Chris Christman, a 38-year Danville resident and retired Marine Corps officer and insurance agent, has been walking around the lake for almost four years, finding it enjoyable exercise. But lately Christman feels that geese have been taking over the park and leaving their excrement as proof. He also said it looks like the geese are keeping the ducks to one corner.
"The concrete around the lake is completely covered with droppings," he said. His walking route would be friendlier if he could walk freely without "stepping in something," he noted.
On his daily walks Christman likes to bring his daughter's pug, Guinness. But his daughter is leery of her dog walking on mess left by the geese.
The geese and the ducks are attracted to the Oak Hill site on Stone Valley Road because of the water, grass and easy access to food. The feeding is what makes some of the birds stay all year instead of continuing on their migratory path.
"If the waterfowl do not have to migrate to find food then they won't," said Jed Johnson, maintenance services manager for the Town of Danville. "Therefore the waterfowl population goes up, the feces from them increases, and the waterfowl become very aggressive."
The bread that people feed the birds has no nutritional value for them and much of it doesn't get eaten, said Johnson.
The leftovers attract rodents and further dirty the park.
White signs with a bold heading of "Important Notice" are posted at the park to explain why people should not feed the waterfowl, but many do not read the signs so don't know it's bad for them.
Although feeding the geese and ducks is discouraged, it is not illegal in Danville and remains a popular activity around the lake. The town contracts with a company called GooseBusters to help keep down the goose population at Oak Hill.
Janice Scott, owner of GooseBusters, mostly uses border collies to chase geese away. The geese see the collies as "faux predators" and fly away or go into the water where the dogs swim after them, but the geese are not harmed.
"Feeding the birds keeps them here and it isn't good for them," Scott said. "It's how, I like ice cream, but I don't need it. Bread is not something they would get in the wild, and wild animals are supposed to find their own food."
The goal of GooseBusters is not to get the birds to leave but to spend less time at the park, leading to less excrement. One goose produces 1 to 2 pounds of droppings a day, said Scott.
Another control measure is egg addling, applying mineral or vegetable oil to the outside of goose eggs, which blocks the pores to prevent air getting to the fetus. The mother goose still continues to sit on her eggs for the five-to-six-week gestation period. Mentally she feels that she has nested for the year, but no goslings are born.
Five to seven eggs is the average nest size and even with a 50 percent mortality rate two to four goslings can be born to a mother once a year.
In the past, the park had to apply for a permit from the U.S. Fish and Wildlife Service to practice egg addling. But two years ago the federal government labeled geese that didn't migrate between certain dates "urban geese," so they are not protected under the Migratory Bird Treaty Act.
Migratory patterns change based on many factors, such as weather, making it hard to decipher between the two groups. This causes some towns such as Danville to "err on the side of caution," explained Scott, and not practice egg addling.
But the newborn population has not been a problem, Johnson said, so Danville has not needed to apply for such a permit.
Yet, Christman recalls seeing one mother with 11 goslings. He said there are currently more geese and more mess than ever. He recently counted more than 100 geese in one afternoon.
Scott attributes the increase in population to food availability, weather patterns, loss of predators and not practicing egg addling. But, she added, "There are a lot of reasons."
"Urbanites" is the name for people who do not have the knowledge to interact with wild life in a good way, and they are the ones who feed the geese, said Sandy Ferreira, park ranger and clean water educator for Fremont, where it is illegal to feed the waterfowl.
She helped lead Fremont's comprehensive plan to control the goose population at its popular Lake Elizabeth. One part of the plan is educational: Rangers pass out informative pamphlets to potential feeders and ask them to throw away any food they brought.
"Education is paramount," she said. "Public contact is primary for enforcing the ordinance. Almost everyone complies once you educate them."
Ferreira's efforts began in 1991 following an avian cholera outbreak. Many geese perished that suffered from poor nutrition as a result of people feeding them moldy food, which had made them more susceptible to disease. After one goose gets infected with the bacteria it easily spreads among the others.
"We are using the most humane and effective means at this point to deal with this issue," said Johnson. "If more serious issues evolve, then we will address those accordingly."