Search results for "Caulerpa"

ARE MARINE PROTECTED AREAS (MPAs) EFFECTIVE IN PROTECTING FROM INVASIVE SPECIES? THE CASE STUDY OF CAULERPA CYLINDRACEA SONDER (CAULERPALES, CHLOROPH…

2019

The main purpose of Marine Protected Areas (MPAs) is biodiversity conservation. The effects that invasive species have on MPAs, and vice versa, are still not completely known, even though their assessment is crucial for MPA management and conservation purposes. In this respect, monitoring plans are essential and the involvement of citizen scientists may be fundamental. Our experience of Caulerpa cylindracea Sonder 1845 monitoring within the Egadi Islands MPA highlighted that the alga is widespread within the MPA, mainly at Favignana Island, also threatening valuable habitats such as vermetid reef and coralligenous formations. Moreover, Favignana is the island of the Aegadian archipelago mos…

An updated overview of invasive Caulerpa taxa in Sicily and circum- Sicilian Islands, strategic zones within the NW Mediterranean Sea

2017

The spread dynamics of invasive Caulerpa taxa (i.e. Caulerpa cylindracea, C. taxifolia var. taxi- folia and C. taxifolia var. distichophylla) in Sicily and circum-Sicilian Islands, based on relevant publications, grey literature, unpublished data and in situ observations during the last 23 years, is presented here and discussed. Their known distribution is mapped. New records are also reported. Transport-stowaway is considered the most plausible vector of introduction of invasive Caulerpa in the area. The three invasive taxa showed different spread dynamics. Caulerpa cylindracea and C. taxifolia var. distichophylla, behaved as highly successful and fast-spreading taxa, i.e. as true invasive…

Nuove segnalazioni di Caulerpa racemosa var. cylindracea in aree protette della Sicilia nord-occidentale

2008

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…

Caulerpa racemosa var. cylindracea as a potential source of organic matter for benthic consumers: evidences from a stable isotope analysis.

2008

Caulerpa racemosa var. cylindracea has been invading various types of substrates in wide areas throughout the Mediterranean Sea. However, the effects of the distribution of this alga on zoobenthos are scanty. The aim of this study was to evaluate the effects of C. racemosa invasion on the feeding habits of some zoobenthic taxa inhabiting the upper infralittoral rocky shores. This was done by identifying the isotopic N and C ratios of several potential food sources and testing differences in isotope composition among the taxa collected from areas invaded and not-invaded areas by C. racemosa. Results suggest that C. racemosa detritus was a significant food source for the polychaete Syllis pro…

Hiding behaviour ofOxynoe olivacea(Mollusca: Opisthobranchia: Sacoglossa) in the invasive seaweedCaulerpa taxifolia

2013

The occurrence of the invasive seaweed Caulerpa taxifolia in the Straits of Messina (Italy) provides an excellent opportunity to examine the spatial and temporal patterns of abundance of the endemic Mediterranean sacoglossan Oxynoe olivacea. Densities of this species were recorded in March, June and October 2000 on three different habitats: the underside of boulders (UNB), the upper side of boulders (UPB), and the surface of concrete blocks (CB). Results showed that in March, O. olivacea was consistently more abundant on UNB whereas in June it was present exclusively on CB. The density of O. olivacea was similar in the three habitats in October. The hiding behaviour of O. olivacea and its s…

Origin and distribution of suspended organic matter as inferred from carbon isotope composition in a Mediterranean semi-enclosed marine system

1999

The origin and distribution of suspended organic matter, the trophic features and the stable carbon isotopic composition of particulate organic carbon (POC) were studied monthly in a Western Mediterranean semi-enclosed basin. Sampling stations were selected as a function of wind-exposure and the degree of vegetation cover and then compared with an adjacent unvegetated site. The predominant vegetation was seagrass (Posidonia oceanica and Cymodocea nodosa) and Caulerpa prolifera. Water samples were analyzed for total suspended matter (inorganic and organic fractions), photosynthetic pigments (chlorophyll-a and phaeopigments), dissolved organic carbon, particulate organic carbon and their isot…

Feeding strategy of the sacoglossan opisthobranch Oxynoe olivacea on the tropical green alga Caulerpa taxifolia.

2007

The feeding behaviour of the shelled sacoglossan Oxynoe olivacea was investigated to better understand the role and importance of this species in influencing encroachments of the alien alga Caulerpa taxifolia in the Mediterranean sea. We tested whether this slug preferred, as preliminary field observations suggested, an aggregative feeding behaviour and which part of the algal thallus, phylloid vs rhizoid, it preferred. Results showed that O. olivacea fed in groups and actively selected phylloid. This outcome poses important questions regarding the possibility that this species, fragmenting the alga thallus, could enhance dispersion and regeneration of C. taxifolia.

Typification of the marine siphonous green algae Caulerpa prolifera (Bryopsidales, Chlorophyta)

2015

The typification of the marine siphonous green algae Caulerpa prolifera (Forsskål) J.V. Lamouroux (≡ Fucus prolifer Forsskål) (Caulerpaceae), including f. obovata (J. Agardh) Weber-van Bosse and f. zosterifolia Børgesen, is discussed. Original material conserved in the Natural History Museum of Denmark (Copenhagen) at C (Herbarium Forsskålii) and in the Botanical Museum of Lund University at LD are designated as the corresponding lectotypes.

Effects of Caulerpa cylindracea Sonder (Chlorophyta Caulerpaceae) on marine biodiversity

2019

The chief purpose of Marine Protected Areas (MPAs) is biodiversity conservation. The effects that invasive alien species (IAS) have on MPAs are not yet fully known, even though assessing them is fundamental. Effective management plans, indeed, also require knowledge on the dis- tribution, spread dynamics and impact of IAS. We report first observations on the effects of Caulerpa cylindracea Sonder (Chlorophyta Caulerpaceae) on the communities living along the coasts of the Island of Favignana (Egadi Islands MPA, Sicily, Italy). We found that C. cylindracea may have negative effects on the habitat where it settles in two different ways: a) affecting the structure of the native algal community…