Impact of anthropogenic disturbances on beetle communities of French Mediterranean coastal dunes

In coastal dunes, influenced by anthropogenic activities such as tourism, it is important to determine the relative influence of environmental factors at different spatial scales to evaluate the sensitivity of local communities to disturbances. We analyzed beetle communities of 14 dunes of the French Mediterranean coast: four in the relatively preserved Camargue area, and ten in the Var department, where tourism is intensive. Beetle communities were studied three times in early spring using sand sampling. Species-environment relationships were evaluated at the regional, landscape and local scale using redundancy analysis (RDA) and variability partitioning. About 28 species were identified, of which 15 were sand-specialist species, which accounted for more than 93% of total abundance. The beetle communities of Camargue were significantly different from those of the Var department owing to the pullulation of a Tenebrionid species (Trachyscelis aphodioides Latr.) in the Var, except for one restored dune where the community was very similar to those of Camargue. Our results showed no longitudinal gradient between the two regions. Local factors (dune height, preservation and disturbance index) significantly explained most of the variation in the dominance of T. aphodioides, while some other local factors were important for other psammophilous species. This study also suggests that dune beetle communities are strongly affected on beaches intensively managed for tourism, but beetles are still abundant in much disturbed sites

First record of <I>Telmatogeton </I>sp. (Diptera: Chironomidae) at Heard Island

NatuurwetenskappeSoologiePlease help us populate SUNScholar with the post print version of this article. It can be e-mailed to: [email protected]

First record of Telmatogeton sp. (Diptera: Chironomidae) at Heard Island

Several specimens (larvae, pupa, females) of Telmatogeton sp. were found for the first time at Heard Island in the 2000/2001 season. Owing to the morphological characters of the individuals collected, the absence of males among the material, and lack of information concerning morphological variation in most Telmatogeton species from the Southern Ocean islands, it was not possible to assign the individuals to any of the species known from this biogeographical province with any confidence. Further sampling at Heard Island and re-examination of material from all of the other species are required to resolve the identity of the Telmatogeton species at Heard Island.Articl

Responses of common buzzard (Buteo buteo) and Eurasian kestrel (Falco tinnunculus) to land use changes in agricultural landscapes of Western France

In front of land use changes, there has been a wide decline in biodiversity. In this study, we analysed the numerical response of two diurnal raptor species, the common buzzard and the Eurasian kestrel to different agricultural landscape contexts. We carried out a 3-year survey of the abundance of these two species in three agricultural landscape contexts that are known to form a gradient of land use intensity and hedgerow network fragmentation. We also considered the variation in prey abundance related to these land use changes. The two raptor species showed negative but differentiated response patterns to land use intensification and small mammal abundance. The abundance of the common buzzard decreased significantly with the reduction of hedgerows, woodlots and grasslands areas, as well as with the decrease in prey abundance at the landscape scale. The abundance of the Eurasian kestrel showed the same trend, but fall of abundance was less marked and not significant. This resulted in a reverse ratio of species density according to agricultural intensification and landscape openness. Specific feeding habits, nesting habitats and spatial partitioning in foraging areas could explain the difference in the numerical response observed for these two raptor species. Buzzards forage mainly on highly profitable prey areas and avoid highly fragmented woodland habitats for nesting. Kestrels seem less dependent on semi-natural habitats, are able to nest in more fragmented landscapes and are better adapted to exploit less abundant but more widespread small mammal prey species within the cultivated matrix. The study may help to evaluate carrying capacities of agricultural landscapes in accordance with ecological life traits of these two raptor specie