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Biological communities are structured by a variety of biotic and abiotic relationships, whose understanding forms the basis for effective conservation. Among the myriad factors influencing community dynamics, resource partitioning stands out, potentially enriching ecosystem complexity but also carrying risks for conservation if disregarded. In this study, we investigated intersexual and ontogenetic niche differences among populations of the West African softshell turtle Trionyx triunguis in Liberia, Cote d'Ivoire, Ghana and Nigeria. We observed that these distinct populations exhibited similar habitat preferences, favouring large rivers with abundant riverbank and aquatic vegetation, and muddy substrates. Disparities in habitat preferences were evident among populations and across various life stages, indicating the adaptability of the species. We found that the species was active throughout the year, but most of our sightings and captures occurred during the wet season. In light of the species' vulnerability to overhunting, our research findings provide important data on the ecology of this species that can assist in its effective conservation across all life stages. [ABSTRACT FROM AUTHOR]

The village weaver (Ploceus cucullatus) is a common colonial nesting bird widespread throughout Sub-Saharan Africa. It is known to weave its nests from leaf strips from a variety of tree species (mainly coconuts trees, oil palm trees) associated with human settlement areas, grasses, and other available plants. In this regard, this bird was considered a pest for its impact on different economic activities. Although extensive literature is already available on the parasitic role of village weavers, there is still a lack of analytical data that outlines which tree species are used for nesting and in what proportion, as well as the related implications in terms of economic impacts. Here, we carried out the first comprehensive arrangement of trees used by this species for nesting in Southern Nigeria (West Africa), checking for possible different impacts on stakeholders. In April 2021, we searched for village weaver nesting in 95 sites in 77 communities from 24 local government areas in Southern Nigeria, during 14 field surveys. Within each site, we collected GPS coordinates and counted the number of active nests, nesting birds and occupied trees. We recorded a total of 5,776 nests and 2,140 birds in 94 plants belonging to 23 tree species selected for nesting. Oil palm (Elaeis guineensis; n = 45) was the most used tree species, as 2,990 (51.77%) nests and 873 (40.79%) birds were recorded. Our results indicate the preference for nesting on trees used by stakeholders belonging to agricultural (palm farmers), touristic (operators) and energy (gas flare stations) sectors with economic implications about the conflict with this pest species. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 on the International Union for Conservation of Nature Red List. We interviewed 619 people (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. Using generalized linear models, we showed the probability of answering 'common' increased with age in Nigeria and Burkina Faso, whereas the probability of responding 'absent' declined with age in Nigeria and Niger. We argue that if statistical differences emerge between answers given by respondents of various age classes on the population status of a target species, the species' situation may have changed significantly during the last 30–40 years. [ABSTRACT FROM AUTHOR]

There is an unprecedented demand for bushmeat in large cities in sub-Saharan Africa, and this is a major threat to many species. We conducted 2,040 interviews in six cities in four West African countries, in forest and savannah settings. We analysed age- and sex-related differences in the frequency of bushmeat consumption. Overall, we found similar patterns in all cities: 62.2% of men and 72.1% of women said they would never eat bushmeat, whereas 12.8% of men and 8.8% of women said they liked bushmeat and ate it regularly. Younger generations of both sexes tended not to eat bushmeat, regardless of their city of origin. This study of the effects of age, gender and geographical location on bushmeat consumption in African cities provides insights regarding which population groups to target in campaigns to change behaviours. [ABSTRACT FROM AUTHOR]

Understanding large- and small-scale patterns and 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 90 km south–north megatransect in Benin, West Africa. In each locality, all turtles captured were identified and measured, and the microhabitat in which individual turtles were observed was classified. Based on these data, we used community diversity metrics to compare turtle assemblages. Spatial autocorrelation did not affect our data. For all localities pooled, two species (Pelusios castaneus and Pelomedusa olivacea) were the most common and one species (Trionyx triunguis) was the rarest. Analyses of the commonest and more numerous species showed that the abundance of Pelusios castaneus declined with an increase in latitude and longitude, but the opposite was true for Pelomedusa olivacea. We showed that various characteristics of the microhabitat 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. [ABSTRACT FROM AUTHOR]

Actuarial senescence appears to be a common process, and senescence patterns are highly variable across the tree of life. To date, studies on animal senescence have largely focused on model species, such as as fruit flies, humans and a few other endotherms. In contrast, our knowledge about ageing remains fragmentary in ectotherm vertebrates, such as reptiles. Here, we examined life history and age-dependent mortality patterns in three tropical tortoises (Kinixys erosa , Kinixys homeana and Kinixys nogueyi) and snakes (Bitis gabonica , Bitis nasicornis and Causus maculatus). Our study revealed that tortoises of the genus Kinixys had a higher survival and a lower recruitment than snakes of the genera Bitis and Causus , indicating a slower life history. Furthermore, we confirmed that survival decreased more slowly with age in tortoises than in snakes. In addition, we highlighted contrasting patterns of age-dependent mortality among the three genera. In Kinixys , the relationship between mortality rate and age was positive and linear, suggesting gradual senescence over tortoise lifetime. In contrast, the relationship between mortality rate and age was negative and sharp in Bitis and Causus , possibly owing to a 'negative senescence'. Our study is one of the few to have examined and compared the demography and age-dependent mortality patterns of tropical reptiles. Among other things, our results suggest that although negative senescence has never been reported in endotherm vertebrates, it could be a common phenomenon in ectotherms. [ABSTRACT FROM AUTHOR]

To better understand the habitat preferences of the African spurred tortoise (Centrochelys sulcata), we tested possible associations between their distribution and land use, vegetation cover, the presence of roads, human settlements, and rainfall patterns, all of which affect the distributions of other tortoise species. African spurred tortoise distribution (based on 36 presence points compared with 250 random points) was strongly associated with 3 variables we analyzed: 1) Corine Land Cover (CLC) categories (especially sites with deciduous shrubs and high herbaceous cover relative to random bare areas), 2) distance from human settlements, and 3) distance from the nearest road. [ABSTRACT FROM AUTHOR]

The article discusses the agricultural technique shifting cultivation practiced in tropical regions which have become the primary cause of deforestation and threat to the wildlife. It also discusses the slash‐and‐burn agriculture in the humid forests of West Africa and deforestation caused by it, including the comparison of diversity metrics and community composition of reptiles for slash‐and‐burn agriculture sites and unburnt sites in the Niger Delta region of southern Nigeria.

The forest hingeback tortoises Kinixys homeana and Kinixys erosa are two of the most declining African chelonians. Although the population size trends of these species have received attention in some specific areas of West Africa, an overall perception of their declining trajectories are still largely unexplored. We used interviews with rural people (hunters, farmers and snail gatherers) in order to explore the general perception that these experienced people have on the population trends of these threatened tortoises. Overall, we interviewed over 2000 people in three West African countries (Côte d'Ivoire, Togo and Nigeria), which mostly supported the notion that these tortoises are heavily declining in Togo and Nigeria, but less so in Côte d'Ivoire. In addition, many respondents suggested that snail gatherers are the main providers of tortoises to the bushmeat trade. Indeed, our market surveys revealed that, in Nigeria, there was a significantly positive correlation between number of wild snails traded by individual sellers and numbers of sold tortoises in their 'shops'. [ABSTRACT FROM AUTHOR]

The African spurred tortoise Centrochelys sulcata is the second largest terrestrial turtle, with a scattered distribution across the West African Sahel. This species is threatened and declining consistently throughout its range, but little is known about the causes of its decline. It has been hypothesized that the decline is attributable to (1) competition with domestic cattle, (2) wildfire, and (3) the international pet trade. We conducted a series of analyses to investigate these three causes. Hypotheses 1 and 2 were analysed using a spatially explicit approach, using a database of the Food and Agriculture Organization of the United Nations and logistic regression modelling; hypothesis 3 was tested by analysing the CITES trade database for 1990–2010. We found a significant negative correlation between intensity of grazing (expressed as density of cattle, km−2) and the presence of spurred tortoises, and this negative effect increased when coupled with high fire intensity, whereas wildfires alone did not have a significant influence on the species’ distribution at the global scale. There was a decrease in the annual export of wild individuals for the pet trade after the introduction of export quotas by country and by year, but trade data must be considered with caution. [ABSTRACT FROM AUTHOR]

Lygodactylus conraui is the only green gecko species occurring in West Africa, and is also one of the smallest gecko species of the African continent. Here, some aspects of the natural history of this species are documented for Rivers State, southern Nigeria. In total, 108 L. conraui individuals were observed in 1996-2016 in southern Nigeria. Individuals of this species were mainly observed at originally forested sites that were heavily altered by human inclusion. In southern Nigeria, L. conraui may be a pioneer species that quickly colonises microhabitats at ecotonal sites of recently deforested or rapidly re-growing forest areas. In each site, the number of observed lizards was significantly positively influenced by the percent of available shade within each habitat type. These geckos were found most commonly at 0.8-3.2 m height. Their activity was especially concentrated during the wet season months. Mean distance between individuals in each demes was 1.35 m (range 0.70-3.2 m). [ABSTRACT FROM AUTHOR]

The leopard (Panthera pardus) is increasingly threatened in West Africa, and is apparently very rare and has been driven to extinction across much of Nigeria. In the Niger Delta, where it is considered extremely threatened, with very few sightings in the last decades. In this study we document both direct (skins, footprints, scats, etc.) and indirect (village hunter’s interviews) signs of leopard presence in order to reconstruct leopard presence in the Niger Delta, across the period 2000–2015. Data were combined into three survey periods: 2000–2002, 2006–2008 and 2012–2015, and compared with literature data for 1996–1997. Recent skins were recorded in 2.2–4.3% of the villages (n = 39–62). In addition, the leopard was reported to be present by hunters in another 3.3–10.3% of the villages. Overall, some specific sectors of the Delta were recurrently target of both direct and indirect signs of leopard presence (barrier islands and flood forest along the central axis of the River Niger), but all direct sightings occurred in a few barrier islands. In the Niger Delta, there was no evidence of females with cubs since decades and a few skins were the only direct signs of leopard’s current presence. Our results suggest that leopard populations may be functionally extinct in the Niger Delta, with just a few vagrant individuals, in dispersal and/or hunting, being still found. Barrier island forests are apparently the last vegetation zone of the Delta still potentially inhabited by leopards, and deserve careful managements in the years to come. [ABSTRACT FROM PUBLISHER]

The bushmeat trade in West and Central Africa embraces a broad range of ecological, economic, and conservation issues. To date, most studies have focused on the economic and conservation aspects of the bushmeat trade, with less emphasis on the ecological implications of wildlife extraction. Here, we analysed available literature on the bushmeat trade in 5 countries in west and central Africa exploring ecological traits such as niche width breadth and trophic position of the species involved, and habitats impacted. We also examine temporal changes over a 40-year period. Our results confirm that mammals dominated the trade in all studied areas and time periods, in terms of (i) number of species, (ii) number of traded individuals, and (iii) overall biomass. Herbivores were the most common trophic animal guild traded. Forest-specialists were the most abundant in the trade, and in riverine habitats reptile biomass almost as important as mammals. Overall, the most traded species and individuals were non-threatened according to the IUCN Red List. Our temporal analyses indicated that more habitat generalist and water-linked species were traded during 1971 - 2000, but forest dependent taxa predominated during the following decade (2001 - 2010). Additionally, the number of individuals of large-bodied herbivores rose relative to small and medium-sized ones, whereas traded biomass over time increased: (a) in the consumption of super-predators; (b) of large-bodied herbivores, but (c) a significant decrease in consumed biomass of medium and small-bodied herbivores. We suggest that the observed trends may suggest an imminent reduction of large-bodied herbivores and, as a cascade effect, also of super-predators in African moist forests. [ABSTRACT FROM AUTHOR]

The article discusses research concerning the habitat loss of tortoises (genus Kinixys) due to overhunting, climate change and human threat in Niger Delta. Information about the distribution and relative density of tortoises inside protected areas, is provided. An overview on the methods used as well as results and discussion about the research, is also given.

The ecology of West African arid savannah snakes is still poorly known, especially in regard to the fossorial species. Here, field data on distribution, morphometrics, habitat use and diet are reported for the sand boaEryx muelleri(Erycidae) from three different countries, i.e. Burkina Faso, Togo and Nigeria. This snake was observed in 21 distinct localities, and a total of 39 individuals was recorded. The species is likely fairly common and locally abundant. Mean body length of snakes was similar among countries and between sexes, but males had proportionately longer tails than females. Body length was significantly positively correlated with both tail length and head length. Adult sex ratio was close to parity. Most of the specimens were found in well-vegetated spots with low percentage of bare soil. There were apparently both ontogenetic and intersexual dietary variations: (1) a single analysed juvenile fed upon a small-sized lizard, whereas adults fed considerably upon young rodents; and (2) females fed exclusively upon young rodents and males upon both lizards and young rodents. In conservation terms, the species is actively exported from Togo for the pet trade, and additional individuals may also be illegally collected in other countries. [ABSTRACT FROM AUTHOR]

Community composition and an index of relative abundance were analyzed for mammals (excluding most rodents, shrews and bats) of five forest reserves in the Niger Delta (Southern Nigeria). Twenty-nine species were recorded, 86.2% of them being found in all protected areas. Although most of the species were already known from the study area, there were unexpected patterns concerning the duikers. Indeed, the presence of only one species (Philantomba walteri) (CH Smith, 1827) was confirmed, whereas at least five additional duiker species were reported for the study area by earlier authorities. Another duiker species (Cephalophus nigerGray, 1846) was recorded once during the present surveys and is not known whether it represents a stabilized presence in the Niger Delta. The empirical Abundance Index suggested that only three species were very rare (Trichechus senegalensis(Link, 1795),C. niger, andPan troglodytes(Blumenbach, 1775)). Diversity-dominance diagrams showed that the evenness profiles were similar across study areas. Linear distance (Km) between the barycenters of forest reserves was significantly positively correlated with relative community composition dissimilarity. Overall, a biotic homogenization process for the mammal communities of the five forest reserves was observed, likely as an outcome of the high deforestation of the last 50 years. [ABSTRACT FROM AUTHOR]

Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Monitoring of bushmeat markets has traditionally been seen as a source of faunistic and ecological data on mammal communities in West Africa. Nonetheless, it is largely unexplored whether datasets coming from monitoring of large "hub" markets in towns can reliably picture the mammal faunas and community compositions at the local level. Here, Swali market in Bayelsa State, Nigeria, that is one of the largest bushmeat markets in the Niger Delta, was monitored for six months in 2013-2014. Data from Swali market were compared with those collected during regular field surveys at five protected forests situated within 15 km radius from the market. A total of 21 mammal species was recorded at Swali versus 29 in the five protected forests. The trade was more intense by wet season. There was a statistically significant linear relationship between mean weight of the sold mammal and its price. A considerable portion of species that occur at the protected forests did not occur in the market samples, including the very rare species and the smallsized species. However, the abundance in the market of the common species was positively related to their apparent field abundance in the forest reserves. Therefore, it is concluded that large-sized bushmeat markets did not depict reliably the whole faunal composition and the community structure of mammals in West Africa, although these types of surveys are sufficient to characterize the abundance distribution of the common species at the regional scale. [ABSTRACT FROM AUTHOR]

In this study, the sex ratio, habitat use, and diet of free-rangingKinixys nogueyiare examined. Sex ratio and habitat use were examined in Togo and Nigeria (West Africa), and food habits only in Nigeria. Sex ratios were equal in both populations. Tortoises had clear habitat preferences in both countries, and the Nigerian population exhibited seasonal but not inter-sexual differences in habitat selection. The present study demonstrated that this species inhabits not only Guinea savannahs and relatively wet savannahs, as already reported in the literature, but also rainforest patches and hilly forests, especially in Togo. Food remains in the feces of Nigerian specimens belonged to plants and fungi as well as to animals, with inter-seasonal but not inter-sexual differences in dietary composition. In particular, there was a significant shift from a diet based mostly on animal food in the dry season towards a mainly vegetarian diet in the wet season. [ABSTRACT FROM PUBLISHER]

The inter-habitat and inter-seasonal variations in the taxonomic diet composition of the African fire skink, Lygosoma fernandi, one of the largest Scincidae of the Afrotropical regions, were studied by analysis of excrements collected from live individuals that were captured in some areas of the Niger Delta region, southern Nigeria. 22 prey types, mostly arthropods, were found in the diet of this species, with significant differences in prey composition between seasons. Isopoda and Coleoptera dominated in the dietary samples, with very few prey types exclusive of one habitat type and/or season (e.g. Formicidae in dry forest in both seasons and lizards in swamp forest in wet season). Overall, no difference between forest types and seasons was found as for diversity and evenness indices except for that prey diversity was higher in feces collected in the dry forest in dry season, whereas dominance and evenness did not show any significant variation across forest types. [ABSTRACT FROM AUTHOR]

Niche partititioning patterns have not been studied so far in burrowing tropical snakes of the families Typhlopidae and Leptotyphlopidae. In this study, we analyze temporal (= monthly activity) and spatial (= habitat use) niche dimensions in three species of burrowing snakes from the Niger Delta, Nigeria. Null model analyses, using two randomization algorithms and 30000 Monte Carlo permutations, showed that there was random resource partitioning patterns as for the spatial niche dimension. One species (Rhinotyphlops punctatus) clearly dominated in the sample, and appeared to be more habitat generalist than the others. All three species showed an uneven monthly activity, with peaks occurring by wet season, and statistically significant positive correlations between mean monthly rainfall and number of captured snakes. However, there were significantly negative correlations between mean monthly temperature and number of captured snakes in two of the three species (Rhinotyphlops congestus; Leptotyphlops cfr. sundewalli). [ABSTRACT FROM AUTHOR]

The Edumanon Forest Reserve is one of the least explored protected areas in the Niger Delta region of southern Nigeria, West Africa. In this article, we report the results of preliminary surveys, conducted between 2011 and 2014, for determining a checklist and a relative estimate of abundance for three groups of vertebrates, namely mammals, reptiles, and amphibians. Overall, we detected 69 vertebrate species (birds excluded), several of them being of high conservation concern. Among the most remarkable species from the conservation point of view, we can cite the chimpanzee, the manatee, and three species of sympatric crocodiles. Analysis of the reptile diversity suggested that species dominance was high and evenness was low, thus revealing altered ecological conditions in this forest area. Nonetheless, several forest specialists were still observed in this forest reserve. The conservation implications of the observed patterns, together with some ethnozoological data, are also discussed. [ABSTRACT FROM AUTHOR]

The diet composition of rainbow lizards (Agama agama complex) populations was studied by feces analysis at eight distant places across a mega-transect in the Gulf of Guinea (West Africa), covering three countries: Togo, Benin and Nigeria. The effects of geography (= linear distance between study sites) and local conditions (using the mean annual rainfall as a proxy of the site-specific conditions) on dietary similarity of rainbow lizards were tested. Rainbow lizards were mainly insectivorous at all sites. Multivariate analyses identified four main groups of localities in terms of diet diversity indexes, with populations inhabiting forest towns tending to have less prey taxa richness than conspecifics from more arid areas, which instead had higher dietary evenness. Food niche overlap between populations was high among populations (range 0.631-0.940, x = 0.839), and decreased with increases in the difference of mean annual rainfall between sites. There was no effect of the geographic distance on the similarity in diet composition between populations. A UPGMA dendrogram revealed a geographic trend in terms of presence/absence of the various prey types in the diets, with all the Nigerian study sites forming one cluster, whereas Lomé and Cotonou, two cities situated within the Dahomey Gap, being grouped apart. Overall, rainfall of the various sites seems to be more important than geographic distance for determining the taxonomic diet composition similarity of these lizards. [ABSTRACT FROM AUTHOR]

The article presents ecological data for the snake Crotaphopeltis hotamboeia found in southern Nigeria. Highlights of the study include the significantly larger body size attained by females when compared to males, the peaking of above-ground activity during the wet months and the preponderance of snakes that were captured in agricultural lands such as plantations and farmlands. It also compared the diet composition of both sexes.

The food habits of a freshwater pelomedusid turtle (Pelomedusa subrufa) were studied by fecal analysis and stomach flushing in 2 study areas in Nigeria. Males and females were predominantly carnivorous; they fed mainly on fish, tadpoles, and aquatic invertebrates but also on terrestrial vertebrates. Sexes overlapped highly in dietary habits during both wet and dry season. Body size clearly affected diet composition of turtles but did so only during the dry season (with smaller individuals feeding primarily on invertebrates and small vertebrates, and larger individuals on homeotherm vertebrates). There was a strong effect of season on diet composition, and turtles responded to increasing dryness with a shift from a diet based on aquatic organisms during the wet season to a diet based on terrestrial organisms, including small vertebrates, during the dry season. [ABSTRACT FROM AUTHOR]

Stomach flushing is one of the proposed techniques to study lizard diets. Apparently, it is ranged, together with direct observation and faecal analysis, as a non-harmful method for dietary studies. Some works explored the usefullness of stomach flushing, but we lack information about its effect on lizard's survival probabilities. In this paper we studied the effect of stomach flushing in an urban population of the rainbow lizard (Agama agama) from Calabar (Nigeria). During a period of five months of 2010, 147 lizards were noosed, sexed and individually marked. One group of lizards was stomach flushed only once, whereas the rest of lizards were not flushed. The flushed sample of lizards showed a lower survival than non-flushed lizards of all sex and age classes. In this study, the pictured diet from stomach flushing was very similar to results obtained with a faecal analysis of the same lizard population. Thus, both methods seem to be reliable to study the diet of the rainbow lizard. However, our results indicate that stomach flushing increases the probability of mortality (or at least emigration rates) in all age and sex classes, precluding its extensive use as a method to study lizard's diets. [ABSTRACT FROM AUTHOR]

The article focuses on the possible effects of climate change on the high- and low-abundance populations of the nose-horned viper Bitis (B) nasicornis and the Gaboon viper Bitis gabonica in Nigeria. The five climatic variables that affect the populations of B. gabonica were precipitation of driest month, precipation of driest quarter, annual mean temperature, mean temperature or driest quarter and mean temperature of warmest quarter. Delta, Rivers and Akwa-Ibom States were the most ideal areas in southern Nigeria for high-abundance populations of Gaboon vipers in terms of climate. The future ideal areas for the high-abundance populations of nose-horned viper are western Nigeria, south-east of Nigeria and the nearby Cameroon.

Copyright of African Journal of Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article presents a study which investigated the daily and seasonal activity patterns and habitat selection of the African fire skink at a coastal site in southeastern Nigeria. It is stated that the wet season brought more above-ground activities regardless of their availability in the field and showed a preference for swamp forest and lowland forest patches. The authors concluded that high ambient temperatures around midday affected bi-modal diel activity patterns forcing the skinks to rest inactive inside their burrows.

The article discusses the impact of Ebola virus spreading on the consumption of bushmeat in southern Nigeria. The authors examine the correlates between Ebola, conservation biology and the social-economic issues related to bushmeat trade modifications. According to them, collapse in the bushmeat trade may affect the local people's economic activities.

Aspects of community structure and ecology of snakes were studied in the years 2004–2006 in fields of oil palm trees ( Elaeis guineensis) of three study areas in Southern Nigeria. A total of 284 individual snakes, belonging to twelve species of three families (seven Colubridae, four Elapidae, one Viperidae), were recorded, including both sighted and captured individuals (not including in this count the individuals that escaped before identification to species level could be made). All the study areas were nearly identical in terms of species composition. Most snakes (about 67%) were recorded during the dry season months, when the fruits of the oil palm ripe, thus attracting lots of organisms that are potential prey for snakes. The most important food items for oil palm snakes were Agama lizards, birds and rodents, but they also fed on skinks, geckos, fruit bats and tree frogs. Snakes were spotted climbing with peak frequencies occurring in the range of 16–18 m above the ground level. In general, oil palm trees within the range of 16–27 m high harboured higher number of snakes. Climbing snakes were nonrandomly positioned on the trees: the highest percentage of snakes (68%) was lodged between the leaf bases and oil palm fruit bunches. The general implications of the given data are discussed. Résumé Divers aspects de la structure communautaire et de l’écologie des serpents ont étéétudiés entre 2004 et 2006 dans des champs de palmiers à huile ( Elaeis guineensis) du sud du Nigeria. On a rapporté un total de 284 individus appartenant à 12 espèces de trois familles (7 Colubridae, 4 Elapidae, 1 Viperidae), y compris des individus aperçus et capturés (ne sont pas inclus dans ce calcul les individus qui se sont échappés avant que l’on puisse en identifier l’espèce). Toutes les zones de l’étude présentaient une composition des espèces presque identique. La plupart des serpents (près de 67%) ont été enregistrés au cours des mois de saison sèche, lorsque les fruits du palmier à huile mûrissent, ce qui attire de nombreux organismes qui sont des proies potentielles pour les serpents. Les proies principales des serpents des palmiers à huile étaient les agames, les oiseaux et les rongeurs, mais ils se nourrissaient aussi de scinques, de geckos, de roussettes et de grenouilles arboricoles. On a aperçu des serpents qui grimpaient, la hauteur la plus fréquentée étant entre 16 et 18 mètres au-dessus du sol. Ce sont en général les palmiers qui culminaient entre 16 et 27 mètres qui recelaient le plus grand nombre de serpents. Les serpents grimpeurs ne se répartissaient pas au hasard dans les arbres : le plus fort pourcentage (68%) d’entre eux se positionnaient entre la base des feuilles et le régime de fruits. Les implications générales des données sont discutées. [ABSTRACT FROM AUTHOR]

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The large-scale effects of habitat alteration produced by oil-industry related pollution on the habitat use of four species of freshwater turtles were studied in the River Niger Delta, southern Nigeria (West Africa). The numbers of turtle specimens observed during our study declined drastically in polluted sites, despite a nearly identical field effort. The number of specimens of all turtle species declined considerably at all habitat types, but complete disappearance in polluted areas was found only with regard to one habitat type for Trionyx triunguis and two habitat types for Pelomedusa subrufa. The mean values of species dominance and diversity indexes were not statistically significant between pristine and altered areas. A multivariate set of analyses (UPGMA) showed that the turtles were arranged in three 'ecological' clusters: a group formed by Pelomedusa subrufa at both polluted and unpolluted areas and Trionyx triunguis at polluted areas; (ii) a group formed by Pelusios castaneus in polluted areas and Pelusios niger in polluted areas; (iii) a group formed by Pelusios castaneus in unpolluted areas and Pelusios niger in unpolluted areas. Habitat use similarity among turtles in both polluted and unpolluted study areas was evaluated by the use of two types of overlap formulas and the use of Monte Carlo randomisations in order to control for the eventual role of chance in the actual data matrix. These data indicated that, for a pair of species (Pelusios niger vs. Pelusios castaneus), there was a statistically significant increase in the similarity of habitat use in the polluted areas vs. The unpolluted areas, and that this pattern was not dependent on the chance. Considering that these two species are ecologically and morphologically similar, we conclude that the most likely consequence at the community level is an increase in the intensity of interspecific competition for space between Pelusios niger and Pelusios castaneus in the polluted areas. [ABSTRACT FROM AUTHOR]

Focuses on a study which reported some data on the habitat use and season in sympatric populations of Grayia smythii and Afronatrix anoscopus from a swamp rainforest in southern Nigeria. Description of the study area; Three main habitat types for these semi-aquatic snakes were identified in the study area; Habitat use of specimens of Afronatrix anoscopus and Grayia smythii.

The relationships between population abundance, body size, food habits and ecological guild (aquatic, terrestrial, arboreal, and fossorial) of snake communities are studied in three different habitats (swamp-rainforest, mangrove forest and derived savanna) of southern Nigeria, West Africa. There were slightly positive relationships between body size and population abundance of snakes in the three study habitats of tropical Nigeria, but statistical significance was reached only in the swamp-rainforest habitat. The population abundance of the various species was not related to either their food habits or their ecological guild in any of the three study areas. The possible reasons explaining these patterns are discussed. In general, there is little congruence between our data and the popular 'energetic equivalence rule' hypothesis. [ABSTRACT FROM AUTHOR]

Snakes of the genus Psammophis are widespread in diverse habitats of west Africa, from dry savannas to moist rainforests. In southern Nigeria, P. phillipsi occurs with two 'forms', one with a divided cloacal shield (CSD) and one with an entire cloacal shield (CSE). These 'forms' were suggested to be possibly distinct species in a recent review by Hughes (1999). However, as no data are available on the variation in natural history, if any, between these two supposed species, we collected data on local distribution and natural history traits of these 'forms' in several localities of southern Nigeria. Out of 32 localities examined, sympatric CSD and CSE specimens occurred in 28.1% of the localities, CSD specimens alone occurred in 68.8%, and CSE specimens alone occurred in 3.1%. At five additional localities, where a higher number of specimens was examined (range 21-41 specimens), CSD specimens were clearly dominant over CSE specimens (on average 88.8% of specimens in each population), independently of the habitat types, and there was no apparent effect of longitude on the frequency of occurrence of CSD specimens. Both 'forms' proved to be habitat generalists (often inhabiting deforested areas and suburbs), and very similar in terms of type of prey eaten (mainly Agama lizards and Mabuya skinks, but also small mammals), and apparently also in terms of micro-habitats used for foraging (clearings into forested zones). Overall, there was no evident difference between these 'forms' in terms of the main ecological traits examined here. [ABSTRACT FROM AUTHOR]

The Niger Delta (Southern Nigeria) is the main oil-producing region in sub-Saharan Africa. Its biodiversity is very important for the concomitant presence of rainforests and mangroves, and many endemic flora and fauna. Six sites in southern Nigeria, four currently affected by oil industry development but formerly inside the rainforest belt and two in pristine protected areas, were surveyed for amphibians during 1996-2002, in both dry and rainy seasons. Amphibian species diversity was reliably assessed at all study sites, as shown by species accumulation curves. The total number of species found in the two pristine sites was much higher than that found in the four developed sites. Nevertheless, a total of over 6300 amphibian specimens belonging to 28 species were captured at these four sites. Species included three Bufonidae (genera Bufo and Nectophryne), two Pipidae (Silurana and Hymenochirus), nine Ranidae (Hylarana, Ptychadena, Aubria, Conraua, Hoplobatrachus, and Phrynobatrachus), one Arthroleptidae (Arthroleptis), one Rhacophoridae (Chiromantis), one Microhylidae (Phrynomantis), and eleven Hyperoliidae (Hyperolius, Afrixalus, Leptopelis, Phlyctimantis, and Opisthothylax). The four developed study sites were similar in terms of species composition; the most common species were Silurana tropicalis (accounting for about 74% of the total number of specimens captured), Bufo maculatus, Ptychadena spp., Hylarana albolabris, Hoplobatrachus occipitalis, Hyperolius cf. concolor and Afrixalus dorsalis. Greater numbers of species and individuals were captured in the rainy season than in the dry season. In terms of chemo-physical properties of the water at their breeding sites, both adult and larval anurans of several species (e. g., Silurana, Bufo and Ptychadena) were highly adaptable, being able to thrive in anoxic and slightly acidic water with dissolved oxygen from 0.50-1.50 mg l-1 and pH from 5.9-7.2. [ABSTRACT FROM AUTHOR]

The structure of the snake community was studied between 1996 and 2000 on a transect in the mangrove ecological zone of southern Nigeria, West Africa. In three major habitats, both taxonomical diversity and frequency of observations in relation to sampling effort were investigated. In general terms, the complexity of the snake community appeared less than in other habitats of the same geographic region (i.e. swamp forest and forest-plantation mosaics). In fact, only eighteen species were recorded, whereas 43 species are known to inhabit neighbouring habitats. A Principal Component Analysis allowed arrangement of the various species into two main groups in relation to the habitats of capture: (1) a group of species of rainforest biota (i.e. Toxicodryas blandingii, Thelotornis kirtlandii, Thrasops flavigularis, Rhamnophis aethiopissa, Gastropyxis smaragdina, Grayia smythii, Pseudohaje goldii, Python sebae), and (2) a group of species that, at least in Niger Delta, are typically linked to altered habitats, including derived savannas, plantations and suburbia (i.e. Psammophis cf. phillipsi, Philothamnus cf. nitidus, Hapsidophrys lineatus, Crotaphopeltis hotamboeia, Boaedon lineatus, Naja nigricollis, Python regius). The community structure in terms of food habits and body sizes appeared similar to those of other snake assemblages from different habitats of southern Nigeria. The conservation implications of our results are also discussed. [ABSTRACT FROM AUTHOR]

Describes the comparative feeding strategies and dietary plasticity of the sympatric cobras Naja melanoleuca and Naja nigricollis in three diverging habitats in Africa. Intersexual differences in prey composition and prey size; Accounts on the flexibility in prey-size patterns; Cause of intensive forest alteration and landscape modification.

The article presents a study which investigates the size-related habitat selection of Nile monitors (Varanus niloticus) in western Nigeria. The study was performed during 60-day surveys from May-June 2012 in the surrounding of Ibadan. The study recorded the type of habitat and the place of sighting of lizards. The results showed uneven percentage of habitat availability and lizard habitat selection.

Studies biological diversity patterns and conservation priorities of snake communities in moist rainforest and derived savanna sites of Nigeria. Comparison of the specific diversity and dominance index of snakes in forest and savanna areas; Species found in the forest and the savanna area; Conservation implication of biodiversity analyses; Danger of oil industry activities for snake communities.