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Hoinsoude Segniagbeto G.,University of Lomé | Eniang E.A.,University of Uyo | Petrozzi F.,Rivers State University of Science And Technology | Petrozzi F.,Ecologia Applicata Italia S.r.l. | And 4 more authors.
Tropical Zoology | Year: 2015

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. © 2015 Istituto per lo Studio degli Ecosistemi of the Consiglio Nazionale delle Ricerche, Firenze.


Vignoli L.,Third University of Rome | Segniagbeto G.H.,University of Lomé | Eniang E.A.,University of Uyo | Hema E.,University of Ouagadougou | And 4 more authors.
Journal of Natural History | Year: 2016

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 boa Eryx 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. © 2015 Taylor & Francis.


Petrozzi F.,Rivers State University of Science And Technology | Petrozzi F.,Ecologia Applicata Italia s.r.l. | Akani G.C.,Rivers State University of Science And Technology | Amadi N.,Rivers State University of Science And Technology | And 4 more authors.
Tropical Zoology | Year: 2015

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 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. © 2015 Istituto per lo Studio degli Ecosistemi of the Consiglio Nazionale delle Ricerche, Firenze


Akani G.C.,Rivers State University of Science And Technology | Petrozzi F.,Rivers State University of Science And Technology | Petrozzi F.,Ecologia Applicata Italia S.r.l | Luiseixi L.,Rivers State University of Science And Technology | Luiseixi L.,Environmental Studies Center Demetra
Revue d'Ecologie (La Terre et la Vie) | Year: 2014

Despite many studies of reptile community composition in Africa, no studies document the variation of reptile assemblages across different plantation types. Here, we document the community composition (richness, taxonomic composition, dominance, evenness) in relation to seasonality in eight different plantation types (from cassava-yam to banana-plantain, and from cacao to mixed orchards), and at three distinct study areas in the River Niger Delta of southern Nigeria. Our study showed that the community composition of reptiles did not differ significantly across plantation types in terms of species diversity and richness during the wet season, but it did so during the dry season (possibly as a consequence of survey effects). A few highly dominant lizard species (Agama agama and Trachylepis affinis) constituted the great majority of the specimens encountered during field work. Some snake species, although usually not very abundant (in terms of relative number) were observed in nearly all sites. Typical forest specialists may enter plantations, but they were never abundant there. Tortoises did not occur in any plantations. Diversity indices and multivariate sets of analyses revealed minor differences among study areas and across plantation types in terms of community composition patterns. However, some types of monoculture plantations had higher dominance and lower evenness values than mixed orchards (= poly-culture farms), showing that monocultures provided least quality habitats for reptile communities than poly-culture farms, favoring few species due to the relatively homogeneous niche availability. Overall, a clear process of biotic homogenization, with increases in dominance, was clearly observed at all sites.


Petrozzi F.,Rivers State University of Science And Technology | Petrozzi F.,Ecologia Applicata Italia S.r.l. | Akani G.C.,Rivers State University of Science And Technology | Luiselli L.,Rivers State University of Science And Technology | And 3 more authors.
Amphibia Reptilia | Year: 2014

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. © Copyright 2014 by Koninklijke Brill NV, Leiden, The Netherlands.


Akani G.C.,Rivers State University of Science And Technology | Eniang E.A.,University of Uyo | Petrozzi F.,Rivers State University of Science And Technology | Petrozzi F.,Ecologia Applicata Italia S.r.l. | And 3 more authors.
Amphibia Reptilia | Year: 2014

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; Leptotyphlops cfr. sundewalli). © Copyright 2014 by Koninklijke Brill NV, Leiden, The Netherlands.


Akani G.C.,Rivers State University of Science And Technology | Aifesehi P.E.E.,University of Port Harcourt | Petrozzi F.,Rivers State University of Science And Technology | Petrozzi F.,Ecologia Applicata Italia S.r.l. | And 3 more authors.
Tropical Zoology | Year: 2014

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. © 2014 Istituto per lo Studio degli Ecosistemi of the Consiglio Nazionale delle Ricerche, Firenze.


Akani G.C.,Rivers State University of Science And Technology | Aifesehi P.E.E.,University of Port Harcourt | Petrozzi F.,Rivers State University of Science And Technology | Petrozzi F.,Ecologia Applicata Italia s.r.l. | And 3 more authors.
Vie et Milieu | Year: 2014

The Taylor Creek Forest reserve (Bayelsa State) is one of the most important protected areas of the River Niger Delta region, southern Nigeria. Unfortunately, however, no field studies are available on the diversity of the terrestrial vertebrates (amphibians, reptiles, mammals) in this protected territory. Here, we report the results of field surveys devoted to assess on a preliminary base the vertebrate diversity of Taylor Creek Forest reserve. Mammals and amphibians were assessed only qualitatively, whereas reptiles were assessed also quantitatively within 15 plots of 2 ha area. We detected about 70 vertebrate species (some genera may include multiple species that remained non-detected in our surveys). Several of the recorded species were of high conservation concern (e.g. manatee, dwarf crocodile, hinge-back tortoises, etc.). The presence of the endangered Nigerian chimpanzee was suspected for the Forest Reserve, and indeed few groups of this species do occur in the surroundings of the protected area. Analysis of the reptile diversity suggested that, however, species dominance was high and evenness was low, with very few lizard species dominating the samples. Thus, the reptile community diversity profile revealed altered ecological conditions in this forest area. The conservation implications of the observed patterns are also discussed.


Di Vittorio M.,Ecologia Applicata Italia srl | Ciaccio A.,Coordinamento Tutela Rapaci Sicilia | Grenci S.,Coordinamento Tutela Rapaci Sicilia | Luiselli L.,Environmental Studies Center Demetra | Luiselli L.,Rivers State University of Science And Technology
Ardeola | Year: 2015

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.


Rugiero L.,Demetra s.r.l. | Milana G.,University of Rome La Sapienza | Petrozzi F.,Ecologia Applicata Italia s.r.l. | Capula M.,Museo Civico di Zoologia | Luiselli L.,Demetra s.r.l.
Acta Oecologica | Year: 2013

Global warming is thought to be a far-reaching threat to biodiversity, and is supposed to influence several aspects of the ecology of animals. Global warming should influence especially the ectotherm vertebrates, which depend directly from the external thermal conditions for their activities and performances. Here, we analyze the changes in phenology which have occurred in the last 20 years in a marked population of vipers, Vipera aspis, and we try to relate these changes with the intervening climatic changes. We analyzed three metrics of viper's annual phenology: (i) annual onset of above-ground activity (hereby AOA); (ii) annual onset of feeding period (AOF); (iii) annual onset of the hibernation (AOH). The annual variations of these three phenological metrics were correlated to five variables of climatic data: (1) mean annual air temperature, (2) mean February air temperature, (3) mean July air temperature, (4) yearly number of rainy days, and (5) yearly number of days with rainstorm. We observed a statistically significant reduction of AOA values from >28 days between 1987 and 1997, to approximately 20 days from 1998 to 2011, with a similar statistical trend also found for AOF values. The number of days of delay in entering hibernation increased significantly since 1998. Three sets of relationships between climatic variables and metrics of viper phenology were statistically significant, i.e. the correlation (i) between annual mean temperature and AOA (negative), (ii) between annual mean temperature and AOF (negative), and (iii) between annual mean temperature and AOH (positive). The percent of field days (between 20th February and 20th March) with no viper observed also decreased significantly over the years. Our study showed that three different traits of the annual phenology of a Mediterranean snake are shifting in the 20+ years of monitoring, and that there is correlational evidence that these shifts are linked to intervening climate change. © 2013 Elsevier Masson SAS.

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