My current research is focussed on UK seagrass restoration; Seagrass (or eelgrass) is the world’s only true marine flowering plant and is globally threatened. In the last decade we’ve lost around 90% of this important coastal and marine habitat in the UK. I’m currently the Seagrass restoration lead for The Solent and Isle of Wight for Swansea University and Project Seagrass, a global environmental charity aimed at restoring, protecting, and conserving the world’s seagrass and it’ associated marine habitats. My job is incredibly varied; one day I could be snorkelling and harvesting seagrass seeds, from undertaking in-field experimental and scientific seagrass planting trials to another day presenting my research at an international conference.
Scientific research as well as public knowledge on seagrass (Zostera marina and Zostera nolteii) is limited, although I’m glad to share in recent years its receiving increasing amounts of attention, both in research and in media, and the benefits it brings to our world. This has driven me to pursue a PhD alongside my job which I’m currently studying to uncover some of the unanswered questions surrounding this fascinating marine habitat.
Globally there are 72 species of seagrass, in the UK, however, we have 2 species which both demand different environmental habitats and variables. As a flowering plant, seagrass uses photosynthesis to create energy to grow, reproduce via seed development or through underground root replication to produce a new plant.
Unlike coral reefs and mangroves, the incredible benefits of seagrass meadows are less well known. Seagrass meadows act as fish nursery grounds, where juvenile fish can reside and resist predation in the safety of the seagrass before maturing as an adult in deeper offshore waters. Adult fish and gastropods also use seagrass to lay eggs in the shallower waters where there is larger oxygen exchange, netted dog whelk eggs and cuttlefish eggs can often be found attached to the seagrass leaves and make snorkelling amongst a meadow a delight. In the UK seahorses are the charismatic species that utilise seagrass meadows and in the tropics turtles, manatees and dugongs graze in these habitats. Seagrass supports biodiversity in many ways and can support up to 30 times more species compared to an adjacent sandy habitat; evidencing this important function has made up some aspects of my research. I have been looking into the provisioning and supporting services that seagrass provides for commercial fish species through seine netting and towed video to better inform the commercial fishery sector but also governmental and policy makers. Seagrass leaves also have the amazing ability to filter pathogens, bacteria and pollutants from the water column contributing towards a cleaner safer marine environment.
As a marine habitat seagrass has amazing abilities to contribute towards reducing the impacts of climatic change. It sequesters Carbon as it uses CO2 and locks it within the organic content of the sediment, which may be a reason why you may have heard of seagrass, as this has been relatively documented in the media. As seagrass develops and spreads intertidally or sub-tidally, it can serve a coastal protection function as it slows and dissipates the water and traps suspended sediment, elevating the sediment depth, and stabilising the sediment and therefore protecting the coastal zone. In the tropics, people, and communities also actively fish within this habitat and depend on it for a source of food and nutrition and their livelihoods depend on it.
For 2024, I am undertaking active seagrass restoration at specific sites around the Isle of Wight, this involves baseline and scientific monitoring backed up with years of in-field experimental seagrass planting trials to ensure the methods are appropriate for the site and for success. Summer seagrass seed collection via SCUBA or by snorkelling, allows the collection of large numbers of seeds to be overwintered at our seagrass-specific nursery before we carry out manual planting of seeds or plants in the spring months during suitable tidal windows, carried out usually by foot by beach access. We utilise the natural lifecycle of the plant and give areas a ‘helping hand’ where it is needed. It is valuable to engage with local communities and volunteers during our work so the importance of seagrass to the area can be understood, the connection to the seascape can be made, and allows conservation and protection to be furthered, particularly as local communities become custodians of their local marine habitat. Working with local community through outreach and education and raising awareness of seagrass is another important aspect of the work that I do, and equally important is communicating the research I’ve undertaken through scientific manuscripts, delivering talks at scientific conferences or sharing knowledge with other environmental organisations and stakeholders.
Other aspects of my work as a scientist means I work on other projects, for example I also work on a scientific project tagging Atlantic Blue Fin Tuna (ABT) through catch and release practices during the late summer months through autumn in Welsh waters. The programme allows us to understand the migratory pattern and populations of ABT in our waters but also support sustainable management of this species. Being involved in a study of this kind, to be in the depths of the Celtic Sea and see these apex predators up close, whilst also teaching anglers the best and safest ways to record this data is truly remarkable.
A couple of times of year, as a JNCC surveyor and instructor for Voluntary Seabirds at Sea (VSAS), I teach theory and boat practical sessions for others wanting to contribute towards this important UK seabird monitoring scheme. Seabird population data gives us incredibly important information to understand changes in the natural environment and to manage and protect seabirds - evident in the recent government ban on sandeel fishing in Scottish and English waters from 2024. Sand eels are an important food source for many marine species particularly seabrids such as the Atlantic puffin, one of my favourite seabirds with their charismatic nature! This governmental protection will allow a lifeline for many marine species and seabird populations to recover and thrive.
I really love the work I do and I hope that by reading about seagrass as a marine habitat has either sparked your intrigue or inspired you to learn more. I would encourage anyone to take a snorkel through a seagrass meadow and enjoy the beautiful experience it has to offer.
By Anouska Mendzil, Marine Scientist