Cardiff Harbour Authority

No.26/
2005

Zebra Mussels in Cardiff Bay

Zebra Mussels are a non-native invasive species, probably introduced into Cardiff Bay on a visiting vessel. They reproduce rapidly, and can cause problems if appropriate care is not taken.

Following consultation with the Environment Agency and the Countryside Council for Wales, this notification has been prepared to advise water users on measures to be taken for protection, and to prevent the spread of the mussels as much as possible.

ADVICE TO WATER USERS

1. Zebra mussels grow rapidly and in large masses, which can lead to blockages or restrict engine cooling water intakes, resulting in engines over-heating. They can foul the hull of vessels. Routine maintenance of vessels will limit this build-up and prevent such problems occurring.

2. Zebra mussels have very sharp-edged shells. These mussels will grow on mooring ropes, boat hulls and submerged equipment. Care should be taken to avoid cuts when handling objects that have been submerged in the water.

3. Although Zebra mussels are found at other sites in the UK, Cardiff Bay is the first site to record them in Wales. To minimise the transfer of this species to other freshwater sites, care should be taken when transporting vessels. When ashore, the hull should be inspected and cleared of any attached mussels. Bilge water should be drained out and the bilges rinsed with dilute bleach solution, allowed to soak for one hour and drained. (See FAQ’s for further information)

4. All personal watercraft (e.g. canoes and dinghies) that have been in Cardiff Bay water for any length of time should be washed down using a sponge and dilute solution of bleach before moving the boat to any other fresh water. Avoid run-off of excess bleach solution into watercourses.

A series of FAQ’s are available for your information.

Should you require further information, please contact Cardiff Harbour Authority on Tel: 029 20877900.


Harbourmaster		Tel: (029) 2087 7900
Barrage control		Tel: (029) 2070 0234
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