VERO BEACH — Wading in brackish canal water littered with floating dead fish giving off an overpowering odor, 12 rescuers from Sea World and the Florida Fish and Wildlife Commission saved a mother manatee and her calf Friday.The rescuers worked for more than three hours along a canal that runs parallel between Calcutta and Nassau drives near the Vero Beach Country Club. As darkness descended and with about 50 onlookers cheering them on, rescuers made at least three attempts before successfully netting the mother. Her calf soon followed and they were to be taken to Sea World in Orlando for observation and rehabilitation.The FWC asked Sea World to get involved when about 14 manatees were spotted in the canal reportedly showing signs of stress from the cold snap that has affected sea life throughout the county.The Sea World officials were worried that the calves were not getting enough nutrients from their mothers because the cold waters were hindering their ability to produce milk. Officials were to decide Saturday if they would return to search for other manatees from the group.