Some independent owners of BP gas stations in Michigan say they have switched or are trying to switch brands amid customer boycotts sparked by the continuing Gulf of Mexico oil spill.

Abdel Berry, who owns three BP stations in the Detroit area, is converting two of them to the Sunoco brand. Berry said business is down at one location from 800 gallons to 500 gallons a day.

"It's either change or go out of business," he told the Detroit Free Press for a story Wednesday.

Station owner Fred Asmar said he's under a multiyear contract with BP so he can't switch. He has lowered prices at his Detroit station to bring back customers but business is still down.

BP PLC said late last month that it would offer distributors money back for gas they buy at terminals. BP said the cash is for gallons purchased in June, July and August, and amounts to 2 cents per gallon along the Gulf Coast and 1 cent per gallon in the East and Midwest.

BP has said the package includes volume allowances and reductions in credit card fees that merchants pay when customers use their credit cards to buy gasoline and items in station stores.

Asmar and Berry say they haven't received any financial assistance so far.

BP owns just a fraction of the more than 11,000 stations across the U.S. that sell its fuel under the BP, Amoco and ARCO banners. Most are owned by local businessmen like Asmar and Berry whose primary connection to the oil company is the logo and a contract to buy gasoline.

In a large number of cases, the distributor of BP gasoline also is the owner or operator of BP-branded gas stations. But in some cases, there is only a supply relationship between the distributor and the merchant at the retail location.

Some BP-branded gas stations have reported sales declines of 10 percent to 40 percent from Florida to the Midwest since the April 20 rig explosion and resulting spill that have tarnished BP's image.