Edward V. Camp

Collapse of a historic oyster fishery: diagnosing causes and identifying paths toward increased resilience

Diagnosing causal factors of change at the ecosystem level is challenging because multiple drivers often interact at various spatial and temporal scales. We employ an integrated natural and social science approach to assess potential mechanisms leading to the collapse of an estuarine social-ecological system, and recommend future paths to increased system resilience. Our case study is the collapse of the eastern oyster (Crassostrea virginica) fishery in Apalachicola Bay, Florida, USA, and the associated impacts on local resource dependent communities. The oyster fishery collapse is the most recent in a series of environmental stressors to this region, which have included hurricanes and tropical storms, drought, and the Deepwater Horizon oil spill. We found it likely that the oyster collapse was not related to contamination from the recent oil spill, but rather to factors affecting oyster recruitment and survival, which may have been mediated by both human, e.g., fishing-related habitat alteration, and environmental, e.g., increased natural mortality from predators and disease, factors. The relative impact of each of these factors is likely to increase in the future because of changing climate and increased demand for fishery, water, and petroleum resources. Successful restoration and persistence of a viable oyster fishery will depend on: (1) implementation of some minimal best management practices, e.g., extensive habitat restoration via shell addition, and some spatial closures to harvest, (2) improving environmental knowledge and promoting episodic learning through enhanced monitoring and experimental management, and (3) continued community engagement necessary to produce adaptable governance suitable to responding to future unexpected challenges.

Potentials and Limitations of Stock Enhancement in Marine Recreational Fisheries Systems: An Integrative Review of Florida's Red Drum Enhancement

In this study, an integrative review of the potential for stock enhancement is conducted to support desirable management outcomes in marine recreational fisheries, focusing on the Florida, USA, red drum fishery as a case study. Here, stock enhancement is implicitly seen as a way of simultaneously achieving both ecological objectives of sustained wild fish populations and socioeconomic objectives of high fishing effort and/or catch rates. However, the review suggests that a fundamental tradeoff remains between these objectives in the short-term because stocking of hatchery fish is likely to result in at least partial displacement of wild fish through biological interactions as well as increased fishing pressure. Contrary to the perception of enhancement as a “quick fix,” successful use of the approach in the marine recreational fishery is likely to require sophisticated stock management and some adaptation in governance. In developing the enhancement, it will be necessary to address uncertainty in key attributes, specifically dynamics of recruitment, angler-effort responses, and stakeholder involvement. This may be achieved by combining quantitative modeling, monitoring, and stocking experiments in an active adaptive management framework to consider enhancement in the context of alternative management strategies. It is suggested that any interim enhancement should minimize ecological risk per socioeconomic benefit by stocking larger fish in areas where high fishing mortality limits abundance of wild fish. These conclusions are largely generalizable to other recreational enhancements, and this work serves as a model of rarely published a priori enhancement evaluation.

Understanding and Managing Social–Ecological Feedbacks in Spatially Structured Recreational Fisheries: The Overlooked Behavioral Dimension

Recreational fisheries are empirically tractable examples of social–ecological systems (SESs) that are characterized by complex interactions and feedbacks ranging from local to regional scales. The feedbacks among the three key compartments of the recreational fisheries SES—individual fish and populations, regionally mobile anglers, and regional and state-level fisheries managers—are strongly driven by behavior, but they are poorly understood. We review and identify factors, antecedents to behaviors, and behaviors most important to the outcomes of the coupled SES of recreational fisheries, which emerge from a range of social–ecological interactions. Using this information, we identify data gaps, suggest how to reduce uncertainty, and improve management advice for recreational fisheries focusing on open-access situations in inland fisheries. We argue that the seemingly micro-scale and local feedbacks between individual fish, fish populations, anglers, and managers lead to the emergence of important macro-s...

The curious case of eastern oyster Crassostrea virginica stock status in Apalachicola Bay, Florida

The Apalachicola Bay, Florida, eastern oyster (Crassostrea virginica) industry has annually produced about 10% of the U.S. oyster harvest. Today’s simple individual-operator, hand-tonging, small-vessel fishery is remarkably similar to the one that began in the 1800s. Unprecedented attention is currently being given to the status of oyster resources in Apalachicola Bay because this fishery has become central to the decision making related to multistate water disputes in the southeastern United States, as well as millions of dollars in funding for restoration programs related to the Deepwater Horizon oil spill. The oyster fishery collapsed in 2012, leading to large economic losses and community concerns over the current and future status of oyster resources, ecosystem health, and local economic opportunities. We used best available data to assess what mechanism(s) may have led to the collapse of the Apalachicola Bay oyster fishery. We then assessed the efficacy of alternative management strategies (e.g., restoration, fishery closure) to accelerate oyster population recovery. Our results suggest that the Apalachicola Bay oyster population is not overfished in the sense that recruitment has been limited by harvest, but that the 2012 collapse was driven by lower-than-average numbers and/or poor survival of juvenile oysters in the years preceding the collapse. This reduction in recruitment not only reduced the biomass of oysters available to harvest, but from a population resilience perspective, likely reduced the amount of dead shell material available as larval settlement area. Although the Apalachicola Bay oyster fishery has proven resilient over its >150-year history to periods of instability, this fishery now seems to be at a crossroads in terms of continued existence and possibly risks an irreversible collapse. How to use the restoration funds available, and which restoration and management practices to follow, are choices that will determine the long-term viability of the Apalachicola Bay oyster fishery.

Replacement of rooted macrophytes by filamentous macroalgae: effects on small fishes and macroinvertebrates

In aquatic environments around the globe, rooted macrophytes have been replaced by filamentous macroalgae. The consequences of such shifts in vegetative habitat for fauna are poorly understood. Given differences in morphology and life history characteristics of rooted macrophytes and filamentous macroalgae, we hypothesized that these habitat types were not functionally redundant for small-bodied fishes and macroinvertebrates. We examined this hypothesis in spring-fed Florida rivers characterized by decreases in native rooted macrophytes and concomitant increases in filamentous macroalgae. Although faunal densities were generally greater in filamentous macroalgae than in rooted macrophytes, differences in the community assemblage structure suggest that the two types of vegetative habitat do not function interchangeably. Accordingly, continued replacement of rooted macrophytes with filamentous macroalgae is expected to affect the small fish and macroinvertebrate community, as well as higher trophic levels that depend on it.

Use of Recovery Probabilities Can Improve Sampling Efficiency for Throw Traps in Vegetated Habitats

Abstract Throw traps are commonly used to assess small fish and macroinvertebrate (SFI) communities in aquatic habitats. Traditionally, numerous passes with a bar seine are used to remove all SFIs from within the throw trap, providing density estimates that are comparable across habitat types. However, similar information can be gathered with fewer seine passes than are traditionally used, thus allowing more sampling in a given field effort. The appropriate number of seine passes to meet study objectives can be determined if habitat-specific recovery probabilities are estimated. We investigated how SFI recovery probabilities within throw traps varied among five submerged aquatic vegetation habitat types and how these recovery probabilities can be used to determine the number of seine passes necessary to assess and detect differences in SFI relative abundance. Using a 1-m2 throw trap and bar seine, we found that estimates of SFI recovery probability were high (75–80%) and similar across habitats. Because o...

Grand Challenges in the Management and Conservation of North American Inland Fishes and Fisheries

Even with long-standing management and extensive science support, North American inland fish and fisheries still face many conservation and management challenges. We used a grand challenges approach to identify critical roadblocks that if removed would help solve important problems in the management and long-term conservation of North American inland fish and fisheries. We identified seven grand challenges within three themes (valuation, governance, and externalities) and 34 research needs and management actions. The major themes identified are to (1) raise awareness of diverse values associated with inland fish and fisheries, (2) govern inland fish and fisheries to satisfy multiple use and conservation objectives, and (3) ensure productive inland fisheries given nonfishing sector externalities. Addressing these grand challenges will help the broader community understand the diverse values of inland fish and fisheries, promote open forums for engagement of diverse stakeholders in fisheries management, and...