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Urgent action is required to stem the loss of the world's seagrass meadows, prioritize their protection and recognize the array of ecosystem services (ES) that they provide. The reasons for continued decline are complex, driven by an array of cross-sectoral forces with solutions consequentially difficult to conceptualize. Across most of their range, seagrass meadows are mostly soft sediment intertidal to subtidal benthic habitats comprised of marine angiosperms. Seagrasses occupy six distinct bioregions across the globe and form one of the world's most widespread habitats in shallow coastal waters found on all of the world's continents except Antarctica. Current documented distributions include 125 000 km2 of seagrass meadows; however, some estimates suggest they could cover up to 600 000 km2 of the coastal ocean (Duarte et al. 2010). Seagrass meadows provide multiple ecosystem services to humanity, yet they remain in decline and largely marginalized on conservation agendas (Orth et al. 2006; Duarte et al. 2010; Cullen-Unsworth et al. 2014). Here, we provide a succinct overview of evidenced successful strategies used to improve the resilience of seagrass meadows and propose ‘bite-sized’ actions to assist a variety of stakeholders in taking practical steps to help reverse the decline of our seagrass meadows. Although some large-scale and local losses of seagrass habitat can be attributed to natural events and cycles, direct anthropogenic impacts are the most serious cause of decline (Waycott et al. 2009). Loss is commonly associated with coastal development, including land reclamation, poor land management, overexploitation and localized physical disturbance (Orth et al. 2006; Grech et al. 2012). In addition, seagrasses are increasingly threatened by climatic change, with increased sea surface temperatures resulting in physiological stress, burning and mortality, and sea level rise resulting in light limitation (Short & Neckles 1999). Associated increased frequency and intensity of extreme weather events exacerbate local disturbance (Short & Neckles 1999). Snowballing anthropogenic inputs to the coastal oceans and destructive activities in coastal regions have resulted in world-wide deterioration and loss of seagrasses, with poor water quality consistently highlighted as the most significant and widespread threat (Waycott et al. 2009; Marbà, Díaz-Almela & Duarte 2014). Water quality is of particular concern for seagrasses due to their high light requirements relative to competitive marine macroalgae (Waycott et al. 2009), but the impact of multiple stressors (although poorly understood) is cumulative and synergistic (creating an impact that is greater than the sum of individual stressors) (Unsworth et al. 2015). Seagrass meadows, due to their geographical positioning at the interface of multiple human–environmental interactions (Kenworthy et al. 2006), are particularly vulnerable to multiple anthropogenic stressors. The cumulative effect of these stressors reduces the resilience (i.e. the capacity to resist and recover from stress) of seagrass to predicted future environmental change (Unsworth et al. 2015). Lack of recognition for the value of seagrass ecosystem services also plays a part in their demise, with a general disregard for seagrass meadows fuelled by a bias of popular media attention towards other marine ecosystems. This disregard for seagrasses is particularly counterintuitive given that seagrasses provide and ecological supporting role to adjacent ecosystems as part of a connected seascape (Unsworth et al. 2015). From local to regional scales, threats are typically consistent, but their magnitude and relative impact changes, reflecting varying human pressures (Grech et al. 2012). The best available estimate suggests that seagrass meadows are declining at a rate of around 7% globally (Waycott et al. 2009). Losses are continuing to be reported and quantified world-wide indicating the need for urgent action to halt further loss. More effective management (including mitigation) is required across spatial scales to protect seagrass meadows and promote resilience to long-term and global-scale change (Orth et al. 2006; Unsworth et al. 2015). Improved resilience requires that environmental managers and regulators use the most appropriate strategies for seagrass conservation that reflect the most up-to-date science. This includes consideration of the processes and feedbacks that promote resilience in seagrass meadows. Seagrass status, threats, drivers and level of protection vary across scales; therefore, appropriate protective strategies are site and context specific. Here, we outline eleven practical strategies (applicable at different scales) to help reverse the decline of seagrass meadows and bolster their resilience. The strategies largely consist of ‘bite-sized’ actions, the appropriateness of which will likely be site and context specific, and so they are not presented as a hierarchy but more a series of potential options. Some of the strategies overlap, addressing multiple threats. Poor water quality caused by urban, industrial and agricultural run-off is highlighted as the greatest threat to seagrasses (Orth et al. 2006; Waycott et al. 2009; Grech et al. 2012) and the primary reason for reduced resilience within seagrass systems. Seagrasses are sensitive to elevated nutrients, high sediment loads and chemical herbicides (Orth et al. 2006), which are conditions of increasing prevalence in coastal waters globally. Improved water quality can reduce light limitation by decreasing turbidity and/or algal biomass. It also improves the resilience of seagrass to elevated sea surface temperatures (Unsworth et al. 2015). Water quality issues are complex due to the multiple stakeholders and scales involved, but improvement can be achieved through the cumulative effects of simple actions shared across stakeholders including industries, catchment authorities or other jurisdictions and local communities (Coles & Fortes 2001). Tampa Bay in Florida is an exemplar of how cooperation between public and private sectors can lead to the setting of voluntary but attainable water quality targets that resulted in a significant reduction in nitrogen loading to the coast. Increased nitrogen loads can decrease light availability due to algal overgrowth; consequently, nitrogen reduction can improve seagrass health by decreasing algal overgrowth (Greening et al. 2014). The Tampa Bay cooperative network included several catchment jurisdictions enacting residential fertilizer ordinances during the summer months to help reduce nutrient loading to the coast (Greening et al. 2014). In other locations, community-driven schemes are trading nutrient credits within catchments as a means of reducing nutrient loading and increasing the health of seagrasses. Another successful initiative to improve water quality in the catchments affecting the Great Barrier Reef lagoon has focused on small readily implementable changes that reduce the rate of nutrients reaching the coast such as better farm management to control erosion, controlled use of fertilizer, replanting riparian vegetation and reduction in soil mobilization by excluding feral animals from waterways though fencing and eradication. Prevention of soil compaction by managing vehicle movement can also reduce the loss of soils. In these examples, the ‘management unit’ is the catchment and actions are guided by evidence from empirical research and models designed to drive changes that cumulatively improve coastal water quality. Maintaining biodiversity and the functional balance of the fauna within a seagrass meadow food web is critical to prevent detrimental trophic cascades (Unsworth et al. 2015). A reduction in grazer biodiversity, such as a decrease in green turtles in Indonesia (Christianen et al. 2012), has been shown to reduce the resilience of seagrass meadows to poor water quality. Creating marine protected areas (MPAs) that consciously include and prioritize seagrass conservation can contribute to the aim of supporting seagrass-dependent functional biota. In some cases, specific measures may be required to restore populations of functional species previously abundant at a site. Habitat configuration (i.e. spatial arrangement of different habitat types) and fragmentation are key determinants of functionally important associated faunal species in shallow water habitats (Gullstrom et al. 2008). Appropriate MPA placement therefore needs to consider this spatial variability for improved chances of success. It should be noted, however, that in some cases, although increasing the density of functionally important species through MPA creation can help increase ecosystem resilience, unintended consequences, such as resultant overgrazing, can become problematic (Christianen et al. 2014). Again, decisions should be site and context appropriate. Such decisions need to consider not just the presence or absence of seagrass, but its functional value and its life-history traits so that management is tailored appropriately (Kilminster et al. 2015). Inclusion of seagrass into MPA networks needs to take into account that both present and historical (hence potential future) seagrass distribution and restoration measures may be appropriate (see section Investing in strategic restoration). Creation of MPAs, restoration action or implementation of fisheries management strategies, however, should be coupled with water quality improvement initiatives for longer-term benefit (see section Catchment management for improved water quality). Our understanding of how removal of key functional fish groups affects seagrass (through potential cascades) requires further research, but where data exist it can be used to evidence the need to maintain the trophic balance within seagrass ecosystems. Coastal development (including land reclamation) continues to degrade nearshore seagrasses (Grech et al. 2012). Environmental impact assessments (EIAs) (a term that varies geographically) largely underpin the planning decisions for such developments, but these are plagued by inconsistent methods, limited data and a lack of independent evaluation, leading to perceptions of inadequate scientific rigour (Sheaves et al. 2015). Improved government–science–industry partnerships can facilitate evidence-based decision-making and the design of low to no net impact coastal developments (such as ports, channel creation, marina development, aquaculture facilities). Projects that require environmental impact assessment (EIA) are often designated insufficient time to determine geographical extent, local drivers and temporal variability of seagrass and its associated environment. Decisions are therefore made based on highly limited data potentially exacerbating the threat to seagrass meadows. In areas with rapid coastal development, or in those earmarked for future development, bringing together stakeholders (e.g. regulators, NGOs, industry bodies, private companies, academics) in a cooperative framework to assess, map and monitor seagrass systems will support creation of a temporal and spatial data set to inform the EIA process (Taylor & Rasheed 2011) that can be based on consistent methodologies adhering to high scientific standards (Sheaves et al. 2015). Collaboration of this kind results in cost sharing, rapid and accurate EIA, and allows early engineering decisions to be made that minimize impacts. Availability of data can help streamline environmental approvals and result in management plans that rely on accurate temporal and spatial data. Collaborative data banking can also assist in disaster action plan development for the management, understanding and offsetting of impacts on seagrass meadows in the event of environmental incidents (Taylor & Rasheed 2011). In addition to improving data sharing and increasing scientific rigour, better independent peer review of the EIA process may also improve the chances of avoiding type II errors (i.e. failing to detect the potential for damage to seagrass) (Sheaves et al. 2015). In the process of managing the impacts of coastal development, there is increasing use of biodiversity offsets to mitigate for unavoidable loss (Bell et al. 2014). However, given the poor success rates in seagrass restoration, offsets should only be used where no alternative exists. Furthermore, a recent review of the use of offsets for seagrass meadows in Queensland Australia concluded that this option first requires development of seagrass-specific offset guidelines (Bell et al. 2014). Overexploitation of seagrass-associated fauna and the use of destructive fishing methods within seagrass meadows are global problems (e.g. trampling, bleach fishing in the Caribbean, bait digging and illegal dredging in the Atlantic, seagrass cutting in Indonesia), all reducing the resilience of seagrass meadows and all issues requiring local action (Unsworth & Cullen 2010). The successful control of destructive fishing gears in seagrass (e.g. rakes, digging and dredges) by fisheries authorities on the south coast of England (UK) illustrates the potential for local action to reduce seagrass damage. Regulations, however, require enforcement as well as changes in the law. Fishing need not be at odds with seagrass protection, and some fisheries techniques can be altered to remove or reduce the direct physical impacts of certain gears whilst maintaining fishery productivity, for example replacing dredging with hand collection (hand, rake, dip nets) for scallops. The use of ‘ecolabelling’ such as Marine Stewardship Council (MSC) certification, particularly when such labelling secures a higher priced commodity, can incentivize fishers to use more sustainable (less destructive) collection methods. These initiatives, however, need to be accessible to more fishers. Where fishing techniques are inherently destructive and unsustainable (e.g. bleach, poison or blast fishing), legislation and enforcement to ban these practices need to go hand in hand with education and awareness-raising initiatives with alternatives presented where available and appropriate. Policy and legislation to protect seagrass meadows do exist in some countries and regions (Kenworthy et al. 2006). Management plans also exist, but as is well illustrated by the ineffectiveness of the majority of the world's MPAs these plans remain ‘paper-bound’. Policy and legislation to support implementation, together with local stakeholder support, policing and enforcement, are key to ensuring conservation action that improves the health and resilience of seagrass meadows. For example, where damage to seagrass has been made illegal (e.g. seagrass is legally protected in England as habitat for seahorses under the Wildlife and Countryside Act 1981), mechanisms are required to deter or assess and report damage that can result in proportional penalties. In the European Union (EU), seagrasses are protected under the habitats directive but direct loss from anchor and mooring damage and the impacts of fish farms are commonplace due to a lack of enforcement. Importantly, although the EU habitats directive specifically names Posidonia oceanica, other species widespread across the EU and also under threat do not receive recognition. Mechanisms are needed that can provide top-down support for bottom-up action (i.e. development of policy to support community-based management and action). For example, legislation in Florida provides a mechanism for prosecution and financial penalties following boat-based seagrass damage. Maritime states often have limited capacity or contrivance for damage to seagrass to lead to legal action and appropriate mitigation, even when damage is extensive and has been deliberate and methodical [e.g. widespread mechanical clearance of seagrass to provide bare white sands for tourists in the Caribbean (author observation)]. Clear policies, legislation and mechanisms need to be in place so that regulators have clear pathways to action in the event of an incident. However, this also requires political will in the first instance. Static moorings and anchors can cause ‘scarring’ of seagrass in the sheltered bays favoured by boaters. Further damage accrues due to boat groundings, propeller contact and boat-related pollution. Seagrass density can be reduced to zero, creating ‘scars’ around weighted chains that tear and uproot seagrass shoots and rhizomes within the circular footprint of the mooring (Demers, Davis & Knott 2013). These scars are often pronounced enough to be observed though aerial imagery. Conflict between boaters and seagrass can be diffused by providing designated or mooring areas or through the use of systems that prevent or minimize damage. These systems use and at the of the mooring to weighted chains and are so effective that seagrass density around the is to that of areas (Demers, Davis & Knott 2013). is when moorings are and in seagrass is likely when are However, for seagrass species (e.g. Posidonia the use of alternatives may not result in a net benefit to the seagrass due to the poor rate of this This further the need for and protection and/or restoration Where is not or alternative measures include the use of replacing chains with or protective or replacing with from and anchor systems can also reduce seagrass density Where is a and use of available moorings is an as is to direct into areas from seagrasses. in sensitive areas can reduce physical damage from species are increasingly within seagrass meadows, with evidence that disturbance or altered environmental conditions to seagrass is by an algal such as in the et al. it is that it will to reducing direct physical disturbance will reduce the available for species to as a primary is evidence of the and successful use of simple methods for seagrass restoration through the collection and of The of these methods can to assist with habitat at Seagrass restoration globally have of success et al. need to be better to and and is required to direct restoration et al. but with can or assist with restoration with improved chances of success. of seagrass restoration is an to historical consider the potential availability of future habitat and propose targets that reflect long-term seagrass loss. need to the or public of the value of seagrass meadows. 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