Search results for "Biological Invasion"
showing 10 items of 59 documents
A co-invasive microsporidian parasite that reduces the predatory behaviour of its host Dikerogammarus villosus (Crustacea, Amphipoda).
2014
SUMMARYParasites are known to affect the predatory behaviour or diet of their hosts. In relation to biological invasions, parasites may significantly influence the invasiveness of the host population and/or mediate the relationships between the invader and the invaded community. Dikerogammarus villosus, a recently introduced species, has had a major impact in European rivers. Notably, its high position in trophic web and high predatory behaviour, have both facilitated its invasive success, and affected other macroinvertebrate taxa in colonized habitats. The intracellular parasite Cucumispora dikerogammari, specific to D. villosus, has successfully dispersed together with this amphipod. Data…
First record of Aplysia dactylomela (Opisthobranchia: Aplysiidae) from the Egadi Islands (western Sicily)
2014
The alien mollusc Aplysia dactylomela is recorded for the first time from the Egadi Islands marine protected area (western Sicily). This species has been widely reported in the Mediterranean and has established populations in Sicily. The presence of a few specimens let us suppose that its occurrence in this area is a recent event and that soon new populations will be sighted in the whole Egadi Islands and on the western and southern coasts of Sicily.
Cryptic invasion in Southern Europe: The case of Ferrissia fragilis (Pulmonata: Ancylidae) Mediterranean populations
2011
Four populations of the North American ancylid gastropod Ferrissia fragilis have been found in Southern Italy, thus expanding the known Eurasian distribution range of this invasive gastropod to the Mediterranean area. Both mitochondrial markers used for the molecular identification of the sampled specimens (16S and COI) showed a modest to absent haplotypic diversity in the studied Ferrissia populations from Europe and Asia, and their perfect identity with some of the haplotypes observed in North American F. fragilis populations. In the light of the scarce molecular diversity observed in the whole Palaearctic area and of the growing evidences for the ongoing spreading of the species in Europ…
Stable isotope analysis reveals trophic segregation between the invasive zebra mussel Dreissena polymorpha and the native duck mussel Anodonta anatin…
2022
AbstractNon-indigenous freshwater bivalves negatively affect invaded ecosystems through different mechanisms, including inter-specific competition for trophic resources. Here, we investigated in Lake Trasimeno (Central Italy) the diet of the invasive Dreissena polymorpha and the native Anodonta anatina. δ15N and δ13C stable isotopes were measured in winter and summer in bivalves, phytoplankton, and sedimentary organic matter (SOM); the relative dietary contributions of the two resources were determined using Bayesian mixing models. To elucidate the different carbon and nitrogen pools characterizing the study site, isotopic analyses were extended to zooplankton and to representatives of the …
The genus Tamarix (Tamaricaceae) from archaeological to contemporary landscape
2018
This review includes the data concerning the presence of Tamarix species in old and contemporary landscapes, and their presence in archaeological areas. Their role as wild and ornamental plants, their use in sacred places, and their depiction in old relief sculpture, old and more recent paintings is also reported. Notes on the presence of Tamarix species in current landscapes and their invasiveness are discussed.
Different invasibility of permanent and temporary waterbodies in a semiarid Mediterranean Island
2019
Nonindigenous species (NIS) represent a threat to aquatic biodiversity worldwide. However, freshwater ecosystems in drylands are potentially more prone to biological invasions than those located in temperate regions because of the higher number of artificial waterbodies generally occurring in these areas, which might act as invasion hubs for NIS. We review the available information about NIS in Sicilian waterbodies, discuss the role exerted by artificial lakes and ponds in facilitating the establishment of NIS in arid and semiarid areas, and compare the invasibility of permanent and temporary waterbodies in drylands. Artificial waterbodies increase the target-area effect for dispersers and …
Food selection of a generalist herbivore exposed to native and alien seaweeds
2018
Understanding which factors influence the invasion of alien seaweed has become a central concern in ecology. Increasing evidence suggests that the feeding preferences of native herbivores influence the success of alien seaweeds in the new community. We investigated food selection of a generalist native grazer Paracentrotus lividus, in the presence of two alien seaweeds (Caulerpa cylindracea and Caulerpa taxifolia var. distichophylla) and two native seaweeds (Dictyopteris membranacea and Cystoseira compressa). Sea urchins were fed with six experimental food items: C. cylindracea, C. taxifolia var. distichophylla, a mixture of C. cylindracea and C. taxifolia var. distichophylla, D. membranace…
Feeding preferences of Paracentrotus lividus exposed to native and non-native macroalgae
2016
The effects of alien macroalgal invasions on ecosystem functioning may depend on the feeding choice of native herbivores between native and non-native algae. The co-occurrence of two invasive Caulerpa species, C. taxifolia var. distichophylla and C. cylindracea in Southern Sicily, offered the possibility to investigate the feeding preferences of a generalist native grazer, the sea urchin Paracentrotus lividus, for native vs non-native food. A multiple choice feeding experiment was set to assess whether and to which extent P. lividus consumes the exotic macroalgae while in presence of the preferred native ones. Multiple choice feeding assays were run with the following food sources simultane…
Co-existing with the alien: evidence for environmental control on trophic interactions between a native (Atherina boyeri) and a non-indigenous fish s…
2022
Biological invasions are a widespread problem worldwide, as invasive non-indigenous species (NIS) may affect native populations through direct (e. g., predation) or indirect (e.g., competition) trophic interactions, leading to changes in the food web structure. The trophic relationships of the invasive eastern mosquitofish Gambusia holbrooki and the native big-scale sand smelt Atherina boyeri coexisting in three Mediterranean coastal ponds characterized by different trophic statuses (from oligotrophic to hypereutrophic) were assessed in spring through isotopic niche analysis and Bayesian mixing models. The two fish relied on the distinctive trophic pathways in the different ponds, with the …
A review on the animal xenodiversity in Sicilian inland waters (Italy)
2015
This paper reviews the available knowledge about faunal xenodiversity in Sicilian inland waters (Italy). The aim is to provide an updated checklist and bibliography of those non-indigenous species (NIS) which occur in the island, and to identify possible threats to its native biological diversity. Data were collected through an extensive literature search which encompassed also local journals, books, congress abstracts, and other grey literature. All the collected data were critically revised and, when possible, verified by consulting available collections or through dedicated sampling surveys. Only those data contained in reports indicating precise occurrence localities, which were confirm…