African Birds

The inclusion of buffer zones in the establishment of protected areas has become a common practice in conservation. However, little is known about the efficiency of these buffer zones around national parks in Liberia and most parts of Africa. Sapo National Park (SNP) is the only national park in Liberia and contains the second-largest area of primary rainforest in West Africa. This study assessed the role of the buffer zone in the conservation of birds of SNP. Birds were surveyed using Distance Sampling with line transects. A total of 183 bird species belonging to 55 families were recorded. Sixteen species of global conservation concern were recorded in both SNP and the buffer zone including the ‘Endangered’ Gola Malimbe Malimbus ballmanni and ‘Vulnerable’ Yellowbearded Greenbul Criniger Olivaceous. The overall mean density of species and Pielou’s evenness index were significantly higher in the Park than the buffer zone, while species richness and diversity were higher in the buffer zone compared to the Park. The high density and evenness of birds in the Park may be attributed to the intactness and homogeneity of the forest inside the Park. On the other hand, the high species richness and slightly higher diversity in the buffer could be attributed to the heterogeneity in the buffer habitats and the observed availability of food resources (several fruiting trees and farmlands) in the buffer zone as compared to the Park during the time of this study. The presence of 16 bird species of global conservation concern and other birds in both SNP and its buffer zone suggests the conservation importance of not only the Park but also the buffer zone in the conservation of these species. Thus, to effectively conserve biodiversity in SNP, conservation planning and active management efforts should explicitly include a well-defined buffer zone around the Park.

A detailed understanding of species' responses to global climate change provides an informative baseline for designing conservation strategies to optimize protection of biodiversity. However, such information is either limited or not available for many tropical species, making it difficult to incorporate climate change into conservation planning for most tropical species. Here, we used correlative ecological niche models to assess potential distributional responses of 3 range-restricted West African birds, Timneh Parrot (Pscittacus erithracus timneh), Ballman's Malimbe (Malimbus ballmanni), and White-necked Rockfowl (Picathartes gymnocephalus), to global climate change. We used primary biodiversity occurrence records for each species obtained from the Global Biodiversity Information Facility, eBird, and VertNet; for environmental data, we used climatic variables for the present and future, the latter characterized by 2 IPCC representative concentration pathways (4.5, 8.5) future emissions scenarios and 27 general circulation models for a 2050 time horizon. We found broad present-day potential distributions with respect to climate for all 3 species. Future potential distributions for Ballman's Malimbe and White-necked Rockfowl tended to be stable and closely similar to their present-day distributions; by contrast, we found marked climate change-driven potential range loss across the range of Timneh Parrot. Our results suggest that impacts of climate change on the present distributions of West African birds will in some cases be minimal, but that individual species may respond differently to future conditions. Thus, to optimize conservation of these species, and of bird diversity in general, we recommend that regional-to-national species conservation action plans incorporate climate change adaptation strategies for individual species; ecological niche models could provide an informative base-line information for this planning and prioritization. Effets des changements climatiques sur le potentiel de répartition de trois espèces d'oiseaux d'Afrique de l'Ouest ayant une aire de répartition restreinte RÉSUMÉ Une compréhension détaillée des réponses des espèces aux changements climatiques fournit une base de référence informative pour concevoir des stratégies de conservation afin d'optimiser la protection de la biodiversité. Cependant, ces informations sont soit limitées, soit non disponibles pour plusieurs espèces tropicales, rendant difficile d'incorporer les changements climatiques dans la planification de la conservation pour la plupart des espèces tropicales. Nous avons utilisé des modèles de niche écologique corrélés pour évaluer les réponses potentielles de répartition face aux changements climatiques de trois oiseaux d'Afrique de l'Ouest à l'aire de répartition restreinte, soit Pscittacus erithracus timneh, Malimbus ballmanni et Picathartes gymnocephalus. Pour chaque espèce, nous avons utilisé des mentions de biodiversité primaire provenant du Système mondial d'informations sur la biodiversité, d'eBird et de VertNet; pour les données environnementales, nous avons utilisé des variables climatiques actuelles et futures, ces dernières étant caractérisées par deux profils représentatifs d'évolution de concentration (4.5, 8.5) du GIEC et 27 modèles de circulation générale jusqu'à l'horizon 2050. Nous avons trouvé de grandes répartitions potentielles actuelles relativement au climat pour les trois espèces. Les répartitions potentielles futures pour M. ballmanni et P. gymnocephalus avaient tendance à être stables et très similaires aux répartitions actuelles; au contraire, nous avons constaté une diminution potentielle marquée de l'aire de répartition de P. erithracus timneh due aux changements climatiques. Nos résultats suggèrent que les impacts des changements climatiques sur les répartitions actuelles d'oiseaux d'Afrique de l'Ouest seront dans certains cas minimaux, mais que des espèces pourraient répondre différemment aux conditions futures. Ainsi, afin d'optimiser la conservation de ces espèces et de la diversité aviaire en général, nous recommandons que les plans d'action régionaux et nationaux pour la conservation des espèces incluent des stratégies d'adaptation aux changements climatiques pour des espèces individuelles; les modèles de niche écologique pourraient fournir une base de référence informative pour cette planification et l'établissement des priorités.

A detailed inventory is provided of the avifauna of montane forests in two highland areas in the Eastern Arc Mountains of Tanzania representing adjacent fault blocks separated by the Great Ruaha River Basin. For the first time detailed survey data is provided for all major montane forests south and north of this potential dispersal barrier. Detailed distribution data and novel interpretations of species boundaries make it possible to tell apart the relative roles of the barrier and of environmental factors affecting the local persistence of populations. Highland forests on opposite sides of the Great Ruaha
Basin had virtually identical faunas of resident montane forest birds, and many range-restricted species had dense populations in both highlands. Unlike this, species depending on foothill forest, at least for part of the year, had small or no populations north of the Great Ruaha River. Apparently, the Rubeho area represents sink habitat for many low- or mid-elevation species, and although there are no dispersal barriers in the foothill zone, it is suggested that this zone represents sink habitat which provides little
gene flow. Sharp species replacements, although sometimes corresponding to physical barriers, may be secondary phenomena arising as a consequence of population expansion and incompatibility of the involved populations. Physical breaks in the landscape may enhance speciation if they are large enough, but the overwhelming tendency to search for barriers as explanation of speciation may often lead to neglect of other environmental variables that enhance local population persistence. Detailed molecular studies, with nested clade analysis, may greatly improve our understanding of the process of biological diversification within this biodiversity hotspot, and this may guide our decisions about
where to focus conservation efforts.

An urgent question in biodiversity conservation is the extent to which priority areas for one well-known indicator group, like birds, “capture” species within other groups. The first tests of this question have indicated that capture is high. BirdLife International’s “Important Bird Areas” (IBAs) work on this assumption. We test this for East African IBAs using databases on the distribution of all Afrotropical birds, mammals, snakes and amphibians, compiled at the Zoological Museum of the University of Copenhagen and mapped on a 1-degree grid in the software WORLDMAP. We assess how well the IBAs capture terrestrial vertebrate species in the region, and find that absolute capture is high. Moreover, capture of regionally endemic and threatened species is also very high. We indicate those few important species and areas not covered by IBAs. However, the IBAs do not generally capture other groups significantly better than do random selection sets of areas covering the same extent. Further, systematically selected near-minimum sets of areas can capture more species in considerably less area. Nevertheless, these near-minimum sets take into account neither ecological processes (in particular, avian migration) nor actual land-use patterns. As data become available to incorporate these factors and other taxa into quantitative priority-setting techniques, IBAs may be able to be planned with added area-efficiency. For now, though, we suggest that IBAs are not only very effective on-the-ground priorities for the conservation of birds but they also represent the majority of other terrestrial vertebrate diversity.

During ornithological surveys and data-gathering for ecological studies of African forest birds, a new and highly distinct perdicine bird was discovered on 3 July 1991. This happened in so-far unexplored montane rainforest fragments in the Udzungwa Mountains in south-western Tanzania. The Udzungwa mountains represents the southernmost block of the "Eastern Arc Mountain", defined by Lovett (1990) as the chain of crystalline mountains under the direct climatic influence of the Indian Ocean. These mountains are now known for their high level of endemism in several groups of plants and animals. This paper describes the characteristics of this new species.

An urgent question in biodiversity conservation is the extent to which priority areas for one well-known indicator group, like birds,“capture” species within other groups. The first tests of this question have indicated that capture is high. BirdLife International's “Important Bird Areas”(IBAs) work on this assumption. We test this for East African IBAs using databases on the distribution of all Afrotropical birds, mammals, snakes and amphibians, compiled at the Zoological Museum of the University of Copenhagen and mapped on a 1-degree grid in ...