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International audience; Mangroves are critically important habitats for fisheries, bothfor their resident fish, crustacean, and mollusk populations and as nurserygrounds for the target species of offshore fisheries. However, the spatial variationin the benefits provided by mangroves to fisheries is poorly understood.Based on expert knowledge of mangrove ecology and fisheries biology, we developeda preliminary model of the spatial distribution of benefits to fisheriesfrom mangroves. The preliminary model covers the environmental factors thatdetermine the amount of fish, crustaceans, mollusks, and other fishery targetspecies produced by mangrove areas (termed “potential fish production”) andthe socioeconomic variables that determine the level of fishing in any given location.The combination of these two outputs gives the predicted catch. Potentialfish production is predicted to be highest where there is high freshwater andnutrient input to mangroves, such as in large estuaries. At large seascape scales,total mangrove area is also an important driver. Fishing effort is highest closeto human populations, which provide both the fishers and the markets for theircatch. The model is qualitative and has not been parameterized with field dataand, as such, should only be considered as a first step towards understandingthe spatial variation in the benefits that mangroves provide to fisheries.

Stress can have sublethal effects that are manifested either immediately or at spatial or temporal scales that are removed from the stress event (i.e., carryover effects). We tested whether a short-term elevation of plasma cortisol would result in seasonal carryover effects in wild largemouth bass Micropterus salmoides. Using exogenous hormone implants, we raised circulating cortisol concentrations in a group of wild fish for approximately 5 d in October 2007. We then compared activity (velocity, distance traveled) of cortisol-treated animals with that of sham-treated and control animals throughout the winter using an automated acoustic telemetry array. Immediately following treatment, the cortisol-treated fish showed increased activity relative to controls. However, this difference disappeared following the cessation of the elevation of circulating cortisol. During the winter of 2007 to 2008, the lake experienced a nearly complete winterkill event, providing insight into how a transient stress response can influence the response of wild animals to subsequent challenges. Most fish carrying acoustic transmitters succumbed during this winterkill event, but cortisol-treated fish died earlier than fish in other groups and showed a decrease in activity relative to controls and sham-treated fish before mortality. This study provides preliminary evidence of seasonal carryover effects in wild fish and yields insight into the ecological consequences of stress across broad temporal scales. This research was supported by Natural Sciences and Engineering Research Council discovery grants to S.J.C. and K.M.G., the projects Adaptfish (Gottfried-Wilhelm-Leibniz-Community, http://www.adaptfish.igb-berlin.de) and Besatzfisch (German Ministry for Education and Research, Program on Social-Ecological Research, grant 01UU0907, http://www.besatz-fisch.de) to R.A., and a Research Achievement Award from Carleton University to S.J.C. The lead author was supported by a Fisheries Research Award from the Ontario Federation of Anglers and Hunters, an Ontario Graduate Scholarship in Science and Technology, and by Carleton University." https://www.journals.uchicago.edu/doi/abs/10.1086/656286