The mystery loss of Tasmanian tigers from mainland Australia was likely caused by climate change and not wild dogs or hunting by Aborigines, scientists said Thursday.

Sea ice cover in Antarctica dropped to a record low this year, scientists said Wednesday, as they warned the frozen continent's unpredictable nature poses growing risks to shipping including tourist cruises.

A massive humpback whale buried on a popular Australian beach after it washed up dead was being exhumed Monday because locals feared its rotting carcass was attracting sharks.

Western consumer giants are polluting oceans by selling products packaged in cheap, disposable plastic to Filipinos, Greenpeace has claimed -- naming Nestle, Unilever and Procter & Gamble among the worst offenders.

Puerto Rico grappled with the prospect of more flooding on top of an island-wide power outage following Hurricane Maria as the death toll from the powerful storm hit 21, most of them on the tiny Caribbean island of Dominica.

President Donald Trump declared Puerto Rico a disaster zone and said Maria had "obliterated" the US territory of 3.4 million people.

Hurricane Maria devastated Puerto Rico on Wednesday and left the entire island without power, bringing deadly winds and pounding rain that sent thousands scurrying to shelters.

Hurricane Maria closed in on the US Virgin Islands late Tuesday as the US National Hurricane Center warned of a "potentially catastrophic" impact from a storm that has already killed at least two people in the Caribbean.

Hurricane Maria strengthened into a "potentially catastrophic" Category Five storm as it barrelled into eastern Caribbean islands still reeling from Irma, forcing residents to evacuate in powerful winds and lashing rain.

After a succession of mixed messages on the U.S. stance on climate change, Secretary of State Rex Tillerson said overnight that the Trump administration was seeking "ways in which we can work with partners in the Paris climate accord."

"We want to be productive, we want to be helpful," Tillerson said on the CBS program "Face the Nation."

Hurricane Maria barrelled towards the storm-battered eastern Caribbean and was expected to strengthen on Monday as it churned along a path similar to that of megastorm Irma earlier in the month. 

The new storm, which the US National Hurricane Center warned could become a "major hurricane", threatens the French territory of Guadeloupe, which was the staging area for relief operations for several islands hit by Irma.