John Cassady, a research associate with the Florida Fish and Wildlife Conservation Commission's marine research section, said the calf, estimated to be 2 to 3 weeks old, was seen swimming without its mother for at least a week in the basin behind the Key Largo government and cultural center, The Miami Herald reported Friday.
The animal was captured Monday by workers from Fish and Wildlife and the Seaquarium.
Cassady said baby manatees usually remain with their mothers for two or three years and the baby will likely be cared for at the Seaquarium for three or four years until it can be released back into the wild with a satellite tracking tag.
Officials said they do not know what happened to the calf's mother, but said she likely died or abandoned it.
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