Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Biofouling increases the operational and economic costs associated with pearl production. As currentprocedures for reducing oyster biofouling can be detrimental to survival and growth and may pollute thesurrounding environment developing alternative, biologically-mediated, methods could potentially in-crease both production and ecological sustainability. With this in mind, the present study investigatednatural cleaning of black-lipped pearl oysters, Pinctada margaritifera, by butterflyfishes (Chaetodon). Thefeeding behaviour of six butterflyfish species was examined at Rangiroa Atoll, French Polynesia: Chae-todon auriga, Chaetodon citrinellus, Chaetodon ephippium, Chaetodon lunulatus, Chaetodon trifascialis andChaetodon ulietensis. All species cleaned the surface of pearl oysters by removing epibionts (from 16% to40% of total biomass), although dietary variation may explain different cleaning efficiencies. Generalistomnivores (C. auriga, C. citrinellus, C. ephippium and C. ulietensis) were the most efficient cleaners (%cleaning range: 26e40% of total biomass). Within this group, C. ephippium removed the most biomass(average of 41%) targeting algae and anemones. However, C. auriga targeted the most diverse range ofepibionts, removing significant amounts of algae, sponges, tunicates, and anemones. These resultssuggest that foraging by butterflyfishes can substantially reduce biofouling on economically-importanttropical bivalves.
ISSN: 0272-7714

hal-01434152
https://hal-univ-perp.archives-ouvertes.fr/hal-01434152
DOI : 10.1016/j.ecss.2016.04.001

Éditeur(s) : Université des Antilles Études caribéennes
Résumé : The quality of the natural environment is inexorably linked to tourism in the Caribbean. Tourists are attracted to the beauty of the Caribbean coastal and marine environment, generating significant economic activity and employment. The resulting development and concentration of human activities in the coastal zone may have deleterious effects on environmental quality and tourists’ willingness to return. Using a survey administered to over 2,000 tourists in Barbados, this work examines tourist perceptions of beach quality and encounters with beach litter. The relationship between the quality of the coastal environment and the probability of return visitation is empirically investigated. Results demonstrate a clear link between viewing beach litter and the perceived quality of beaches and that tourists who stayed beachfront or in large hotels encountered significantly less beach litter and had higher ratings of beach quality. The amount of litter viewed and stated perceptions of beach quality are significantly associated with the probability of return visitation, especially for first-time visitors. Results of this study suggest that targeted beach clean-up efforts may enhance the probability of return visitation and create significant economic value.
La qualité de l'environnement naturel est inexorablement liée au tourisme dans les Caraïbes. Les touristes sont attirés par la beauté de la côte des Caraïbes et du milieu marin, stimulant l'activité économique et l'emploi. Le développement qui en résulte et la concentration des activités humaines dans la zone côtière peuvent avoir des effets délétères sur la qualité de l'environnement et de la volonté des touristes à revenir. L'utilisation d'un sondage mené auprès de plus de 2.000 touristes à la Barbade examine les perceptions touristiques de la qualité des plages et des rencontres avec des déchets sur les plages. La relation entre la qualité de l'environnement côtier et la probabilité du retour des visiteurs est une étude empirique. Les résultats montrent un lien clair entre la visualisation des déchets sur les plages, la qualité perçue des plages et le lieu de séjour des touristes en bord de mer, dans les grands hôtels, selon la qualité plus ou moins élevées de la plage. La quantité de litière vue et la déclaration du degré de qualité des plages perçue sont significativement associées à la probabilité de retour des visiteurs, en particulier pour les primo-visiteurs. Les résultats de cette étude suggèrent que les efforts de nettoyage sur les plages cibles peut augmenter la probabilité de retour de visiteurs et de créer une valeur économique significative.
Barbade

Droits : info:eu-repo/semantics/openAccess
urn:doi:10.4000/etudescaribeennes.5251
http://journals.openedition.org/etudescaribeennes/5251

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : Background. In wild plant populations, genetic divergence within continuous stands is common, sometimes at very short geographical scales. While restrictions to gene flow combined with local inbreeding and genetic drift may cause neutral differentiation among subpopulations, microgeographical variations in environmental conditions can drive adaptive divergence through natural selection at some targeted loci. Such phenomena have recurrently been observed in plant populations occurring across sharp environmental boundaries, but the interplay between selective processes and neutral genetic divergence has seldom been studied.[br/]Methods. We assessed the extent of within-stand neutral and environmentally-driven divergence in the Neotropical tree [i]Eperua falcate Aubl[/i]. (Fabaceae) through a genome-scan approach. Populations of this species grow in dense stands that cross the boundaries between starkly contrasting habitats. Within-stand phenotypic and candidate-gene divergence have already been proven, making this species a suitable model for the study of genome-wide microgeographic divergence. Thirty trees from each of two habitats (seasonally flooded swamps and well-drained plateaus) in two separate populations were genotyped using thousands of AFLPs markers. To avoid genotyping errors and increase marker reliability, each sample was genotyped twice and submitted to a rigorous procedure for data cleaning, which resulted in 1196 reliable and reproducible markers.[br/]Results. Despite the short spatial distances, we detected within-populations genetic divergence, probably caused by neutral processes, such as restrictions in gene flow. Moreover, habitat-structured subpopulations belonging to otherwise continuous stands also diverge in relation to environmental variability and habitat patchiness: we detected convincing evidence of divergent selection at the genome-wide level and for a fraction of the analyzed loci (comprised between 0.25% and 1.6%). Simulations showed that the levels of differentiation for these outliers are compatible with scenarios of strong divergent selection
ISSN: 1932-6203

hal-01204220
https://hal.archives-ouvertes.fr/hal-01204220
https://hal.archives-ouvertes.fr/hal-01204220/document
https://hal.archives-ouvertes.fr/hal-01204220/file/journal.pone.0121394.PDF
PRODINRA : 287494