Search results for "Fauna"
showing 10 items of 513 documents
Impact of genetic diversity of an earthworm on decomposition and ecosystem functioning
2020
Abstract Ecosystem functioning is affected positively by increased biodiversity, through complementary functions of multiple species or because high-functioning species are more likely in a species-rich community. Genetic diversity is one level of biodiversity that has been shown to positively affect ecosystem functioning. Whether the genetic diversity of a key decomposer species affects decomposition processes, and ecosystem functioning in general, is still unknown. We compared low and high genetic diversity assemblages of the earthworm Dendrobaena octaedra in two different experiments: using microcosms containing a simple community of other decomposer animals (some nematodes and other mic…
The response of cultured meiofaunal and benthic foraminiferal communities to lead exposure: Results from mesocosm experiments
2018
Lead (Pb) has been regarded as a very toxic element that poses a serious threat to biota. A mesocosm experiment is performed to assess the influence of Pb on meiofaunal (metazoans within 45-500 µm) and benthic foraminiferal (protozoans) communities. To this end, sediments bearing such communities are incubated in mesocosms, exposed to different levels of Pb in seawater, and monitored for up to eight weeks. Concentrations of Pb below 1 ppm in water do not promote a significant increase of this metal in sediments. Relatively high concentrations of Pb seem to affect meiofaunal and benthic foraminiferal communities by reducing their richness or diversity, and the abundance of the most sensitive…
A Visitor of Tropical Waters: First Record of a Clymene Dolphin (Stenella clymene) Off the Patagonian Coast of Argentina, With Comments on Diet and M…
2021
The poorly known Clymene dolphin (Stenella clymene) is a small oceanic cetacean distributed in tropical and subtropical waters of the Atlantic Ocean. In this study, we report, for the first time, a vagrant individual of Clymene dolphin in Argentina (Rada Tilly) that represents the current southern-most record for this cetacean species. We provide a molecular identification of the dolphin, based on partial sequences of the mitochondrial cytochrome b gene, generated from DNA extracted from its metazoan parasites. Three prey species, namely Argentine hake, Patagonian squid and lobster krill were identified from hard pieces collected in the stomach. Seven metazoan parasite taxa (three in adult …
Parasitic outbreak of the copepod Balaenophilus manatorum in neonate loggerhead sea turtles (Caretta caretta) from a head-starting program
2017
Abstract Background Diseases associated to external parasitosis are scarcely reported in sea turtles. During the last decades several organism have been documented as a part of normal epibiont community connected to sea turtles. The copepod Balaenophilus manatorum has been cited as a part of epibiont fauna with some concern about its parasitic capacity. This study serves three purposes, i.e. (i) it sheds light on the type of life style that B. manatorum has developed with its hosts, particularly turtles; (ii) it makes a cautionary note of the potential health risks associated with B. manatorum in sea turtles under captivity conditions and in the wild, and (iii) it provides data on effective…
Helminth fauna of the invasive American red-eared sliderTrachemys scriptain eastern Spain: potential implications for the conservation of native terr…
2015
AbstractIn this study we report on the helminth fauna of the invasive American red-eared slider Trachemys scripta in five localities from eastern Spain where this species co-occurs with two native, endangered freshwater turtles, i.e. Emys orbicularis and Mauremys leprosa. In total, 46 individuals of T. scripta were analysed for parasites. Adult individuals of three helminth species were found: the monogenean Neopolystoma orbiculare, the digenean Telorchis solivagus and the nematode Serpinema microcephalus. Telorchis solivagus and S. microcephalus are trophically transmitted parasites of native turtles that probably infected T. scripta through shared infected prey. Neopolystoma orbiculare in…
Structuring factors of the spatio-temporal variability of macrozoobenthos assemblages in a southern Mediterranean lagoon: How useful for bioindicatio…
2017
International audience; The authors investigated the impact of the extension of the El Kantra Channel on the composition and structure of macrobenthic assemblages in Boughrara Lagoon (Gulf of Gabes, Tunisia along with the use of 4 biotic indices (AMBI, BENTIX, M-AMBI and TUBI). Thirteen stations were sampled seasonally in 2012–2013. Forty-one species were found in 2012–2013 not recorded in 2009–2010, including 20 species of polychaetes belonging to the trophic groups of deposit-feeders and carnivores which are expected to increase in areas disturbed by organic pollution. During the survey, we recorded a high fish mortality, essentially caused by the development of harmful algal blooms (HAB)…
Forest snail faunas from Transylvania (Romania) and their relationship to the faunas of Central and Northern Europe
2011
Forty-three forest sites in seven sampling areas in mountainous parts of Transylvania were sampled to obtain inventories of their snail faunas, and to make comparisons between these and the faunas of similar sites further north along the Carpathian chain. Sampling areas ran from close to the Ukrainian border in the north to Retezat in the south-west. Altogether, 83 species were found, as well as between 19 and 40 species at individual sites. Sites within the same sampling area had more species in common than in among-area comparisons, although differences between areas did not relate to the distance between them. Such differences appear to be related more to ecological factors than to geogr…
An integrative approach challenges species hypotheses and provides hints for evolutionary history of two Mediterranean freshwater palaemonid shrimps …
2021
25 pages; International audience; The Mediterranean Region is a biodiversity/endemism hotspot whose freshwater fauna remains largely unexplored. Our integrative study challenges the taxonomic status of two freshwater palaemonid shrimps, Palaemon antennarius and Palaemon minos. Three molecular operational taxonomic units (MOTUs) were defined based on 352 cytochrome oxidase subunit I (COI) sequences and 88 haplotypes. Two belonged to P. antennarius: one inhabiting the Apennine Peninsula and Sicily, and the other from the Balkan Peninsula. Palaemon minos was the third MOTU, found on Crete. The Balkan MOTU of P. antennarius was genetically closer to P. minos than to the other conspecific MOTU. …
Floristic and Vegetation Changes on a Small Mediterranean Island over the Last Century
2021
A synthetic and updated overview about the vascular flora and vegetation of the Island of Capo Passero (SE-Sicily) is provided. These data issue from two series of field surveys—the first carried out between 1997 and 2000, and the second between 2005 and 2019 and mostly focused on refining and implementing vegetation data. The current islet’s flora consists of 269 taxa, of which 149 (58%) are annual plants. The Mediterranean species are largely prevailing, 108 (40%) of which have a strictly Mediterranean biogeographical status. The comparison with a species list published in 1919 and updated in 1957 suggest that, despite the overall prevalence of anemochorous taxa, the vertebrate fauna repr…
Assessment of surface sediment dynamics and response of benthic macrofauna assemblages in Boughrara Lagoon (SW Mediterranean Sea)
2016
International audience; A study was conducted in the spring of 2009, the winters of 2010 and 2013, and in the summer of 2012 at 13 stations in Boughrara Lagoon, Tunisia (southern Mediterranean). The country’s largest lagoon, it is considered to be an anthropogenically stressed area, though a major tourist centre—Djerba Island—is located along its northern shores. The lagoon bottoms were studied via analyses of grain size, surface sediment composition, total organic matter (TOM) and through the trophic and functional organisation of benthic macrofauna. The results indicate that the bottoms are composed of fine, medium or coarse sands and that sediment distribution is controlled by water move…