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Akani G.C.,Rivers State University of Science And Technology | Ebere N.,Rivers State University of Science And Technology | Franco D.,Planland | Eniang E.A.,University of Uyo | And 3 more authors.
Journal of Venomous Animals and Toxins Including Tropical Diseases | Year: 2013

Background: Venomous snakes are among the most serious health hazards for rural people in tropical regions of the world. Herein we compare the monthly activity patterns of eight venomous snake species (Elapidae and Viperidae) with those of rural people in the Niger Delta area of southern Nigeria, in order to identify the periods of highest potential risk for persons, and the human group actually at greater risk of snakebite.Results: We documented that above-ground activity of all venomous snakes peaked in the wet season, and that high snake activity and high human activity were most highly correlated between April and August. In addition, we documented that women and teenagers were at relatively higher risk of encountering a venomous snake than adult males, despite they are less often in the field than men.Conclusions: Our results suggest that future programs devoted to mitigate the social and health effects of snakebites in the Niger Delta region should involve especially women and teenagers, with ad-hoc education projects if appropriate. We urge that international organizations working on social and health problems in the developing world, such as IRD, DFID, UNDP, should provide advice through specific programs targeted at especially these categories which have been highlighted in comparatively potential higher threat from snakebites than adult men. © 2013 Akani et al.; licensee BioMed Central Ltd.


Auliya M.,Helmholtz Center for Environmental Research | Altherr S.,Pro Wildlife | Ariano-Sanchez D.,University of the Valley of Guatemala | Baard E.H.,Western Cape Nature Conservation Board | And 35 more authors.
Biological Conservation | Year: 2016

Of the 10,272 currently recognized reptile species, the trade of fewer than 8% are regulated by the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) and the European Wildlife Trade Regulations (EWTR). However, the International Union for Conservation of Nature (IUCN) Red List has assessed 45% of the world's reptile species and determined that at least 1390 species are threatened by "biological resource use". Of these, 355 species are intentionally targeted by collectors, including 194 non-CITES-listed species. Herein we review the global reptile pet trade, its impacts, and its contribution to the over-harvesting of species and populations, in light of current international law. Findings are based on an examination of relevant professional observations, online sources, and literature (e.g., applicable policies, taxonomy [reptile database], trade statistics [EUROSTAT], and conservation status [IUCN Red List]). Case studies are presented from the following countries and regions: Australia, Central America, China, Galapagos Islands (Ecuador), Germany, Europe, India, Indonesia (Kalimantan), Islamic Republic of Iran, Japan, Madagascar, Mexico, New Zealand, the Philippines, South Africa, Sri Lanka, Vietnam, Western Africa, and Western Asia. The European Union (EU) plays a major role in reptile trade. Between 2004 and 2014 (the period under study), the EU member states officially reported the import of 20,788,747 live reptiles. This review suggests that illegal trade activities involve species regulated under CITES, as well as species that are not CITES-regulated but nationally protected in their country of origin and often openly offered for sale in the EU. Further, these case studies demonstrate that regulations and enforcement in several countries are inadequate to prevent the overexploitation of species and to halt illegal trade activities. © 2016 Elsevier Ltd.


Luiselli L.,Rivers State University of Science And Technology | Luiselli L.,Environmental Studies Center Demetra | Amori G.,National Research Council Italy | Akani G.C.,Rivers State University of Science And Technology | And 2 more authors.
Biodiversity and Conservation | Year: 2015

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. © 2015, Springer Science+Business Media Dordrecht.


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.


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.


Luiselli L.,Rivers State University of Science And Technology | Luiselli L.,Environmental Studies Center Demetra | Petrozzi F.,Rivers State University of Science And Technology | Petrozzi F.,Environmental Studies Center Demetra | And 3 more authors.
Ecological Research | Year: 2015

Islands provide an evolutionary window, where a simplified natural network combined with unusual environmental conditions promote selective processes that trigger rapid changes in biological constituents of a species. The Mediterranean island of Montecristo, Italy, provides such a situation with a reduced fauna and flora compared to the mainland. We measured body size (SVL) and recorded diet of the two snake species occurring on the island, the Asp Viper (Vipera aspis) and the Western Whip Snake (Hierophis viridiflavus), and compared these data with populations of conspecifics from the mainland. Compared to mainland populations, the three principal results are: (1) no obvious niche shift along the food or habitat axes between the two snake species; (2) significant body size shift (insular dwarfism) of the whip snake by 30 %, and ca. 10 % in the viper; and (3) arboreal ambushing in the viper to add an alternative diet (birds) compared to mainland populations (more mice) to compensate for the lack of suitable micro-mammals on Montecristo Island. © 2015, The Ecological Society of Japan.

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