DOP - Artigos em Revistas Internacionais / Articles in International Journals
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Browsing DOP - Artigos em Revistas Internacionais / Articles in International Journals by Author "Bried, Joël"
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- Depredation of Monteiro's Storm-petrel (Hydrobates monteiroi) Chicks by Madeiran Wall Lizard (Lacerta dugesii)Publication . Neves, Verónica C.; Nava, Cristina; Monteiro, Eva; Monteiro, Paulo R.; Bried, JoëlMonteiro’s Storm-petrel (Hydrobates monteiroi) is a small seabird endemic to the Azores archipelago, where it is known to breed only on two mammal-free islets. Total breeding numbers are between 250 and 300 pairs. During the 2015 breeding season on Praia Islet, six Madeiran wall lizards (Lacerta dugesii) were observed depredating a Monteiro’s Storm-petrel chick about to fledge. In August 2015, a freshly killed chick without its head and four larger dead chicks were found. Eight other chicks had disappeared from their nests since our previous visit in early July. In 2016, there was further evidence of suspected lizard depredation. Three chicks were found predated and dragged out of their nests, and an additional 22 chicks disappeared from their nests before fledging. In 2016, Monteiro’s Storm-petrel breeding success was only 26.8%, the lowest ever recorded. We suspect that some of the chick deaths and nest failures may be attributable to these introduced lizards. All chicks were found dragged out of their nests, a behavior that is not consistent with kills from aerial predators. Lizards were suspected because they are the only possible predator on land. Therefore, we recommend evaluating the impact of Madeiran wall lizards on the two Monteiro’s Storm-petrel main colonies: Praia and baixo islets.
- Leapfrog migration and habitat preferences of a small oceanic seabird, Bulwer's petrel (Bulweria bulwerii)Publication . Ramos, Raül; Sanz, Víctor; Militão, Teresa; Bried, Joël; Neves, Verónica C.; Biscoito, Manuel; Phillips, Richard A.; Zino, Francis; González-Solís, JacobAIM: Our current understanding of migratory strategies and the reasons for their high variability along the phylogenetic tree remains relatively poor. Most of the hypotheses relating to migration have been formulated for terrestrial taxa; classically, oceanic migrations were considered as merely dispersive because of the scarcity of observations in the open ocean. We describe for the first time, the migration strategy of a small seabird, the Bulwer's petrel (Bulweria bulwerii), and provide new insights into the ecology and evolution of long-distance marine migrations. LOCATION: Subtropical and tropical Atlantic Ocean. METHODS: Using cutting-edge geolocators, we examined the year-round distribution and at-sea activity patterns of adult Bulwer's petrels sampled at five localities throughout the species' breeding range in the Atlantic, within the Azores, Salvages, Canary and Cape Verde archipelagos. We assessed the migratory connectivity of the species and its habitat use at population and metapopulation scales. RESULTS: Our results provide the first evidence of an oriented leapfrog migration in oceanic seabirds. Ecological niche models based on breeding-season data effectively predicted that subtropical waters of the South Atlantic would be the preferred habitat for the northern populations of Bulwer's petrels during the non-breeding season. Habitat modelling also highlighted similarities in distributions between the breeding and non-breeding periods for the southern populations. Data on at-sea activity patterns suggested that birds from the northern and southern populations behave differently during the breeding season, as well as in the northern and southern non-breeding ranges during the non-breeding period. MAIN CONCLUSIONS: These results indicate that specific habitat preferences, presumably related to differences in prey availability, explain the observed distributions and hence the pattern of leapfrog migration described for Bulwer's petrel. Our study demonstrates the utility of integrating diverse tracking data from multiple populations across international boundaries, and habitat modelling, for identifying important areas common to many marine species in the vast oceanic environments.
- Reduced population size does not affect the mating strategy of a vulnerable and endemic seabirdPublication . Nava, Cristina; Neves, Verónica C.; Andris, Malvina; Dubois, Marie-Pierre; Jarne, Philippe; Bolton, Mark; Bried, JoëlBottleneck episodes may occur in small and isolated animal populations, which may result in decreased genetic diversity and increased inbreeding, but also in mating strategy adjustment. This was evaluated in the vulnerable and socially monogamous Monteiro's Storm-petrel Hydrobates monteiroi, a seabird endemic to the Azores archipelago which has suffered a dramatic population decline since the XVth century. To do this, we conducted a genetic study (18 microsatellite markers) in the population from Praia islet, which has been monitored over 16 years. We found no evidence that a genetic bottleneck was associated with this demographic decline. Monteiro's Storm-petrels paired randomly with respect to genetic relatedness and body measurements. Pair fecundity was unrelated to genetic relatedness between partners. We detected only two cases of extra-pair parentage associated with an extra-pair copulation (out of 71 offspring). Unsuccessful pairs were most likely to divorce the next year, but genetic relatedness between pair mates and pair breeding experience did not influence divorce. Divorce enabled individuals to improve their reproductive performances after re-mating only when the new partner was experienced. Re-pairing with an experienced partner occurred more frequently when divorcees changed nest than when they retained their nest. This study shows that even in strongly reduced populations, genetic diversity can be maintained, inbreeding does not necessarily occur, and random pairing is not risky in terms of pair lifetime reproductive success. Given, however, that we found no clear phenotypic mate choice criteria, the part played by non-morphological traits should be assessed more accurately in order to better understand seabird mating strategies.