeared, and of new birds that have come to grace their bird tables and feeders. Indeed, our garden bird communities are tremendously fluid, influenced by a range of factors including land use both at home and abroad, and by changes in our climate. Gardens encompass a huge area of the country - greater than that of national and RSPB nature reserves combined - but remain relatively understudied. Fortunately, however, the BTO has been able to find out more with the help of the public through the year-round BTO Garden BirdWatch survey. Amongst the recent garden success stories, two species particularly stand out - not least because of their striking physical presence. Sweeping vibrant colours into an increasing number of gardens has been the goldfinch, with its jet black wing markings laced with gold, rich fawncoloured back and breast, and blood-red face as if to suggest embarrassment at its own splendour. Goldfinches have taken particularly to sunflower hearts and nyjer seed during recent years as these foods have been provided more frequently by householders. However, away from feeders, the seeds of numerous species of the Asteraceae or Compositae family (asters, daisies, or sunflowers) are also taken, and flocks will feed busily on alder (Alnus spp.) and pine (Pinus spp.) during the winter months.

2 The second major success story in gardens has been a divisive presence - the woodpigeon. This corpulent species is, at closer inspection, a rather elegant bird with soft, diffuse shades of pink and grey and smart white collar. However, its voracious appetite has seen garden bird food disappear at a tremendous rate, with concern raised by householders that smaller birds are not getting a look in. Since 1995, when the BTO s Garden BirdWatch commenced, the percentage of gardens occupied by woodpigeons has increased from 48% to 82% last year. To a lesser extent, readers of The Cottage Gardener are also likely to have witnessed increases in the numbers of great spotted woodpecker, long-tailed tit, bullfinch and blackcap in recent years. But even in a cottage garden oases a number of different species have recently felt the pinch. House sparrow numbers have experienced a highprofile decline, plummeting from 83% of gardens occupied in 1995 to 64% of gardens in This decline has been the focus of much scientific research with explanations including a loss of nesting and forging habitats, predation by cats and a paucity of invertebrate food with which to feed young. Numbers of starlings have also declined sharply during recent decades, both in gardens and in the wider countryside. This charismatic visitor is loved by many gardeners for its vast array of chattering and whistles and its glossy plumage, but resented by some for its apparent bullying of other birds at feeders and considerable collective appetite. However, given that the decline of this species may be explained by reduced survival rates of young birds, every scrap of food that you provide, and they demolish, is perhaps an important step towards their survival. Moreover, a favoured food of starlings is leatherjackets which can decimate a lawn, so perhaps this species should be coveted as a gardener s friend! Gazing out of the window or working busily in the garden, householders can also be treated to the sight of greenfinches - with their rich contact

3 calls that form dancing triplets across the sky, and its slurred notes that emanate playfully from the tree tops. In recent years, however, its numbers have tumbled because of the disease trichomonosis. The disease is spread through the saliva of an infected individual coming into contact with that of a healthy bird, so regularly cleaning bird feeders and bird baths is likely to reduce the risk of disease transmission. BTO Garden BirdWatch can provide more advice - please see contact details below. Springtime garden birdwatching Spring is a great time to get out and about in the garden, to feel the sunshine gently on your back and to enjoy all of the birds that come to visit. The fresh air is invigorated by the songs of many familiar species during spring, with tuneful males seeking to secure a breeding territory. For many species, gardens represent a large proportion of their breeding habitat and cottage gardens are likely to be a particular hotspot. As gardeners, there is much that we can do to try to help our nesting companions. Nest material Many cottage gardeners will be fortunate enough to have a blue tit or great tit nesting on their patch this spring. Both species build their nests predominantly of moss, with blue tits often lining the top of their nest with feathers and great tits with fur or wool. Furry nests may contain material from various different mammals, such as deer, horse, cat and dog, and can, to us, form a pungent layer! Woolly nests can be multicoloured, with wool ranging from white, to purple, and even to fluorescent colours. Mossy areas will help blue tits and great tits to build the main bulk of their nests, and a top tip is to provide fur from pet combings, and nesting wool in accessible places to help these birds construct a cosy nest lining. Many garden nesters use mud as the main body of their nest or as glue to stick other nest components together. During prolonged dry periods it might be difficult for species such as blackbird, song thrush and house martin to find wet mud for these

4 purposes so try to keep some areas moist to satisfy their needs. Dead leaves can form an important part of the nests of wrens, being interwoven with grass and moss to form impressive domed structures. Also, look out for birds in your herb bed this spring. Species that use the same nest year after year, such as starlings, often use fresh aromatic herbs as a natural antiseptic, helping to reduce the number of bacteria in their nests. Nesting cover for birds Evergreen vegetation, including natives such as holly (Ilex spp.) and yew (Taxus spp.), offers cover that is not provided by deciduous species early in the breeding season. Some introduced conifers are, however, faster growing and will provide cover more quickly. In particular, varieties of cypresses (Cupressaceae family) are suitable for nesting birds, with shorter varieties (e.g. Chamaecyparis lawsoniana Gnome & Chamaecyparis lawsoniana Minima ) attracting species such as dunnock, and taller varieties (e.g. Chamaecyparis lawsoniana Ellwoodii & Chamaecyparis lawsoniana Columnaris ) species such as greenfinch and goldfinch. Deciduous vegetation comes into its own as nesting cover later in the breeding season, with native hedgerows, shrubs and small trees offering a home to multiple species. Fruit trees not only give nesting opportunities, but also their windfall fruit provides food for birds during autumn and winter. Thick, thorny vegetation, including common hawthorn (Crataegus monogyna), berberis and pyracanytha could be particularly helpful in reducing risk of nest predation, for example from cats. Food for nesting birds Almost all species of bird that breed in gardens rely on invertebrates to rear their young, even those that we think of as predominantly seedeaters, such as sparrows and finches. Indeed, despite great temptation to bring them under control, greenflies are a particularly important food for house sparrows to rear their broods successfully. Specific vegetation can also encourage invertebrates to prosper. Moth caterpillars, for example, are an important food source for the young of several species, including

5 blue tit and great tit, and some vegetation supports many more caterpillars than others, some of the best being: oaks (Quercus spp.) supporting at least 130 species, common hazel (Corylus avellana) 72, blackberry (Rubus fruticosus agg.) 61, and bilberry (Vaccinium myrtillus) 55 species. Of course, not all birds glean invertebrates from foliage - some obtain them from beneath the ground. During periods of dry weather soildwelling invertebrates can become difficult to find, but you could help by keeping at least some of your lawn moist. This should enable species such as blackbird and song thrush to find enough invertebrates, including earthworms, to rear their young. Live food supplements, the most popular being mealworms, could also help birds to evade nutritional shortfalls during this critical time. Make your garden birdwatching count! The BTO has only been able to find out this useful information through the simple observations of householders. BTO Garden BirdWatch is the largest year-round survey of garden birds in the world and we would really like your help. For free information please gbw@bto.org, telephone , or write to Garden BirdWatch, BTO, The Nunnery, Thetford, Norfolk, IP24 2PU. This spring the BTO will also be running its Garden Nesting Survey; so if you have birds nesting in your garden and would like to get involved, please contact us using the above details. The Talking Cottage Gardener CGS magazine on cassette tape If you are finding it hard to read the Society's magazine, or know of a member whose eyesight is deteriorating, then do ask to receive a recorded version. We record each issue onto a 90 minute tape which is sent out as soon as possible after publication of the magazine. To ask to be included in the service, or for more information, contact Ann Broscomb on CGS speakers A list of speakers can be found on our NEW LOOK website: