Francis Marsac

POSTBREEDING MOVEMENTS OF FRIGATEBIRDS TRACKED WITH SATELLITE TELEMETRY

Abstract Using satellite telemetry, we studied the postbreeding movements of Great (Fregata minor) and Magnificent Frigatebirds (F. magnificens) at two breeding colonies in the Indian and Atlantic Oceans. After breeding failure, 67% of the birds with satellite transmitters remained on the breeding colonies and continued to perform foraging trips similar to those undertaken while breeding. Two Magnificent Frigatebirds that bred at a colony off the coast of French Guiana moved west along the coast of South America, and one of the two reached Trinidad 1400 km away. One Great Frigatebird moved 4400 km from Europa Island in the Mozambique Channel to the Maldive Islands. It roosted there for at least four months, making foraging trips of up to 240 km, mainly to an area known for its high concentration of tuna. These results show that frigatebirds are able to make rapid and directed long-distance dispersal movements to other colonies or roosting sites, although the majority of birds remain based on breeding colonies.

Role of pelagic crustaceans in the diet of the longnose lancetfish Alepisaurus ferox in the Seychelles waters

The role of pelagic crustaceans in the diet of the longnose lancetfish Alepisaurus ferox was investigated from stomach content analysis of fish collected in the waters surrounding the Seychelles Archipelago in the western Indian Ocean. Crustaceans accounted for 88.4% by prey number and 73.7% by reconstituted mass during the South-West monsoon season. During the North-East monsoon season, crustaceans remained the main prey group and accounted for 63.7% by prey number and 46% by reconstituted mass. There was a clear seasonal pattern with the portunid crab Charybdis smithii predominating during the South-West monsoon season and the pelagic stomatopod Natosquilla investigatoris during the North-East monsoon season. This pattern likely reflects variations in prey availability linked to current movements around the Seychelles Archipelago. Most of the prey consisted of slow-swimming and small individuals, which occur in dense swarms during the pelagic phase of their life history. The dietary trends of lancetfish are consistent with opportunistic feeding on the most abundant prey. They exploit short food chains based on carnivorous crustaceans, and play an important role in the pelagic trophic functioning of the western Indian Ocean.

Essential ocean variables for global sustained observations of biodiversity and ecosystem changes

Sustained observations of marine biodiversity and ecosystems focused on specific conservation and management problems are needed around the world to effectively mitigate or manage changes resulting from anthropogenic pressures. These observations, while complex and expensive, are required by the international scientific, governance and policy communities to provide baselines against which the effects of human pressures and climate change may be measured and reported, and resources allocated to implement solutions. To identify biological and ecological essential ocean variables (EOVs) for implementation within a global ocean observing system that is relevant for science, informs society, and technologically feasible, we used a driver-pressure-state-impact-response (DPSIR) model. We (1) examined relevant international agreements to identify societal drivers and pressures on marine resources and ecosystems, (2) evaluated the temporal and spatial scales of variables measured by 100+ observing programs, and (3) analysed the impact and scalability of these variables and how they contribute to address societal and scientific issues. EOVs were related to the status of ecosystem components (phytoplankton and zooplankton biomass and diversity, and abundance and distribution of fish, marine turtles, birds and mammals), and to the extent and health of ecosystems (cover and composition of hard coral, seagrass, mangrove and macroalgal canopy). Benthic invertebrate abundance and distribution and microbe diversity and biomass were identified as emerging EOVs to be developed based on emerging requirements and new technologies. The temporal scale at which any shifts in biological systems will be detected will vary across the EOVs, the properties being monitored and the length of the existing time-series. Global implementation to deliver useful products will require collaboration of the scientific and policy sectors and a significant commitment to improve human and infrastructure capacity across the globe, including the development of new, more automated observing technologies, and encouraging the application of international standards and best practices.

A toolkit to study seabird–fishery interactions

A toolkit to study seabird–fishery interactions Tangi Le Bot*, Amélie Lescroël, and David Grémillet Centre d’Ecologie Fonctionnelle et Evolutive, UMR 5175, CNRS—Université de Montpellier—Université Paul-Valéry Montpellier EPHE, Montpellier, France Point Blue Conservation Science, 3820 Cypress Drive, Suite 11, Petaluma, CA 94954, USA Percy FitzPatrick Institute and DST-NRF Centre of Excellence at the University of Cape Town, Rondebosch 7701, South Africa *Corresponding author: tel: þ33 (0) 467 613 309; e-mail: tangi.lebot@cefe.cnrs.fr. Le Bot, T., Lescroël, A., and Grémillet, D. A toolkit to study seabird–fishery interactions. – ICES Journal of Marine Science, 75: 1513– 1525.