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Amandè, M., Chassot, E., Chavance, P., Murua, H., Molina, A. D. de, & Bez, N. (2012). Precision in bycatch estimates : the case of tuna purse-seine fisheries in the Indian Ocean. ICES Journal of Marine Science, 69(8), 1501–1510.
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Assali, C., Bez, N., & Tremblay, Y. (2020). Raking the ocean surface: new patterns of coordinated motion in seabirds. J. Avian Biol., 51(6).
Résumé: Coordinated movements of seabirds exploiting a prey patch are known to increase prey encounter and capture rates of individuals. These behaviours, based on effective cooperation between seabirds, have only been reported at small scale, i.e. the scale of the prey patch. However, the efficient prey exploitation by seabirds in vast oceans require larger scale processes such as information transfers between individuals. Indeed, information transfers between foraging seabirds (e.g. changes in behaviour) reduce their search cost while increasing their prey encounter rate. Whether or not these information transfer processes imply active cooperation is unknown. Using images from fishing boat radars in the eastern tropical Atlantic, we show the existence of frequent medium-scale patterns of coordinated flights of seabird groups, consisting in seabird fronts ('rake' patterns) of 0.3-4.4 km width, displacing cohesively over 1.2-10.6 km and lasting between 2 and 19 min. For these rakes to be maintained, seabird groups have to adjust their flight speeds and directions, while they are on average distant of 500 m from each other, what cannot occur by chance. These findings suggest the existence of collective and coordinated movements in seabirds during prey searching at several kilometres' scale. This potential cooperation between foraging seabird groups brings new insight in the evolutionary trajectories of seabirds life-style.
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Perry, C. T., Alvarez-Filip, L., Graham, N. A. J., Mumby, P. J., Wilson, S. K., Kench, P. S., et al. (2018). Loss of coral reef growth capacity to track future increases in sea level. Nature, 558(7710), 396–+.
Résumé: Sea-level rise (SLR) is predicted to elevate water depths above coral reefs and to increase coastal wave exposure as ecological degradation limits vertical reef growth, but projections lack data on interactions between local rates of reef growth and sea level rise. Here we calculate the vertical growth potential of more than 200 tropical western Atlantic and Indian Ocean reefs, and compare these against recent and projected rates of SLR under different Representative Concentration Pathway (RCP) scenarios. Although many reefs retain accretion rates close to recent SLR trends, few will have the capacity to track SLR projections under RCP4.5 scenarios without sustained ecological recovery, and under RCP8.5 scenarios most reefs are predicted to experience mean water depth increases of more than 0.5 m by 2100. Coral cover strongly predicts reef capacity to track SLR, but threshold cover levels that will be necessary to prevent submergence are well above those observed on most reefs. Urgent action is thus needed to mitigate climate, sea-level and future ecological changes in order to limit the magnitude of future reef submergence.
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