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Coastal wetlands, vital for fisheries habitats, have suffered extensive losses. Ecosystem restoration offers opportunities to improve fish catch and restore the valuable services these ecosystems provide. Successful restoration is dependent on choosing a site where restoration is feasible, which encompasses biophysical, social, governance, logistical, and resource factors. However, factors that influence feasibility such as land tenure (governance feasibility) and future climate risks (biophysical feasibility) are often overlooked in quantitative analyses of site selection. We ask how spatial priorities for restoration change when considering how feasibility is affected by land tenure, cyclone risk, and both factors together. Specifically, we analyzed a case‐study of mangrove restoration to improve fish catch in Queensland, where there is interest in restoring coastal habitats to support fish habitats. We found that the rank order of planning units by restoration feasibility was highly influenced by both land tenure and cyclones, with cyclones changing ranks with clustered regions along the coastline and land tenure variably changing ranks throughout. In planning units where fisheries benefit is expected to be high, but cyclone risk substantially reduces restoration feasibility, practitioners could consider strategically planting mangroves near established mangrove forest and selecting resilient species for restoration. Formalizing regulations for incentives to private land holders and amending legislation for easier permitting are additional suggestions for addressing land tenure challenges. Our study emphasizes the importance of systematic approaches to considering feasibility in spatial planning for restoration to minimize the risk of failure. [ABSTRACT FROM AUTHOR]

Plans for habitat restoration will benefit from predictions of timescales for recovery. Theoretical models have been a powerful tool for informing practical guidelines in planning marine protected areas, suggesting restoration planning could also benefit from a theoretical framework. We developed a model that can predict recovery times following restoration action, under dispersal, recruitment and connectivity constraints. We apply the model to a case study of seagrass restoration and find recovery times following restoration action can vary greatly, from <1 to >20 years. The model also shows how recovery can be accelerated when restoration actions are matched to the constraints on recovery. For example, spreading of propagules can be used when connectivity is the critical restriction. The recovery constraints we articulated mathematically also apply to the restoration of coral reefs, mangroves, saltmarsh, shellfish reefs and macroalgal forests, so our model provides a general framework for choosing restoration actions that accelerate coastal habitat recovery. [ABSTRACT FROM AUTHOR]

Seed‐based seagrass restoration strategies demand precise understanding of the environmental drivers influencing flowering. Flowering varies across diverse spatial and temporal scales, yet environmental drivers' effects on these dynamics have received less attention. Lack of knowledge regarding this life‐history stage limits the advancement of seed‐based restoration efforts, especially the establishment of shore‐based seagrass nurseries to enhance seed production.A systematic literature review on the flowering of the genus Zostera was conducted to develop a conceptual model that links influential environmental drivers with flowering. Additionally, a case study using existing survey data supplemented by additional field surveys was designed to explore the spatio‐temporal variability of flowering along the latitudinal gradient in Australasia for the species Zostera muelleri. Predictive models for flowering times were developed using regional climatic variables, following hypotheses generated from long‐term mesocosm observations.The review identified the direct and/or indirect effects of temperature, light, tidal variation, nutrients, salinity and grazing pressure on flowering dynamics. Four categories of flowering variables were identified based on their implications on restoration, namely, timing, abundance, the ratio between reproductive and vegetative growth and morphological characteristics. The spathe densities varied significantly among sites along the latitudinal gradient. While first (r2 = 0.71) and peak (r2 = 0.68) flowering times showed significant correlation with latitude, first flowering was equally predicted by mean winter air temperature and mean winter solar radiation (r2 = 0.73), whereas peak flowering time was best predicted by mean winter air temperature (r2 = 0.60).Accurate predictions of flowering times can improve conservation outcomes by enabling restoration practitioners to forecast flowering times and subsequent wild seed harvesting. The strong correlation between flowering times and climatic variables suggests future shifts in flowering times under climate change are likely, which is crucial knowledge for maintaining the contribution of restoration projects to seagrass conservation. [ABSTRACT FROM AUTHOR]

Biodiversity offsets aim to counterbalance the residual impacts of development on species and ecosystems. Guidance documents explicitly recommend that biodiversity offset actions be located close to the location of impact because of higher potential for similar ecological conditions, but allowing greater spatial flexibility has been proposed. We examined the circumstances under which offsets distant from the impact location could be more likely to achieve no net loss or provide better ecological outcomes than offsets close to the impact area. We applied a graphical model for migratory shorebirds in the East Asian–Australasian Flyway as a case study to explore the problems that arise when incorporating spatial flexibility into offset planning. Spatially flexible offsets may alleviate impacts more effectively than local offsets; however, the risks involved can be substantial. For our case study, there were inadequate data to make robust conclusions about the effectiveness and equivalence of distant habitat‐based offsets for migratory shorebirds. Decisions around offset placement should be driven by the potential to achieve equivalent ecological outcomes; however, when considering more distant offsets, there is a need to evaluate the likely increased risks alongside the potential benefits. Although spatially flexible offsets have the potential to provide more cost‐effective biodiversity outcomes and more cobenefits, our case study showed the difficulty of demonstrating these benefits in practice and the potential risks that need to be considered to ensure effective offset placement. [ABSTRACT FROM AUTHOR]

As efforts to restore coastal habitats accelerate, it is critical that investments are targeted to most effectively mitigate and reverse habitat loss and its impacts on biodiversity. One likely but largely overlooked impediment to effective restoration of habitat-forming organisms is failing to explicitly consider non-habitat-forming animals in restoration planning, implementation, and monitoring. These animals can greatly enhance or degrade ecosystem function, persistence, and resilience. Bivalves, for instance, can reduce sulfide stress in seagrass habitats and increase drought tolerance of saltmarsh vegetation, whereas megaherbivores can detrimentally overgraze seagrass or improve seagrass seed germination, depending on the context. Therefore, understanding when, why, and how to directly manipulate or support animals can enhance coastal restoration outcomes. In support of this expanded restoration approach, we provide a conceptual framework, incorporating lessons from structured decision-making, and describe potential actions that could lead to better restoration outcomes using case studies to illustrate practical approaches. [ABSTRACT FROM AUTHOR]

Coral reef restoration is an increasingly important part of tropical marine conservation. Information about what motivates coral reef restoration as well as its success and cost is not well understood but is needed to inform restoration decisions. We systematically review and synthesize data from mostly scientific studies published in peer‐reviewed and gray literature on the motivations for coral reef restoration, the variables measured, outcomes reported, the cost per hectare of the restoration project, the survival of restored corals, the duration of the project, and its overall spatial extent depending on the restoration technique employed. The main motivation to restore coral reefs for the projects assessed was to further our ecological knowledge and improve restoration techniques, with coral growth, productivity, and survival being the main variables measured. The median project cost was 400,000 US$/ha (2010 US$), ranging from 6,000 US$/ha for the nursery phase of coral gardening to 4,000,000 US$/ha for substrate addition to build an artificial reef. Restoration projects were mostly of short duration (1–2 years) and over small spatial extents (0.01 ha or 108 m2). Median reported survival of restored corals was 60.9%. Future research to survey practitioners who do not publish their discoveries would complement this work. Our findings and database provide critical data to inform future research in coral reef restoration. [ABSTRACT FROM AUTHOR]

Pollution from land‐based run‐off threatens coastal ecosystems and the services they provide, detrimentally affecting the livelihoods of millions people on the world's coasts. Planning for linkages among terrestrial, freshwater and marine ecosystems can help managers mitigate the impacts of land‐use change on water quality and coastal ecosystem services.We examine the approaches used for land‐sea planning, with particular focus on the models currently used to estimate the impacts of land‐use change on water quality and fisheries. Our findings could also be applied to other ecosystem services. This Review encompasses modelling of: large scale drivers of land‐use change; local activities that cause such change; run‐off, dispersal and transformation of pollutants in the coastal ocean; ecological responses to pollutants; socio‐economic responses to ecological change; and finally, the design of a planning response.We find that there is a disconnect between the dynamical models that can be used to link land to sea processes and the simple tools that are typically used to inform planning. This disconnect may weaken the robustness of plans to manage dynamic processes. Land‐sea planning is highly interdisciplinary, making the development of effective plans a challenge for small teams of managers and decision makers.Synthesis and applications. We propose some guiding principles for where and how dynamic land‐sea connections can most effectively be built into planning tools. Tools that can capture pertinent processes are needed, but they must be simple enough to be implemented in regions with limited resources for collecting data, developing models and developing integrated land‐sea plans. We propose some guiding principles for where and how dynamic land‐sea connections can most effectively be built into planning tools. Tools that can capture pertinent processes are needed, but they must be simple enough to be implemented in regions with limited resources for collecting data, developing models and developing integrated land‐sea plans. [ABSTRACT FROM AUTHOR]

Coastal marine ecosystems can be managed by actions undertaken both on the land and in the ocean. Quantifying and comparing the costs and benefits of actions in both realms is therefore necessary for efficient management. Here, we quantify the link between terrestrial sediment runoff and a downstream coastal marine ecosystem and contrast the cost-effectiveness of marine- and land-based conservation actions. We use a dynamic land- and sea-scape model to determine whether limited funds should be directed to 1 of 4 alternative conservation actions—protection on land, protection in the ocean, restoration on land, or restoration in the ocean—to maximise the extent of light-dependent marine benthic habitats across decadal timescales. We apply the model to a case study for a seagrass meadow in Australia. We find that marine restoration is the most cost-effective action over decadal timescales in this system, based on a conservative estimate of the rate at which seagrass can expand into a new habitat. The optimal decision will vary in different social–ecological contexts, but some basic information can guide optimal investments to counteract land- and ocean-based stressors: (1) marine restoration should be prioritised if the rates of marine ecosystem decline and expansion are similar and low; (2) marine protection should take precedence if the rate of marine ecosystem decline is high or if the adjacent catchment is relatively intact and has a low rate of vegetation decline; (3) land-based actions are optimal when the ratio of marine ecosystem expansion to decline is greater than 1:1.4, with terrestrial restoration typically the most cost-effective action; and (4) land protection should be prioritised if the catchment is relatively intact but the rate of vegetation decline is high. These rules of thumb illustrate how cost-effective conservation outcomes for connected land–ocean systems can proceed without complex modelling. [ABSTRACT FROM AUTHOR]

Among the biggest global challenges for policymakers is the development of land use policies robust to climate change impacts. While diverse fields can inform adaptation, integrated social-ecological assessment of the multiple adaptation options are rare and cannot be easily applied. Here, we build on past studies by undertaking an integrated fine scale and strategic allocation of sea level rise (SLR) adaptation options that can direct policy making. We use models of probabilistic SLR inundation, urban growth, and sub- and intertidal ecosystem migration, to investigate the impacts of different SLR adaptation strategies, and how these can be allocated to best achieve both development and conservation goals. Coastal adaptation will involve trade-offs among development and conservation objectives and these will vary based on the extent to which sea levels rise. There will be trade-offs between conservation objectives regardless of the adaptation options chosen, however, retreat does provide opportunities for enabling the expansion of coastal ecosystems inland. Local governments can save billions of dollars and minimize political conflict between conservation and development goals through integrated strategic spatial planning. Our planning approach both informs policy and is transferable to other coastal regions faced with a rising sea. [ABSTRACT FROM AUTHOR]

Seagrass habitat is globally threatened from the cumulative impact of human activities on coastal ecosystems. Successful conservation and restoration of seagrass requires knowledge of the environmental factors that limit seagrass presence; however, quantifying the relative importance of these environmental factors is a significant challenge., To resolve this issue, a species distribution model (SDM) for seagrass was constructed from a range of data collected at different spatial and temporal resolutions in Moreton Bay, Australia. Mean annual benthic light availability, significant wave height, and sediment settling time (calculated from sediment size distribution) were the environmental factors predicting seagrass presence in the model, which was calibrated and validated using maps of seagrass cover from 2004 and 2011, respectively., The SDM correctly classified seagrass presence/absence in 85% of cases for calibration to 2004 data and 88% of cases for validation to 2011 data., Application of the SDM to 12 regions of 10-100 km2 size within the study area demonstrated that the environmental factors limiting seagrass presence (i.e. either threatening seagrass that is present or hindering its colonization if seagrass is absent) varied substantially between these regions. For example, seagrass presence in the regions Waterloo Bay and Central West was predicted to be limited by their high mud content, while in the region Deception Bay South, light availability was the major limiting factor., The results demonstrate that SDMs need to be developed on a sufficiently broad scale to capture significant variability in environmental conditions. These models can then be applied at finer scales to assess management options based on the local environmental conditions., Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Human activities are altering the processes that connect organisms within and among habitats and populations in marine and freshwater (aquatic) ecosystems. Connectivity can be quantified using graph theory, where habitats or populations are represented by 'nodes' and dispersal is represented by 'links'. This approach spans discipline and systemic divides, facilitating identification of generalities in human impacts. We conducted a review of studies that have used graph theory to quantify spatial functional connectivity in aquatic ecosystems. The search identified 42 studies published in 2000-14. We assessed whether each study quantified the impacts of (1) habitat alteration (loss, alteration to links, and gain), (2) human movements causing species introductions, (3) overharvesting and (4) climate change (warming temperatures, altered circulation or hydrology, sea-level rise) and ocean acidification. In freshwater systems habitat alteration was the most commonly studied stressor, whereas in marine systems overharvesting, in terms of larval dispersal among protected areas, was most commonly addressed. Few studies have directly assessed effects of climate change, suggesting an important area of future research. Graph representations of connectivity revealed similarities across different impacts and systems, suggesting common strategies for conservation management. We suggest future research directions for studies of aquatic connectivity to inform conservation management of aquatic ecosystems. [ABSTRACT FROM AUTHOR]