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The geographical range of schistosomiasis is affected by the ecology of schistosome parasites and their obligate host snails, including their response to temperature. Previous models predicted schistosomiasis’ thermal optimum at 21.7°C, which is not compatible with the temperature in sub-Saharan Africa (SSA) regions where schistosomiasis is hyperendemic. We performed an extensive literature search for empirical data on the effect of temperature on physiological and epidemiological parameters regulating the free-living stages ofS.mansoniandS.haematobiumand their obligate host snails, i.e.,Biomphalariaspp. andBulinusspp., respectively. We derived nonlinear thermal responses fitted on these data to parameterize a mechanistic, process-based model of schistosomiasis. We then re-cast the basic reproduction number and the prevalence of schistosome infection as functions of temperature. We found that the thermal optima for transmission ofS.mansoniandS.haematobiumrange between 23.1–27.3°C and 23.6–27.9°C (95% CI) respectively. We also found that the thermal optimum shifts toward higher temperatures as the human water contact rate increases with temperature. Our findings align with an extensive dataset of schistosomiasis prevalence in SSA. The refined nonlinear thermal-response model developed here suggests a more suitable current climate and a greater risk of increased transmission with future warming for more than half of the schistosomiasis suitable regions with mean annual temperature below the thermal optimum. 

Abstract Fisheries are often characterized by high heterogeneity in the spatial distribution of habitat quality, as well as fishing effort. However, in several fisheries, the objective of achieving a sustainable yield is addressed by limiting Total Allowable Catch (TAC), set as a fraction of the overall population, regardless of the population's spatial distribution and of fishing effort. Here, we use an integral projection model to investigate how stock abundance and catch in the green abalone fishery in Isla Natividad, Mexico, are affected by the interaction of heterogeneity in habitat quality and fishing effort, and whether these interactions change with Allee effects—reproductive failure in a low-density population. We found that high-quality areas are under-exploited when fishing pressure is homogeneous but habitat is heterogeneous. However, this leads to different fishery outcomes depending on the stock's exploitation status, namely: sub-optimal exploitation when the TAC is set to maximum sustainable yield, and stability against collapses when the fishery is overexploited. Concentration of fishing effort in productive areas can compensate for this effect, which, similarly, has opposite consequences in both scenarios: fishery performance increases if the TAC is sustainable but decreases in overexploited fisheries. These results only hold when Allee effects are included.