Becky Hitchin highlights two environmental projects calling out for diver assistance – why not get involved ?
BECKYHITCHIN
Restoring British seas
Becky Hitchin highlights two environmental projects calling out for diver assistance – why not get involved ?
We ’ ve all got diver friends who have gone to far-flung places and participated in coral reef restoration initiatives . But there are also projects that divers and snorkellers can get involved with in the UK . Today we ’ ll talk about seagrass and oysters .
Seagrasses are flowering plants that live underwater in shallow , sheltered areas around the coasts of the UK and elsewhere . The meadows they form are biodiversity hotspots and fish nurseries , and also hinder coastal erosion by reducing wave energy . They promote ocean health by filtering pollution . The oldest seagrass meadows are thought to be hundreds of thousands of years old and are significant carbon sinks – the Marine Conservation Society estimates that one hectare of seagrass can store around 400kg of carbon dioxide per year .
It is estimated that 92 % of seagrass off British coasts have been lost in the last century . However , the loss of this precious ecosystem is starting to be reversed , with active restoration schemes being
Britain ’ s seagrass meadows are a habitat for many forms of life , including this egg-laying nudibranch developed in several places around the UK . The restoration process is simple . Seagrass plant seeds are harvested and collected from known seagrass meadows . The seeds are sorted , with suitable seeds placed in small hessian bags that degrade naturally . These seed-filled bags are then laid and planted on the seafloor .
Project Seagrass estimates that over 2,000,000 seeds have already been planted , using more than 3,000 volunteers in an incredible effort . Work by Swansea University aims to restore 2 hectares of seagrass meadows in Wales and Scotland , and WWF is working to restore 10 hectares around the Llwyn Peninsula and Anglesey . The Ocean Conservation Trust are coordinating projects in Plymouth Sound and the Solent that aim to restore 8 hectares . In Scotland ,
“ It is estimated that 92 % of seagrass off British coasts have been lost in the last century ”
Restoration Forth aims to restore at least 42 hectares of coastal habitat , including seagrass , by 2030 .
Including seagrass , they say ? What else is there that is available for practical restoration that communities , divers and snorkellers can be involved in ? One answer is oysters .
Oysters are as amazing as seagrasses . Again , they can provide habitats for fishes and seabed organisms , providing complex reef structures that can provide habitat and refuge for a wide range of organisms . Oyster reefs improve water quality and store carbon . They also reduce excess nutrients in the water . As with seagrasses , our oyster beds are a shadow of what they once were . Native oyster populations have declined by 95 % in the UK since the mid- 19th century , with collapses in the mid- 20th century due to overfishing , pollution , disease and the introduction of invasive species .
How , then , are oyster reefs rebuilt ? The simplest rebuilding occurs where some suitable habitat remains , and release of oyster larvae into the water column should restart reef growth . In other places , they have to be helped a bit . In their larval stage , oysters anchor themselves to hard substrate on the seabed , where they live and grow . For restoration , old shells are put to new use . Oyster larvae can then settle on planted shells to kickstart the evolution of a new oyster reef . Blue Marine Foundation has also placed brood stock oysters in cages hung in the water beneath pontoons , facilitating the release of millions of larvae into the Solent . Restoration Forth is working to deploy new beds of native oysters into the Firth of Forth , reestablishing a habitat that has been lost for more than 100 years . So next time you ’ re stuck for a new reason to go diving , find a local initiative , pick up your fins and get stuck into giving something back to the seabed we all love . �
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