Seagrasses are some of the world’s oldest flowering plants, and have been around for almost 100 million years. While they looks very similar to seaweed, they are actually more closely related to the plants found in our back gardens. They are the only true marine flowering plants, completing their entire lifecycle underwater.
Just like garden plants, seagrass has roots, leaves, seeds and flowers.
Seagrass beds are commonly referred to as meadows, growing in dense patches that support a huge number of marine animals.
Why is seagrass important?
Seagrass is a key player in the fight against climate change, as it absorbs carbon dioxide up to 35 times faster than tropical rainforests. It also helps protect communities by preventing coastal erosion. Seagrass does this by stabilising the seabed by binding sediments with its dense root systems (known as rhizomes). The long leaves, which grow up to 1 metre in length, also help to slow wave action, reducing the impact of storm damage to coastlines.
Seagrass also provides refuge for fish when they are at the most vulnerable stages in their life cycle, providing a nursery ground for species such as cod, plaice and herring. It supports a vast number of other species too, ranging from tiny shrimp to elegant seahorses.
Unfortunately, due to several threats such as damage by dredging, anchoring and certain fishing methods, along with disease and unfavourable growing conditions caused by poor water quality, the UK has lost more than 90% of its seagrass meadows in the last century.
Save our Seagrass
We have been working to monitor, understand and protect seagrass since 2017.
The ‘Save our Seagrass’ project uses a team of volunteer divers to survey key seagrass sites in Tor Bay. Over the course of multiple dives, six beds – around 52 hectares – of seagrass have been identified, while dozens of species have been identified within these meadows.
In Tor Bay, one of the key threats to seagrass is leisure crafts causing damage while anchoring and creating turbulence in the water. In a bid to protect the beds, we have partnered with Valeport, makers of oceanographic instruments, the Garfield Weston Foundation and marine conservation charity Sea Changers to place three advanced mooring systems in Fishcombe Bay. These systems contain floats attached to the mooring chain that prevent the seabed being scoured.
We have already seen a great deal of support for these moorings, along with a decrease in harmful anchoring within the cove. As well as installing these advanced mooring systems, we have also established a team of volunteer divers to monitor the health and abundance of the seagrass beds.