Although it is unlikely there will be manatees present, it is still worth a visit at other times of the year for the educational displays, butterfly garden, and bird watching. Our first visit was "out of season" too (September), but still quite enjoyable.
Probably not. The river in the park is heated by an electricity plant making it too hot in the summer. We were told that winter time is generally the best time to see the manatees because they are attracted to the warm water.
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