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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.
Suleman B. Gbewaa; S. Kobby Oppong; Brian D. Horne; Paul Tehoda; Fabio Petrozzi; Daniele Dendi; Godfrey C. Akani; Massimiliano Di Vittorio; Stephanie N. Ajong; Nic Pacini; Julia E. Fa; Luca Luiselli. Community Characteristics of Sympatric Freshwater Turtles from Savannah Waterbodies in Ghana. Wetlands 2021, 41, 1 -13.
AMA StyleSuleman B. Gbewaa, S. Kobby Oppong, Brian D. Horne, Paul Tehoda, Fabio Petrozzi, Daniele Dendi, Godfrey C. Akani, Massimiliano Di Vittorio, Stephanie N. Ajong, Nic Pacini, Julia E. Fa, Luca Luiselli. Community Characteristics of Sympatric Freshwater Turtles from Savannah Waterbodies in Ghana. Wetlands. 2021; 41 (5):1-13.
Chicago/Turabian StyleSuleman B. Gbewaa; S. Kobby Oppong; Brian D. Horne; Paul Tehoda; Fabio Petrozzi; Daniele Dendi; Godfrey C. Akani; Massimiliano Di Vittorio; Stephanie N. Ajong; Nic Pacini; Julia E. Fa; Luca Luiselli. 2021. "Community Characteristics of Sympatric Freshwater Turtles from Savannah Waterbodies in Ghana." Wetlands 41, no. 5: 1-13.
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.
Luca Luiselli; Gift Demaya; John Benansio; Fabio Petrozzi; Godfrey Akani; Edem Eniang; Stephanie Ajong; Massimiliano Di Vittorio; Nioking Amadi; Daniele Dendi. A Comparative Analysis of the Diets of a Genus of Freshwater Turtles across Africa. Diversity 2021, 13, 165 .
AMA StyleLuca Luiselli, Gift Demaya, John Benansio, Fabio Petrozzi, Godfrey Akani, Edem Eniang, Stephanie Ajong, Massimiliano Di Vittorio, Nioking Amadi, Daniele Dendi. A Comparative Analysis of the Diets of a Genus of Freshwater Turtles across Africa. Diversity. 2021; 13 (4):165.
Chicago/Turabian StyleLuca Luiselli; Gift Demaya; John Benansio; Fabio Petrozzi; Godfrey Akani; Edem Eniang; Stephanie Ajong; Massimiliano Di Vittorio; Nioking Amadi; Daniele Dendi. 2021. "A Comparative Analysis of the Diets of a Genus of Freshwater Turtles across Africa." Diversity 13, no. 4: 165.
Habitat modification is a major factor in the decline of reptile populations. The degree of the decline has been shown to be directly related to the intensity of habitat modification. Farming practices and urbanization are just two of the factors involved indicating that the development of practices that minimize or cancel anthropogenic impacts is urgently needed to prevent further declines. This requires knowledge of population ecology of reptiles in both disturbed and pristine habitats. In this paper, we describe aspects of green lizard (Lacerta bilineata) population ecology in a forest–pasture relatively pristine mosaic habitat in central Italy and a fragmented habitat in western France. In Italy, habitat niche overlap was very high between males and females but very low between males and juveniles. For male and female abundances, general linear models showed that the adult abundances increased with the increase of Rubus bushes, whereas juvenile abundance increased with the increase of Spartium bushes. Contingency table analysis showed that juveniles were also much more frequently observed in grasslands than adults of either sexes. The observed ontogenetic structural niche pattern was likely due to intraspecific competition avoidance, competition interference, and cannibalism. The persistence of the same patterns across years demonstrates a temporal stability of the ontogenetic structural niche pattern. Over the length of the study period, population densities were stable in the Italian population, but densities were much higher by around five times in the hedgerow in the fragmented habitat in France. In the hedgerow, monthly lizard presence was uneven, with the greatest number of sightings in June and July. Overall, our study provided no support for the notion that lizard abundance/density should be lower in modified compared to unmodified habitats, and clearly revealed that a careful management of the hedgerows is crucial for the conservation of this lizard species in agro-forest ecosystems.
Lorenzo Rugiero; Massimo Capula; Massimiliano Di Vittorio; Daniele Dendi; Roger Meek; Luca Luiselli. Ontogenetic Habitat Use and Density of the Green Lizard (Lacerta bilineata) in Contrasted Landscapes in France and Italy. Conservation 2021, 1, 1 -16.
AMA StyleLorenzo Rugiero, Massimo Capula, Massimiliano Di Vittorio, Daniele Dendi, Roger Meek, Luca Luiselli. Ontogenetic Habitat Use and Density of the Green Lizard (Lacerta bilineata) in Contrasted Landscapes in France and Italy. Conservation. 2021; 1 (1):1-16.
Chicago/Turabian StyleLorenzo Rugiero; Massimo Capula; Massimiliano Di Vittorio; Daniele Dendi; Roger Meek; Luca Luiselli. 2021. "Ontogenetic Habitat Use and Density of the Green Lizard (Lacerta bilineata) in Contrasted Landscapes in France and Italy." Conservation 1, no. 1: 1-16.
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.
Gift Simon Demaya; John Sebit Benansio; Fabio Petrozzi; Massimiliano Di Vittorio; Daniele Dendi; John E. Fa; Luca Luiselli. Habitat use and spatial niche overlap of sympatric savannah tortoises at multiple spatial scales in South Sudan. Journal of Arid Environments 2020, 183, 104287 .
AMA StyleGift Simon Demaya, John Sebit Benansio, Fabio Petrozzi, Massimiliano Di Vittorio, Daniele Dendi, John E. Fa, Luca Luiselli. Habitat use and spatial niche overlap of sympatric savannah tortoises at multiple spatial scales in South Sudan. Journal of Arid Environments. 2020; 183 ():104287.
Chicago/Turabian StyleGift Simon Demaya; John Sebit Benansio; Fabio Petrozzi; Massimiliano Di Vittorio; Daniele Dendi; John E. Fa; Luca Luiselli. 2020. "Habitat use and spatial niche overlap of sympatric savannah tortoises at multiple spatial scales in South Sudan." Journal of Arid Environments 183, no. : 104287.
Reed bed ecosystems are crucial for the survival of complex animal communities in Europe and Western Asia, but have been subjected to considerable decline, especially in beds in eutrophic shallow lakes, throughout Europe during the last decades. In Western Asia, however, these ecosystems are still wide and ecologically intact, and support highly biodiverse communities of species, including some highly threatened taxa. Here, we studied the spatio-temporal community dynamics of semi-aquatic reptiles in a wide reed bed biotope in Azerbaijan, and present conservation considerations for its optimal management for the survival of the authochtonous reptile species. Three reptile species (two snakes, Natrix natrix and Natrix tessellata, and one turtle Emys orbicularis persica) were found in the study area. Activity intensity was not even throughout the years, and was significantly more related to ambient temperatures in 2016 than in 2017. Interestingly, amphipod abundance was also significantly different between years, and correlated well with the differences in activity patterns observed in a turtle species. There were complex spatio-temporal patterns exhibited by the reptile species at the study area, with an excess of reptile individuals in the high density reed bed habitat during summertime whereas there was an excess of individuals in the open reed bed habitat in spring and autumn. This evidence suggests that there should be seasonal interhabitat movements of reptiles at the study area, and that the reed beds are not perceived as a homogeneous habitat by reptiles. Several hypotheses are presented to explain these unexpected spatio-temporal patterns by reptiles in reed beds. Our study clearly shows that, in order to enhance the conservation of reptiles, it is important to keep a mosaic of areas with dense reed stands (high density of young stems) and of open reed stands (lower density of older stems), thus increasing habitat heterogeneity and favouring small-scale ecological key-structures.
Luca Luiselli; Massimiliano Di Vittorio; Corrado Battisti; Stephanie Nwanefulu Ajong. Spatio-Temporal Dynamics of a Semi-Aquatic Reptile Community in Caspian Reed Bed Ecosystems. Wetlands 2020, 40, 2527 -2537.
AMA StyleLuca Luiselli, Massimiliano Di Vittorio, Corrado Battisti, Stephanie Nwanefulu Ajong. Spatio-Temporal Dynamics of a Semi-Aquatic Reptile Community in Caspian Reed Bed Ecosystems. Wetlands. 2020; 40 (6):2527-2537.
Chicago/Turabian StyleLuca Luiselli; Massimiliano Di Vittorio; Corrado Battisti; Stephanie Nwanefulu Ajong. 2020. "Spatio-Temporal Dynamics of a Semi-Aquatic Reptile Community in Caspian Reed Bed Ecosystems." Wetlands 40, no. 6: 2527-2537.
Few studies are available on the population dynamics of medium and large mammals in gallery forests of the Sudan and Sahel regions of West Africa. Line-transect studies of the abundance (estimated by KIA) of nine species of ungulates and three species of primates were carried out between 2004 and 2013 in the Comoé-Leraba protected area of Burkina Faso, West Africa. No peer-reviewed study of population sizes of mammals in this protected area has been published, making the data presented of special relevance. Population size trends varied significantly across years in both primates and ungulates, with some species (Papio anubis, Phacochoerus africanus, Alcelaphus busephalus and Tragelaphus scriptus) decreasing consistently. Significant relationships were observed between poaching intensity and population oscillations in Erythrocebus patas, Kobus ellipsiprymnus, Kobus kob, Ourebia ourebi and Cephalophus rufilatus.
Emmanuel M. Hema; Yaya Ouattara; Mamadou Karama; Fabio Petrozzi; Massimiliano Di Vittorio; Wendengoudi Guenda; Luca Luiselli. Population dynamics of medium and large mammals in a West African gallery forest area and the potential effects of poaching. Journal of Threatened Taxa 2017, 9, 10151 .
AMA StyleEmmanuel M. Hema, Yaya Ouattara, Mamadou Karama, Fabio Petrozzi, Massimiliano Di Vittorio, Wendengoudi Guenda, Luca Luiselli. Population dynamics of medium and large mammals in a West African gallery forest area and the potential effects of poaching. Journal of Threatened Taxa. 2017; 9 (5):10151.
Chicago/Turabian StyleEmmanuel M. Hema; Yaya Ouattara; Mamadou Karama; Fabio Petrozzi; Massimiliano Di Vittorio; Wendengoudi Guenda; Luca Luiselli. 2017. "Population dynamics of medium and large mammals in a West African gallery forest area and the potential effects of poaching." Journal of Threatened Taxa 9, no. 5: 10151.
The presence of the lanner falcon Falco biarmicus feldeggi in Sicily was modelled by generalized linear models using climatic, topographic, ecological and land-use variables at both the landscape (UTM cells of 10 × 10 km) and the home range (12.56 km2) spatial scales. At the landscape scale, a significant spatial autocorrelation of the lanner population, corresponding to the longitudinal distribution of sites, was found, with the species occurring within the most xeric UTM cells. There was also a negative relationship between falcon presence and potential evapo-transpiration values, either in the coldest months or throughout the year. The same negative relationship was also seen with the surfaces of CORINE artificial areas, thus showing that the species has a low tolerance to any anthropogenic landscape. At home range scale, our predictive models revealed a preference for territories with steep slopes surrounded by natural grassland, sclerophyll vegetation, arable land and agricultural land. The lack of spatial correlation and the identification of specific preferred land use classes, suggests that the home range scale is more appropriate than the landscape scale for predicting the occurrence of lanner falcons. The maintenance of a stable lanner falcon population in Sicily should be addressed at both small and large scales. Se estimó la presencia del halcón borní Falco biarmicus feldeggi en Sicilia mediante modelos lineales generalizados utilizando variables climáticas, topográficas, ecológicas y de uso del suelo a escalas tanto del paisaje (cuadrículas UTM de 10 × 10 km) como de áreas de campeo (12,56 km2). A escala paisajística se encontró una autocorrelación espacial significativa en la población de halcones, que correspondió a una distribución longitudinal de los sitios, presentándose la especie en las cuadrículas UTM más áridas. También hubo una relación negativa entre la presencia del halcón y los valores de evapo-transpiración, tanto en los meses más fríos como durante todo el año. Esa misma correlación también se obtuvo con las superficies de áreas artificiales CORINE, lo que muestra la baja tolerancia de la especie a paisajes transformados por el hombre. A escala de áreas de campeo los modelos revelaron preferencias por territorios con pendientes empinadas rodeadas por pastizales naturales, vegetación esclerófila y campos agrícolas. La falta de correlación espacial y la individualización de usos específicos de la tierra sugiere que la escala de área de campeo es más apta que la de paisaje para predecir la presencia de los halcones borní. Debería mantenerse una población estable de halcones borní en Sicilia tanto a pequeña como a gran escala.
Massimiliano Di Vittorio; Andrea Ciaccio; Salvatore Grenci; Luca Luiselli. Ecological Modelling of the Distribution of the Lanner FalconFalco biarmicus feldeggiiin Sicily at Two Spatial Scales. Ardeola 2015, 62, 81 -94.
AMA StyleMassimiliano Di Vittorio, Andrea Ciaccio, Salvatore Grenci, Luca Luiselli. Ecological Modelling of the Distribution of the Lanner FalconFalco biarmicus feldeggiiin Sicily at Two Spatial Scales. Ardeola. 2015; 62 (1):81-94.
Chicago/Turabian StyleMassimiliano Di Vittorio; Andrea Ciaccio; Salvatore Grenci; Luca Luiselli. 2015. "Ecological Modelling of the Distribution of the Lanner FalconFalco biarmicus feldeggiiin Sicily at Two Spatial Scales." Ardeola 62, no. 1: 81-94.