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Greater cane rats (Thryonomys swinderianus) are important sources of bushmeat in southern Nigeria. Here, we collected and examined intestinal helminth parasites of these rats sold at Omagwa bushmeat market, Rivers State, Nigeria. Twelve intestinal tracts of T. swinderianus were purchased from December, 2020 to February, 2021, and transported to the laboratory for examination. Each sample was incised and its contents examined in 0.9% normal saline solution. Parasites encountered were washed in same solution, fixed in 70% ethanol and subsequently identified using taxonomical keys. Prevalence of infection was computed using standard formula for computing parasite ecological parameters. Four parasitic nematodes were isolated. Oesophagostomum venulosum and Strongylus sp. infected six hosts each accounting for a prevalence of 50.0%. Mean intensity of infection was about 12 parasites/infected host for O. venulosum and about 7 parasites/infected host for Strongylus sp. Trichuris paravispicularis had a prevalence of 33.3% and mean intensity of about two parasites/infected host, while Toxocara vitulorum was recovered as a single individual from one host at a prevalence of 8.3%. We conclude that T. swinderianus serves as host to intestinal nematode parasites, and recommend full parasitological investigation of the animal, where possible, to isolate and identify other helminth parasites not reported in the present research.

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.

The composition and structure of antelope assemblages were analyzed by using data from wild meat markets in three distinct study stations in the southern Niger Delta, Nigeria. The relative abundance of the different species coming into the markets was analyzed, and various diversity metrics were used to describe the different antelope communities. Sex ratios of these populations as well as the effect of season on the abundance of the various species in the markets were examined. It was observed that a single recently described species (Philantomba walteri) was the dominant species in the three localities, contributing about 70% of all the antelope individuals. The relatively low number of antelope carcasses observed in this study (less than the number of carcasses of small carnivores in the same sites) suggests that the ungulate fauna is already very depleted in the eastern Niger Delta region, with these mammals being hunted more intensely in the wet season.

Length-weight relationship and condition factor are essential parameters used in determination of growth and well-being of fish. The length-weight relationship and condition factor of eight species of cichlids were examined from a total of 358 cichlids belonging to fourteen species and seven genera. Sampling was between January and June, 2020 in Eniong River and lower Cross River in the Niger Delta from three stations: station one in Eniong river, station two at the confluence of Eniong and lower Cross River, and station three at the lower Cross River. The length and weight of each fish was measured to the nearest millimeter and gram, respectively. The length-weight relationship (LWR) and condition factor (K) of the species Coptodon dageti, Coptodon guineensis, Coptodon zilli, Chromidotilapia guntheri, Hemichromis elongatus, Oreochromis niloticus, Pelmatolapia mariae and Sarotherodon melanotheron were determined using standard methods. Total length of fish ranged from 12.9 ± 5.01 in H. elongatus to 20.7 ± 3.37cm in C. zilli. Total weight ranged from 24.8 ± 13.80 in H. elongatus to 146.4 ± 68.0 g in C. zilli. The exponent b ranged from 1.54 for H. elongatus to 3.34 in Pelmatolapia mariae. The coefficients of determination (r2) varied between H. elongatus (0.74) and O. niloticus (0.96). Fulton’s condition factor (K) ranged from 1.2 6 ± 0.50 (H. elongatus) to 1.89 ± 0.43 (O. niloticus). Length-weight relationship revealed negative allometry for six species and positive allometry for two species (O. niloticus and P. mariae). Cichlids in this study were observed to be in good condition, as the K values were greater than one.

This paper investigated the proximate, minerals and serum biochemistry in Hoplobatrachus occipitalis. The proximate and selected minerals of edible frog Hoplobatrachus occipitalis were determined using standard analytical methods. The result showed that crude protein was 16.91% carbohydrate was 1.76%, crude fibre 2.85%, The fat was 4.96% ash content was 1.84% and moisture was 71.67%. The selected mineral constituent recorded showed that sodium> iron> calcium > potassium > manganese. The nutritive serum biochemistry was determined in male and female species, the results revealed that both sexes have high nutritional profile suitable for human consumption; nevertheless, the female species have higher nutritional values than the males.

Little is known about fish diversity in the coastal streams south-eastern Nigeria in this world-renowned biodiversity hotspot. In these ecosystems, the combination of seasonal changes in hydrology as well as the presence of coastal forests provides a greater biotope diversity, food and shelter for many fish species. Currently, however, deforestation, pollution and exotic species invasions impact the system's hydrology, water quality ultimately changing fish assemblage composition. In this paper, we describe the current status of fish diversity in the forested coastal streams of south-eastern Nigerian based on recent collections and data drawn from selected scientific publications. We found a total of 88 fish species from 27 families in 10 orders. . Fish assemblages were generally characterised by a low evenness, with 90% of specimens belonging to over a quarter of the overall number of taxa, and strongly dominated by species of aquaculture interest, such as tilapiine cichlids. The studied stations had a high heterogeneity and non-comparable diversity profiles; stressing the role played by local conditions. Stations closer to the River Niger Delta differed significantly from the remaining large relatively homogeneous cluster. We found that the spatial turnover components of β-diversity were significant, and this was related to longitudinal distance, and not to species replacement by ecological vicariants. The observed species composition and the diversity patterns are consistent with a scenario whereby an originally high biodiversity is being eroded because of habitat degradation and the impact of alien species.

© 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.

1. A survey of eight local earthen hand-dug ponds located within the freshwater swamps of a Niger Delta area (southern Nigeria) was conducted over a period of 3 months. A total of 4,313 fishes representing 19 species from 12 families were recorded. 2. The most abundant species was Xenomystus nigri (905 individuals), whereas the least common was Protopterus annectens (13). Cichlidae and Clariidae counted three species each, whereas Anabantidae, Hepsetidae, Mochokidae, Protopteridae, Phractolaemidae, Malapteruridae and Gymnarchidae were represented by a single species each. 3. A lotic species, Synodontis sp., was recorded possibly as a result of the episodic flood of 2012. 4. The Engenni swamps harbour a moderately diverse ichthyofauna. Regulations should be put in place to further enhance the fisheries potential of these local ponds.

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.

Pelusios (Testudines: Pleurodira) is an Afrotropical endemic genus of freshwater turtles that have adapted to a variety of habitats, with savannahs and forests being their two main habitat types. Although considered generally carnivorous, these turtles have rarely been subjected to detailed field surveys for determining their quantitative diet. In this paper, by using both the literature and original data, we analyze the diet of several Pelusios populations: three P. adansonii populations from South Sudan, one P. nanus from Zambia, seven P. castaneus from Nigeria, Benin and Togo, and four P. niger from Nigeria. All species were omnivorous but with a clear preponderance of the prey items being of animal origin (e.g., amphibians, fish, arthropods and annelids). Saturation curves revealed that the diet composition of all the surveyed populations was adequately assessed, and the diversity profiles indicated that all the populations were relatively similar in terms of overall dietary diversity. General Linear Models (GLM) showed a negative effect of vegetation cover on Anura adult consumption by turtles, and showed that the frequencies of Anura tadpoles, fish, reptiles and birds on Pelusios diets increased with the increase in vegetation cover. The GLM model also showed positive effects of individual body size on algae, Bivalvia, reptiles, birds and small mammal consumption by turtles, and underlined that the predation on Arachnida decreased with the increase in turtle body size. In all species, there were no significant intersexual dietary differences, whereas there were substantial ontogenetic dietary changes in three out of four species. Small-sized individuals of P. castaneus, P. niger and P. adansonii tended to feed mainly upon insects, with the adults also taking many fish and adult frogs, and in the case of P. niger, also birds and small mammals. Conversely, in P. nanus, the diet composition did not vary substantially from the juvenile to the adult age. All species appeared substantially generalist in terms of their diet composition, although the effects of season (wet versus dry) were not adequately assessed by our study.

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). In addition, we interviewed fishers in the Lake Volta area to explore their perception about turtle abundance trends. Overall, 210 turtle individuals belonging to four species (Trionyx triunguis, Cyclanorbis senegalensis, Pelomedusa sp. and Pelusios castaneus) were recorded; for 139 individuals the precise capture sites and habitat type were recorded, whereas 71 individuals were observed in market places and were not considered in our analyses. We observed three sympatric species at the local scale of the various study sites. In each site, the dominant species was either C. senegalensis or Pelomedusa sp. However, Pelomedusa sp. was the most abundant species in temporary waterbodies whereas C. senegalensis was more numerous in permanent ones. A Multiple Correspondence Analysis visualized that, in permanent waterbodies all species were associated with similar physical habitat variables. C. senegalensis and T. triunguis were more abundant in localities containing woody emergent vegetation and inorganic substrate. In a Canonical Correspondence Analysis, we show that the density of herbaceous emergent vegetation was more important for P. castaneus than for C. senegalensis. Interviews with local people suggested that freshwater turtles do not have any special marketing interest for them, but that overfishing may have considerably affected the population density of these semiaquatic reptiles. Overall, Comparisons of diversity metrics between our study areas and previous literature revealed that turtle community composition was substantially the same, both qualitatively and quantitatively, all throughout the savannahs of West Africa.

Pelusios is an Afrotropical endemic genus of freshwater turtles that have adapted to a variety of habitats, with savannahs and forests being their two main habitat types. Although considered generally carnivorous, these turtles have rarely been subjected to detailed field surveys for determining their quantitative diet. In this paper, by using both literature and original data, we analyse the diet of several Pelusios populations: three P. adansonii populations from South Sudan, one P. nanus from Zambia, seven P. castaneus from Nigeria, Benin and Togo, and four P. niger from Nigeria. All species were omnivorous but with a clear preponderance of the prey items being of animal origin (amphibians, fish, arthropods and anellids). Saturation curves revealed that the diet composition of all the surveyed populations was adequately assessed, and the diversity profiles indicated that all the populations were relatively similar in terms of overall dietary diversity. General Linear Models (GLM) showed a negative effect of vegetation cover on Anura adults consumption by turtles, while showed that the frequencies of Anura tadpoles, fish, reptiles and birds on Pelusios diets increased with the increase of vegetation cover. The GLM model also showed positive effects of individual body size on algae, Bivalvia, reptiles, birds and small mammals consumption by turtles, while underlined that the predation on Arachnida decreased with the increases of turtles body size. All species appeared substantially generalists in terms of their diet composition, although the effects of season (wet versus dry months) were not adequately assessed by our study.

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.

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.

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.

Throughout Africa, feelings towards crocodiles vary according to the danger or fear experienced by communities living alongside them. Crocodile conservation programmes 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, with 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).

Venomous snakes are among the main sources of mortality for humans in rural regions, especially in tropical countries. In this study, a meta-analysis of quantitative community ecology studies on snake assemblages throughout the world was conducted in order to evaluate variation in the frequency of occurrence of venomous species and venomous individuals by habitat and continent. A bibliographic search was done by consulting &ldquo, Google Scholar&rdquo, and &ldquo, ISI Web of Knowledge&rdquo, In total, 24,200 results were obtained from our bibliographic search, out of which 60 independent studies reporting raw and analyzable quantitative data from 81 distinct snake communities were retained and used for analyses. A snow-ball procedure was also used to uncover additional studies to include in the analyses. We gathered data on a total of 30,537 snake individuals, with an average of almost 30% of venomous individuals. The mean number of sympatric species was 19, whereas the mean number of sympatric venomous species was almost 5. Venomous snake species accounted for 24.4% of the total species in each community&mdash, almost the same as the overall percentage of venomous snake species known worldwide (about 24%). The frequency of occurrence of venomous individuals did not differ significantly between tropical and temperate snake communities, and the same was true for the frequency of venomous species within each community. Thus, the greater number of snakebites in tropical countries is not due to there being more venomous snake species or individuals. The total number of species and the number of venomous species observed in each community were positively correlated, and there was a significant difference among continents in terms of the mean number of species in each community. Within communities, there were inter-continental and inter-habitat differences in both the percentage of venomous species and in the percentage of venomous individuals. The Generalized Linear Model (GLM) revealed that the frequency of venomous species at a local scale depended only on the total number of species inhabiting a given site, whereas the frequency of venomous individuals within communities depended on both the total number of species and a habitat&ndash, continent interaction. Our meta-analysis could enable the appropriate authorities/agencies to take the relative abundance of venomous species/individuals within snake assemblages into consideration for a better positioning of the first aid centers in locations where snake antivenoms should be available.

Temperature profoundly influences the biology of ectotherm organisms, for example reptiles, which mostly regulate their body temperature behaviorally by shuttling between heat sources and sinks. The thermal quality of the environment directly affects the amount of time that a reptile takes to keep the body temperature within the optimal range. The foraging strategy of reptiles is often correlated to the thermoregulatory strategies. Depending on their foraging strategy, carnivorous reptiles can be high-energy consumers (active foragers) or low-energy consumers (ambush foragers). Our study allowed to get insights into basking versus non-basking behaviors of (i) snakes belonging to two different families (eight viperids and four elapids) with contrasted life-styles by either field or captive observations, (ii) free-ranging snakes (n = 3245) inhabiting contrasted habitats (forest versus savannah), and (iii) captive snakes (n = 4) outside the feeding activity and during digestion phase. We observed a tendency to spend more time in thermoregulation in the viperids than in the elapids and this pattern were consistent between field and experimental observations. We suggest that the higher basking activity of viperids is correlated to their predominantly nocturnal and ambush habits compared to the diurnal and active-foraging habits of the elapids. We also observed an effect of the thermal environmental quality with the savannah species tending to bask less than forest species. As for postprandial termophily, viperids showed a longer postprandial basking time than elapids even if all the snakes in the captivity sample were fed identically in terms of prey type and relative prey mass. Conservation insights related to the observed pattern are also provided.

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.

Understanding age-dependent mortality processes is a critical challenge for population biologists. Actuarial senescence appears to be a common process across the tree of life. Senescence patterns are highly variable in pluricellular organisms: senescence can be gradual or sharp and its onset may be early or delayed. By contrast, studies revealed that organisms may also not experience senescence at all while others display a “negative senescence”; i.e. a decrease of mortality rate with age. To date, studies on senescence have largely focused on human and other endotherm vertebrates, limiting our understanding of senescence in amniotes as a whole. By contrast, few have examined the diversity of senescence patterns in ectotherm vertebrates as reptiles. Here, we examined population dynamics and age-dependent mortality patterns in three tropical tortoises (Kinixys erosa, Kinixys homeana, Kinixys nogueyi) and snakes (Bitis gabonica, Bitis nasicornis, Causus maculatus). Our study revealed that tortoises ofKinixysgenus had a higher survival and a lower recruitment than snakes of the generaBitisandCausus, indicating that they have a slower life history. Furthermore, we showed that survival more slowly decreased with age in tortoises than in snakes. In addition, we highlighted contrasted patterns of age-dependent mortality in the three genera. InKinixys, the relationship between mortality rate and age was positive and linear, suggesting gradual senescence over tortoise lifetime. By contrast, the relationship between mortality rate and age was negative and sharp inBitisandCausus, possibly due to a “negative senescence” starting early in life. Our study highlighted various age-dependent mortality patterns in tropical reptiles. It also contributed to extend our knowledge of senescence in ectotherm vertebrates whose the demography is still poorly understood. In addition, while negative senescence has never been reported in endotherm vertebrates, our results showed that it can be common phenomenon in ectotherms.

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 have been well studied, non-wealth correlates have been poorly considered. Here, we analyse how variables such as age and gender may 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 2453 persons (1253 urban, 1200 in rural areas) to determine frequency of consumption of bushmeat as well as the 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 were 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.

Ebola virus disease, EVD, has been linked with wild meat. In Nigeria, strict restrictions on wild meat sales were applied after the first case in July 2014. We quantified wild meat trade in nine markets in southern Nigeria, during Oct. 2010 – Dec. 2019, and undertook consumer interviews during 2018–2019. Wild meat sales fell to low levels between during EVD (Jul. - Oct. 2014), after which Nigeria was declared Ebola-free. Prior to EVD (2012–2014), reptile carcass numbers declined markedly, collapsed during EVD, but rebounded immediately post-EVD until 2017 to values exceeding pre-EVD (especially true for turtles and tortoises). Reptile consumption increased as mammal numbers declined. After 2017, reptile numbers fell and remained low until the end of the study, indicating population collapses and depletion. Fruit bats and primates did not recover after EVD, but ungulates, rodents and carnivores increased significantly after EVD though never reached pre-EVD levels. Interviews revealed strong rural versus urban and age-specific differences regarding wild meat consumption and attitudes. Most people worried about Ebola and more than half of interviewees agreed that wild meat poses a transmission risk. Except urban males, over-60-year olds were least informed about the Ebola risk of wild meat, indicating that any future behavioural change campaign should focus on the younger age classes. Unlike other studies, our research clearly shows that changes in purchasing behaviour of consumers and education campaigns were effective in reducing the trade of bats and primates, animal groups likely to be implicated in the transmission of Ebola.

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.

Helminths are common parasitic fauna of goats. This study was aimed at identifying and quantifying the gastrointestinal helminth parasites of Red Sokoto goats slaughtered at Trans-Amadi and Rumuokoro abattoirs, Rivers State, Nigeria. Fifty intestinal tracts were examined at each location accounting for a total of 100 samples from both locations. Samples were weighed and dissected; direct microscopy was used to examine samples for adult helminths and test-tube floatation technique was used to examine organic matter from samples for parasite eggs. Nematodes were identified using keys and fixed in 70% alcohol. Prevalence and mean intensity of infection were computed; product moment correlation and Student t-tests were used for statistical analysis. Two nematode parasites were identified- Haemonchus contortus and Trichuris ovis . In Trans Amadi, prevalence and mean intensity of infection were 46.0% and 13 parasites/infected host, respectively for H. contortus , and 54.0% and 11 parasites/infected host for T. ovis . In Rumuokoro, prevalence of 38.0% and 52.0% were computed for H. contortus and T. ovis , respectively, while the mean intensity were 6 and 8 parasites/infected host, respectively for H. contortus and T. ovis . Single infection with Trichuris ovis was higher (30% Trans Amadi; 34% Rumuokoro) than either single infection with H. contortus or double infection with both parasites. There was a significant correlation between the parasite burden and intestinal mass at Trans-Amadi (r 48 =0.33, P 0.05 =0.279), but not at Rumuokoro (r 48 =0.10, P 0.05 =0.279). The total prevalence and prevalence of single and double infection at both locations did not differ significantly (t 3 =0.93, p=0.21). Agricultural extension and meat inspection services should be carried out regularly to educate farmers on the symptoms, impacts, treatment and management of helminth parasites.

Bushmeat consumption in large Sub-Saharan African cities is perceived as a major threat to the conservation of many species because their considerable population sizes can generate a significant demand for bushmeat. The study of the effect of age, sex and geographic location in bushmeat eating in African cities may offer valuable insights on which population groups to target in behaviour change campaigns. Using 2,040 interviews in six West African cities from four countries, in forest and savannah settings, we analysed the differences between age and sex in people’s frequency of bushmeat consumption. Overall, we found similar patterns in all sampled cities. As many as 62.2 % males and 72.1% females replied that they ‘would not eat bushmeat at all’, though only 12.8% males and 8.8% females mentioned they regularly ate bushmeat. Younger generations of both sexes answered that they ‘would never eat bushmeat’ more often than older age groups, independently of their city of origin. These trends are encouraging though further research needs to be undertaken to find out whether bushmeat volumes consumed in cities are unsustainable and having a serious impact of prey populations.

The interactive-versus-isolationist hypothesis predicts that parasite communities should be depauperated and weakly structured by interspecific competition in amphibians. A parasitological survey was carried out to test this hypothesis using three anuran species from Nigeria, tropical Africa (one Bufonidae; two Ranidae). High values of parasite infection parameters were found in all three species, which were infected by nematodes, cestodes and trematodes. Nonetheless, the parasite communities of the three anurans were very depauperated in terms of number of species (4 to 6). Interspecific competition was irrelevant in all species, as revealed by null models and Monte Carlo permutations. Cluster analyses revealed that, in terms of parasite community composition, the two Ranidae were similar, whereas the Bufonidae was more different. However, when prevalence, intensity, and abundance of parasites are combined into a multivariate analysis, each anuran species was clearly spaced apart from the others, thus revealing considerable species-specific differences in terms of their parasite communities. All anurans were generalists and probably opportunistic in terms of dietary habits, and showed no evidence of interspecific competition for food. Overall, our data are widely consistent with expectations driven from the interactive-versus-isolationist parasite communities hypothesis.

The African spurred tortoiseCentrochelys sulcatais 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.

The Niger Delta (southern Nigeria) is a crucial region for biodiversity because it is (i) part of the West African forests hotspot, (ii) under considerable threats because of habitat devastations, and (iii) a minor centre of endemism for many faunal and floral groups. In this paper, we analyze the communities of mammals (excluding bats, shrews and murids) occurring in all vegetation zones of the region, using both original field data (direct sightings of live animals, bushmeat market specimens, skins, skulls, bones, tracks, reliable interviews) collected in 1996-2015 and literature data. We also explore the main drivers of community structure by using a suite of multivariate (cluster) and null models (co-occurrence) analyses, and the conservation consequences of our data. A total of 45 extant species was found; their ecological distribution was uneven across vegetation zones, with flood forest, marsh forest and eastern flank forests housing more species. Although most species were widespread, 33.3 % had narrow ecological preferences. Cluster analysis confirmed that the community composition was (i) similar in habitats that were suspected to derive from pristine flood forests, and that (ii) the mammal assemblages were different in the two sides of the River Niger main axis. The endemic rate was low (4.44 % of the species), with one endemic species for each of the two sides of the Niger Delta. Twenty-one species were uncertain to occur in the study area, with a few being extinct (for instance, Choeropsis liberiensis). Co-occurrence models excluded that a competitively structured community of species is assembled in each of the vegetation zones, and cluster analyses suggested that biogeographic pressures may be important. 24.4 % of the extant species are globally threatened by IUCN, with one being Endangered (Pan troglodytes) and one Critically Endangered (Piliocolobus epieni). Flood forest and Eastern Flank forest represented the main vegetation zones inhabited by threatened species. In order to preserve the mammal community of the Delta, it is essential to carefully conserve flood and marsh forest patches, but also barrier island forests that still house highly threatened mammal populations.

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 niger Gray, 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, and Pan troglodytes (Blumenbach, 1775)). Diversity-dominance diagrams showed that the evenness profiles were simila...

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.

Using questionnaire surveys in southern Nigeria, this paper explores whether : (i) bushmeat is still a crucial source of animal protein for local communities ; (ii) is still culturally very relevant ; and (iii) if people value differently the various kinds of bushmeat species because of customer preferences. In addition, this paper provides information on whether (iv) the bushmeat trade locally depletes target game species ; and (v) whether the disappearance of large animals from the markets would indicate their local extirpation from the wild. A combination of interviews was carried out with both men and women of different age classes including hunters, consumers and sellers, from different Nigerian locations with different habitat conditions, socio-economic and ethnic characteristics. Results of these interviews suggest that the consumption of bushmeat has little subsistence value, especially in urban areas, except for a small sub-section of the community. Indeed, even in rural areas less than 30 % of the interviewees of less than 50 years age answered that they frequently eat bushmeat. Cultural importance of bushmeat decreased substantially in recent years , as shown by that (i) this food source was quickly abandoned by people during the 2014 Ebola crisis, and (ii) most of questionnaire respondents affirmed that they would have eaten bushmeat only rarely or even not at all. There was support for the notion that the price of a carcass was mainly determined by the animal size and not by the consumer preference. Bushmeat utilization and trade may certainly deplete target animal species at the local scale. Nonetheless, there is still no sufficient empirical evidence for the notion that, when large animals disappeared from the markets, it meant that their populations were heavily depleted or even extinct. Indeed, based on cultural elements highlighted by interviewed hunters, there is evidence that this notion may be wrong, at least in the richest and economically more dynamic regions of West Africa. It is advised that bushmeat studies should explore more in depth the cultural flexibility of human communities before drawing generalized conclusions, thus avoiding unsupported large-scale conclusions based on data collected at a very small spatial scale and during short time periods., La viande de brousse : des enquêtes révèlent des points de controverse sur la dynamique de son commerce au Nigéria Sur la base d’enquêtes dans le sud du Nigéria, cet article examine (i) si la viande de brousse est toujours une source cruciale de protéines pour les communautés locales, (ii) si elle est toujours culturellement bien justifiée et (iii) si, selon les préférences des consommateurs, des valeurs différentes sont attribuées aux divers types d’espèces constituant cette viande de brousse. De plus, cet article fournit des informations sur la question de savoir (iv) si le commerce de la viande de brousse épuise localement les populations des espèces ciblées, et (v) si la disparition sur les marchés de grands animaux est signe de leur extermination locale. Une combinaison d’entretiens avec des hommes et des femmes de différentes classes d’âge, incluant des chasseurs, consommateurs et vendeurs, a été conduite dans divers localités nigérianes correspondant à différentes conditions d’habitat et de caractéristiques socio-économiques et ethniques. Les résultats suggèrent que la consommation de viande de brousse, en particulier dans les zones urbaines, n’a pas une grande valeur de subsistance, sauf pour une petite sous-section de la communauté. De fait, même dans les zones rurales, moins de 30 % des personnes de moins de 50 ans interrogées ont répondu consommer fréquemment de la viande de brousse. L’importance culturelle de la viande de brousse a substantiellement diminué dans les années récentes, comme en témoigne le fait que (i) cette source de nourriture a été rapidement abandonnée durant la crise d’Ebola en 2014 et (ii) la plupart des personnes interrogées ont affirmé n’en manger que rarement voire pas du tout. Les données recueillies vont dans le sens de ce que le prix d’une carcasse serait principalement déterminé par la taille de l’animal et non pas par la préférence des consommateurs. L’utilisation et le commerce de la viande de brousse peuvent certainement épuiser localement les populations des espèces animales ciblées. Néanmoins, il n’y a toujours pas suffisamment de preuves empiriques de la notion selon laquelle quand les grands animaux disparaissent des marchés cela signifierait que leurs populations auraient été considérablement épuisées voire exterminées. De fait, sur la base d’éléments culturels exposés par les chasseurs interrogés, il semblerait que cette notion soit erronée, du moins en ce qui concerne les régions ouest-africaines les plus riches et les plus économiquement dynamiques. Il est conseillé à ceux qui étudient la viande de brousse d ’ explorer plus en profondeur la flexibilité culturelle des communautés humaines avant de généraliser des conclusions, évitant ainsi d’extrapoler à grande échelle des conclusions insuffisamment fondées car basées sur des données collectées à très petite échelle spatiale et durant de courtes périodes de temps., Luiselli Luca,Petrozzi Fabio,Akani Godfrey C.,Di Vittorio Massimiliano,Amadi Nioking,Ebere Nwabueze,Dendi Daniele,Amori Giovanni,Eniang Edem A. Rehashing bushmeat – interview campaigns reveal some controvrsia about the bushmeat trade dynamic in Nigeriain. In: Revue d'Écologie (La Terre et La Vie), tome 72, n°1, 2017. pp. 3-18.

In this study, the sex ratio, habitat use, and diet of free-ranging Kinixys nogueyi are 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.

The study of community composition shifts due to increased habitat modifications and deforestation is a primary issue in contemporary tropical community ecology theory. As the forest habitat conversion process has been very short in Africa relative to the evolutionary temporal scale, it is likely that animal communities are not at an equilibrium. The Upper OrashiForest Reserve(NigerDelta regionofSouthern Nigeria) is a valuable case study as it is one of the few remnant deltaic swamp forest patches inside a highly developed and deforested region. In this paper, we investigated some aspects of the community ecology of reptiles of thisforestareabasedonstandardizedfieldsurveysacross26 study plots. Overall, we recorded 34 species, with the detected number of both species (34 versus 27) and individuals (562 versus 381) being higher during the wet season. Diversity/dominance diagrams showed similar trends in both seasons, but diversity measures showed that evenness was remarkably higher by wet season. Analysis of similarities (ANOSIM) confirmed that the species-richness estimate generated by Chao’s index was significantly higher for the wet season. However, the profiles of the diversity curves were comparable in the two seasons. The proportion of forest-specialist species decreased compared to that observed at the same study area 15+ years ago, with a gradual process of biotic homogenization being apparent.

Assemblage structure, diversity measures and diversity/dominance patterns of snakes were studied between 1996 and 2013 in three types of plantation in the Niger River delta of southern Nigeria. The investigated plantation types were pineapple, banana/plantain, and cassava/yam. Over 74% of the census species (n = 27) were found in all three plantation types, with, overall, just two singletons (Bitis nasicornis, Lamprophis olivaceus) being observed. Despite an overall similarity in the taxonomic species composition, a principal component analysis placed the three plantation types in distinct zones of the multivariate space. Diversity/dominance diagrams for the three plantation types showed that banana/plantain and cassava/yam were nearly identical in terms of evenness profile, whereas the pineapple plantation had a higher evenness.

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.

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 30 000 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;Leptotyphlopscfr.sundewalli).

To better understand the habitat preferences of the African spurred tortoise (Centrochelys sulcata), we tested possible associations between their distribution and land use, vegetation cov...

Ebola virus effects on the bushmeat trade in West Africa Godfrey C. Akani, Daniele Dendi and Luca Luiselli* Niger Delta Ecology and Biodiversity Conservation Unit, Department of Applied and Environmental Biology, Rivers State University of Science and Technology, Port Harcourt (Rivers State), P.M.B.5080, Nigeria, Associazione Centro ELIS, via Sandro Sandri 79, Rome, 00182, Italy and Centre of Environmental Studies Demetra, via Olona 7, Rome, 00198, Italy