Dear colleagues, I am glad to inform you that a new article is now available online: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0062180 *The Stranding Anomaly as Population Indicator: The Case of Harbour Porpoise /Phocoena phocoena/ in North-Western Europe.* Helene Peltier, Hans J. Baagøe,Kees C. J. Camphuysen,Richard Czeck,Willy Dabin,Pierre Daniel,Rob Deaville,Jan Haelters,Thierry Jauniaux,Lasse F. Jensen,Paul D. Jepson,Guido O. Keijl,Ursula Siebert,Olivier Van Canneyt,Vincent Ridoux * *Abstract: Ecological indicators for monitoring strategies are expected to combine three major characteristics: ecological significance, statistical credibility, and cost-effectiveness. Strategies based on stranding networks rank highly in cost-effectiveness, but their ecological significance and statistical credibility are disputed. Our present goal is to improve the value of stranding data as population indicator as part of monitoring strategies by constructing the spatial and temporal null hypothesis for strandings. The null hypothesis is defined as: small cetacean distribution and mortality are uniform in space and constant in time. We used a drift model to map stranding probabilities and predict stranding patterns of cetacean carcasses under H_0 across the North Sea, the Channel and the Bay of Biscay, for the period 1990--2009. As the most common cetacean occurring in this area, we chose the harbour porpoise /Phocoena phocoena/ for our modelling. The difference between these strandings expected under H_0 and observed strandings is defined as the stranding anomaly. It constituted the stranding data series corrected for drift conditions. Seasonal decomposition of stranding anomaly suggested that drift conditions did not explain observed seasonal variations of porpoise strandings. Long-term stranding anomalies increased first in the southern North Sea, the Channel and Bay of Biscay coasts, and finally the eastern North Sea. The hypothesis of changes in porpoise distribution was consistent with local visual surveys, mostly SCANS surveys (1994 and 2005). This new indicator could be applied to cetacean populations across the world and more widely to marine megafauna. All the best Helene Peltier -- Hélène PELTIER -PhD Observatoire PELAGIS UMS 3462 Université de La Rochelle-CNRS 5, allées de l'océan 17000 La Rochelle, France hpeltier@univ-lr.fr +33 (0) 16 49 67 82 /+33 (0) 6 82 74 08 41