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Stable hydrogen isotopes ([delta]D) can help predict geographic origin of tissue growth but within-site variation of feather [delta]D([delta][D.sub.f]) exists. Multiple hypotheses explain [delta][D.sub.f] variation: moult timing, physiology, and spatio-temporal differences in source deuterium, but there have been few direct tests of these factors. We assessed [delta][D.sub.f] variation within a breeding population of Wood Thrush (Hylocichla mustelina (Gmelin, 1789)), by sampling feathers from hatch-year birds, returning adults (after migration), and to eliminate confounding variables from newly grown adult primary feathers during moult. We evaluated potential mechanisms explaining [delta][D.sub.f] variation by examining intraindividual variation (different feather types), precipitation [delta]D, prey [delta]D, corticosterone (CORT), and breeding productivity. In addition, we directly compared [delta][D.sub.f] of newly grown primary feathers to [delta]D blood hematocrit ([delta][D.sub.b]). We found significant differences in [delta][D.sub.f] between years and age classes and observed no significant intraindividual variation. [delta][D.sub.f] and [delta][D.sub.b] were not significantly correlated. CORT weakly contributed to [delta][D.sub.f], but there are other factors influencing [delta][D.sub.f]. Ten percent of all feather samples had outlying [delta][D.sub.f] values, and were likely grown away from the breeding grounds. Our results document intrapopulation and intraindividual variation of [delta][D.sub.f] at a single location and indicated that age class and year-to-year differences contributed to high [delta][D.sub.f] variance. Key words: deuterium variation, feathers, moult, precipitation, blood hematocrit, Wood Thrush, Hylocichla mustelina. Si les isotopes stables de l'hydrogene ([delta]D) peuvent aider a predire l'origine geographique de la croissance tissulaire, des variations existent au sein de localites donnees. Plusieurs hypotheses pourraient expliquer ces variations de [delta][D.sub.f], dont le moment de la mue, la physiologie et des differences spatiotemporelles du deuterium source. Ces facteurs ont toutefois fait l'objet de peu de tests directs. Les variations de [delta][D.sub.f] au sein d'une population nicheuse de grives des bois (Hylocichla mustelina (Gmelin, 1789)) ont ete evaluees en echantillonnant des plumes d'oiseaux de l'annee et d'adultes de retour (apres la migration), afin d' eliminer les variables confusionnelles associees aux nouvelles plumes primaires adultes apparues durant la mue. Les mecanismes pouvant expliquer les variations de [delta][D.sub.f] ont ete evalues en examinant les variations intraindividuelles (differents types de plumes), le [delta]D des precipitations, le [delta]D des proies, la corticosterone (CORT) et la productivite de la reproduction. Le [delta][D.sub.f] de nouvelles plumes primaires a en outre ete compare directement au [delta][D.sub.f] de l' hematocrite ([delta][D.sub.b]). Des differences significatives de [delta][D.sub.f] ont ete relevees d'une annee a l'autre et entre les classes d'age, mais aucune variation intraindividuelle significative n'a ete observee. [delta][D.sub.f] et [delta][D.sub.b] n' etaient pas correles de maniere significative. Si la CORT contribuait faiblement au [delta][D.sub.f],d'autres facteurs l'influencaient egalement. Dix pour cent de tous les echantillons de plumes presentaient des valeurs de [delta][D.sub.f] aberrantes et avaient probablement pousse en dehors de l'aire de nidification. Les resultats font etat de variations intrapopulation et intraindividuelles de [delta][D.sub.f] en un seul et meme site et indiquent que la classe d'age et les differentes interannuelles ont contribue a la forte variance des valeurs de [delta][D.sub.f]. Mots-cles: variations du deuterium, plumes, mue, precipitations, hematocrite, grive des bois, Hylocichla mustelina. [Traduit par la Redaction], Introduction Stable hydrogen isotope analysis of feathers ([delta][D.sub.f])has become widespread in studies on avian migration and dispersal and has revolutionized our understanding of animal movements in a wide range of [...]

A novel protocol was developed for ecological prioritization of coral reefs for inclusion in a marine reserve network. Standard benthic survey data were normalized and combined in a conservation priority index (CPI) which rates individual candidate sites according to their ecological values and their potential contributions to an effective network., The CPI differentiates between sites on the basis of strength or weakness of surrogates for desirable attributes such as benthic biodiversity, reef-building capacity and hard-coral resilience., Biodiversity and reef-building attributes (more is better) were assigned progressive weightings (high abundance, high score), whereas neutral or detrimental attributes (less is better) were assigned regressive weightings (high abundance, low score)., Abundance of small corals (new recruits and remnants) was included as an indicator of a site's potential for recovery following disturbance., The CPI rankings were used in conjunction with multidimensional scaling to prioritize candidate sites for a proposed reserve network near Salvador, Brazil. The information is complementary to considerations of existing uses and socio-economic considerations, in the prioritization of reefs for protection., The approach ensured that ecological inputs to the broader marine spatial planning process embraced both representativeness of biodiversity per se and the investigator's evaluation of key qualitative site attributes (amount, size, and resilience indicators for the critical architectural components hard coral and encrusting coralline algae)., Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Species richness, cover and community structure of reef-building corals were assessed at 599 sites on 135 reefs along the Great Barrier Reef (GBR) between 1994 and 2001, with focus on the nearshore area. Communities were described hierarchically, with smaller regional communities forming part of higher level communities at increasing spatial scales. Site richness increased from the coast to the mid-continental shelf, declining on the outer shelf. Richness also increased with depth to 5 m, stabilizing thereafter. An anomaly was present in a 400 km section adjacent to the northern, 'wet tropics' coast, where site richness was 67 and 41% lower than the adjacent far northern and central GBR, respectively; this was probably due to the disturbance regime, with an apparent anthropogenic component. Site richness also declined in the Southern GBR, probably due to naturally marginal conditions. All indicator species had highest values in five small Far Northern and Central GBR communities. In the eight depauperate communities no indicator species had high values, indicating that these communities represent degraded, yet potentially transitional forms of the more diverse communities of the Far Northern and Central GBR. The study shows that on the GBR, disturbance results in the local removal of corals rather than a shift to suites of other coral species. [ABSTRACT FROM AUTHOR]