Gull droppings and their effects on water quality

Droppings collected over periods of 24 h, from four species of captive gulls of the genus Larus, were examined for total coliforms, faecal coliforms, faecal streptococci and Clostridium perfringens. Samples were also monitored for salmonellae and representative groups of samples analysed for nutrient content. The occurrence of several types of droppings, characterized by their colour and consistency, was recorded. Daily loads of coliform bacteria indicated that the outputs of the two larger species of gull approximated to values quoted for man; values for other indicator bacteria were however considerably lower in all gull species. Salmonellae were not detected. Daily loads of Kjeldahl nitrogen from each bird varied from 608 to 1819 mg, and total phosphorus from 3 to more than 115 mg, according to species.