TULSA, Oklahoma - The Oklahoma Blood Institute says it's in immediate need of O-negative blood.

The organization says it’s all due to a recent spike in trauma patients.

OBI is partnering with Safari Joe's Water Park to get more donors to give blood.

They say they have less than a one-day supply.

"We need about 1,200 donors per day in order to meet the needs of the 160 hospitals, plus, we supply all the air ambulances Oklahoma," said Jan Laub with OBI.

Donors who give blood now through August 30 will get a voucher for two free tickets to Safari Joe's, as well as a limited-edition t-shirt.