Updated at 1:40 p.m. ET
Oil is washing up on the shores of New Harbor Island off the coast of Louisiana.
An Associated Press reporter saw a pinkish oily substance washing up Thursday on the sands and into the marshland at this part of the Chandeleur barrier islands chain.
It was at least the second time the AP has confirmed oil coming ashore. Oil was seen washing up at the mouth of the Mississippi last week.
On New Harbor island, birds are diving into the oily waters, but they didn't seem to be in any distress. It's nesting time for sea gulls and pelicans and the danger is they may be taking contaminated food or oil on feathers to their young.
There are also numerous dead jellyfish, including some that have washed up on the beach.
A rapid response team will investigate reports that oil from a massive spill in the Gulf of Mexico has reached the Chandeleur Islands off Louisiana's coast.
Coast Guard Petty Officer Erik Swanson says the response team will deploy Thursday to assess the situation.
Two satellite images taken Wednesday morning indicated oil has reached the Mississippi Delta and the Chandeleur Islands.
Homeland Security Secretary Janet Napolitano told reporters Thursday in Biloxi, Miss., the oil spill "could turn into an unprecedented environmental disaster."
More than 10,000 personnel, 270 vessels and dozens of aircraft have been deployed to protect the shore and try to contain the massive spill, Napolitano said, calling the effort an "all hands on deck response."
The secretary also announced she will travel to a staging area in Pensacola, Fla., one of the 10 such areas prepared for the cleanup effort.
The news comes as a 100-ton concrete-and-steel contraption designed to siphon off the oil fouling the Gulfin the sea where a blown-out well is spewing hundreds of thousands of gallons of petroleum a day.
(Scroll down to watch "CBS Evening News" Anchor Katie Couric interview author and expert Mike Tidwell about the massive oil spill in the Gulf and its potential consequences to coastal communities.)
Engineers hope it'll be the best short-term solution to controlling the leak that has only worsened since it began two weeks ago.
The boat hauling the specially built containment box and dome structure pushed off Wednesday evening from the Louisiana coast and arrived Thursday morning.
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The Joe Griffin was expected to meet up with another BP-chartered boat, the Boa Sub C, a Norwegian vessel that will use a crane to lower the contraption to cover the gusher of oil spewing from the seabed - something that has never been tried before at such depths. BP spokesman Bill Salvin said the drop is expected at about noon Thursday.
If it works, the system could collect as much as 85 percent of the oil that's been leaking from the ocean floor after the Deepwater Horizon rig exploded April 20, killing 11 workers.
"We're even more anxious," the Joe Griffin's first mate, Douglas Peake, told The Associated Press aboard the boat. The AP is the only news organization with access to the containment effort. "Hopefully, it will work better than they expect."
It won't solve the problem altogether. Crews are drilling a relief well to take the pressure off the blown-out well at the site, and that could take up to three months. Other possible solutions are also in the works.
More than 200,000 gallons of oil a day is pouring from the well, creating a massive sheen that's been floating on the Gulf for more than two weeks. As it moved closer to land, crews were frantically laying boom and taking other steps to prevent it from oozing into delicate coastal wetlands.
At sea, some boats were using skimmers to suck up oil while others were corralling and setting fire to it to burn it off the surface.
The Joe Griffin, the ship carrying the containment box that will be lowered to the seafloor, arrived Thursday morning at the leak site about 50 miles offshore.
Workers hope to have the device down at the seabed by Thursday evening, but it will likely be Sunday or Monday before it's fully operational and they know if it's working.
@katiecouric: Oil Spill's Impact on Gulf Coast Wildlife