Thomas and Stephanie Andersen of San Jose said the seagulls appeared at a pair of ponds next to their home in November and the birds have yet to leave, the San Jose Mercury News reported Thursday.
"It sounds like you're at the beach," Stephanie Anderson said. "They squawk all day. They get in fights. And it's a sanitation issue."
The Santa Clara Valley Water District, which uses the ponds to recharge underground aquifers, said the banks of the ponds are now covered in chicken bones, plastic trash and seagull droppings.
"I have seen them in increasing numbers," said Nina Merrill, a water district wildlife biologist. "I've seen them at Dartmouth Middle School, too. They seem to be blanketing the athletic fields. My guess is they are coming from the bay."
She said officials don't yet have a plan for dealing with the birds.
"We need these ponds for groundwater replenishment. If it's a long-term problem we'll have to study it. It's not something we can ignore," Merrill said.