Taxonomy of bacteria isolated from a coastal, marine fish-rearing unit

Phenetic data on almost 600 aerobic, heterotrophic bacteria from a marine fishrearing unit were collected and analysed using numerical taxonomic techniques. Reference strains, representing 42 taxa were included in the analyses. At similarity levels of 85% or above, with analyses prepared from the simple matching coefficient (S_SM), 81% of the isolates were recovered in eight major and 43 minor phena. Five of the major phena were equated with Acinetobacter calcoaceticus, Photobacterium phosphoreum and Vibrio spp. (three groups); the three unidentified phena contained Gram negative rods with polar flagella which were considered to be intermediate between Cytophaga/Flexibacter and Flavobacterium (two phena), and Gram variable rods. The surface of healthy turbot ( Scophthalmus maximus L. ) was populated by a diverse array of bacteria, including Alcaligenes faecalis, Bacillus firmus, Photobacterium angustum,'Photobacterium logei' and Pseudomonas fluorescens. Taxa, isolated as pure culture growth from within the lesions of moribund animals, included Alteromonas haloplanktis and unidentified Gram negative, budding bacteria. Vibrio anguillarum was not recovered from any turbot suspected of suffering from 'vibriosis'.