BONAMIA AND OTHER AQUATIC PARASITES OF IMPORTANCE TO NEW-ZEALAND

The degree to which the parasites and diseases of New Zealand fish and shellfish have been studied reflects the commercial importance of the host concerned and the severity of infection. As New Zealand aquacult ure is largely based on farmed bivalve molluscs and salmonids, most at tention has been given to these groups. However, by far the most serio us parasitic disease of bivalves, Bonamia sp. in flat oysters (Tiostre a chilensis), is primarily a problem in wild fisheries. The importance of Bonamia sp. is such that this review will deal largely with bonami asis but will also mention other parasites of New Zealand fish and she llfish. Crustaceans have received very little attention, because only rock lobsters (Jasus edwardsii) support a substantial fishery, and the re are no known parasitic diseases of this species. Marine fishes have been poorly surveyed for parasites, but the presence of Anisakis spp. larvae and cestode plerocercae in fillets are of increasing public he alth concern.