People’s perceptions of crocodiles in Nigeria

Throughout Africa, feelings towards crocodiles vary according to the danger or fear experienced by communities living alongside them. Crocodile conservation programs must therefore be based on reliable assessments of cultural attitudes towards these reptiles. In this study, we interviewed a random sample of 300 persons in six states in southern Nigeria to determine their perception of crocodiles. Our results revealed that most respondents were very familiar with crocodiles, animals being regularly sighted but only in small numbers. Most interviewees were aware of just two crocodile types, consistently describing the dwarf crocodile (Osteolaemus tetraspis) and the West African Nile crocodile (Crocodylus [niloticus] suchus); only a minority of respondents reporting they were aware of the West African slender-snouted crocodile (Mecistops cataphractus)

State of knowledge of research in the Guinean forests of West Africa region

© 2017 Elsevier Masson SAS. The Guinean forests of West Africa (GFWA) region is of highest conservation value in Africa and worldwide. The aims of this review are to systematically identify and collate studies focusing on the environment in the region. We found that, after Google Scholar search, in over 112,000 results for 17 disciplines, three countries (Nigeria, Cameroon and Togo) were subjected to much more investigations than the other countries. Guinea, Liberia, and Sierra Leone were the least studied countries, and overall there was a significant West to East increasing trend for all seven considered disciplines (Ecology, Zoology, Botany, Conservation biology, Pollution, Climate change and Ecological economy) in terms of number of results. Within 'Ecology' 'macroecology and biodiversity' was the most studied subdiscipline. Baseline taxonomic studies in 'Zoology' and 'Botany' received little interest, particularly in 2006-2016. For 'Conservation biology', studies focusing on 'protected areas' were more numerous than for any other subsector, followed by 'biodiversity surveys'. Our analysis revealed that there were significantly more studies focusing on forests than on mangrove areas. Our results pointed out that, there is an urgent need for more rigorous taxonomical and fine-scale distribution studies of organisms across the whole region, not only for the traditionally overlooked groups (e.g. invertebrates). It is also stressed that studies of macropatterns in conservation biology research for the region should be performed by more reliable data at the more local scale, given the misuse that has been done by general studies of these limited/biased data for inferring patterns. Long-term longitudinal studies on biodiversity patterns of important forest sites and population biology of selected populations are urgently needed, as these have been almost entirely neglected to date. Crucial issues are still to be solved: for instance, it remains fully unresolved whether wildlife can best be protected through the promotion of human economic development or through integral conservation of important biodiversity areas

Predicting the structure of turtle assemblages along a megatransect in West Africa

Understanding large- and small-scale patterns as well as the determinants of species richness is central for the study of evolutionary mechanisms. The extent to which species richness in local communities is related to larger scale processes is a pre-eminent topic in ecological and evolutionary research. To investigate how local and regional species richness are related, we sampled freshwater turtle assemblages in seven localities to represent the variation in ecological conditions along a 90km South-North megatransect in Benin, West Africa. In each locality, all turtles captured were identified and measured, and microhabitat classified in which individual turtles were observed. Based on these data we used community diversity metrics to compare turtle assemblages. Spatial autocorrelation did not affect our data. For all localities pooled, only two species (Pelusios castaneus and Pelomedusa olivacea) were the most common, and one species (Trionyx triunguis) the rarest. Analyses of the commonest and more numerous species showed that the abundance of P. castaneus declined with an increase in latitude and longitude, but the opposite was true for P. olivacea. We showed that various microhabitat characteristics were significantly correlated with the abundance of the two common species. We found significant but variable South-North gradients in microhabitat use for different turtle species. Our results highlight the importance of studying interactions between local environments, the ecological requirements of each species, and their synecological relationships

Age-stratified interview campaigns suggest ongoing decline of a threatened tortoise species in the West African Sahel

Face-to-face interviews with local populations are often used to determine the distribution and population trends of elusive threatened species. Although interviewee responses may suffer from some bias, historical trends in the status of a species can be investigated from age-structured questionnaires. In this paper, we tested this idea by analysing separately answers given by older (> 60 years age) and younger respondents (25-44 years old) on the status of the African spurred tortoise, (Centrochelys sulcata), a charismatic large reptile listed as Vulnerable in the IUCN Red List. We interviewed 619 persons (hunters/farmers/cattle farmers) of different ages in three of the species’ habitat countries (Burkina Faso, Niger and Nigeria). Interviewees were asked whether in their experience the tortoise was common, rare or absent. By using Generalized Linear Models we showed that the probability to answer “common” increased with age in Nigeria and Burkina Faso, whereas the probability of responding “absent” declined with age in Nigeria and Niger. There were no significant effects of age for the answer 'rare' in any country and no differences were found between villages in any of the studied countries. From our data we conclude that spurred tortoises have been extirpated in 16.7% of study sites. We argue that if statistical differences emerge between answers given by respondents of various age classes on the population status of a target species, it is possible to conclude that the species’ situation may have significantly changed during the last 30-40 years

Community Characteristics of Sympatric Freshwater Turtles from Savannah Waterbodies in Ghana

Despite increasing pressures on freshwater resources worldwide, and the threatened status of most freshwater turtles, there is still limited knowledge of habitat use and niche partitioning in Afrotropical freshwater turtle communities. In this study, we describe habitat associations, community diversity, and temporal patterns of occurrence of freshwater turtle species in the Dahomey Gap ecoregion of Ghana (West Africa). We gathered data from 13 sites in central Ghana and along the Sene Arm of Lake Volta in the Digya National Park (Bono East Region). We employed opportunistic short-term surveys (at seven sites) together with longer-term (six-months duration) standardized evaluations of turtle presence and numbers in different habitats (at six sites). Overall, a total of 210 turtle individuals of four species (Trionyx triunguis, Cyclanorbis senegalensis, Pelomedusa sp. and Pelusios castaneus) were recorded; precise capture sites and habitat type were recorded for 139 individuals, but the 71 individuals observed in marketplaces were not considered in our analyses. At a local scale, we observed three sympatric species in various study sites. In each of these sites, the dominant species was either C. senegalensis or Pelomedusa sp., with the latter species being more abundant in temporary waterbodies and C. senegalensis more numerous in permanent ones. A Multiple Correspondence Analysis suggested that, in permanent waterbodies all species were associated with similar physical habitat variables. In a Canonical Correspondence Analysis, we showed that the density of herbaceous emergent vegetation was more important for P. castaneus than for C. senegalensis. Comparisons of diversity metrics between our study sites and previous studies revealed that turtle community composition was similar across savannah sites

Understanding the influence of non-wealth factors in determining bushmeat consumption: results from four West African countries

The meat of wild animals (bushmeat) is consumed extensively in many tropical regions. Over the past few decades bushmeat consumption has greatly increased, threatening the survival of some hunted species and the supply of animal protein to countless numbers of people. Understanding patterns of bushmeat consumption is thus vital to ensure the sustainable use of this resource. Although the economic drivers of bushmeat consumption has been well studied, non-wealth correlates have been poorly considered. Here, we analyse how factors such as age and gender influence bushmeat consumption in four West African countries, within the Guinean forests (Togo and Nigeria) and Sahel (Burkina Faso and Niger). We interviewed a total of 2,453 persons (1,253 urban, 1,200 in rural areas) to determine frequency of consumption of bushmeat as well as main species eaten. We found significant differences in bushmeat consumption between rural and urban areas in all four countries. In particular, the proportion of persons not consuming any bushmeat was highest in urban areas. Gender differences in bushmeat consumption was not generally important but young people consistently avoided eating bushmeat, especially in Togo and Nigeria, and in urban areas. The complicated interplay between tradition and evolution of social systems (especially the trends towards westernization) may explain the different perceptions that people may have towards consuming bushmeat in the four studied countries. In addition, we found considerable variation in types of bushmeat eaten, with antelopes and large rodents eaten by the great majority of interviewees, but bats, monkeys, and snakes being avoided, especially in urban settlements

The environmental impacts of palm oil in context

Delivering the Sustainable Development Goals (SDGs) requires balancing demands on land between agriculture (SDG 2) and biodiversity (SDG 15). The production of vegetable oils, and in particular palm oil, illustrates these competing demands and trade-offs. Palm oil accounts for 40% of the current global annual demand for vegetable oil as food, animal feed, and fuel (210 million tons (Mt)), but planted oil palm covers less than 5-5.5% of total global oil crop area (ca. 425 Mha), due to oil palm’s relatively high yields5. Recent oil palm expansion in forested regions of Borneo, Sumatra, and the Malay Peninsula, where >90% of global palm oil is produced, has led to substantial concern around oil palm’s role in deforestation. Oil palm expansion’s direct contribution to regional tropical deforestation varies widely, ranging from 3% in West Africa to 47% in Malaysia. Oil palm is also implicated in peatland draining and burning in Southeast Asia. Documented negative environmental impacts from such expansion include biodiversity declines, greenhouse gas emissions, and air pollution. However, oil palm generally produces more oil per area than other oil crops, is often economically viable in sites unsuitable for most other crops, and generates considerable wealth for at least some actors. Global demand for vegetable oils is projected to increase by 46% by 20509. Meeting this demand through additional expansion of oil palm versus other vegetable oil crops will lead to substantial differential effects on biodiversity, food security, climate change, land degradation, and livelihoods. Our review highlights that, although substantial gaps remain in our understanding of the relationship between the environmental, socio-cultural and economic impacts of oil palm, and the scope, stringency and effectiveness of initiatives to address these, there has been little research into the impacts and trade-offs of other vegetable oil crops. 65 Greater research attention needs to be given to investigating the impacts of palm oil production 66 compared to alternatives for the trade-offs to be assessed at a global scale

Tortoise ecology in the West African savannah: multi-scale habitat selection and activity patterns of a threatened giant species, and its ecological relationships with a smaller-sized species

The status of most vertebrates in the African Sahel is not well known. Among these, the African spurred tortoise (Centrochelys sulcata), a charismatic but also one of most threatened vertebrates in the Sahel, is still poorly studied. We investigated the status of this species, its potential distribution, habitat selection (at multiple spatial scales) and activity patterns in Mali and Burkina Faso, two countries within the tortoise’ known range. We employed field surveys and villager interviews in 23 sites to determine the presence of the species. In these surveys and interviews, we also included the Western hinge-back tortoise (Kinixys nogueyi), a sympatric chelonian also suspected of being in decline. Age-stratified interviews revealed that C. sulcata is widespread in Mali, but since there was a statistically higher frequency of older respondents that remembered C. sulcata present around their village, compared to younger respondents, it is likely that the species has been declining throughout the study area. We encountered a total 77 C. sulcata and 20 K. nogueyi individuals during our field surveys. Most C. sulcata were found along areas of intermittent streams and stabilised dunes, known locally as koris. Centrochelys sulcata individuals were more likely to occur in sandy dry savannah areas that were further away from human settlements, and which contained inland waters or were closer to these. Kinixys nogueyi exhibited instead an allopatric distribution, with no ascertained sympatry with C. sulcata at the microhabitat scale. Cattle incidence was negatively correlated with the presence by C. sulcata. Our results also indicate that aboveground activity of C. sulcata is limited to the wet season and has a clearly bimodal diel activity cycle, with most sightings in the early morning hours. We provide suggestions on how best to survey this species in the wild while advancing new information on its distribution and biology. These data are invaluable to assess the status of this species as part of future conservation planning efforts

Generalist, selective or ‘mixed’ foragers? Feeding strategies of two tropical toads across suburban habitats

Suitable habitats for anurans can be found in the ever-growing tropical urban environments but anurans' adaptations to urban conditions, including their trophic ecology remain largely unknown. We studied the food habits of two generalist, widespread West African Sclerophrys adult toads: African common (Sclerophrys regularis) and Hallowell's toad (Sclerophrys maculata). The first was studied in Lomé (Togo), Cotonou (Benin) and Ikeja (Nigeria), and the second in Port Harcourt and Ikeja (both Nigeria); the latter city represents the only studied sympatric occurrence. Mean dietary overlap between population pairs was relatively high, and diet composition of the two species when sympatric did not differ significantly. Food niche width was significantly positively correlated with local rainfall in both species, and diet composition changed significantly between the dry and wet seasons. Diversity metrics revealed that females had a more diversified diet, with higher evenness and lower dominance index values than males. The diet of both species was not correlated to prey type availability, in both the wet and dry season. Both toad species targeted specific food items rather than opportunistically consume prey as observed in most anurans which may be a response to high anuran diversity typically found in the tropics or an adjustment to urban habitats