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Rising global seafood demand poses increasing challenges for sustainable fishery management. This is particularly the case in the Global South, where many small-scale fisheries are likely to expand as they gain access to larger markets. Using Chile as a case study, we assess brachyuran crab fisheries and provide a forward-looking view on the sustainability challenges of possible increases in demand by bringing together data on supply, demand, management, and, literature review. Dominated by two species (Metacarcinus edwarsii and Cancer porteri), production has centered in southern Chile and has fluctuated over the past decade, with landings declining since 2018. Between 20% and 30% of crab caught is exported, mostly to the United States and Belgium. In Belgium Chile is the third largest supplier. Few management regulations and monitoring programs exist. Limited spatio-temporal stock assessments, suggests the status of the dominant crab species may be jeopardized. Apart from ecology, the state of knowledge is limited across socio-economic, market, and fisheries management dimensions. There are initiatives to improve with an established Fisheries Improvement Project (FIP) in southern Chile. However, the lack of evidence of policy and management improvements has inactivated the FIP until the developed management plan proposal, based on an adaptive and precautionary approach (considering biological, ecological, economic, and social objectives) be approved by the government. This work reveals the importance of understanding the dynamics between supply and demand from holistic perspectives as well as the role of local efforts for resource sustainability in the context of increasing national and global crab demand. 

Abstract Earth's biosphere is undergoing drastic reorganization due to the sixth mass extinction brought on by the Anthropocene. Impacts of local and regional extirpation of species have been demonstrated to propagate through the complex interaction networks they are part of, leading to secondary extinctions and exacerbating biodiversity loss. Contemporary ecological theory has developed several measures to analyse the structure and robustness of ecological networks under biodiversity loss. However, a toolbox for directly simulating and quantifying extinction cascades and creating novel interactions (i.e. rewiring) remains absent.Here, we presentNetworkExtinction—a novel R package which we have developed to explore the propagation of species extinction sequences through ecological networks and quantify the effects of rewiring potential in response to primary species extinctions. WithNetworkExtinction, we integrate ecological theory and computational simulations to develop functionality with which users may analyse and visualize the structure and robustness of ecological networks. The core functions introduced withNetworkExtinctionfocus on simulations of sequential primary extinctions and associated secondary extinctions, allowing user‐specified secondary extinction thresholds and realization of rewiring potential.With the packageNetworkExtinction, users can estimate the robustness of ecological networks after performing species extinction routines based on several algorithms. Moreover, users can compare the number of simulated secondary extinctions against a null model of random extinctions. In‐built visualizations enable graphing topological indices calculated by the deletion sequence functions after each simulation step. Finally, the user can estimate the network's degree distribution by fitting different common distributions. Here, we illustrate the use of the package and its outputs by analysing a Chilean coastal marine food web.NetworkExtinctionis a compact and easy‐to‐use R package with which users can quantify changes in ecological network structure in response to different patterns of species loss, thresholds and rewiring potential. Therefore, this package is particularly useful for evaluating ecosystem responses to anthropogenic and environmental perturbations that produce nonrandom and sometimes targeted, species extinctions.