Host genetic identity determines parasite community structure across time and space in oyster restoration.

Intraspecific variation in host susceptibility to individual parasite species is common, yet how these effects scale to mediate the structure of diverse parasite communities in nature is less well understood. To address this knowledge gap, we tested how host genetic identity affects parasite communities on restored reefs seeded with juvenile oysters from different sources-a regional commercial hatchery or one of two wild progenitor lines. We assessed prevalence and intensity of three micro- and two macroparasite species for 4 years following restoration. Despite the spatial proximity of restored reefs, oyster source identity strongly predicted parasite community prevalence across all years, with sources varying in their relative susceptibility to different parasites. Oyster seed source also predicted reef-level parasite intensities across space and through time. Our results highlight that host intraspecific variation can shape parasite community structure in natural systems, and reinforce the importance of considering source identity and diversity in restoration design.

An assessment of marine, estuarine, and riverine habitat vulnerability to climate change in the Northeast U.S.

Climate change is impacting the function and distribution of habitats used by marine, coastal, and diadromous species. These impacts often exacerbate the anthropogenic stressors that habitats face, particularly in the coastal environment. We conducted a climate vulnerability assessment of 52 marine, estuarine, and riverine habitats in the Northeast U.S. to develop an ecosystem-scale understanding of the impact of climate change on these habitats. The trait-based assessment considers the overall vulnerability of a habitat to climate change to be a function of two main components, sensitivity and exposure, and relies on a process of expert elicitation. The climate vulnerability ranks ranged from low to very high, with living habitats identified as the most vulnerable. Over half of the habitats examined in this study are expected to be impacted negatively by climate change, while four habitats are expected to have positive effects. Coastal habitats were also identified as highly vulnerable, in part due to the influence of non-climate anthropogenic stressors. The results of this assessment provide regional managers and scientists with a tool to inform habitat conservation, restoration, and research priorities, fisheries and protected species management, and coastal and ocean planning.

Effects of a non-native cyanobacterium on bay scallops (Argopecten irradians) in a New England seagrass ecosystem.

Bay scallops (Argopecten irradians) are an economically valuable species whose populations have declined in recent decades due in part to harmful algal and cyanobacterial blooms. Nantucket, Massachusetts hosts one of the last remaining bay scallop fisheries in the U.S., but recently documented the occurrence of a non-native cyanobacterium (Hydrocoleum sp.). Hydrocoleum can form dense mats in seagrass beds, the primary habitat of scallops, but is also diazotrophic, potentially augmenting bioavailable nitrogen to primary producers and fueling secondary production. We conducted surveys to explore the relationships between Hydrocoleum and scallop condition, reproductive potential, and density in eelgrass beds in Nantucket Harbor as well as effects of other habitat characteristics (e.g., eelgrass cover) on these same scallop traits. We found low Hydrocoleum cover during our sampling, but found fewer large scallops in plots with Hydrocoleum, suggesting that this size class may be especially vulnerable to negative effects of Hydrocoleum. Contrary to expectation, we found a positive correlation between Hydrocoleum cover and scallop condition. These patterns suggest that Hydrocoleum may enhance scallop condition, but also affect habitat use, highlighting the need for manipulative experiments to clarify mechanisms driving these relationships. Understanding how non-native species such as Hydrocoleum impact fishery species will help advance conservation and resource management efforts.

Recruitment enhancement varies by taxonomic group and oyster reef habitat characteristics.

The rapid loss of coastal and estuarine biogenic habitats has reduced the delivery of valuable ecosystem services, resulting in calls for increased habitat restoration. Yet, a lack of information on how key habitat characteristics (e.g., area, vertical relief, age) influence the ability of restored habitats to deliver these ecosystem services hinders efforts to maximize the return on restoration investments. We conducted a meta-analysis to assess the influence of reef type (natural or restored), taxa, and restored reef size, vertical relief, age, and tidal zone on the presence and magnitude of recruitment enhancement for nekton (i.e., fish and swimming crabs). Both intertidal and subtidal reefs, as well as restored and natural reefs, enhanced nekton recruitment, though there was variation among taxonomic groups with reef types. Recruitment enhancement was more common across taxa on restored (six families) than on natural (one family) reefs. Resident nekton families were more consistently enhanced than transient families. Nekton enhancement varied with a number of restored reef characteristics. Recruitment enhancement increased with greater reef size across taxa, decreased with higher vertical relief for two families, showed maximum recruitment around a single intertidal reef age for one family, and showed minimum recruitment around a single subtidal reef age for three families. Understanding variation across species in response to key design elements will improve restoration success and enhance return on investment. Moving forward, we recommend studies that vary reef habitat characteristics independently and in combination to identify how variation in these characteristics interact to influence nekton recruitment enhancement by oyster reefs.

The diversity bonus in pooling local knowledge about complex problems.

Recently, theoreticians have hypothesized that diverse groups, as opposed to groups that are homogeneous, may have relative merits [S. E. Page, The Diversity Bonus (2019)]-all of which lead to more success in solving complex problems. As such, understanding complex, intertwined environmental and social issues may benefit from the integration of diverse types of local expertise. However, efforts to support this hypothesis have been frequently made through laboratory-based or computational experiments, and it is unclear whether these discoveries generalize to real-world complexities. To bridge this divide, we combine an Internet-based knowledge elicitation technique with theoretical principles of collective intelligence to design an experiment with local stakeholders. Using a case of striped bass fisheries in Massachusetts, we pool the local knowledge of resource stakeholders represented by graphical cognitive maps to produce a causal model of complex social-ecological interdependencies associated with fisheries ecosystems. Blinded reviews from a scientific expert panel revealed that the models of diverse groups outranked those from homogeneous groups. Evaluation via stochastic network analysis also indicated that a diverse group more adequately modeled complex feedbacks and interdependencies than homogeneous groups. We then used our data to run Monte Carlo experiments wherein the distributions of stakeholder-driven cognitive maps were randomly reproduced and virtual groups were generated. Random experiments also predicted that knowledge diversity improves group success, which was measured by benchmarking group models against an ecosystem-based fishery management model. We also highlight that diversity must be moderated through a proper aggregation process, leading to more complex yet parsimonious models.

Social Factors Key to Landscape-Scale Coastal Restoration: Lessons Learned from Three U.S. Case Studies.

In the United States, extensive investments have been made to restore the ecological function and services of coastal marine habitats. Despite a growing body of science supporting coastal restoration, few studies have addressed the suite of societally enabling conditions that helped facilitate successful restoration and recovery efforts that occurred at meaningful ecological (i.e., ecosystem) scales, and where restoration efforts were sustained for longer (i.e., several years to decades) periods. Here, we examined three case studies involving large-scale and long-term restoration efforts including the seagrass restoration effort in Tampa Bay, Florida, the oyster restoration effort in the Chesapeake Bay in Maryland and Virginia, and the tidal marsh restoration effort in San Francisco Bay, California. The ecological systems and the specifics of the ecological restoration were not the focus of our study. Rather, we focused on the underlying social and political contexts of each case study and found common themes of the factors of restoration which appear to be important for maintaining support for large-scale restoration efforts. Four critical elements for sustaining public and/or political support for large-scale restoration include: (1) resources should be invested in building public support prior to significant investments into ecological restoration; (2) building political support provides a level of significance to the recovery planning efforts and creates motivation to set and achieve meaningful recovery goals; (3) recovery plans need to be science-based with clear, measurable goals that resonate with the public; and (4) the accountability of progress toward reaching goals needs to be communicated frequently and in a way that the general public comprehends. These conclusions may help other communities move away from repetitive, single, and seemingly unconnected restoration projects towards more large-scale, bigger impact, and coordinated restoration efforts.

Views from the dock: Warming waters, adaptation, and the future of Maine's lobster fishery.

The ability of resource-dependent communities to adapt to climate change depends in part on their perceptions and prioritization of specific climate-related threats. In the Maine lobster fishery, which is highly vulnerable to warming water associated with climate change, we found a strong majority (84%) of fishers viewed warming water as a threat, but rank its impacts lower than other drivers of change (e.g., pollution). Two-thirds believed they will be personally affected by warming waters, but only half had plans to adapt. Those with adaptation plans demonstrated fundamentally different views of human agency in this system, observing greater anthropogenic threats, but also a greater ability to control the fishery through their own actions on the water and fisheries management processes. Lack of adaptation planning was linked to the view that warming waters result from natural cycles, and the expectation that technological advancements will help buffer the industry from warming waters.

Regional environmental variation and local species interactions influence biogeographic structure on oyster reefs.

Although species interactions are often assumed to be strongest at small spatial scales, they can interact with regional environmental factors to modify food web dynamics across biogeographic scales. The eastern oyster (Crassostrea virginica) is a widespread foundational species of both ecological and economic importance. The oyster and its associated assemblage of fish and macroinvertebrates is an ideal system to investigate how regional differences in environmental variables influence trophic interactions and food web structure. We quantified multiple environmental factors, oyster reef properties, associated species, and trophic guilds on intertidal oyster reefs within 10 estuaries along 900 km of the southeastern United States. Geographical gradients in fall water temperature and mean water depth likely influenced regional (i.e., the northern, central and southern sections of the SAB) variation in oyster reef food web structure. Variation in the biomass of mud crabs, an intermediate predator, was mostly (84.1%) explained by reefs within each site, and did not differ substantially among regions; however, regional variation in the biomass of top predators and of juvenile oysters also contributed to biogeographic variation in food web structure. In particular, region explained almost half (40.2%) of the variation in biomass of predators of blue crab, a top predator that was prevalent only in the central region where water depth was greater. Field experiments revealed that oyster mortality due to predation was greatest in the central region, suggesting spatial variation in the importance of trophic cascades. However, high oyster recruitment in the middle region probably compensates for this enhanced predation, potentially explaining why relatively less variation (17.9%) in oyster cluster biomass was explained by region. Region also explained over half of the variation in biomass of mud crab predators (55.2%), with the southern region containing almost an order of magnitude more biomass than the other two regions. In this region, higher water temperatures in the fall corresponded with higher biomass of fish that consume mud crabs and of fish that consume juvenile and forage fish, whereas biomas of their prey (mud crabs and juvenile and forage fish, respectively) was generally low in the southern region. Collectively, these results show how environmental gradients interact with trophic cascades to structure food webs associated with foundation species across biogeographic regions.

Chronic social disruption following a systemic fishery failure.

In the United States, the iconic groundfish fishery for Gulf of Maine cod has endured several dramatic reductions in annual catch limits and been federally declared an economic disaster. Using a repeated cross-sectional survey of fishing captains to assess potential social impacts of the fishery failure, we found that psychological distress and social disruption were pervasive throughout New England fishing communities. For instance, our results indicate that 62% of captains self-reported severe or moderate psychological distress 1 y after the crisis began, and these patterns have persisted for 5 y. Using classification tree analyses, we found that low levels of trust in fisheries management was the most powerful predictor of both initial and chronic psychological distress. Distress was most severe among individuals without income diversity and those with dependents in the household. Compared to other aspects of fisheries, measuring and managing for noneconomic social outcomes and human well-being has lagged behind, even though it is a necessary component of mitigating the adverse impacts of fisheries disruptions.

Genetic diversity and phenotypic variation within hatchery-produced oyster cohorts predict size and success in the field.

The rapid growth of the aquaculture industry to meet global seafood demand offers both risks and opportunities for resource management and conservation. In particular, hatcheries hold promise for stock enhancement and restoration, yet cultivation practices may lead to enhanced variation between populations at the expense of variation within populations, with uncertain implications for performance and resilience. To date, few studies have assessed how production techniques impact genetic diversity and population structure, as well as resultant trait variation in and performance of cultivated offspring. We collaborated with a commercial hatchery to produce multiple cohorts of the eastern oyster (Crassostrea virginica) from field-collected broodstock using standard practices. We recorded key characteristics of the broodstock (male : female ratio, effective population size), quantified the genetic diversity of the resulting cohorts, and tested their trait variation and performance across multiple field sites and experimental conditions. Oyster cohorts produced under the same conditions in a single hatchery varied almost twofold in genetic diversity. In addition, cohort genetic diversity was a significant positive predictor of oyster performance traits, including initial size and survival in the field. Oyster cohorts produced in the hatchery had lower within-cohort genetic variation and higher among-cohort genetic structure than adults surveyed from the same source sites. These findings are consistent with "sweepstakes reproduction" in oysters, even when manually spawned. A readily measured characteristic of broodstock, the ratio of males to females, was positively correlated with within-cohort genetic diversity of the resulting offspring. Thus, this metric may offer a tractable way both to meet short-term production goals for seafood demand and to ensure the capacity of hatchery-produced stock to achieve conservation objectives, such as the recovery of self-sustaining wild populations.

Voluntary Restoration: Mitigation's Silent Partner in the Quest to Reverse Coastal Wetland Loss in the USA.

Coastal ecosystems are under pressure from a vast array of anthropogenic stressors, including development and climate change, resulting in significant habitat losses globally Conservation policies are often implemented with the intent of reducing habitat loss. However, losses already incurred will require restoration if ecosystem functions and services are to be recovered. The United States has a long history of wetland loss and recognizes that averting loss requires a multi-pronged approach including mitigation for regulated activities and non-mitigation (voluntary herein) restoration. The 1989 "No Net Loss" (NNL) policy stated the Federal government's intent that losses of wetlands would be offset by at least as many gains of wetlands. However, coastal wetlands losses result from both regulated and non-regulated activities. We examined the effectiveness of Federally funded, voluntary restoration efforts in helping avert losses of coastal wetlands by assessing: (1) What are the current and past trends in coastal wetland change in the U.S.?; and (2) How much and where are voluntary restoration efforts occurring? First, we calculated palustrine and estuarine wetland change in U.S. coastal shoreline counties using data from NOAA's Coastal Change Analysis Program, which integrates both types of potential losses and gains. We then synthesized available data on Federally funded, voluntary restoration of coastal wetlands. We found that from 1996 to 2010, the U.S. lost 139,552 acres (~565 km2) of estuarine wetlands (2.5% of 1996 area) and 336,922 acres (~1,363 km2) of palustrine wetlands (1.4%). From 2006 to 2015, restoration of 145,442 acres (~589 km2) of estuarine wetlands and 154,772 acres (~626 km2) of palustrine wetlands occurred. Further, wetland losses and restoration were not always geographically aligned, resulting in local and regional "winners" and "losers." While these restoration efforts have been considerable, restoration and mitigation collectively have not been able to keep pace with wetland losses; thus, reversing this trend will likely require greater investment in coastal habitat conservation and restoration efforts. We further conclude that "area restored," the most prevalent metric used to assess progress, is inadequate, as it does not necessarily equate to restoration of functions. Assessing the effectiveness of wetland restoration not just in the U.S., but globally, will require allocation of sufficient funding for long-term monitoring of restored wetland functions, as well as implementation of standardized methods for monitoring data collection, synthesis, interpretation, and application.

Competitive and agonistic interactions between the invasive Asian shore crab and juvenile American lobster.

Invasive species can have profound ecological and evolutionary impacts on native fauna, particularly those from overlapping guilds. Intraguild predation and competition often occur simultaneously, and ontogenetic shifts in competitive strength can dictate the magnitude and direction of species interactions. The recent introduction of the Asian shore crab Hemigrapsus sanguineus to the Atlantic coast of North America has resulted in the potential for considerable intraguild interactions with juvenile American lobsters Homarus americanus, with which it now co-occupies rocky intertidal and shallow subtidal habitats. We present data from 5 yr of monthly (May-October) field sampling revealing a significant decline in lobster density as H. sanguineus density increased in the low intertidal. To investigate potential mechanisms behind this pattern, we conducted three mesocosm experiments designed to examine whether competitive interactions between H. americanus and H. sanguineus are size- or density-dependent. Larger early benthic phase lobsters (16-34 mm CL) outcompeted H. sanguineus for both food and shelter resources. These lobsters fed faster and more in the presence of H. sanguineus, effectively defended shelter, were responsible for the majority of agonistic interactions, and, in multiple instances, killed and consumed H. sanguineus. Effects on sheltering and agonstic interactions by these lobsters were independent of H. sanguineus density; however, prior shelter residency increased lobster agonistic behavior towards crabs. In contrast, H. sanguineus outcompeted smaller, early benthic phase lobsters (7.2-11.2 mm CL) for shelter, and these interactions were density dependent. Displacement of lobsters from shelter by crabs and cumulative agonistic interactions instigated by crabs towards lobsters scaled positively with H. sanguineus density. Given the similarity of the invasion documented here and others occurring globally, these experiments demonstrate the importance of considering how factors such as ontogeny, density-dependence, and primacy influence the outcomes of interactions between intraguild predators. Disentangling how these factors structure intraguild interactions between invasive and endemic species will both advance our fundamental understanding of community ecology and enhance efforts to conserve and manage natural resources.

Oyster reefs as carbon sources and sinks.

Carbon burial is increasingly valued as a service provided by threatened vegetated coastal habitats. Similarly, shellfish reefs contain significant pools of carbon and are globally endangered, yet considerable uncertainty remains regarding shellfish reefs' role as sources (+) or sinks (-) of atmospheric CO2 While CO2 release is a by-product of carbonate shell production (then burial), shellfish also facilitate atmospheric-CO2 drawdown via filtration and rapid biodeposition of carbon-fixing primary producers. We provide a framework to account for the dual burial of inorganic and organic carbon, and demonstrate that decade-old experimental reefs on intertidal sandflats were net sources of CO2 (7.1 ± 1.2 MgC ha-1 yr-1 (µ ± s.e.)) resulting from predominantly carbonate deposition, whereas shallow subtidal reefs (-1.0 ± 0.4 MgC ha-1 yr-1) and saltmarsh-fringing reefs (-1.3 ± 0.4 MgC ha-1 yr-1) were dominated by organic-carbon-rich sediments and functioned as net carbon sinks (on par with vegetated coastal habitats). These landscape-level differences reflect gradients in shellfish growth, survivorship and shell bioerosion. Notably, down-core carbon concentrations in 100- to 4000-year-old reefs mirrored experimental-reef data, suggesting our results are relevant over centennial to millennial scales, although we note that these natural reefs appeared to function as slight carbon sources (0.5 ± 0.3 MgC ha-1 yr-1). Globally, the historical mining of the top metre of shellfish reefs may have reintroduced more than 400 000 000 Mg of organic carbon into estuaries. Importantly, reef formation and destruction do not have reciprocal, counterbalancing impacts on atmospheric CO2 since excavated organic material may be remineralized while shell may experience continued preservation through reburial. Thus, protection of existing reefs could be considered as one component of climate mitigation programmes focused on the coastal zone.

Genetic by environmental variation but no local adaptation in oysters (Crassostrea virginica).

Functional trait variation within and across populations can strongly influence population, community, and ecosystem processes, but the relative contributions of genetic vs. environmental factors to this variation are often not clear, potentially complicating conservation and restoration efforts. For example, local adaptation, a particular type of genetic by environmental (G*E) interaction in which the fitness of a population in its own habitat is greater than in other habitats, is often invoked in management practices, even in the absence of supporting evidence. Despite increasing attention to the potential for G*E interactions, few studies have tested multiple populations and environments simultaneously, limiting our understanding of the spatial consistency in patterns of adaptive genetic variation. In addition, few studies explicitly differentiate adaptation in response to predation from other biological and environmental factors. We conducted a reciprocal transplant experiment of first-generation eastern oyster (Crassostrea virginica) juveniles from six populations across three field sites spanning 1000 km in the southeastern Atlantic Bight in both the presence and absence of predation to test for G*E variation in this economically valuable and ecologically important species. We documented significant G*E variation in survival and growth, yet there was no evidence for local adaptation. Condition varied across oyster cohorts: Offspring of northern populations had better condition than offspring from the center of our region. Oyster populations in the southeastern Atlantic Bight differ in juvenile survival, growth, and condition, yet offspring from local broodstock do not have higher survival or growth than those from farther away. In the absence of population-specific performance information, oyster restoration and aquaculture may benefit from incorporating multiple populations into their practices.

Nonconsumptive effects of a predator weaken then rebound over time.

Predators can influence prey traits and behavior (nonconsumptive effects [NCEs]), often with cascading effects for basal resources and ecosystem function. But critiques of NCE experiments suggest that their duration and design produce results that describe the potential importance of NCEs rather than their actual importance. In light of these critiques, we re-evaluated a toadfish (predator), crab (prey), and oyster (resource) NCE-mediated trophic cascade. In a 4-month field experiment, we varied toadfish cue (NCE) and crab density (approximating variation in predator consumptive effects, CE). Toadfish initially benefitted oyster survival by causing crabs to reduce consumption. But this NCE weakened over time (possibly due to prey hunger), so that after 2 months, crab density (CE) dictated oyster survivorship, regardless of cue. However, the NCE ultimately re-emerged on reefs with a toadfish cue, increasing oyster survivorship. At no point did the effect of toadfish cue on mud crab foraging behavior alter oyster population growth or sediment organic matter on the reef, which is a measure of benthic-pelagic coupling. Instead, both decreased with increasing crab density. Thus, within a system shown to exhibit strong NCEs in short-term experiments (days) our study supported predictions from theoretical models: (a) within the generation of individual prey, the relative influence of NCEs appears to cycle over longer time periods (months); and (b) predator CEs, not NCEs, drive longer-term resource dynamics and ecosystem function. Thus, our study implies that the impacts of removing top predators via activities such as hunting and overfishing will cascade to basal resources and ecosystem properties primarily through density-mediated interactions.

Predators, environment and host characteristics influence the probability of infection by an invasive castrating parasite.

Not all hosts, communities or environments are equally hospitable for parasites. Direct and indirect interactions between parasites and their predators, competitors and the environment can influence variability in host exposure, susceptibility and subsequent infection, and these influences may vary across spatial scales. To determine the relative influences of abiotic, biotic and host characteristics on probability of infection across both local and estuary scales, we surveyed the oyster reef-dwelling mud crab Eurypanopeus depressus and its parasite Loxothylacus panopaei, an invasive castrating rhizocephalan, in a hierarchical design across >900 km of the southeastern USA. We quantified the density of hosts, predators of the parasite and host, the host's oyster reef habitat, and environmental variables that might affect the parasite either directly or indirectly on oyster reefs within 10 estuaries throughout this biogeographic range. Our analyses revealed that both between and within estuary-scale variation and host characteristics influenced L. panopaei prevalence. Several additional biotic and abiotic factors were positive predictors of infection, including predator abundance and the depth of water inundation over reefs at high tide. We demonstrate that in addition to host characteristics, biotic and abiotic community-level variables both serve as large-scale indicators of parasite dynamics.

Refuge quality impacts the strength of nonconsumptive effects on prey.

Prey often retreat into the safety of refuges for protection from predators. This shift into refuge can reduce foraging opportunities, escalating the costs of risk and the strength of nonconsumptive effects. Such costs, however, may be shaped by the variation in resources that refuges harbor for prey foraging (i.e., refuge quality), and change dynamically via impacts on prey state. Despite its potential importance, we lack an explicit understanding of how refuge quality impacts prey performance under risk. Using a rocky intertidal food chain, we examined the interaction between predation risk and the amount of resources available for prey in refuge. We found that refuges with more resources greatly reduce the costs of refuge use, and that nonconsumptive effects are thereby weakened by as much as one-half, with especially strong impacts on prey growth and growth efficiency. These results suggest that failure to consider refuge quality could result in overestimation of the negative effects associated with prey refuge use.

Ecological Consequences of Shoreline Hardening: A Meta-Analysis.

Protecting coastal communities has become increasingly important as their populations grow, resulting in increased demand for engineered shore protection and hardening of over 50% of many urban shorelines. Shoreline hardening is recognized to reduce ecosystem services that coastal populations rely on, but the amount of hardened coastline continues to grow in many ecologically important coastal regions. Therefore, to inform future management decisions, we conducted a meta-analysis of studies comparing the ecosystem services of biodiversity (richness or diversity) and habitat provisioning (organism abundance) along shorelines with versus without engineered-shore structures. Seawalls supported 23% lower biodiversity and 45% fewer organisms than natural shorelines. In contrast, biodiversity and abundance supported by riprap or breakwater shorelines were not different from natural shorelines; however, effect sizes were highly heterogeneous across organism groups and studies. As coastal development increases, the type and location of shoreline hardening could greatly affect the habitat value and functioning of nearshore ecosystems.

Maximizing oyster-reef growth supports green infrastructure with accelerating sea-level rise.

Within intertidal communities, aerial exposure (emergence during the tidal cycle) generates strong vertical zonation patterns with distinct growth boundaries regulated by physiological and external stressors. Forecasted accelerations in sea-level rise (SLR) will shift the position of these critical boundaries in ways we cannot yet fully predict, but landward migration will be impaired by coastal development, amplifying the importance of foundation species' ability to maintain their position relative to rising sea levels via vertical growth. Here we show the effects of emergence on vertical oyster-reef growth by determining the conditions at which intertidal reefs thrive and the sharp boundaries where reefs fail, which shift with changes in sea level. We found that oyster reef growth is unimodal relative to emergence, with greatest growth rates occurring between 20-40% exposure, and zero-growth boundaries at 10% and 55% exposures. Notably, along the lower growth boundary (10%), increased rates of SLR would outpace reef accretion, thereby reducing the depth range of substrate suitable for reef maintenance and formation, and exacerbating habitat loss along developed shorelines. Our results identify where, within intertidal areas, constructed or natural oyster reefs will persist and function best as green infrastructure to enhance coastal resiliency under conditions of accelerating SLR.

Assessing Fishers' Support of Striped Bass Management Strategies.

Incorporating the perspectives and insights of stakeholders is an essential component of ecosystem-based fisheries management, such that policy strategies should account for the diverse interests of various groups of anglers to enhance their efficacy. Here we assessed fishing stakeholders' perceptions on the management of Atlantic striped bass (Morone saxatilis) and receptiveness to potential future regulations using an online survey of recreational and commercial fishers in Massachusetts and Connecticut (USA). Our results indicate that most fishers harbored adequate to positive perceptions of current striped bass management policies when asked to grade their state's management regime. Yet, subtle differences in perceptions existed between recreational and commercial fishers, as well as across individuals with differing levels of fishing experience, resource dependency, and tournament participation. Recreational fishers in both states were generally supportive or neutral towards potential management actions including slot limits (71%) and mandated circle hooks to reduce mortality of released fish (74%), but less supportive of reduced recreational bag limits (51%). Although commercial anglers were typically less supportive of management changes than their recreational counterparts, the majority were still supportive of slot limits (54%) and mandated use of circle hooks (56%). Our study suggests that both recreational and commercial fishers are generally supportive of additional management strategies aimed at sustaining healthy striped bass populations and agree on a variety of strategies. However, both stakeholder groups were less supportive of harvest reductions, which is the most direct measure of reducing mortality available to fisheries managers. By revealing factors that influence stakeholders' support or willingness to comply with management strategies, studies such as ours can help managers identify potential stakeholder support for or conflicts that may result from regulation changes.