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Bastia, France

Tlili W.,Tunis el Manar University | Nefla A.,Tunis el Manar University | Delaugerre M.,Conservatoire du littoral | Ouni R.,Wildlife Conservation Society | Nouira S.,Tunis el Manar University
Acta Herpetologica | Year: 2014

Tunisian geckos count nine species (1 is insular relict, 1 is endemic, 2 are ubiquitous and 5 are enfeoffed). We aim to determine factors influencing their distributions. Surveys were founded on environmental divisions. Presence/ absence data for 113 grids were analyzed using multivariate tools. 18 environmental variables were revealed and clustered into five factors to model species distributions. Established models were further projected on non-explored areas within Tunisian territory. The distribution of continental geckos follows an indirect bidirectional gradient; the South-northward one is physiologically stressful and the North-southward one is biologically stressful. Five biogeographic regions were established showing concordance with climatic and vegetation regionalization. The distribution of non-anthropophilic species is positively correlated to thermal amplitudes gradient. The distribution of anthropophilic taxa is positively correlated to agricultural land-use. Oasis, sebkhas and chotts are particular landscapes that disturb both distributions. Predicted areas follow the yielded distribution patterns despite some discrepancy for S. sthenodactylus. The niche characterizing shows that land use and altitude increase the probability of occurrence of H. turcicus and T. mauritanica. Alternatively, they decrease the probability of the presence of T. deserti, T. neglecta, T. tripolitanus and S. petrii. Models could also show that the absence of S. sthenodactylus in northern regions is attributed to high altitudes and cereal land-use. As to T. fascicularis, the displacement of the northern limits of its range is mostly attributed to an improvement of field investigations. Established model of its distribution shows a restricted area of probable occurrence in central Tunisia confirming its endemism. © Firenze University Press. Source

Michel-Jean D.,Conservatoire du littoral
Acta Herpetologica | Year: 2013

Hierophis viridiflavus has a strong diurnal rhythm as demonstrated by many field studies. It belongs to the "Whip snakes" characterized by slender bodies, large eyes, high speed, saurophagy and diurnality. On Giraglia island (Corsica) the snakes do forage also nightly. This unexpected shift in the circadian rhythm might be related to a local adaptation to trophic requirements. © Firenze University Press. Source

The Havre de Regnéville, France, is a major wintering site for the East Canadian High Arctic Light-bellied Brent Goose Branta bernicla hrota (LBBG) population, which winters mainly on well-known and well-studied sites along the Irish coast. This wintering site has very little eelgrass Zostera sp. available and the geese regularly feed on saltmarshes grazed by sheep. The Conservatoire du littoral is developing several studies to provide a better understanding of why LBBG use this site and to evaluate the possible effects of climate change on its habitat. In particular, the proposed study will analyse a potential conflict of interests between biodiversity and agricultural activity in the area, to provide tools for a better coexistence between the geese and sheep feeding on the saltmarshes. © Wildfowl and Wetlands Trust. Source

Gremillet D.,French National Center for Scientific Research | Gremillet D.,University of Cape Town | Peron C.,French National Center for Scientific Research | Peron C.,Australian Antarctic Division | And 5 more authors.
Marine Biology | Year: 2014

Recent meta-analyses identified conservation hotpots at the scale of the Mediterranean, yet those may be crude by lack of detailed information about the spatial ecology of the species involved. Here, we identify an irreplaceable marine area for >95 % of the world population of the Scopoli’s shearwater (Calonectris diomedea), which is endemic to the Mediterranean and breeds on the island of Zembra off Tunis. To this end, we studied the three-dimensional at-sea movements of 50 breeding adults (over a total of 94 foraging trips) in 2012 and 2013, using GPS and temperature–depth recorders. Feathers were also collected on all birds to investigate their trophic status. Despite Zembra being the largest seabird colony in the Mediterranean (141,000 pairs), the per capita home-range of Scopoli’s shearwaters foraging from this colony was not larger than that of birds from much smaller colonies, indicating highly beneficial feeding grounds in the Gulf of Tunis and off Cap Bon. Considering depleted Mediterranean small pelagic fish stocks, supposed to be Scopoli’s shearwater prey base, we therefore speculate that birds may now also largely feed on zooplankton, something which is supported by our stable isotopic analyses. Crucially, shearwater at-sea feeding and resting areas showed very little overlap with a conservation hotspot recently defined on the western side of the Gulf of Tunis using meta-analyses of species distributions relative to anthropogenic threats. We therefore propose a major extension to this conservation hotspot. Our study stresses the importance of detailed biotelemetry studies of marine megafauna movement ecology for refining large-scale conservation schemes such as marine protected area networks. © 2014, Springer-Verlag Berlin Heidelberg. Source

Ouni R.,Association de Sauvegarde du Patrimoine Environnemental et Naturel | Serra J.M.,Species Protection Service | Essetti I.,Wildlife Conservation Society | Thevenet M.,Conservatoire du littoral | Renou S.,Conservatoire du littoral
Alauda | Year: 2012

Possible breeding of European Storm Petrel Hydrobates pelagicus at Zembra Island, Tunisia. After investigations over five years, the first record of 6 individuals in late June 2012 suggests the possibility that this species breeds on Zembra and Zembretta archipelago in Tunisia. Source

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