Smith Paul G R
Environmental Policy and Programs Branch, Ministry of Agriculture, Food and Rural Affairs, 1 Stone Road West, 3rd floor, Guelph, Ontario, Canada N1G 4Y2.
Environ Manage. 2007 Mar;39(3):338-52. doi: 10.1007/s00267-005-0028-2. Epub 2007 Jan 2.
Characteristics of urban natural areas and surrounding landscapes were identified that best explain winter bird use for 28 urban natural areas in southern Ontario, Canada. The research confirms for winter birds the importance of area (size) and natural vegetation, rather than managed, horticultural parkland, within urban natural areas as well as percent urban land use and natural habitat in surrounding landscapes. Alien bird density and percent ground feeding species increased with percent surrounding urban land use. Higher percent forest cover was associated with higher percentages of forest, bark feeding, small (<20 g) and insectivorous species. Natural area size (ha) was related to higher species richness, lower evenness and higher percentages of insectivorous, forest interior, area-sensitive, upper canopy, bark feeding, and non-resident species. Higher number of habitat types within natural areas and percent natural habitat in surrounding landscapes were also associated with higher species richness. Common, resident bird species dominated small areas (<6.5 ha), while less common non-residents increased with area, indicative of a nested distribution. Areas at least 6.5 ha and more generally >20 ha start to support some area-sensitive species. Areas similar to rural forests had >25% insectivores, >25% forest interior species, >25% small species, and <5% alien species. Indicator species separated urban natural areas from rural habitats and ordination placed urban natural areas along a gradient between urban development and undisturbed, rural forests. More attention is needed on issues of winter bird conservation in urban landscapes.
研究确定了加拿大安大略省南部28个城市自然区域的城市自然区域及周边景观的特征，这些特征最能解释冬季鸟类对它们的利用情况。该研究证实，对于冬季鸟类来说，城市自然区域内的面积（大小）和自然植被而非人工管理的园艺绿地，以及周边景观中的城市土地利用百分比和自然栖息地百分比至关重要。外来鸟类密度和地面取食物种百分比随周边城市土地利用百分比的增加而增加。较高的森林覆盖率与森林、树皮取食、小型（<20克）和食虫物种的较高百分比相关。自然区域面积（公顷）与较高的物种丰富度、较低的均匀度以及食虫、森林内部、对面积敏感、树冠层上部、树皮取食和非本地物种的较高百分比相关。自然区域内栖息地类型的数量较多以及周边景观中自然栖息地的百分比也与较高的物种丰富度相关。常见的留鸟物种在小面积区域（<6.5公顷）占主导，而不太常见的非本地物种则随面积增加，这表明存在嵌套分布。至少6.5公顷且更普遍大于20公顷的区域开始支持一些对面积敏感的物种。与农村森林相似的区域有>25%的食虫动物、>25%的森林内部物种、>25% 的小型物种和<5%的外来物种。指示物种将城市自然区域与农村栖息地区分开来，排序将城市自然区域置于城市发展和未受干扰的农村森林之间的梯度上。城市景观中的冬季鸟类保护问题需要更多关注。
