This week's announcement that dogs help to reduce gull congregations on recreational beaches has heated up the debate as to whether or not dogs should be allowed to go off leash at beaches.
On the pro side, when trained border collie beach patrols chase away gulls, they help to prevent Esherichia coli -- present in gull droppings -- from leaching into beach waters, according to a study presented at this week's annual meeting of the American Society for Microbiology.
The avian poop problem has resulted in swim advisories and beach closings, so dog patrols potentially mean more fun in the sun for people and their pets.
Biologist Elizabeth Alm of Central Michigan University, who co-authored the study, told Discovery News that border collies on patrol at Great Lakes region sites repelled gulls "while at the same time not detracting from the beauty and tranquility of the beaches."
She was quick to add, however, that "the dogs used in this study were not pets, but highly trained professional working dogs under the control of a handler. They were off leash only briefly and only while actively chasing gulls."
Gulls are protected under the Migratory Bird Treaty act, but their populations have risen in certain places, such as the Great Lakes area. Alm attributes that to the protection provided by the act as well as to the gulls' adaptability to humans. Easy food sources, such as landfills and beaches strewn with food remains left behind by beachgoers, can be gull magnets.
Border collies have the instinct to chase, but not to catch, gulls, which are capable of flying to other locations and doing their business.
Not all birds and beach wildlife are so flexible, however.
Alm said, "We made sure that our beach sites were not nesting areas for sensitive bird species such as piping plover, and our beach sites were approved prior to the study as not being piping plover nesting sites."