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"This handbook provides a comprehensive overview of the history, theory and current practices of rewilding. Rewilding offers a transformational paradigm shift in conservation thinking, and as such is increasingly of interest to academics, policymakers and practitioners. However, as a rapidly emerging area of conservation, the term has often been defined and used in a variety of different ways (both temporally and spatially). There is, therefore, the need for a comprehensive assessment of this field, and the Routledge Handbook of Rewilding fills this lacuna. The handbook is organized into four sections to reflect key areas of rewilding theory, practice and debate: the evolution of rewilding, theoretical and practical underpinnings, applications and impacts, and the ethics and philosophy of rewilding. Drawing on a range of international case studies the handbook addresses many of the key issues, including land acquisition and longer-term planning, transitioning from restoration (human-led, nature enabled) to rewilding (nature-led, human enabled), and the role of political and social transformational change. Led by an editorial team who have extensive experience researching and practicing rewilding, this handbook is essential reading for students, academics and practitioners interested in rewilding, ecological restoration, natural resource management and conservation"--

Context
The increase in density of large tree species, Vachellia robusta and V. tortilis, in the Serengeti Ecosystem of Tanzania has resulted in a decline of small tree species Senegalia senegal, V. hockii, Commiphora spp. This change has occurred since the late 1970s, a consequence of an increase in wildebeest following the extirpation of rinderpest, which reduced the dry grass fuel for fires, resulting in low fire frequencies. Change in tree species raises the question of whether there are indirect consequences for the avifauna that depend on the large trees for food and nesting.

Aims
To determine how an increase in large mammals could influence diversity and distribution of avifauna communities in the Serengeti ecosystem woodlands.

Methods
Data used to estimate changes in density of large and small trees were measured by Point Centre Quarter (PCQ). Bird species were recorded in 19 small-tree sites and 18 large-tree sites in the Serengeti National Park. Richness of bird guilds was calculated in the two habitat complexes (small and large trees), and the 'rarefaction' method was used to assess the difference in richness in habitats of the study area. Mean abundance for each species was calculated over the total number of sites for each habitat and compared using the Wilcoxon Rank Sum test to examine how the abundance of avifauna changes with each habitat type.

Key results
There was an increase in the density of large trees in some areas in which they have replaced the original small trees. Such changes have resulted in greater richness of hole nesters and bark feeders, and a greater abundance of large-hole nesters and gleaner bird species.

Conclusions
Because the increase in tree density was caused by an increase in large mammals, we conclude that this increasing mammal population is indirectly increasing richness and abundance of birds using the trees.

Implications
Understanding the influence of large mammal populations on bird distributions has important conservation implications because the Serengeti ecosystem is classified as an important, endemic bird area.

Vultures provide critical ecosystem services, yet populations of many species have collapsed worldwide. We present the first estimates of a 30-year Pan-African vulture decline, confirming that declines have occurred on a scale broadly comparable with those seen in Asia, where the ecological, economic, and human costs are already documented. Populations of eight species we assessed had declined by an average of 62%; seven had declined at a rate of 80% or more over three generations. Of these, at least six appear to qualify for uplisting to Critically Endangered. Africa's vultures are facing a range of specific threats, the most significant of which are poisoning and trade in traditional medicines, which together accounted for 90% of reported deaths. We recommend that national governments urgently enact and enforce legislation to strictly regulate the sale and use of pesticides and poisons, to eliminate the illegal trade in vulture body parts, as food or medicine, and to minimize mortality caused by power lines and wind turbines.

Vultures provide critical ecosystem services, yet populations of many species have collapsed worldwide. We present the first estimates of a 30-year Pan- African vulture decline, confirming that declines have occurred on a scale broadly comparable with those seen in Asia, where the ecological, economic, and human costs are already documented. Populations of eight species we assessed had declined by an average of 62%; seven had declined at a rate of 80% or more over three generations. Of these, at least six appear to qualify for uplisting to Critically Endangered. Africa's vultures are facing a range of specific threats, the most significant of which are poisoning and trade in traditional medicines, which together accounted for 90% of reported deaths. We recommend that national governments urgently enact and enforce legislation to strictly regulate the sale and use of pesticides and poisons, to eliminate the illegal trade in vulture body parts, as food or medicine, and to minimize mortality caused by power lines and wind turbines. ; Publisher PDF ; Peer reviewed