(Osceola County, FL)  --  Officials think they know what caused so many ducks to disappear from a fish camp in northern Osceola County.  Yesterday, officers of the sheriff's mounted patrol captured a 12-foot green anaconda.  The green anaconda is the largest known species of snake and can grow to 30-feet in length.  Wildlife experts believe this may be the first time such a big snake was caught in the wild in Florida.  Officers think the chilly temperatures made the snake sluggish and relatively easy to trap.  Experts at Reptile World Serpentarium are taking care of the big snake.