According to the recent article in Science Magazine (*) the answer is no, they are not. Dogs? No actually, dogs keep them clean and safe, the main culprit these days is the seagull, whose excrement can be dangerous. Border collies to the rescue. The results of an experiment on a Lake Michigan beach in the State of Wisconsin, USA, bring new hope.
The article states that Escherichia coli and Enterococcus, disease-carrying microbes, are present in the excrement of seagulls. These contaminate not only the beach but also the water in which people swim. The solution? Perfectly simple: teams of dogs were taken to the beaches, and set free to run after the gulls and the results have been staggering: beaches free of seagulls and clean shallow water.
Other more sophisticated experiments, such as oiling the nests, spraying the eggs so that they would not hatch (conducted by the US Department of Agriculture) were less effective. The dog plan was hatched by environmental microbiologist at EPA in Chapel Hill, North Carolina Reagan Reed Converse, who studied the water at North beach, Racine, Wisconsin.
Samples were taken in the first eleven days of August (2011) to find a control bacterial count, then the sampling was repeated nine days after the dogs (two trained border collies) were released. The dogs were trained only to chase away certain types of bird and to leave other endangered or protected species.
The results were remarkable. Lab tests revealed the presence of pathogenic bacteria such as E. coli, Enterococcus, Salmonella and Campylobacter in the first samples (seven out of the eleven days produced positive results). The latter two bacterial pathogens disappeared totally during the nine days the dogs were present and there was a significant reduction in the presence of E. coli and Enterococcus.
So, a natural way to clean up the beaches. As Montgomery Burns of The Simpsons might say, "Release the Hounds"
(*) Microbe-Free Beaches, Thanks to Dogs
by Naomi Lubick on 31 August 2012, Science Magazine
Summary by Timothy Bancroft-Hinchey
Russian President Vladimir Putin is confident that the conflict between Israel and the Palestinian Authority directly threatens Russia's security