Border Collies are effective at reducing gull congregation on recreational beaches, resulting in lower E. coli abundance in the sand. Researchers from Central Michigan University reported the findings at the annual meeting of the American Society for Microbiology.
Gull droppings may be one source of the indicator bacterium Escherichia coli to beach water, which can lead to swim advisories and beach closings. In addition, gull droppings may contain bacteria with the potential to cause human disease, according to Elizabeth Alm, one of the researchers on the study.
At the beginning of the summer, 200-meter sections of beach were arbitrarily assigned to be dog-treated beaches or control beaches. Half way through the summer, the beach sections were swapped, so that dogs were moved to the control beaches and the dog-treated beaches were then left to be untreated controls.
During the summers of 2012 and 2013, researchers recorded the number of gulls at each beach section. Once each week samples of beach water and beach sand were collected and the numbers of E. coli in the samples counted. In early summer, samples from beaches where dogs had excluded gulls had significantly lower E. coli counts compared to control beaches.
"Border collies are intelligent dogs that love to work and could be used by beach managers as part of a comprehensive management strategy to reduce bacterial contamination at public beaches," said Alm.