Much of the seagrass in the North East has been lost over the past century, and so a key focus of the research that Stronger Shores will undertake is to identify which factors are critical to successful seagrass recovery in the region. Crucially, and unique to the Stronger Shores project, we hope to get a better picture of how effective seagrass meadows are at reducing wave energy - an important ecosystem service that can help to slow the rate of coastal erosion. This will allow us to better understand how the restoration of seagrass meadows can complement traditional coastal defences such as seawalls and breakwaters, bringing with it additional wider benefits such as enhancing biodiversity and improving ecosystem health.
At one point in history seagrass was so abundant that it was a staple of local industry, being used as insulation in homes, as pillow and duvet stuffing, and even suggested as an alternative to cotton. However, seagrass populations have drastically declined throughout the 20th century. Poor water quality, harmful fishing practices, and a wasting disease that spread through the seagrass populations in the 1930s are all believed to have contributed to the estimated 44% decline in seagrass around the UK and Western Europe.
To investigate how seagrass might be successfully restored, our seagrass and seaweed research officer, Martina, will be undertaking small-scale restoration trials across selected sites to look at the impacts these trials have on biodiversity and the surrounding water properties. We have identified eight sites stretching along intertidal areas of Northumberland’s rivers, generally in mudflats, which have either current or historical records of seagrass. If we find seagrass at any of these sites, then the mapping work will begin to understand its extent in that local area.
Once this work is complete, we will choose three of the sites to run small scale restoration trials. First, we will establish the environmental ‘baseline’ for each site so that we can understand how any subsequent changes we make are impacting the site. Once we have a baseline, we will then introduce small frames that contain seagrass seedlings grown from locally sourced seeds and we’ll then monitor these on a monthly basis for the next year.
By collecting the data from our sites over the next year, Martina will build a picture of the role that seagrass plays in intertidal ecosystems, and how seagrass habitat restoration can be harnessed to increase biodiversity in our local coastal areas and provide important habitats and food for birds and crustaceans. We will also get a better understanding of just how effective this wonder plant is at clarifying and oxygenating the surrounding water, providing valuable benefits for many marine species.
Whilst the seagrass restoration community are building a good understanding as to which factors are important to seagrass, the success of different restoration approaches is very much dependent on the location where restoration takes place. There are many factors that come into play. For instance, tidal movements and human pressures from recreational and industrial activities differ between locations, and so may affect the success of restoration efforts at different sites.
Ecological competition for space is also an important element to consider, particularly since algae is known to smother seagrass at some sites and prevent it from growing. By using multiple test sites along the Northumberland coast, each with unique environmental conditions, we can investigate which factors are critical to healthy seagrass growth in that area, and therefore, add to our understanding of how to achieve successful restoration. This learning will be added to a Stronger Shores toolkit, alongside knowledge and experience that we gain from working with partners in other organisations such as Tees River Trust and Newcastle University, and contribute to a guide of best practice for marine restoration work in the North East of England.
Our hope is that this research over the next couple of years will culminate in a feasibility study which can inform us about which areas might be most suitable for larger scale restoration work after the completion of Stronger Shores, and a clearer image of the benefits that seagrass restoration would bring to our region.
This project is funded by Defra as part of the £200 million Flood and Coastal Innovation Programmes which is managed by the Environment Agency. The programmes will drive innovation in flood and coastal resilience and adaptation to a changing climate.