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Healthy parrotfish (family Scaridae) communities fulfill the essential ecosystem process of herbivory in coral reefs, but artisanal fisheries that target parrotfish have degraded their populations. Outright bans and gear restrictions that do not allow parrotfish capture can effectively protect and restore parrotfish populations. As these management actions would be unfeasible in many places, options that allow some fishing but still encourage population rebuilding need to be considered. The life history of parrotfish complicates management decisions because they transition from a mostly female “initial phase” to an all-male “terminal phase.” Size-selective fishing on the largest fish can lead to unnaturally low proportions of males in a population, potentially leading to losses in reproduction. At the same time, these visually distinct life phases could present an opportunity to employ a type of catch restriction that would be easy to understand and monitor. We built an agent-based model of the stoplight parrotfish, Sparisoma viride, which included three possible mechanisms of life-phase transitioning, to predict how this species and others like it might react to catch restrictions based on life phase. We found that restricting catch to only terminal-phase (male) fish typically led to populations of greater abundance and biomass and less-disturbed life-phase ratio, compared to a similar fishing mortality applied to the whole population. This model result highlights a potentially important lesson for all exploited protogynous hermaphrodites: a robust population of initial-phase fish may be key to maximizing reproductive potential when the size at life-phase transition compensates for changes in population structure.

Bahaman coral reefs have been on a steady decline since the 1900s, following the arrival of Europeans to the islands. Conditions have only worsened since, with the primary cause being overfishing. Overfishing depletes fish stocks and denies corals the interaction with functional groups that are necessary for their health. Without a strong herbivorous contingent of fish, reefs have slid into a macro algal trophic level that is difficult to reverse. This study focuses on the extent of overfishing of reef species by foreign boats in the Bahamas. It also considers contribution foreign boaters make to the local economy and their willingness to pay for conservation measures. With estimates of the amount of seafood recreational boaters and local commercial fishermen catch, a comparison is made about their relative contribution to the overfishing problem. A determination of boater’s spending provides an estimate of their contribution to the local economy. The willingness to pay for reef conservation and moorings indicates whether more money can be extracted for marine conservation projects. The study was conducted in the Exumas, a group of out islands southeast of Nassau that are representative of the reef degradation and development found throughout the Bahamas.

The exotic coral reefs of the Abrolhos Bank are a valuable source of goods and services for many Brazilians. The Abrolhos coral reefs are home to the most productive reef fisheries on the entire Brazilian coast and attract tourists each year with their natural beauty. Yet in the last fifty years, commercial fishing has replaced artisanal fishing, the Atlantic forest cover has vanished, and oil and gas exploration has begun. A network of marine protected areas (MPAs) is an achievable and effective solution to protect this coral reef ecosystem before the sustainability of the local fisheries and tourism industry are compromised. This study identifies gaps in knowledge about Abrolhos coral reef ecosystem and provides a much needed framework for the collection and analysis of data essential for MPA network design including identifying threats, understanding the factors that maintain coral reef resilience, determining methods for monitoring MPA success, and identifying obstacles to establishing MPAs.