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Copyright of Naturaliste Canadien is the property of La Societe Provancher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Indo-Pacific species Avrainvillea amadelpha (Montagne) A. Gepp & E.S. Gepp is reported for the first time from the Mediterranean Sea (Kerkennah Islands, Tunisia). The species is considered as introduced and invasive in the Hawaiian Archipelago. The Mediterranean specimens are studied and the reproductive structures are described and illustrated here for the first time. The possible origins and vectors of this introduction and the risk of propagation of the species in the Mediterranean Sea are discussed. [ABSTRACT FROM AUTHOR]

Biological invasions are a pervasive and dominant form of anthropogenic disturbance. However, we seldom have the opportunity to evaluate the long-term, indirect, and often slow-moving cascading effects of invasions at the community and ecosystem scale. Here we synthesize the collective knowledge from 10 years of study on the influence of the deep historical introduction of coconut palms ( Cocos nucifera L.) across a series of islets at Palmyra Atoll. Through a suite of pathways, we find this palm drives near-complete ecosystem state change when it becomes dominant. Abiotic conditions are transformed, with major soil nutrients 2.7-11.5 times lower and water stress 15% elevated in palm-dominated forests compared with native forest. Faunal communities are likewise dramatically altered, not only in composition but also in behavior, body size, and body condition. Biotic interactions, including herbivory rates, palatability, and seed predation, are likewise changed. Cumulatively, these changes transform food webs, leading to dramatically shortened and simplified food chains in invaded ecosystems. Many of these changes appear to create slow-acting feedback loops that favor the palm at the expense of native species. Given the widespread nature of this historical introduction, many island and coastal regions of tropical oceans may be similarly transformed. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Zoology is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Raccoons ( Procyon lotor (L., 1758)) are known for their dietary plasticity and ability to exploit new resources. We studied raccoons preying on introduced intertidal clams and hypothesized that raccoons maximized energetic profit by foraging selectively. Raccoons discarded Manila clams ( Venerupis philippinarum (A. Adams and Reeve, 1850)) but selected large varnish clams ( Nuttallia obscurata (Reeve, 1857)), although varnish and Manila clam densities did not differ significantly and small varnish clams were more abundant than large ones. We determined the energy content of different-sized varnish and Manila clams by subtracting the cost of cracking a clam from its soft-tissue energy. Varnish clams with less shell mass than Manila clams required less energy to open, but for their size Manila clams were more profitable. We suggest that raccoons, limited to preying on clams when the tide is low and at risk feeding on an open beach, select varnish clams because they need less handling, but maximize profit by selecting large clams. Our calculations indicate that a raccoon eating large varnish clams could obtain up to 8.4% of its daily basal metabolic needs in 10 min, making varnish clams a potentially valuable new prey resource. [ABSTRACT FROM AUTHOR]

Copyright of Biotechnologie, Agronomie, Societe et Environnement is the property of Les Presses Agronomiques de Gembloux and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Biotechnologie, Agronomie, Societe et Environnement is the property of Les Presses Agronomiques de Gembloux and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)