Hurricane Isaac did more than wipe out thousands of swamp rats — it also regurgitated Deepwater Horizon oil along a wide stretch of Louisiana beaches. From AP:

Weathered oil in the form of tar has washed up on some Louisiana beaches from Gulf waters churned by Hurricane Isaac, prompting restrictions of fishing in some waters and tests to determine whether the source is submerged oil from the 2010 Deepwater Horizon disaster. …

Officials Tuesday evening restricted fishing in waters extending a mile off a roughly 13-mile stretch of coastline from Port Fourchon eastward to just west of Caminada Pass. …

The state Wildlife and Fisheries Department said there was a large mat of tar on one beach and concentrations of tar balls on adjacent beaches. [Garret Graves, gubernatorial adviser on coastal issues,] said later surveys found several more mats. The size of the tar mats was not immediately clear. Graves said high water has prevented a thorough examination.

Original caption: “Post Isaac staining on Pensacola Beach Aug. 29, 2012.”

New Orleans lawyer Stuart Smith, who’s representing some local residents who were affected by the spill, has more details and images like the one above. A local radio station reports of oil-coated wildlife.

“One dead oiled brown pelican, one dead oiled clapper rail, one dead oiled common moorhen, and three live oiled wildlife were recovered near Myrtle Grove,” according to a news release from the Coast Guard.

The dead birds were taken to a rehabilitation center in Belle Chasse. Investigators will perform necropsies to determine the cause of death.

Investigators will also work to determine if the oil is from the 2010 BP oil disaster in the Gulf of Mexico.

In a statement to AP, BP suggested that maybe the oil could have come from one of the many other massive oil spills that struck the Gulf in recent history:

As state officials have made clear, it is important to fingerprint the residual oil to determine its origin. If any of it is connected to the Deepwater Horizon accident, BP stands ready to remove it under the direction of the Coast Guard’s federal on-scene coordinator.

Yeah, if. The state of Louisiana seems to have little doubt.

“I’d say there’s a smoking gun,” said Garret Graves, Gov. Bobby Jindal’s top adviser on coastal issues.