Global warming is filling the plankton-rich waters of New England with death traps for sea turtles. The number of stranded reptiles has multiplied over the last 20 years, turning facilities like the turtle hospital in Quincy, Massachusetts, into specialized wards for endangered animals with maladies ranging from pneumonia to sepsis. The director of rescue and rehabilitation at the New England Aquarium says more than 200 cold-stunned young turtles were being treated Tuesday partly because the warming of the Gulf of Maine has turned it into a natural snare for sea turtles. The animals enter areas of the gulf such as Cape Cod Bay when it is warm. When temperatures inevitably drop, they can’t escape the hooked peninsula to head south