Abstract Habitat loss is widely acknowledged as a key driver of global biodiversity decline. However, whether biodiversity loss occurs in response to reductions in habitat amount versus reductions in connectivity in fragmented landscapes is debated. A challenge in resolving this issue is that measures of the amount of native woody vegetation cover and those calculated for structural connectivity are often highly correlated. Using multi-season detection-occupancy models we address the question: After accounting for the effects of native woody vegetation cover, what is the contribution of structural connectivity to site occupancy, site persistence and site colonization by birds? In this context, structural connectivity corresponded to the configuration of vegetation cover in the landscape surrounding our sites. We constructed multi-season detection-occupancy models for 44 individual bird species based on long-term field surveys in the temperate woodlands of eastern Australia. We found responses to vegetation amount were far more prevalent than responses to structural connectivity (35 vs 6 species). The range of responses by different species to vegetation amount, to structural connectivity, or to both, suggests that these elements have different effects on the processes of occupancy, persistence and colonization. The predominance of vegetation amount effects in our study, particularly the positive effects for a range of species of conservation concern, suggests the critical importance of both conserving existing areas of native vegetation cover and increasing the amount of that cover. At least for birds, efforts to physically connect particular patches may have relatively less benefit compared to programs to boost overall vegetation cover.

中文翻译：

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栖息地数量与连通性：鸟类反应的实证研究

摘要 栖息地丧失被广泛认为是全球生物多样性下降的关键驱动因素。然而，生物多样性的丧失是否是由于栖息地数量的减少与支离破碎的景观中连通性的减少而发生的，这是有争议的。解决这个问题的一个挑战是，原生木本植被覆盖量的测量值与结构连通性计算值通常高度相关。我们使用多季节检测-占用模型解决了这个问题：在考虑了本地木本植被覆盖的影响后，结构连通性对站点占用、站点持久性和鸟类定植的贡献是什么？在这种情况下，结构连通性对应于我们场地周围景观中植被覆盖的配置。我们基于澳大利亚东部温带林地的长期实地调查，为 44 种鸟类构建了多季节检测-占用模型。我们发现对植被数量的反应比对结构连通性的反应更为普遍（35 对 6 种）。不同物种对植被数量、结构连通性或两者的反应范围表明，这些因素对居住、持久和殖民过程有不同的影响。在我们的研究中，植被数量效应的优势，特别是对一系列保护关注物种的积极影响，表明保护现有本地植被覆盖区域和增加覆盖数量至关重要。至少对于鸟类来说，