Colony blot hybridization using a VVHP DNA probe derived from the sequence of the hemolysin gene, vvhA, was specific in identifying all V. vulnificus strains, thereby, eliminating the need for any additional phenotypic identification. The colony blot hybridization procedure revealed a sensitivity and broad applicability sufficient for the direct enumeration of V. vulnificus in various natural samples, without the use of enrichment or culturing on selective medis. V. vulnificus was detected in all natural samples collected during August and May at concentrations ranging from $2.1{ imes}10^1;to;4.0{ imes}10^3$ organisms per ml. However, during November and February, when the mean temperatures of the seawater were $12^{circ}C$ and $5^{circ}C$, respectively, V. vulnificus was not detected in any natural samples.