Participatory Conservation of Coastal Habitats: The Importance of Understanding Homeowner Decision Making to Mitigate Cascading Shoreline Degradation

Along densely populated coasts, the armoring of shorelines is a prevalent cause of natural habitat loss and degradation. This article explores the values and decision making of waterfront homeowners and identifies two interlinked and potentially reversible drivers of coastal degradation. We discovered that: (1) misperceptions regarding the environmental impacts and cost-effectiveness of different shoreline conditions was common and may promote armoring; and (2) many homeowners reported only altering their shorelines in response to damage caused by armoring on neighboring properties. Collectively, these findings suggest that a single homeowner’s decision may trigger cascading degradation along a shoreline, which highlights the necessity of protecting existing large stretches of natural shoreline. However, our study also found that most homeowners were concerned with environmental impacts and preferred the aesthetics of natural landscapes, both of which could indicate nascent support and pathways for conservation initiatives along residential shorelines

Integrating Societal Perspectives and Values for Improved Stewardship of a Coastal Ecosystem Engineer

Oyster reefs provide coastal societies with a vast array of ecosystem services, but are also destructively harvested as an economically and culturally important fishery resource, exemplifying a complex social-ecological system (SES). Historically, societal demand for oysters has led to destructive and unsustainable levels of harvest, which coupled with multiple other stressors has placed oyster reefs among the most globally imperiled coastal habitats. However, more recent studies have demonstrated that large-scale restoration is possible and that healthy oyster populations can be sustained with effective governance and stewardship. However, both of these require significant societal support or financial investment. In our study, we explored relationships among how coastal societies (1) perceive and value oyster ecosystem services, (2) recognize and define problems associated with oyster decline, and (3) perceive or support stewardship initiatives. We specifically focused on the SES of eastern oysters (Crassostrea virginica) and coastal societies in the northern Gulf of Mexico, a region identified as offering among the last and best opportunities to sustainably balance conservation objectives with a wild fishery. We found that, in addition to harvest-related benefits, oysters were highly valued for providing habitat, mitigating shoreline erosion, and improving water quality or clarity. Our results also showed that although most respondents recognized that oyster populations have declined, many respondents characterized the problem differently than most scientific literature does. Among a variety of initiatives for enhancing sustainability, spawning sanctuaries and reef restoration were well supported in all states, but support for harvest reductions was less consistent. Our study suggests that public support for maintaining both harvest and ecosystem services exists at societal levels and that enhancing public awareness regarding the extent and causes of oyster decline could garner additional support for stewardship initiatives. Collectively, the societal, economic, and biophysical complexities of the northern Gulf of Mexico oyster SES illustrate the need and public support for developing more comprehensive management schemes for exploited ecosystem engineers

How much marsh restoration is enough to deliver wave attenuation coastal protection benefits?

© The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Castagno, K., Ganju, N., Beck, M., Bowden, A., & Scyphers, S. How much marsh restoration is enough to deliver wave attenuation coastal protection benefits? Frontiers in Marine Science, 8, (2022): 756670, https://doi.org/10.3389/fmars.2021.756670.As coastal communities grow more vulnerable to sea-level rise and increased storminess, communities have turned to nature-based solutions to bolster coastal resilience and protection. Marshes have significant wave attenuation properties and can play an important role in coastal protection for many communities. Many restoration projects seek to maximize this ecosystem service but how much marsh restoration is enough to deliver measurable coastal protection benefits is still unknown. This question is critical to guiding assessments of cost effectiveness and for funding, implementation, and optimizing of marsh restoration for risk reduction projects. This study uses SWAN model simulations to determine empirical relationships between wave attenuation and marsh vegetation. The model runs consider several different common marsh morphologies (including systems with channels, ponds, and fringing mudflats), vegetation placement, and simulated storm intensity. Up to a 95% reduction in wave energy is seen at as low as 50% vegetation cover. Although these empirical relationships between vegetative cover and wave attenuation provide essential insight for marsh restoration, it is also important to factor in lifespan estimates of restored marshes when making overall restoration decisions. The results of this study are important for coastal practitioners and managers seeking performance goals and metrics for marsh restoration, enhancement, and creation

Resistance, resilience, and recovery of salt marshes in the Florida Panhandle following Hurricane Michael.

Characterizing the fragility, resistance, and resilience of marshes is critical for understanding their role in reducing storm damages and for helping to manage the recovery of these natural defenses. This study uses high-resolution aerial imagery to quantify the impacts of Hurricane Michael, a category 5 hurricane, on coastal salt marshes in the Florida Panhandle, USA. Marsh damage was classified into several categories, including deposition of sediment or wrack, fallen trees, vegetation loss, and conversion to open water. The marshes were highly resistant to storm damages even under extreme conditions; only 2% of the 173,259 km2 of marshes in the study area were damaged-a failure rate much lower than that of artificial defenses. Marshes may be more resistant than resilient to storm impacts; damaged marshes were slow to recover, and only 16% of damaged marshes had recovered 6 months after landfall. Marsh management mattered for resistance and resilience; marshes on publicly-managed lands were less likely to be damaged and more likely to recover quickly from storm impacts than marshes on private land, emphasizing the need to incentivize marsh management on private lands. These results directly inform policy and practice for hazard mitigation, disaster recovery, adaptation, and conservation, particularly given the potential for more intense hurricane landfalls as the climate changes

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

Ecological impacts of non-native Pacific oysters (Crassostrea gigas) and management measures for protected areas in Europe

Pacific oysters are now one of the most ‘globalised’ marine invertebrates. They dominate bivalve aquaculture production in many regions and wild populations are increasingly becoming established, with potential to displace native species and modify habitats and ecosystems. While some fishing communities may benefit from wild populations, there is now a tension between the continued production of Pacific oysters and risk to biodiversity, which is of particular concern within protected sites. The issue of the Pacific oyster therefore locates at the intersection between two policy areas: one concerning the conservation of protected habitats, the other relating to livelihoods and the socio-economics of coastal aquaculture and fishing communities. To help provide an informed basis for management decisions, we first summarise evidence for ecological impacts of wild Pacific oysters in representative coastal habitats. At local scales, it is clear that establishment of Pacific oysters can significantly alter diversity, community structure and ecosystem processes, with effects varying among habitats and locations and with the density of oysters. Less evidence is available to evaluate regional-scale impacts. A range of management measures have been applied to mitigate negative impacts of wild Pacific oysters and we develop recommendations which are consistent with the scientific evidence and believe compatible with multiple interests. We conclude that all stakeholders must engage in regional decision making to help minimise negative environmental impacts, and promote sustainable industry development

Gulf-Wide Decreases in the Size of Large Coastal Sharks Documented by Generations of Fishermen

Large sharks are top predators in most coastal and marine ecosystems throughout the world, and evidence of their reduced prominence in marine ecosystems has been a serious concern for fisheries and ecosystem management. Unfortunately, quantitative data to document the extent, timing, and consequences of changes in shark populations are scarce, thwarting examination of long-term (decadal, century) trends, and reconstructions based on incomplete data sets have been the subject of debate. Absence of quantitative descriptors of past ecological conditions is a generic problem facing many fields of science but is particularly troublesome for fisheries scientists who must develop specific targets for restoration. We were able to use quantitative measurements of shark sizes collected annually and independently of any scientific survey by thousands of recreational fishermen over the last century to document decreases in the size of large sharks from the northern Gulf of Mexico. Based on records from fishing rodeos in three U.S. coastal states, the size (weight or length) of large sharks captured by fishermen decreased by 50–70% during the 20 years after the 1980s. The pattern is largely driven by reductions in the occurrence and sizes of Tiger Sharks Galeocerdo cuvier and Bull Sharks Carcharhinus leucas and to a lesser extent Hammerheads Sphyrna spp. This decrease occurred despite increasing fishing effort and advances in technology, but it is coincident with the capitalization of the U.S. commercial shark long-line fishery in the GOM

Co-Producing a Shared Characterization of Depredation in the Gulf of Mexico Reef Fish Fishery: Comprehensive Report

Depredation, defined as the partial or complete removal of a hooked fish by a non-target species, is a cryptic form of mortality that can affect the accuracy of stock assessments and species management efforts. Accounting for depredation is crucial to minimize uncertainty in stock assessment models and to obtain accurate and reliable fisheries catch data. If these interactions are frequent, failure to properly quantify this form of mortality can lead to the underestimation of reef fish population removals, inappropriate harvest recommendations, and stakeholder unrest. In recent years, depredation has escalated in the Gulf of Mexico (GoM) reef fish fishery. Although GoM reef fish fishery stakeholders (fishermen) have actively pushed for resource managers to implement solutions to address these increasingly pervasive interactions, a comprehensive characterization of this issue is lacking, and trends surrounding GoM reef fish depredation – as well as factors that impact depredation – have not been adequately described or evaluated. Therefore, the objective of this project was to co-produce a shared characterization of the impacts of depredation in the GoM reef fish fishery. To accomplish this, we employed a three-phased approach consisting of synthesis (phase 1), survey (phase 2), and feedback (phase 3). During phase 1, we synthesized data from the NOAA Fisheries Southeast Fisheries Science Center (SEFSC) GoM Reef Fish Observer Program, the largest and longest depredation-related dataset available. Marked increases in depredation were shown starting in 2017 for both bottom longline and vertical longline, particularly in the Eastern GoM. To complement the analysis of the commercial sector from phase 1, we designed and implemented an electronic survey of private recreational anglers in phase 2. Survey results demonstrate that anglers across the GoM routinely experience depredation and have identified a variety of influential factors such as geographic location and depth. Surprisingly, depredation has not affected fishing behavior for the majority of those surveyed. Findings from the commercial fishery (phase 1) and private recreational fishery (phase 2) were then presented to a representative group of (predominantly) charter-for-hire fishermen during an in-person, collaborative participatory modeling workshop (phase 3). These stakeholders provided unique insights, suggesting that factors like the length of the red snapper fishing season, recreational angler high-grading, and a diminished GoM shrimp trawl fleet, have led to increases in depredation. Perhaps more importantly, these stakeholders noted a growing disconnect between their on-the-water observations (i.e., increased depredation), and what they perceived as an increasing desire from NOAA Fisheries and the general public to protect all sharks. Notably, these sentiments resulted in a lack of trust with respect to shark science, stock assessments, and resource management. Ultimately, this planning project led to a deeper understanding of shark depredation in the GoM commercial, private recreational, and charter-for-hire fisheries. Project findings formed the basis of a comprehensive Research and Development Plan and an Application Plan. In addition, data and insights from this planning project contributed to a peer-reviewed depredation review (Mitchell et al. 2022), a stock assessment report (Drymon et al. 2022), a manuscript in prep (Duffin et al.), five conference presentations, and three outreach products.

Land reclamation and artificial islands: Walking the tightrope between development and conservation

Coastal developments worldwide have put entire shoreline ecosystems at risk. Recently, land reclamation has been extended to the construction of whole new islands; a phenomenon that is particularly common in Asia and the Middle East and is recognised as a global conservation issue. Using Penang Island, Malaysia as a case study, we illustrate the relationship between rapid population growth and the simultaneous increase in urbanisation, land reclamation and extent of artificial shorelines; and decrease in the quality and extent of natural coastal habitats. Our goal was to provide an up-to-date assessment of the state of coastal habitats around Penang, identify knowledge gaps and identify locations that may be potentially suitable for eco-engineering. Comparisons of historical and current topographic maps revealed that land formerly consisting of coastal swamp and forest, mangrove forests, sandy beaches, and rubber and oil plantations have been lost to large-scale land reclamation and urbanisation. Between 1960 and 2015, there were increases in urbanised area, reclaimed land, and artificial shoreline extent. The total extent of mangrove forests has remained relatively stable but this balance is characterised by significant losses on the east coast coupled with increases on the west coast. Coastal development on the island is still on-going with plans for the construction of five artificial islands and another two coastal reclamation projects are either underway or scheduled for the near future. If the plans for future land reclamations are fully realized, 32.3 km2 of the 321.8 km2 island (10%) will be reclaimed land and the associated negative effects on the island’s natural coastal habitats will be inevitable. This study highlights sections of the coast of Penang Island in need of effective monitoring, conservation and management and explores the possibility of incorporating ecological engineering into development projects, either prospectively or retrospectively, to create more environmentally-friendly urban environments and to promote educational, amenity and economic activities. With coastal development taking place on a global scale, opportunities to balance development needs with conservation strategies abound and should be integrated into present and subsequent projects to protect these coastal ecosystems for future generations

The Role of Citizens in Detecting and Responding to a Rapid Marine Invasion

Documenting and responding to species invasions requires innovative strategies that account for ecological and societal complexities. We used the recent expansion of Indo-Pacific lionfish (Pterois volitans/miles) throughout northern Gulf of Mexico coastal waters to evaluate the role of stakeholders in documenting and responding to a rapid marine invasion. We coupled an online survey of spearfishers and citizen science monitoring programs with traditional fishery-independent data sources and found that citizen observations documented lionfish 1–2 years earlier and more frequently than traditional reef fish monitoring programs. Citizen observations first documented lionfish in 2010 followed by rapid expansion and proliferation in 2011 (+367%). From the survey of spearfishers, we determined that diving experience and personal observations of lionfish strongly influenced perceived impacts, and these perceptions were powerful predictors of support for initiatives. Our study demonstrates the value of engaging citizens for assessing and responding to large-scale and time-sensitive conservation problems