EL YUNQUE, Puerto Rico — Biologists are trying to save the last of the endangered Puerto Rican parrots after more than half the population of the bright green birds with turquoise-tipped wings disappeared when Hurricane Maria hit Puerto Rico and destroyed their habitat and food sources. In the tropical forest of El Yunque, two of the 56 wild birds that once lived there survived the Category 4 storm that pummeled the U.S.