Marine reserve effects on fishery profit

Some studies suggest that fishery yields can be higher with reserves than under conventional management. However, the economic performance of fisheries depends on economic profit, not fish yield. The predictions of higher yields with reserves rely on intensive fishing pressures between reserves; the exorbitant costs of harvesting low-density populations erode profits. We incorporated this effect into a bioeconomic model to evaluate the economic performance of reserve-based management. Our results indicate that reserves can still benefit fisheries, even those targeting species that are expensive to harvest. However, in contrast to studies focused on yield, only a moderate proportion of the coast in reserves (with moderate harvest pressures outside reserves) is required to maximize profit. Furthermore, reserve area and harvest intensity can be traded off with little impact on profits, allowing for management flexibility while still providing higher profit than attainable under conventional management

Protracted recovery of long-spined urchin (Diadema antillarum) in the Bahamas

In 1983–1984, an unknown waterborne pathogen caused the mass mortality of long-spined sea urchin (Diadema antillarum) across the Caribbean and western tropical Atlantic. After approximately 15 years, urchin populations began to recover at some locations, yet few have reached pre-mortality densities. To date, no study has documented a recovery in the western tropical Atlantic outside of the Caribbean. Over a 25-year period (1991–2015), we documented an 8–17% population growth rate of D. antillarum in the central Bahamas. However, our mean observed densities, 0.06–0.38 urchins m −2, remained below pre-pandemic levels. Combined with observations from other locations in the Caribbean, it appears that D. antillarum populations are increasing, yet have not fully recovered from their 1980s mass mortality throughout much of their geographic range

Recruitment and the local dynamics of open marine populations

The majority of marine populations are demographically open; their replenishment is largely or exclusively dependent on a supply of juveniles from the plankton. In spite of much recent research, no consensus has yet been reached regarding the importance of recruitment relative to other demographic processes in determining local population densities. We argue 1. that demographic theory suggests that, except under restrictive and unlikely conditions, recruitment must influence local population density to some extent. Therefore, 2. the question as to whether the size of a particular population is limited by recruitment is misguided. Finally, 3. the effect of recruitment on population size can be difficult to detect but is nonetheless real. A major weakness of most existing studies is a lack of attention to the survival of recruits over appropriate scales of time and space. Acknowledgment of the multifactorial determination of population density should guide the design of future experimental studies of the demography of open populations

Reef fish ecology, conservaton, and fisheries: the scientific legacy of Glenn Almany

Despite his career being cut tragically short, Glenn Almany was a world leader in the ecology, conservation, and management of coral-reef fishes. Completing his BS at San Francisco State in 1996, he entered Mark Hixon's lab at Oregon State with an NSF pre-doctoral fellowship. He completed his PhD in 2002, publishing 6 papers in top journals. Glenn's novel field experiments showed that prior residents have strong effects on subsequent colonization of patch reefs. With lab mate Michael Webster, he also explored the intense early post-settlement mortality suffered by reef fishes. Glenn received a Fulbright Postdoctoral Fellowship in 2003 to study at James Cook Univ, where he began work with Geoff Jones and colleagues on larval connectivity. He was instrumental in developing and applying new methods to track larval dispersal in pelagic spawning fishes, publishing a seminal paper in Science in 2007. A second postdoctoral fellowship with the ARC Centre of Excellence for Coral Reef Studies enabled Glenn to apply these methods to determine the fate of larvae from grouper spawning aggregations in PNG, where he worked closely with remote local communities. He received a prestigious ARC Future Fellowship in 2010, and in the space of only 4 years published 20 papers, focusing predominantly on marine reserve design, connectivity and conservation of tropical fisheries resources. This period of his career was some of his most ambitious in scale, leading to substantial engagement in developing regional management programs in support of local fisheries within PNG and the Solomons