It could take months to clean up the estimated 105,000 gallons of crude oil spilled on Tuesday from a pipeline rupture on the Californian coast of Santa Barbara, according to the US Coast Guard.
More than 300 personnel, 18 boats and volunteers worked throughout Thursday to control the spill and clean affected areas of land and ocean around San Refugio State Beach, Efe news agency reported.
"Clean-up doesn't happen overnight... these types of things continue on, perhaps for months," Coast Guard Captain Jennifer Williams told a press conference on Thursday.
Television channels showed images of pelicans, sea lions and other animals, some dead, totally covered in oil.
California Governor Jerry Brown declared on Wednesday a state of emergency in Santa Barbara county after the rupture in the pipeline, owned by Texas-based Plains All American Pipeline.
An investigation is underway to determine the cause of the rupture and the exact quantity of oil spilled.