0000000001095766
AUTHOR
Simona Noè
Food selection of a generalist herbivore exposed to native and alien seaweeds
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…
Synergistic reduction of a native key herbivore performance by two non-indigenous invasive algae
Abstract Native generalist grazers can control the populations of non-indigenous invasive algae (NIIA). Here, it was found that the simultaneous consumption of two co-occurring NIIA, Caulerpa cylindracea and C. taxifolia var. distichophylla, hinders the grazing ability of the main Mediterranean herbivorous, the native sea urchin Paracentrotus lividus. The ingestion of any of the two NIIA alone did not produce any difference in sea urchin righting time with respect to usual algal diet. In contrast, the simultaneous consumption of both NIIA, which grow intermingled in nature and are consumed by P. lividus, retarded its righting behavior. Such result reveals substantial physiological stress in…
The role of Marine Protected Areas in influencing the invasion success of the alien crab Percnon gibbesi
The biotic resistance hypothesis states that pristine communities, with high species richness and functional diversity, are less prone to biological invasions than species-poor areas either this is natural or it is a result of human activities. Complex communities with high levels of biodiversity, such as those hosted by Marine Protected Areas, should offer fewer niche opportunities (e.g. resources and space) to invasive species thereby reducing both their establishment possibilities and success (i.e. settlement and/or expansion). The present study aimed to evaluate the capacity of marine protected communities to provide a buffer against the establishment of one of the most invasive species…
Native predators control the population of an invasive crab in no-take marine protected areas
1. The resistance of an ecosystem to species invasion is considered to be related to the abundance and diversity of native species i.e. biotic resistance hypothesis). Theory predicts that the high native diversity in pristine systems can hinder the establishment and/or the spread of non‐native species through direct and indirect mechanisms (e.g. through competitive and/or predatory interactions). 2. Here we tested whether predation provides higher resistance to invasion by the Percnidae crab Percnon gibbesi (H. Milne Edwards, 1853) in protected native communities, compared with exploited ones. Specifically, this study aimed to compare: (i) the abundance and diversity of potential predator a…
Chemoecological study of the invasive alga Caulerpa taxifolia var. distichophylla from the Sicilian coast
Marine invasive species and their bioactive metabolites have become critical ecological issues in the Mediterranean Sea. In particular, the highly invasive green algae Caulerpa taxifolia and Caulerpa cylindracea are known to contain the bioactive sesquiterpene caulerpenyne (1) and the bisindolic alkaloid caulerpin (2), potentially acting as chemical stressors for native species. The recent spread of a variety of C. taxifolia, Caulerpa taxifolia var. distichophylla, also raises urgent questions about its chemical composition. Indeed, the only chemical data available for this alga are limited to the seasonal variations of caulerpenyne (1) in samples collected in the Eastern Mediterranean. In …
Resilience of the seagrass Posidonia oceanica following pulse-type disturbance.
Understanding the response of species to disturbance and the ability to recover is crucial for preventing their potential collapse and ecosystem phase shifts. Explosive submarine activity, occurring in shallow volcanic vents, can be considered as a natural pulse disturbance, due to its suddenness and high intensity, potentially affecting nearby species and ecosystems. Here, we present the response of Posidonia oceanica, a long-lived seagrass, to an exceptional submarine volcanic explosion, which occurred in the Aeolian Archipelago (Italy, Mediterranean Sea) in 2002, and evaluate its resilience in terms of time required to recover after such a pulse event. The study was carried out in 2011 i…
Role of interspecific interactions in biological invasions: new evidence from the Mediterranean Sea
Despite the field of invasion ecology has rapidly grown, the mechanisms behind the invasion success of alien species and the biotic resistance to invasions still need a thorough understanding. Comprehending the response of resident assemblages to biological invasions and the possible impacts produced by alien species introduction is, therefore, crucial to expand the current knowledge of the invasion process in the recipient systems. In this thesis different aspects of biological invasion process have been critically examined emphasizing the importance and complexity of the interactions between alien species and native biota, in the Mediterranean marine coastal ecosystems. Here, five differe…