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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]

Long-term ecological studies are important for understanding wild populations' dynamics and processes and the actual factors that can determine their decline. Here, we report the results of a 28-years-long (1992–2019) monitoring of three distinct populations of a tortoise, Testudo hermanni , in Central Italy, with an emphasis on their population abundance trends and on the eventual variation in their habitat use across years and among the study areas. Samplings were conducted by Visual Encounter Survey (VES) methodology, and using a suite of statistical analyses including correlations and Generalized Linear Models analyses. Our data showed a statistically significant decline in tortoise sightings through time, and concurrently also a variation in habitat use by tortoises. In all the three study areas, we observed a significant increase of tortoise sighting frequency in the habitat type characterized by high (>taller than 200 cm) shrubby and wooded vegetation. Since our analyses revealed no significant change in the habitat type availability by year in each study area, we suggest that T. hermanni was increasingly selecting closed vegetation spots throughout the years. We hypothesize that this observed trend of shift in habitat selection could be due to lowering their body temperatures to prevent overheating. So, the selection of more covered spots would be a thermal ecology adaptive consequence of the ongoing global warming. [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]

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 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.

Resource partitioning, the division of limited resources by species to help avoid competition, has been observed in freshwater turtle assemblages in several natural systems but has rarely been studied in tropical African ecosystems. Here, we investigate habitat preferences of two congeneric species in the family Pelomedusidae, Pelusios castaneus and P. cupulatta, in riverine/wetland habitats in the southern Ivory Coast (West Africa). Pelusios castaneus is a widespread species across West-central African savannahs and open forests, whereas P. cupulatta is endemic to the Upper Guinean forest region in West Africa. The two species have a similar diet composition (mainly carnivorous) but diverge considerably in body size, P. cupulatta being much larger. We use hand-fishing-nets and fishing funnel traps to record turtles in 18 distinct sites and analyze habitat preferences by species at two spatial scales. At a macro-habitat scale, P. castaneus is captured mainly in marshlands, whereas P. cupulatta is found in both rivers and wetlands. The two species differ significantly in their use of: (i) banks (P. castaneus being found primarily in spots with grassy banks, whereas P. cupulatta is found in spots with forested banks), and (ii) aquatic vegetation (P. cupulatta prefers spots with more abundant aquatic vegetation than P. castaneus), but both species select sites with no or moderate current. Additionally, in sites where P. cupulatta is not found, P. castaneus expands its spatial niche at multiple habitat scales, notably invading waterbodies with forested banks. Our results suggest that these two Pelomedusid turtle species potentially compete in the freshwater habitats in the southern Ivory Coast. [ABSTRACT FROM AUTHOR]

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. • habitat of Centrochelys sulcata is studied. • We employed field surveys and villager. • C. sulcata is widespread but declining. • Microhabitat preferences are evaluated at multiple spatial scales. • C. sulcata activity varies by season and daily time. [ABSTRACT FROM AUTHOR]

Tortoise ecology is poorly studied in East Africa. Here, using two terrestrial Testudinidae (Stigmochelys pardalis and Kinixys belliana) as study models, we (i) present basic demographic characteristics (sex-ratio, and density), (ii) describe correlates of their presence at two spatial scales (micro-habitat and macro-habitat), (iii) evaluate the effects of rainfall on their seasonal activity patterns, and (iv) analyze abundance patterns in relation to macro- and micro-habitat characteristics. We also describe an experiment, using tortoise shells, that can allow to control, and eventually correct, the reliability of observed data by taking into account the detectability of the study species in the wild. On the basis of a suite of statistical analysis and GIS-based elaborations, we confirmed, and further uncovered, the remarkable ecological differences existing between S. pardalis and K. belliana. The habitat use was different interspecifically, with K. belliana being much more linked to dense vegetation spots, often nearby waterbodies, whereas S. pardalis being an habitat generalist, at both micro- and macrohabitat scale. Nonetheless, juveniles of both species were observed in areas with significantly higher % soil covered by vegetation taller than 200 cm than adults of both sexes. This different habitat selection is hypothesized to be due to antipredatory reasons. Overall, our data suggests that interspecific competition should be minimal between these species. • A detection experiments using real shells was carried out. • Similar experimental approaches are suggested when studying tortoise habitat. • Two tortoises from South Sudan were studied. • The habitat use was different interspecifically at two spatial scales. • Conservation implications are presented. [ABSTRACT FROM AUTHOR]