Search results for "HABITAT"
showing 10 items of 1243 documents
Helminth communities of loggerhead turtles (Caretta caretta) from Central and Western Mediterranean Sea: the importance of host's ontogeny.
2009
We investigated the factors providing structure to the helminth communities of 182 loggerhead sea turtles, Caretta caretta, collected in 6 localities from Central and Western Mediterranean. Fifteen helminth taxa (10 digeneans, 4 nematodes and 1 acanthocephalan) were identified, of which 12 were specialist to marine turtles; very low numbers of immature individuals of 3 species typical from fish or cetaceans were also found. These observations confirm the hypothesis that phylogenetic factors restrict community composition to helminth species specific to marine turtles. There were significant community dissimilarities between turtles from different localities, the overall pattern being compat…
From glacial refugia to hydrological microrefugia: Factors and processes driving the persistence of the climate relict tree Zelkova sicula
2021
Abstract With only two tiny populations, the climate relict Zelkova sicula (Sicily, Italy) is one of the rarest trees in the world. It also represents the most marginal member of genus Zelkova that was widespread in the broadleaved forests thriving in warm–temperate climates throughout Eurasia until the Last Glacial Age. Occurring at the westernmost range of the genus under typical Mediterranean climate, the micro‐topographic settings have always appeared crucial for the survival of this relict. However, the factors and processes actually involved in its persistence in the current refugia, as well as the response of similar relict trees in arid environments, are poorly understood worldwide.…
Sporadic nesting reveals long distance colonisation in the philopatric loggerhead sea turtle (Caretta caretta)
2018
The colonisation of new suitable habitats is crucial for species survival at evolutionary scale under changing environmental conditions. However, colonisation potential may be limited by philopatry that facilitates exploiting successful habitats across generations. We examine the mechanisms of long distance dispersal of the philopatric loggerhead sea turtle (Caretta caretta) by analysing 40 sporadic nesting events in the western Mediterranean. The analysis of a fragment of the mitochondrial DNA and 7 microsatellites of 121 samples from 18 of these nesting events revealed that these nests were colonising events associated with juveniles from distant populations feeding in nearby foraging gro…
Threatened biogenic formations of the Mediterranean: Current status and assessment of the vermetid reefs along the Lebanese coastline (Levant basin)
2019
Abstract Vermetid reefs are a key intertidal habitat in the warm-temperate part of the Mediterranean Sea and in some subtropical and tropical regions in the Atlantic and Pacific oceans. This unique and highly diverse ecosystems is under siege due to both the high anthropogenic pressure and the global climate change, with documented local population declines in the Eastern Mediterranean. This study aims at evaluating the conservation state of vermetid reefs along the Lebanese coast (Eastern Mediterranean), where seawater warming, habitat degradation and coastal urbanization likely threaten their presence. In order to assess the conservation status of vermetid reefs in Lebanon, five sites wer…
Biodiversity in canopy-forming algae: Structure and spatial variability of the Mediterranean Cystoseira assemblages
2018
Abstract In the Mediterranean Sea, Cystoseira species are the most important canopy-forming algae in shallow rocky bottoms, hosting high biodiverse sessile and mobile communities. A large-scale study has been carried out to investigate the structure of the Cystoseira-dominated assemblages at different spatial scales and to test the hypotheses that alpha and beta diversity of the assemblages, the abundance and the structure of epiphytic macroalgae, epilithic macroalgae, sessile macroinvertebrates and mobile macroinvertebrates associated to Cystoseira beds changed among scales. A hierarchical sampling design in a total of five sites across the Mediterranean Sea (Croatia, Montenegro, Sardinia,…
Parhyale plumicornis (Crustacea: Amphipoda: Hyalidae): is this an anti-lessepsian Mediterranean species? Morphological remarks, molecular markers and…
2016
Hyalid amphipods living in coastal marine habitats are frequently included in ecological studies. The systematics of this taxon has been subject to profound changes, with an emphasis on the North Pacific fauna. Since a proper species delimitation is a prerequisite in taxonomic and ecological studies, Parhyale plumicornis (Heller, 1866) has been herein re-described, showing the criticisms and mismatches of various characters, which were previously used in dichotomous keys. This species was collected for the first time off the western coast of Sicily Island (Italy: central Mediterranean Sea). The male is peculiar, due to the second antennae heavily setose posteriorly and bearing long tufts of…
Plant invasions on small Mediterranean islands. An overview
2016
Biological invasions have become one of the main drivers of habitat degradation and a leading cause of biodiversity loss in island ecosystems worldwide. The spread of invasive species poses a particular environmental threat on the islands of the Mediterranean Basin, which are hot spots of biodiversity and contain rare habitats and endemic species, especially on small islands, which are highly vulnerable to biodiversity loss. Following a recent survey, in this paper we aim to provide an overview of the present-day non-native vascular flora of small Mediterranean islands based on a sample of 37 islands located in the middle of the Mediterranean Sea, off the coast of Italy. By comparing the cu…
Environmental factors determining the establishment of the African Long-legged BuzzardButeo rufinus cirtensisin Western Europe
2017
Winters have become warmer under the impact of climate change, which has modified the phenology of birds and also their distribution ranges. The African Long-legged Buzzard Buteo rufinus cirtensis has recently colonized Europe via the Strait of Gibraltar. We aim to explain the native distribution of this species and to predict favourable areas in newly colonized parts of Europe using geospatial modelling to identify the most influential factors in this process. We applied the favourability function, a generalized linear model describing environmental favourability, for the presence/absence of breeding areas in northern Morocco and the southern Iberian Peninsula, according to a set of variab…
Mediterranean rocky reefs in the Anthropocene: Present status and future concerns
2021
Abstract Global change is striking harder and faster in the Mediterranean Sea than elsewhere, where high levels of human pressure and proneness to climate change interact in modifying the structure and disrupting regulative mechanisms of marine ecosystems. Rocky reefs are particularly exposed to such environmental changes with ongoing trends of degradation being impressive. Due to the variety of habitat types and associated marine biodiversity, rocky reefs are critical for the functioning of marine ecosystems, and their decline could profoundly affect the provision of essential goods and services which human populations in coastal areas rely upon. Here, we provide an up-to-date overview of …
Phytosociological survey vegetation map of Sicily (Mediterranean region)
2016
ABSTRACTWe present the results of a study aimed at developing a vegetation map of Sicily (Italy) including the smaller circum-Sicilian islands, for an area of approximately 25,703 km2. The work is a synthesis of studies carried out in accordance with the survey methodology of phytosociology in the last 40 years over the whole study area. The vegetation map of Sicily was compiled in a Geographical Information Systems (GIS) environment, in order to produce a cartographic representation at a scale of 1:10,000 (reduced to a scale of 1:250,000). The physiognomic-structural characteristics of the plant landscape of Sicily are analyzed, providing a general and, at the same time, detailed overview …