The ACA Forum

Conserving the Devonshire Avon from source to sea



July 28th, 2017 | Author: Stuart Watts | Edit

The ACA has collaborated with the AONB Estuaries Partnership in producing a new biosecurity plan, available on the link below, to help stop the spread of marine non-native species in our South Hams estuaries..  Please read it and take note.

Because swimmers’ wet suits and some vessels may have been used on other waterways, it is vital before they are put into the waters of the Avon, that wet suits boats and boards are checked for contaminants, cleaned and dried  – ‘CHECK – CLEAN – DRY’! Non-native species cannot survive long term desiccation.


  • Check all vessels (dinghies, kayaks, SUPs) and equipment (trailers, dive gear etc.) which can be removed from the water and used elsewhere
  • Clean them thoroughly
  • Dry completely before using again


Biosecurity is becoming increasingly important to protect this MCZ environment against encroachment by a wide variety of invasive species.   This biosecurity policy is universal throughout the South Devon AONB.  See

The risks of an invasive non-native species in the Avon are relatively low owing to the regular flushing of the estuary by freshwater but with increases in the number of people and craft using the estuary for recreational purposes, the danger is still present.  Please be vigilant and take any relevant precautions, as advised in the plan.

The effects of invasion by Spartina or cord grass in the Avon Estuary after artificial introduction by Man are all too evident in the steady accumulation of silt and mud.   Multiplication of the Pacific Oyster outside of the farmed racks in our estuary is prevented by limiting the externally-sourced juveniles to triploid (infertile) individuals.

See the full plan here:-