Border Collies are effective at reducing gull congregation on recreational beaches, resulting in lower E. coli abundance in the beach sand.
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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.
Source-Eurekalert