KEY SLIME PIE: Tar balls have washed ashore in Key West, Fla., the U.S. Coast Guard reports, raising fears that the Gulf of Mexico oil spill could soon foul beaches in Florida and all along the U.S. East Coast. It's not clear yet whether the 20 tar balls found in Key West's Zachary Taylor State Park are from the Deepwater Horizon oil slick, but they are similar to other tar balls that have been found in Louisiana and Alabama. Park rangers scouring the beach Monday found roughly three tar balls per hour throughout the day, with the highest concentrations turning up at high tide. Samples were shipped off for lab analysis, the Coast Guard says, and a gaggle of officials will continue monitoring beaches around the Keys for any other signs of oil. The tar ball invasion came just as scientists at Louisiana State University and the University of South Florida warned that a section of the growing oil slick is moving quickly toward the Gulf's loop current, a powerful water stream that would likely carry the crude around Florida and up the Atlantic Coast. A counterclockwise-spinning eddy, or cyclone, adjacent to the loop current is dragging oil into it, they say, meaning it's just a matter of time before the oil is fast-tracked to Florida, a trip that could be completed as early as Sunday. "I see a huge oil plume being dragged in that direction," says South Florida oceanographer Chuanmin Hu. "It's like a river." (Sources: Palm Beach Post, MarketWatch, New York Times, Associated Press)

MINERALS MISMANAGEMENT? The U.S. official in charge of offshore drilling announced his resignation Monday, amid accusations that his agency's close ties to the oil industry led to lax regulation of offshore rigs like the Deepwater Horizon. Chris Oynes (pictured) has worked in the Interior Department for 35 years, more than a decade of which was spent as associate director for offshore energy at the Minerals Management Service, the federal agency that regulates oil drilling. Oynes was promoted to oversee all national offshore programs in 2007, following 13 years as regional chief in the Gulf of Mexico, and took over a department that's widely criticized as being too cozy with the companies it regulates. (For example, the MMS let BP skip a legally required environmental assessment before opening the Deepwater Horizon). Oynes first announced his plans to retire on June 30 the day after the Deepwater Horizon explosion, but on Monday abruptly moved up his last day to May 31. MMS officials deny putting any pressure on him to step down: "This was a personal decision," one tells Politico. "He was not asked or told to retire, period." Meanwhile, Interior Secretary Ken Salazar and other federal officials are being grilled by lawmakers today, part of at least seven congressional inquiries into the oil spill. President Obama will also name a presidential panel to conduct its own investigation, which would be similar to ones that examined the Challenger space shuttle disaster and Three Mile Island nuclear power plant accident, the AP reports. (Sources: CNN, PoliticoMMS, AP)

CLIMATE (CHIEF) CHANGE: The United Nations will soon have a new executive secretary for climate change, and she'll face a hurricane of hurdles as she takes the job just five months before 193 countries once again meet in hopes of drafting a global climate treaty. Christiana Figueres (pictured) of Costa Rica will begin as the new U.N. climate chief on July 1, taking over from Yvo de Boer of the Netherlands, who announced in February that he would step down this year. U.N. Secretary-General Ban Ki-moon appointed Figueres, who has been a member of Costa Rica's climate-change negotiating team since 1995, on Monday to head the U.N. Framework Convention on Climate Change, the governing body that oversees all U.N. climate-change treaties and negotiations. "I come to the secretariat with great respect for the institution and a deep commitment to [the] UNFCCC process," Figueres said in a statement issued by the U.N. "There is no task that is more urgent, more compelling or more sacred than that of protecting the climate of our planet for our children and grandchildren." De Boer announced his retirement after a disappointing outcome at heavily hyped climate talks in Copenhagen last year, which yielded the Copenhagen Accord but not the comprehensive treaty that had been expected. Parties to the UNFCCC will reconvene this December in Cancun, Mexico, to continue the ongoing negotiations, although several member nations have indicated that 2011 is a more likely target for substantial agreements to be made on cutting greenhouse gas emissions. (Sources: AP, Reuters)

PLANT POLLUTION: Invasive kudzu has choked out swaths of native plants while blanketing the Southeastern United States over the past century, but it also might be making air pollution worse, a new study warns. Scientists have discovered that nitric oxide — an ingredient of ground-level ozone pollution — is emitted from soil at twice the normal rate when kudzu is present, which they say is the first evidence of an invasive plant reducing air quality. "The observed doubling of [nitric oxide] emissions under kudzu in Georgia suggests that kudzu invasion could increase regional ozone concentrations as the plant continues to spread through its current range," the researchers write in the Proceedings of the National Academy of Sciences. The reason is that kudzu is a "nitrogen'fixing" plant, meaning it takes nitrogen from the air and converts it to a usable form, giving it an advantage over most other plants, which must get all their nitrogen from the soil. When kudzu's nitrogen-packed leaves eventually fall off and decompose, however, they return more nitrogen to the soil than it originally had, setting the stage for more soil emissions of nitric oxide. Kudzu now covers about 7.4 million acres in the Southeast and is spreading by more than 120,000 acres each year, and the researchers say the plant could result in a 35 percent increase in the number of days when ozone levels exceed EPA limits. (Sources: BBC News, e! Science News)

Russell McLendon

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Photo (Key West beach): National Weather Service Southern Region Headquarters

Photo (Chris Oynes): Minerals Management Service

Photo (Christiana Figueres): ZUMA Press

Photo (kudzu): U.S. Geological Survey

Russell McLendon ( @russmclendon ) writes about humans and other wildlife.