As recreational boaters it is essential to be aware of the protected seabed habitats that lie hidden under the surface of the sea. Understanding why the habitats are so important and adopting best practice when carrying out boating activities, such as anchoring and mooring, can play a big role in securing the biodiversity future of our seas.
Seagrasses form a key habitat of the seabed; they are most at risk from damage and are currently classed as a critically endangered species. The habitat that seagrass provides is essential to the marine ecosystem, it acts as a key breeding, feeding and resting ground for a variety of protected species such as seahorses, cuttlefish, stalked jelly fish, as well as rare seaweeds.
Traditional swing moorings are most commonly used in UK waters, these moorings consist of an anchor, chain and a float. The chains are prone to moving with the tide and in doing so, often scour and abrade the seabed as it pivots around the anchor point. Repetitive damage from anchoring and mooring can result in a significantly lower chance of regrowth of seagrass in that area.
Anchoring best practice techniques
Before you set off, find out if there are any protected seabed habitats in the area that you are intending on anchoring in. Wherever possible, you should choose an anchorage away from sensitive habitats.
Try to target bare sand away from the edge of seagrass beds when deploying the anchor and consider the pivot area of your anchor chain, ensuring that it will not encroach into a protected habitat.
Another tip is to flake out the correct amount of chain (4 x max. depth at high water) or if using a chain and warp (6 x max. depth at high water). This will help keep the length of chain to a minimum and lessen the chance of additional chain abrasion on the seabed.
Advanced Mooring Systems (AMS) have been designed to have less impact on the seabed. There are various AMS designs that exist, with changes often made to the chain (such as through using an elastic component that does not lie along the seabed) or the anchor (through using for example a helical screw pile component rather than a block).
As boaters we can have a significant positive effect on seagrass beds just by making minor changes to our boating practices.
One example of this is to use a designated slipway whenever possible to land and launch your boat. This will avoid the hull, your feet, and trailer wheels coming into direct contact with sensitive habitats in shallow waters and along the shoreline.
Avoiding shallow waters and being conscious of low tides will help to ensure that your boat avoids coming into contact with or running aground on seabed vegetation. If you do run into seabed vegetation, stop immediately and lift your engine. You should then paddle away until you are clear of the vegetation. You should never use your engine to force your way out as it will damage the habitat and your engine!
Seagrass beds are rapidly declining and are becoming especially scarce in UK waters, but if all water users make a conscious effort to ensure that actions such as anchoring cause as little damage as possible, then there is a chance that we may be able to save this essential habitat.
For further information and guidance on sustainable boating, follow The Green Blue on social media: @TheGreenBlue on Facebook, Twitter, Linkedin and @the_green_blue on Instagram. For more details on anchoring best practice and to download the free Guide to Anchoring and Moorings, visit The Green Blue’s website: www.thegreenblue.org.uk.