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ABSTRACT Spatial processes, particularly scale‐dependent feedbacks, may play important and underappreciated roles in the dynamics of bistable ecosystems. For example, self‐organised spatial patterns can allow for stable coexistence of alternative states outside regions of bistability, a phenomenon known as a Busse balloon. We used partial differential equations to explore the potential for such dynamics in coral reefs, focusing on how herbivore behaviour and mobility affect the stability of coral‐ and macroalgal‐dominated states. Herbivore attraction to coral resulted in a Busse balloon that enhanced macroalgal resilience, with patterns persisting in regions of parameter space where nonspatial models predict uniform coral dominance. Thus, our work suggests herbivore association with coral (e.g., for shelter) can prevent reefs from reaching a fully coral‐dominated state. More broadly, this study illustrates how consumer space use can prevent ecosystems from undergoing wholesale state transitions, highlighting the importance of explicitly accounting for space when studying bistable systems. 

Small-scale fisheries provide seafood for billions of people and are one of the largest employers in many coastal communities. Those households engaged in these fisheries who maintain diverse income sources are generally thought to be better prepared to cope with social or ecological perturbations such as the crises presented by the COVID-19 pandemic. One outcome of the COVID-19 crisis was the collapse of international tourism after many nations instituted strict border controls to slow the virus’s spread, severely impacting coastal communities that depend on tourism-related employment. This research assessed the effects of COVID-19-induced collapse of tourism on small-scale coral reef fishers and households in Moorea, French Polynesia. Ninety-five households were surveyed about their livelihoods, fishing, demographics, and income-generating occupations before and after the lockdown. Shifts in fish biomass were evaluated using time series data collected through underwater visual surveys, and roadside fish vendors were surveyed to assess fish sales. Results showed that after tourism employment evaporated more Moorea households began fishing to boost their incomes and food security. However, the increase in fishing pressure showed no appreciable decline in the biomass of fishable species. The households responsible for the increased fishing activities were those who were working in the tourism economy prior to the pandemic and subsequently lost their jobs. Households that combined fishing with construction or other stable sectors showed greater abilities to cope, while those combining fishing with tourism were heavily impacted. Importantly, results showed that those households devoted solely to fishing managed the crisis adeptly due to their superior fishing skills and ecological knowledge. This pattern suggests that not all forms of household livelihood diversification confer equal advantages and that resource-dependent households are not necessarily intrinsically less resilient. More generally, it is argued that we should be cautious when promoting livelihood diversification as a blanket solution to decrease household vulnerability, and that ecological knowledge diversity is underappreciated.