- August 6, 2024
196 of the world’s nations are committed under the Kunming-Montreal Global Biodiversity Framework to tackling nature loss. Habitat restoration is a major pathway to tackling this loss. For marine habitats such as seagrass, such restoration is often portrayed as an easy answer to fighting many of our planetary ills causing this nature loss. But as evidence grows of the issues and challenges of such activities, scientists from Project Seagrass and Swansea University have outlined ten golden rules to help improve this restoration. Their work is published today in an Open Access article in the journal Plants People Planet.
The article responds to the increasing pressures faced by seagrass ecosystems globally and the need to rapidly rebuild marine life. The authors highlight throughout that in order to restore our ocean biodiversity, we first need to focus on reducing the stressors to these habitats, namely water quality, boating and coastal development. The authors who have been studying seagrass conservation and restoration argue for a shift beyond a singularised view of restoration as being about planting new meadows to a combined view where damaged and fragmented meadows are rejuvenated; threatened and diminishing meadows are protected; and more meadows become resilient. The rules confirm the need for collaborative approaches to restoration which create biodiverse ecosystems that support coastal communities and improve communities.
Dr Richard Unsworth, lead author on the paper who is the Chief Scientific Officer at Project Seagrass and Associate Professor at Swansea University said, “To rebuild marine life at the scale and speed required to fight the biodiversity crisis and the climate emergency we need to think bigger, whereby we bring degraded habitats back to life at the same time as creating vast new habitat in support of coastal livelihoods, and community resilience”
The paper has been published following the International Seagrass Biology Workshop (ISBW15) hosted in Naples, Italy earlier this year, the theme of this which was “Seagrasses in the Anthropocene”. As human activities place ever-increasing pressure on seagrass ecosystems at both a local and global scale the resulting changes in environmental conditions have altered seagrass ecosystems to an extent that has not previously been observed. The challenge currently facing the global community is the need to establish a new baseline and protect, restore, and rehabilitate the seagrass ecosystems that currently remain.
Dr Benjamin Jones, Chief Conservation Officer at Project Seagrass and author of the paper says: “Coastal environments suffer from excess nutrients and contaminants from poor land management, deforestation and ineffective pollution management. If we are to place seagrass on a pathway to global net gain, for restoration to have any meaningful contribution, we also need to think about restoring watersheds and thinking upstream – restoring the land to restore the sea”.
The ten golden rules originally developed by Unsworth and Jones for seagrass restoration, and outlined below, aim to ensure that existing seagrass is protected, that multiple and diverse stakeholders are involved in planning to support the selection of appropriate sites and ongoing stewardship, that appropriate restoration methods are utilized, and that realism is adopted in the face of the challenges surrounding global restoration efforts particularly in light of ongoing climatic pressure.
Dr Leanne Cullen-Unsworth, CEO at Project Seagrass and an author of the paper says: “Fantastic progress is being made in the field of conservation and restoration of seagrass meadows, but in order for this to happen at the scale and speed required, we wanted to set out a series of holistic guidelines, based on available research and experience, that practitioners can follow for improved chances of success.”
10 Golden Rules for restoration to secure resilient and just seagrass social-ecological systems (set out in detail below)
- Protect existing seagrass first
- Work together
- Create biodiverse ecosystems with multiple functions for people and planet
- Select appropriate sites for restoration
- Determine appropriate restoration methods
- Use resilient plant materials and future proof your project
- Maximize the potential opportunity of the restoration
- Plan ahead for infrastructure, capacity, and restoration material
- Develop realistic informed goals and reporting
- Make it pay
10 Golden Rules (Detailed summary of the paper)
1. Protect existing seagrass first
Amidst the context of growing interest in seagrass restoration, the authors emphasize that it is much slower, more difficult, and more expensive to re-plant seagrass meadows than it is to protect those that currently remain.
Protection from localized stressors can relieve pressure on our existing seagrass be this through the implementation of improved water quality from better catchment management, reduced boating damage, establishment of Marine Protected Areas or through the encouragement of alternative low-impact livelihoods, tourism, and fishing practices. The authors also outline the need to prioritise which seagrass meadows to protect taking into consideration predicted future climatic conditions such as changing temperatures, sea level rise, land use change, and the gradual topicalization of temperate systems.
2. Work together
Restoration is a collaborative process and the authors discuss the importance of the involvement of multiple and diverse stakeholders, expertise, and experience throughout all stages of the restoration process.
Seagrass social-ecological systems support diverse uses and livelihoods, from fishing and recreation, to harvesting of raw plant material. Rights and equality are central, and stakeholders should be encouraged to continue activities, not just undisturbed, but enhanced by increased seagrass resilience.
Engaging local communities and stakeholders during the site selection period is essential as these groups will often become the long-term custodians of the restoration site.
Without working together, long-term seagrass restoration at scale is simply not possible and finding ways to bring people together to co-design restoration projects will enhance the social capital of resulting habitats.
3. Create biodiverse ecosystems with multiple functions for people and planet
The overarching aim of seagrass restoration should be to maximise the biomass and biodiversity of meadows such that they support diverse and resilient ecosystem functioning and services for people and planet.
The authors discuss how natural systems simultaneously produce multiple ecosystem services that interrelate in complex and dynamic ways. An overly narrow focus on a limited set of ecosystem services can lead to regime shifts with unfavorable and unexpected sudden loss of services in addition to stakeholder conflicts surrounding the perceived benefits and disbenefits of restoration.
An example provided by the authors includes the increasing evidence that unregulated conservation of seagrass-associated green turtles may negatively affect seagrass itself, with unintended consequences for fisheries and other ecosystem service delivery.
The complex nature of seagrass social-ecological systems means that any one of a range of human activities could be perceived as a threat to restoration focused on only one or two ecosystem services in isolation.
4. Select appropriate sites for restoration
A rigorous process of seagrass restoration site selection is required to maximise the chances of success including clear objectives encompassing restoration needs, area of habitat restoration, intended benefits and anticipated beneficiaries.
Habitat suitability modelling can be used to commence the decision making, identifying potentially suitable areas according to the data currently available, but as the authors have shown in North Wales (UK) they are not always of sufficient resolution.
Environmental factors such as sediment movement, hydrodynamics, light availability and nutrients should be considered for site suitability, alongside biological parameters such as the density of bioturbators, algae and grazers, all of which may interfere with restoration, but may sometimes have positive effects.
The authors again emphasize the fact that seagrass restoration is more than a purely biological process with the need for decision makers to also consider social attitudes, opportunities, and costs when selecting restoration sites.
5. Determine appropriate restoration methods
The authors discuss that although guidance exists on certain tried-and-tested seagrass planting techniques, a common set of guidelines setting out the parameters for seagrass restoration success is not yet possible.
Given the current high cost and uncertainty of planting approaches, indirect methods to remove pressures and promote natural recovery of degraded meadows may often be more suitable and successful.
For example, evidence from the UK suggests that replacing traditional swinging boat moorings with AMS reduces seabed scour and could lead to recovery of at least 6 ha of seagrass nationwide.
6. Use resilient plant materials and future proof your project
The authors go on to discuss the long-term cost benefit of planting new habitats for a species that is likely to disappear in the next decade.
Range shifts for individual seagrass species with respect to sea temperature are likely already widespread with the authors referencing research from the USA indicating that the southern range limit of Zostera marina on the US east coast is projected to migrate hundreds and possibly thousands of northwards, resulting in substantial losses along the eastern coast of the USA.
Climate stressors may also act more aggressively on seagrass at different life stages (e.g. seedling survival) and at different times of year, influencing when seeds can be collected and their abundance and viability. Practitioners need to consider how to integrate future climate projections into projects, by adapting methods based on long-term climate predictions (e.g. expected intensity of an El Nino event) and considering sea-level projections to model the environmental window for where different seagrasses may thrive into the future.
7. Maximize the potential opportunity of the restoration
By thinking of restoration in terms of biodiversity enhancement at a range of scales we move towards improving the integrity of the whole seascape and progress towards rebuilding life in our oceans.
This rule highlights the need for resources to be maximized to achieve the greatest potential system-wide benefits and resilience within the coastal seascape.
8. Plan ahead for infrastructure, capacity, and restoration material
The authors emphasise the need for a development period before embarking on any planting-based restoration projects. This provides a means of reducing project risks, whereby decisions about sites and methods can be made based on good science, local data, and knowledge of the literature.
Just as it is necessary to pick the right biological conditions for seagrass restoration, so too is it essential to ensure the right social governance structure for projects to ensure local community buy-in. Developing a stakeholder engagement plan and delivering it creates a means of de-risking the outcomes of a project through an instilled ownership and resulting stewardship of the restoration sites. Understanding marine spatial plans, infrastructure master plans, major economic development processes and political aspirations is also essential to effective project planning.
The authors experiences of working closely with stakeholders in South West Wales (UK) illustrate how project success and failure can hinge on developing strong community relationships.
Planning with flexible project management and a good project risk assessment is critical, as many seagrass restorations will result in unexpected outcomes and shocks. Birds overgrazing, poor seed development and therefore availability, or adverse weather are examples of common shocks that result in setbacks. Such issues may lead to changes in project workplans, timelines, costs, and ultimately delays with the need for funders to understand that these sorts of issues are commonplace in projects.
9. Develop realistic informed goals and reporting
As global environmental policy increasingly embraces Nature Based Solution, the need to inform decision makers, funders, and the public about the effectiveness and uncertainty involved with seagrass restoration has never been greater.
There are significant structural problems related to scientific publishing linked to the limited and largely absent reporting of experiments that produce so-called negative results e.g those that do not support the tabled hypothesis.
The authors suggest that a ‘learn by doing’ approach on the scale of the wider restoration community rather than individual projects would support restoration efforts and collective learning from failures in the field.
10. Make it Pay
Seagrass restoration is expensive, and to date has been largely funded through philanthropic and government funding mechanisms. Mechanisms are required to generate finance for seagrass protection and enhancement, as well as for improved chances of successful restoration projects. Seagrass protection and enhancement is a priority for restoration (Rule #1), but funding is far easier to obtain for planting new areas. Innovative financing solutions are required to turbo-charge ocean and coastal preservation and prevent further decline, and accounting for the real holistic costs of projects will likely strengthen such innovation.
The costs of projects largely focus on the immediate outlay of funds for planting, without considering long-term monitoring and management. Projects are mostly local and small-scale and typically focus on active restoration and favour the first tranche of seeds required, rather than the investments needed to facilitate long-term recovery. Finance is largely absent to facilitate long-term restoration along with the required monitoring and maintenance needed to report on its success or failure, plus measures to ensure stewardship and increase the chances of success.
The application of the 10 Golden Rules for seagrass restoration can support a shift towards restoration being viewed in a broad context, whereby seagrass regeneration can be achieved by either planting or by enhancing and facilitating natural recovery.