Sales will likely tumble a bit at Michael's Bicycles in Newbury Park if Amgen lays off up to 1,600 workers at its Thousand Oaks campus.

The way store manager Shawn Murray sees it, it's not a matter of if — just when.

"I am worried," Murray said Saturday afternoon. He paused and then added, "quite a bit."

Murray wasn't alone in this prediction, joining others who spoke with caution about the impending layoffs and their impact on the local economy: a drop in local business and the potential to drive down property values.

But if this all bodes poorly, Murray and others believe such impacts are cyclical, and the area will eventually bounce back.

The number of projected layoffs — 1,600, or 20 percent of the company's Thousand Oaks work force — came from a local Rapid Response representative, who met with Amgen officials Wednesday. A division of the California Workforce Investment Board, Rapid Response provides resources for employees seeking new jobs.

On Friday, Amgen officials disputed the layoff figure but offered no specific information to counter it. The company employs 20,000 people worldwide.

With 8,200 workers in Thousand Oaks, it is Ventura County's largest private employer.

The layoffs are part of the company's plan to restructure after negative Food and Drug Administration warnings on anemia drug labels sent stock market shares downward. Medicare and insurance companies also adjusted how they pay for those drugs. In the second quarter, Amgen's top drug, Aranesp, had a 19 percent drop in sales from the previous year.

Murray's business is likely to hurt a bit because Amgen's corporate culture embraces bikes. The company has purchased many two- and three-wheelers at Michael's, so employees at the biotech giant can navigate the sprawling campus.

Meanwhile, good weather, rural back roads and an abundance of trails in the Santa Monica Mountains enticed many Amgen employees to buy recreational bikes. In recent years, this drove the store's inventory into more high-end products that fetch up to $5,800.

Amgen apparently offers cash incentives to employees who buy bicycles and ride them to work a few days a week, said Bob, a mechanic and salesman at Michael's for 22 years. He declined to give his last name.

"So this is going to be a big deal for us," he said, estimating that Amgen and its employees make up 15 percent of the store's sales.

The layoffs will also likely affect business at Side Street Cafe, co-owner Shelly Benton said earlier in the day as she wrapped up lunch hour.

"It won't be detrimental," Benton said, adding that she's not planning on any staff changes. "We've known it's coming."

Benton could not say exactly how many Amgen employees patronize her five-year-old breakfast and lunch eatery. "We get our fair share," Benton said.

She's more concerned about losing patrons from other nearby businesses in the industrial park where the restaurant is located. Skyrocketing rents are forcing many to close, Benton said.

"It's just going to be a wait-and-see thing," Benton said, adding she's keeping a positive attitude, "and we'll all ride out the storm."

Sharon Duvick, a Newbury Park resident who works for an electrical company, said the layoffs were inevitable.

"I think anybody who didn't see this coming is foolish," Duvick said, sipping an iced tea at a nearby shopping center that's popular with Amgen employees.

As it rode the wave of good economic times, the company hired employees in a flurry, Duvick said.

The company offers employees meals-to-go, day care and dry cleaning services, she said. Amgen budget cuts, however, could leave such service people looking for work elsewhere, Duvick said.

Like Duvick, Newbury Park resident Robin Mathias believes the layoffs will continue to hasten a souring housing market, exacerbated by a dramatic increase in foreclosures and risky subprime loans.

Signs of that problem could be found south of Highway 101 in the cul-de-sacs off Wendy Drive, where several homes with "for sale" signs also carried "just reduced" stickers.

Back at Michael's, employees and patrons alike agreed that property values would suffer.

But if the layoffs uproot people from homes — because they're forced to find employment outside Ventura County — and send property values downward, other folks will buy those homes.

"Everything's going to come back," said Bob, the bicycle salesman. "It may just take a little while."

Homebuyers will still flock to Ventura County because "we have the mountains," he said. "We have the ocean. We have everything available to us in a very short distance."