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SummaryClimate change is predicted to have serious impacts on the conservation status of numerous species of birds, particularly low-density, range-restricted species occupying narrow habitats. One such species is the globally "Endangered" Sokoke Scops Owl Otus ireneae that currently survives in just two or three small pockets of forest in coastal Kenya and north-eastern Tanzania. We assessed the potential impact of changes in future climate on this species using predictive niche modelling. Distributional data were obtained from various published and unpublished sources, and field surveys. Maximum Entropy (Maxent) was used to model the current distribution of Sokoke Scops Owl. A general circulation model was used to predict the distribution of this species in 2080. This scenario predicts a southward shift in the future distribution of this species in Kenya and a complete disappearance from the Usambara mountains in Tanzania, with a concomitant 64% reduction in areas of high environmental suitability. Considering the isolated nature of the forest fragments in which this owl survives and the sea of inhospitable human-modified habitat which surrounds these fragments, the future conservation prospects of this species are bleak. Close monitoring of the species is strongly recommended and potential conservation interventions are discussed.

High human population growth and rapid urbanisation, particularly in Africa, have led to an increased interest in the impacts of this land-use change on bird communities. The African Bird Atlas Project, where species presence lists are collected in pentads, is a valuable source of data with which to explore the extent of these impacts. Here, for the first-time, we test for differences in species richness patterns across 50 matched pentad pairs from sub-Saharan Africa classified as either urban (or semi-urban) and rural. We found that species richness was lowest in pentads classified as urban (mean ± SD: 132 ± 59 species), compared with rural (172 ± 54). However, species richness was similar, compared with rural pentads, when levels of urbanisation were maintained at intermediate levels (semi-urban: 141 ± 69). Surprisingly, we found no significant differences in functional diversity measures between any land-use categories. Across most major dietary guilds (carnivores, herbivores, insectivores, granivores) species richness was lower in urbanised pentads and species were often small. However, the overall biomass of these guilds was similar between urbanised and non-urbanised areas, indicating the presence of common urban exploiter species. This resulted in no differences in functional diversity overall. Pollinators and piscivores showed little difference in metrics between rural and urban pentads. According to a model of the functional traits we consider, an African urban exploiter species is best described by being a scavenger, and less likely to be a habitat specialist, but fill a variety of niches. The urban spatial planning implications are that rare and range-restricted species in proximity to cities, as well as large bird species, will require particular attention and conservation measures as African cities continue to expand. Species richness could be maintained with intermediate levels of urban infrastructure development. Les zones urbaniséessont moins riches en espèces mais conservent une diversité fonctionnelle: un aperçu du projet d'Atlas des oiseaux d'Afrique La forte croissance de la population humaine et l'urbanisation rapide, plus particulièrement en Afrique, ont suscité un intérêt accru sur les impacts de ce changement d'utilisation des terres sur les communautés aviaires. Le projet d'Atlas des oiseaux d'Afrique, qui collecte les données relatives à la présence des espèces au travers de pentades (groupe de cinq unités), est un source précieuse de données permettant d'explorer l'étendue de ces impacts. Au travers de cet article, et pour la première fois, nous testons les différences en termes de richesse d'espèces, au travers de modèles basés sur 50 paires de pentades appariées d'Afrique sub-saharienne et classées comme urbaines (ou semi-urbains) ou rurales. Nous avons estimé que la richesse en espèces était la plus faible dans des pentades de catégorie urbaine (moyenne ± σ: 132 ± 59 espèces) par comparaison aux groupes ruraux (172 ± 54 espèces). Néanmoins, il a été constaté que la richesse en espèce...

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Although studies have explored how habitat structure and disturbance affect arthropod communities, few have explicitly tested the effects of both structure and disturbance level across trophic levels and phyla. We present here the results of a study conducted in the Arabuko‐Sokoke Forest (ASF) of coastal Kenya, in which abundance of arthropods and one of their avian predators, the East Coast Akalat Sheppardia gunning sokokensis was compared in relatively undisturbed habitat (outside elephant roaming areas) and in disturbed habitat (inside elephant roaming areas). Vegetation structure in both areas was measured using several metrics, including leaf litter depth, understory vegetation density, animal disturbance and fallen log counts. Leaf litter and coleopteran abundance were higher outside the elephant roaming areas, whereas understory visibility, animal disturbance and dipteran diversity were much higher inside the elephant areas. Species composition of several arthropod taxa (e.g. Hymenoptera, Coleoptera, Diptera, Hemiptera and Araneae) was also influenced by degree of disturbance, whereas akalat abundance was inversely related to understory visibility. Our results suggest that differences in species sensitivity to habitat disturbance and vegetation structure across trophic levels should be incorporated into the management and conservation of rare and endangered species.

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A methodology for rapidly assessing the vulnerability of waterbirds to disturbance was tested at Sabaki estuary, Kenya. Three variables were employed to measure the responses of 15 species: (1) bird density, (2) minimum distance of birds from a stationary disturbance and (3) recovery times following a moving disturbance. Spatial response metrics (1) and (2) were regressed against expected species densities (in the absence of disturbance). Normalised mean residuals then described species-specific deviations from the average spatial response to disturbance. A hypothetical model was constructed, whereby species were placed on a spatial response gradient and overlaid by the recovery metric (3). Greater Flamingo Phoenicopterus roseus, Lesser Flamingo Phoeniconaias minor, African Spoonbill Platalea alba and Terek Sandpiper Xenus cinereus exhibited the strongest avoidance responses. The two spatial metrics (1 and 2) achieved concordance for 73% of species, and all three metrics gave similar results for six of seven species at the extremes of the spatial response gradient. Non-concordance between response metrics is likely an effect of life-history traits (e.g. territoriality). Our results support the use of relative spatial response metrics (1 and 2) for robust and rapid identification of waterbird species that are most responsive and, by virtue, vulnerable to the effects of disturbance on tropical estuaries.

a b s t r a c tConservation of threatened or endangered species relies critically on accurate population counts over time. In practice, many population censuses are conducted by non-governmental organizations or volunteer citizen scientists who are constrained by fiscal and temporal resources. Less than optimal sampling regimens (characterized by infrequent and/or irregular schedules) for conducting population censuses can result in woefully misleading population estimates -and thus have dire consequences for management and conservation. We illustrate this using an East African case study in which 14 years of bird data was collected in the Arabuko-Sokoke Forest in coastal Kenya. We first estimate life history parameters in a discrete matrix model. Desiring a data collection protocol which would lessen observation error and lend to a deeper understanding of population projections and dynamics of a threatened species, we carry out mathematical and statistical modeling efforts with an adaptation of a Leslie model for simulated population estimates stemming from different population sampling schemes. We illustrate how resource managers might take a strategic approach, using simple quantitative models, to develop an optimal sampling scheme that considers important species traits, such as breeding season, and balances the tradeoff between resources and accuracy.