Recovery from siphon damage in Donax vittatus (Da Costa) (Bivalvia: Donacidae)

Between 2.5% and 18% of Donax vittatus from a natural population on West Sands beach, St Andrews on the Scottish east coast showed damage to the siphons caused by non-lethal predation by juvenile flatfishes. The percentage with damaged siphons was greatest in summer. Either inhalant or exhalant siphons were affected, in varying proportions, or in some cases, both siphons. In experimental aquaria, Donax vittatus that suffered non-lethal attack by juvenile plaice which resulted in their removal from the sand, rapidly resumed normal activity as evidenced by reburrowing. Wound healing, followed by re-differentiation of siphonal tentacles, took place rapidly following experimental amputation of siphon tips, with the newly-formed tentacles appearing almost normal after 10 days. Re-differentiation of the siphonal tentacles was accompanied by the development of their complement of three types of ciliated sense organs.