7 research outputs found
Do primate action plans work?
John Oates authored the first primate conservation Action Plan in 1986, which assessed the status of and proposed conservation actions for all mainland African primate species. A revised version of the continent-wide plan was published in 1996, but since then, action plans have generally evolved into prioritizing actions for specific species, often within defined landscapes. We will review and evaluate the content and success of conservation action plans for the nine currently recognized taxa of chimpanzees and gorillas in Africa. Since 2003, six detailed action plans and one population viability analysis have been published, covering priority actions and landscapes for seven of the nine great ape taxa in Africa. Two further action plans (for gorillas and chimpanzees in Eastern DRC and for bonobos) are in the final stages of review and may also be included in the analysis. Assessments for western chimpanzees, Cross River gorillas, western lowland gorillas and central chimpanzees have been peer reviewed, and we will consider their recommendations and the challenges of quantitatively evaluating the success of primate conservation action plans
Regional Action Plan for the Conservation of the Cross River Gorilla (Gorilla gorilla diehli)
From Executive Summary: This document represents the consensus of experts who met at a workshop in April 2006 in Calabar, Cross River State, Nigeria, to formulate a set of priority actions that would increase the survival prospects for the Cross River gorilla (Gorilla gorilla diehli). The Cross River gorilla is recognized by IUCN as Critically Endangered, and is the most threatened taxon of ape in Africa. It is the most westerly and northerly form of gorilla, and occurs only in a limited area around the mountainous headwaters of the Cross River, straddling the border between Cameroon and Nigeria. Participants at the 2006 workshop, which built upon the outcomes of previous meetings in Calabar in 2001 and Limbe, Cameroon, in 2003, included representatives of forestry and wildlife conservation agencies from the two range countries, of local and international nongovernmental conservation and development organizations, and of university-based researchers
Regional Action Plan for the Conservation of the Nigeria–Cameroon Chimpanzee (Pan troglodytes ellioti)
First paragraph: This document represents the consensus of views from forestry and wildlife conservation agencies in Nigeria and Cameroon, local and international nongovernmental conservation organizations, and university-based researchers who met at a series of workshops in Cameroon and Nigeria to formulate a set of actions that, if implemented, will increase the longterm survival prospects of the Nigeria-Cameroon chimpanzee, Pan troglodytes ellioti. The Nigeria-Cameroon chimpanzee is the most endangered of all currently recognized chimpanzee subspecies, with a total remaining population of between 3,500 and 9,000 living in forested habitat to the north of the Sanaga River in Cameroon, the eastern edge of Nigeria, and in forest fragments in the Niger Delta and southwestern Nigeri
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
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
Past Connectivity but Recent Inbreeding in Cross River Gorillas Determined Using Whole Genomes from Single Hairs
The critically endangered western gorillas (Gorilla gorilla) are divided into two subspecies: the western lowland (G. g. gorilla) and the Cross River (G. g. diehli) gorilla. Given the difficulty in sampling wild great ape populations and the small estimated size of the Cross River gorilla population, only one whole genome of a Cross River gorilla has been sequenced to date, hindering the study of this subspecies at the population level. In this study, we expand the number of whole genomes available for wild western gorillas, generating 41 new genomes (25 belonging to Cross River gorillas) using single shed hairs collected from gorilla nests. By combining these genomes with publicly available wild gorilla genomes, we confirm that Cross River gorillas form three population clusters. We also found little variation in genome-wide heterozygosity among them. Our analyses reveal long runs of homozygosity (>10 Mb), indicating recent inbreeding in Cross River gorillas. This is similar to that seen in mountain gorillas but with a much more recent bottleneck. We also detect past gene flow between two Cross River sites, Afi Mountain Wildlife Sanctuary and the Mbe Mountains. Furthermore, we observe past allele sharing between Cross River gorillas and the northern western lowland gorilla sites, as well as with the eastern gorilla species. This is the first study using single shed hairs from a wild species for whole genome sequencing to date. Taken together, our results highlight the importance of implementing conservation measures to increase connectivity among Cross River gorilla sites