Aim Apical pelagic species forage in predictable habitats, and their movements should signal biologically and ecologically significant areas of the marine ecosystem. Several countries are now engaged in identifying these areas based on animal tracking, but this is often limited to a few individuals from one breeding population , which may result in biased portrayals of the key marine habitats. To help identify such foraging areas, we compiled tracking data of a marine top predator from the main breeding colonies in the Central Macaronesia. Location Northeast Atlantic Ocean. Methods Over seven years, we tracked the foraging movements of Cory's shear-waters (Calonectris borealis) from several populations during the chick-rearing period using global positioning system and platform terminal transmitter devices. Results We obtained foraging trips from 174 shearwaters breeding on six important colonies representative of the range occupied in the Macaronesian Archipelagos of Madeira, Salvages and Canaries. Our results show that birds orient and move rapidly towards the closest neritic waters over the African continental shelf. Birds from different colonies show substantial spatial segregation in their foraging grounds but consistently overlap in some specific foraging areas along the Canary Current characterized by high productivity. By weight-ing the use of foraging grounds according to the size of each study population, we inferred the overall exploitation of such areas. Main conclusions Our meta-population approach provides a more comprehensive picture of space use from both perspectives: the studied species and the Canary Current system. Foraging grounds consistently used by several populations may not be adequately identified by tracking a single population, and therefore, multiple population tracking studies are needed to properly delineate key conservation areas and inform conservation planning in the marine ecosystem. Finally, we highlight the long-term stability and sustainability of identified foraging areas and propose that countries with geographical jurisdictions over the Canary Current area should work towards multilateral agreements to set management plans for this key marine ecosystem.
Individuals within populations can use different resources, leading to ecological segregation and niche variation. This segregation could have direct impacts on the migratory strategy or breeding success, thus affecting the overall population and community dynamics and, ultimately, survival. In this study, we assessed the inter-annual and within individual foraging ecology of an endemic and highly threatened seabird species, the Desertas petrel Pterodroma deserta, during the breeding and non-breeding phases. We combined 54 annual tracks (26 individuals; 2009-2013) obtained with light-level loggers (Global Location Sensing or GLS loggers) with stable isotope analyses (δ 15 N and δ 13 C) of blood (plasma and cells) and feathers. Wide-ranging tracking data show that this species is a generalist predator, able to adapt to very different habitats. All birds remained faithful to their selected non-breeding areas over the years leading to very high spatial, temporal and trophic consistency among years (i.e. usually with intracorrelation coefficient values, which is an index of repeatability of > 40%). During both the breeding and non-breeding seasons, individual birds showed narrow and segregated isotopic niches, indicating a high level of specialization and limited choice of prey and habitats. The conservation of a seabird with such a dispersive (species-level) yet consistent (individual-level) non-breeding distribution pattern represents a challenge in marine policy terms. On the one hand, such a consistent temporal and spatial pattern will help with defining core areas for conservation, which could be protected through specific management measures or by the establishment of marine protected areas. Yet, their relatively large size (on average 4000 km 2 ) and extent over both national and international waters, where different legislative frameworks apply, will require the coordinated action by many nations, international organizations and multilateral environmental agreements.
The little-known Eurasian Sparrowhawk of Macaronesia (Accipiter nisus granti), also named as the Macaronesian sparrowhawk, is endemic to Madeira Island and the Canary Islands (North Atlantic Ocean) and has the smallest area of distribution of the sparrowhawk subspecies. We studied the breeding biology of the Macaronesian sparrowhawk for the first time on Madeira Island, Portugal. Specifically, we described nests, tree nests, nest sites, and nesting territories, and we estimated incubation, hatching and fledging dates. Moreover, we evaluated the influence of altitude on the date of the initiation of breeding and measured the number of fledglings and the factors influencing this parameter. Most nesting territories (88.6%) were located in forest patches where valleys with watercourses were present. Breeding success (73.2% 6 0.1 SE, n ¼ 18) and the mean number of young fledged per nest with eggs (2.27 6 0.04) are lower than the values for the Canary Islands. Altitude influenced the date of the initiation of breeding, with pairs in lowlands (,700 masl) initiating breeding earlier. However, pairs breeding earlier did not have higher reproductive rate than those breeding later. The number of fledglings per nest with eggs in mixed habitats was higher than in exotic and Laurel forests. The main cause of breeding failure was forest cutting. We believe that if the forestry industry does not consider the nesting areas, as well as the breeding phenology of this subspecies, and forest fires are not prevented, then its population in Madeira may be reduced in the near future.
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