The "Fido Hypothesis"

by Patricia Bachetti, DVM

Dog waste has probably been a part of human existence since Man's Best Friend was domesticated over 15,000 years ago. Today, the sticky problem of dog waste in waterways has a name. The "Fido hypothesis" describes the idea that stream and beach areas where dogs are allowed to dump increases harmful bacteria in the water. Gut bacteria in dog feces is increasingly implicated in water contamination studies and beach closures, as well as the spread of the protozoal parasite that we share with dogs, Giardia. While we all want to provide our urban pooches with a fun-filled romp at the end of a long day of sleeping, it is critical to understand the importance of picking up that deposit.

Though the majority of dog owners carry a doggy bag and dutifully pick up the doo-doo, a recent study found that 44 percent of dog owners admit to leaving it where it was deposited. Reasons included "It was small," "I won't touch it, even with gloves," "It's fertilizer," and "It goes away eventually." But where it goes is the problem, especially if it's near a creek or beach. Dogs are a source of E. coli, the bacteria most commonly implicated in those beach closures and in food contamination incidents, like the recent lettuce recall. Science can trace bacteria back to their owners, and dogs are often the third most likely source. Keeping dog waste out of the creek keeps it out of the bay and off the beaches.

Other concerns with dogs running in the creek bed include disturbing the sediment used as home for the bugs that fish eat. In addition, the nitrogen in stool and urine can contribute to an overgrowth of algae, causing low water oxygen that impacts fish.

The Sausal Creek restoration efforts over the last decade have led to many more people using the trails, with and without their pets. That's a good thing. The restoration has also allowed the native resident trout to reproduce in the creek, making it one of the few urban streams in the East Bay where breeding occurs. And although many people are picking up their pet's poop, we're hearing from hikers, too. Dog feces are being left creekside, native vegetation is being trampled, and dogs are often running off-leash. As a veterinarian, one of the most common summertime injuries I see is cut feet and pads from dogs running off-leash. That can be prevented by keeping your dog safely on-leash in areas not designated "dog-only."

Here are some suggestions for keeping your dog and the creek safe:

Always walk your dog on-leash when on the trails, and use the doggy bag you carry with you. Pick up any deposits and put them in a garbage can. City ordinance allows dogs to be in Dimond Canyon on-leash only.

For off-leash activities, consider the city dog parks in Joaquin Miller Park, Hardy Park, Mosswood Park, Lake Merritt Dog Park, and Grove-Shafter Dog Park. Dogs are also allowed off-leash at Sibley Volcanic Park, César Chávez in Berkeley, Pt. Isabel in El Cerrito, and other sites listed at the Oakland Dog Owner's Group Web site at www.odogparks.org.

Thank you for helping to preserve your local watershed.

Patricia Bacchetti is Vice President of the Friends of Sausal Creek Board of Directors and can be reached at bacpab\@comcast.net. To find out more about the organization, please visit www.sausalcreek.org, call 501-3672, or email coordinator\@sausalcreek.org.