Survival of salmonellas in a colony of common Black-headed Gulls Larus ridibundus between two nesting periods

In September 1993 and January and April 1994, we studied the prevalence of salmonellas in the soil of an island of a colony of the Common Black-headed Gull Larus ridibundus at a group of ponds near Hodonin, Czech Republic. Fourteen strains of Salmonella typhimurium, one strain of S. derby and one strain of S. bareilly were identified in a total of 64 soil samples. Salmonellas were demonstrated on all three sampling dates, although their prevalence in April 1994, i.e., at the time when gulls in the colony already had eggs, was low. Salmonellas survived in the soil of the colony throughout the period between nestings.