Fishing of Ceryle rudis Linnaeus, 1758 (Alcedinidae: Coraciiformes, Aves) in Lake Tanganyika

peer reviewedTanganyika Lake is frequented by many fish-eating birds, especially kingfishers. Our research has focused in particular on Ceryle rudis Linné, 1758, pied kingfisher. This study, conducted over a period of two months, from June 21 to July 19 and from August 19 to September 16, 2002, aims to analyze the fishery of pied kingfisher, considering fishing time during the day, before and afternoon. This bird was fishing from a perch or a hovering position. This regularly observed behavior allows the bird to fish in the pelagic water, which is uncommon in other species of kingfishers. This part distinguishes direct dives carried out from a perch and dives performed after a hovering position. Results show that, on a total of 583 dives, 324 or 55,5% were dives from perches while the rest were made from a hovering position. We found that Ceryle rudis is very active in fishing until midday and it is less so in the afternoon. The average number of fish eaten per day per bird was 9,3

Predicting range shifts of African apes under global change scenarios

Aim: Modelling African great ape distribution has until now focused on current or past conditions, while future scenarios remain scarcely explored. Using an ensemble forecasting approach, we predicted changes in taxon-specific distribution under future scenarios of climate, land use and human populations for (1) areas outside protected areas (PAs) only (assuming complete management effectiveness of PAs), (2) the entire study region and (3) interspecies range overlap. Location: Tropical Africa. Methods: We compiled occurrence data (n = 5,203) on African apes from the IUCN A.P.E.S. database and extracted relevant climate-, habitat- and human-related predictors representing current and future (2050) conditions to predict taxon-specific range change under a best- and a worst-case scenario, using ensemble forecasting. Results: The predictive performance of the models varied across taxa. Synergistic interactions between predictors are shaping African ape distribution, particularly human-related variables. On average across taxa, a range decline of 50% is expected outside PAs under the best scenario if no dispersal occurs (61% in worst scenario). Otherwise, an 85% range reduction is predicted to occur across study regions (94% worst). However, range gains are predicted outside PAs if dispersal occurs (52% best, 21% worst), with a slight increase in gains expected across study regions (66% best, 24% worst). Moreover, more than half of range losses and gains are predicted to occur outside PAs where interspecific ranges overlap. Main Conclusions: Massive range decline is expected by 2050, but range gain is uncertain as African apes will not be able to occupy these new areas immediately due to their limited dispersal capacity, migration lag and ecological constraints. Given that most future range changes are predicted outside PAs, Africa\u27s current PA network is likely to be insufficient for preserving suitable habitats and maintaining connected ape populations. Thus, conservation planners urgently need to integrate land use planning and climate change mitigation measures at all decision-making levels both in range countries and abroad

High aboveground carbon stock of African tropical montane forests

Tropical forests store 40-50 per cent of terrestrial vegetation carbon(1). However, spatial variations in aboveground live tree biomass carbon (AGC) stocks remain poorly understood, in particular in tropical montane forests(2). Owing to climatic and soil changes with increasing elevation(3), AGC stocks are lower in tropical montane forests compared with lowland forests(2). Here we assemble and analyse a dataset of structurally intact old-growth forests (AfriMont) spanning 44 montane sites in 12 African countries. We find that montane sites in the AfriMont plot network have a mean AGC stock of 149.4 megagrams of carbon per hectare (95% confidence interval 137.1-164.2), which is comparable to lowland forests in the African Tropical Rainforest Observation Network(4) and about 70 per cent and 32 per cent higher than averages from plot networks in montane(2,5,6) and lowland(7) forests in the Neotropics, respectively. Notably, our results are two-thirds higher than the Intergovernmental Panel on Climate Change default values for these forests in Africa(8). We find that the low stem density and high abundance of large trees of African lowland forests(4) is mirrored in the montane forests sampled. This carbon store is endangered: we estimate that 0.8 million hectares of old-growth African montane forest have been lost since 2000. We provide country-specific montane forest AGC stock estimates modelled from our plot network to help to guide forest conservation and reforestation interventions. Our findings highlight the need for conserving these biodiverse(9,10) and carbon-rich ecosystems. The aboveground carbon stock of a montane African forest network is comparable to that of a lowland African forest network and two-thirds higher than default values for these montane forests.Peer reviewe

Quantitative estimates of glacial refugia for chimpanzees (Pan troglodytes) since the Last Interglacial (120,000 BP).

Paleoclimate reconstructions have enhanced our understanding of how past climates have shaped present-day biodiversity. We hypothesize that the geographic extent of Pleistocene forest refugia and suitable habitat fluctuated significantly in time during the late Quaternary for chimpanzees (Pan troglodytes). Using bioclimatic variables representing monthly temperature and precipitation estimates, past human population density data, and an extensive database of georeferenced presence points, we built a model of changing habitat suitability for chimpanzees at fine spatio-temporal scales dating back to the Last Interglacial (120,000 BP). Our models cover a spatial resolution of 0.0467° (approximately 5.19 km2 grid cells) and a temporal resolution of between 1000 and 4000 years. Using our model, we mapped habitat stability over time using three approaches, comparing our modeled stability estimates to existing knowledge of Afrotropical refugia, as well as contemporary patterns of major keystone tropical food resources used by chimpanzees, figs (Moraceae), and palms (Arecacae). Results show habitat stability congruent with known glacial refugia across Africa, suggesting their extents may have been underestimated for chimpanzees, with potentially up to approximately 60,000 km2 of previously unrecognized glacial refugia. The refugia we highlight coincide with higher species richness for figs and palms. Our results provide spatio-temporally explicit insights into the role of refugia across the chimpanzee range, forming the empirical foundation for developing and testing hypotheses about behavioral, ecological, and genetic diversity with additional data. This methodology can be applied to other species and geographic areas when sufficient data are available

Densité et écologie des chimpanzés (Pan troglodytes schweinfurthii) dans le Parc National de la Kibira, Burundi

Les forêts tropicales africaines et les communautés de primates qu'elles abritent sont sérieusement menacées par l'accélération des taux de conversion et de dégradation des forêts ainsi que par les activités de braconnage. L'impact de ces menaces est si grand que certaines communautés de primates ont complètement disparu avant d’avoir été reconnues, encore moins étudiées. Des données référentielles sont toujours nécessaires pour comprendre les variations spatio-temporelles des primates. Les estimations de la densité ou d'abondance des populations sont des outils de première importance lors de la détermination des priorités de conservation et de la mise en place d’un plan de gestion des populations de primate. Comme dans les écosystèmes forestiers, la répartition et l’abondance des différentes espèces d’arbres influencent profondément les communautés animales qui y vivent, nous avons d’abord cherché à déterminer la densité et la structure des espèces d’arbres de la forêt de Kibira. Dans 256 plots couvrant une superficie de 32,15 ha, un total de 6.504 arbres répartis en 70 espèces, 67 genres et 37 familles ont été enregistrés. La densité était de 202 tiges par hectare, avec une surface basale de 21,05 m² par hectare. Au total, six espèces de primates diurnes ont été enregistrées dont une espèce anthropoïde (Pan troglodytes schweinfurthii), quatre cercopithecinae (Cercopithecus mitis, Cercopithecus mona denti, Cercopithecus lhoesti et Lophocebus albigena) et une colobinae (Colobus angolensis). Seule la densité et l’effectif total de la population des chimpanzés sont connus, tandis que pour le reste des espèces, seul l’indice d’abondance kilométrique a été calculé. Cette recherche a accordé une attention particulière à l’espèce emblématique du Parc National de la Kibira, le chimpanzé d’Afrique de l’est, Pan troglodytes schweinfurthii. Afin de mieux protéger cette sous-espèce en danger d’extinction, nous avons mené des investigations sur les sites de nidification pour identifier les espèces et les caractéristiques des arbres sur lesquelles les chimpanzés comptent pour la construction des nids. Les résultats ont montré que les chimpanzés sélectionnent certaines espèces d’arbres lors de la construction des nids. Le secteur Mabayi, situé au nord du parc, est le plus riche en espèces de primates; il abrite cinq espèces sur les six enregistrées, et deux espèces: Cercopithecus lhoesti (menacée) et Colobus angolensis ne se retrouvent qu’à Mabayi uniquement. Cette partie du parc constitue une clé pour la diversité et devrait par conséquent bénéficier d’une attention particulière en matière de protection et conservation

Chimpanzee (Pan troglodytes schweinfurthii)Population Density and Abundance in Kibira National Park,Burundi

Successful conservation and management strategy of wild animals usually starts by assessing their population size. This is of particular relevance in areas submitted to long periods of human conflicts which is the case of Burundi. A census of chimpanzee populations was made throughout Kibira National Park between September 2011 and February 2013 to provide reliable information on density estimates of chimpanzees inhabiting the forest. The method was based on marked nest counts from line transects which allowed the calculation of population densities of all weaned individuals. We recorded a total of 471 chimpanzee nests in four sectors of the park (Mabayi 290 nests, Rwegura 68 Teza 65 and Musigati 48). We derived an estimate of the total population of 203 (122-339) weaned chimpanzees in the whole park. We discuss that result in perspective of necessiry of future research on chimpanzees in Burundi. First, implementation of a monitoring program of chimpanzee is necessary to constitute a database, as well as collecting data of tree phenology on which chimpanzee depend. Second, an effective transboundary strategic plan to conserve Kibira-Nyungwe as one landscape is necessary to maintain viable population of chimpanzees.Densité et écologie des chimpanzés du Park National de la Kibir