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1. Freshwater fisheries are complex social-ecological systems spatially structured by coupled feedbacks between people and nature. Spatial exploitation dynamics depend on angler preferences for multiple attributes that influence their site choices.Anglers then reciprocally impact local fish populations through size-selective catch and harvest. Thus, feedbacks among angler site choices, their capture efficiency (i.e. catchability) and fish population dynamics permeate through whole landscapes.2. We studied the coupled feedbacks and effects of spatial exploitation in an iconic northern freshwater fishery of conservation concern. Specifically, we evaluated several coupled feedbacks in the spatially structured Yukon lake trout fishery using a Bayesian multinomial choice model fitted to onsite interviews and fishery-independent population assessments to identify whether: (a) trip context (day vs. multi-day trips) shaped angler preferences and site choices, (b) catch-based quality was influenced by a sizenumbers trade-off and density-dependent catchability and (c) fish population structure was associated with the gravity of resource usage resulting from spatial exploitation.3. Overall, we found that angler site choices were shaped by preferences for multiple characteristics including travel time and catch-based quality. Angler preferences also varied with trip contexts-for example, anglers on day trips were less willing to travel than anglers on multi-day trips. We detected strong density-dependent catchability, which led to hyperstable catches and relatively few anglers dominated most of the catch.4. There was a strong demographic trade-off between lake trout body size and abundance that appeared to dynamically interact with anglers' size-selective preferences for larger lake trout. Coupled feedbacks among angler site choices, sizeselective and hyperstable catches, and density-dependent growth and survival appeared to structure spatial exploitation patterns leading to a halo of depletion in fish body sizes and fishing quality near urban centres. Synthesis and applications.Feedbacks between fish and anglers affected spatial exploitation patterns leading to a halo of depletion in Yukon lake trout. We recommend | 207Journal of Applied Ecology WILSON et aL.

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Plasticity, local adaptation and evolutionary trade‐offs drive clinal variation in traits associated with lifetime growth. Disentangling the processes and determinants that cause these traits to vary helps to understand species’ responses to changing environments. This is particularly urgent for exploited populations, where size‐selective harvest can induce life‐history evolution. Lake trout (Salvelinus namaycush) are an exploited fish with a life history adapted to low‐productivity freshwaters of northern North America, which makes them highly vulnerable to ecosystem changes and overfishing. We characterized life‐history variation across a broad and diverse landscape for this iconic northern freshwater fish and evaluated whether clinal variation was consistent with hypotheses for local adaptation or growth plasticity. We estimated growth‐associated traits for 90 populations exposed to a diversity of environments using a Bayesian multivariate hierarchical model. We tested for clinal variation in their somatic growth, size at maturity and reproductive allocation along environmental gradients of lake productivity, climate, prey and exploitation clines under competing hypotheses of plasticity and local adaptation. Clinal life‐history variation was consistent with growth plasticity and local adaptations but not harvest‐induced evolution. Variation in somatic growth was explained by exploitation, climate and prey fish occurrence. Increased exploitation, from pristine to fully exploited conditions, led to increased somatic growth (from 32 to 45 mm/year) and adult life spans, and reduced age at maturity (from 11 to 8 years). Variation in size at maturity was explained by climate and, less certainly, prey fish occurrence, while reproductive allocation was explained by evolutionary trade‐offs with mortality and other traits, but not environment. Lake trout life‐history variation within this range was as wide as that observed across dozens of other freshwater species. Lake trout life histories resulted from evolutionary trade‐offs, growth plasticity and local adaptations along several environmental clines. Presuming a plastic response, we documented ~1.4‐fold growth compensation to exploitation—lower growth compensation than observed in many freshwater fishes. These results suggest that harvested species exposed to spatially structured and diverse environments may have substantial clinal variation on different traits, but due to different processes, and this has implications for their resilience and successful management.