Mysterious die-off of sea urchins in the Caribbean is "very concerning," scientists say

Sea urchins are dying across the Caribbean at a pace scientists say could rival a mass die-off that last occurred in 1983, alarming many who warn the trend could further decimate already frail coral reefs in the region.

Dive shops first began reporting the deaths in February, perplexing scientists and worrying government officials who are receiving a growing number of reports about dying sea urchins from islands including Antigua, St. Lucia, Dominica, Jamaica, St. Vincent, Saba and the U.S. Virgin Islands as well as Cozumel in Mexico.

"It's very concerning, particularly because it's happening so quickly," said Patricia Kramer, a marine biologist and program director of the Atlantic and Gulf Rapid Reef Assessment, a scientific collaboration to improve reef conditions in the region.