Blue Spring State Park is a state park located west of Orange City, Florida, in the United States
The spring in the park (Volusia Blue Spring) is the largest on the St. Johns River. Due to its relatively warm temperature of 73 °F (23 °C), the spring attracts many Florida manatees during the winter. About 102 million US gallons (390,000 m3) of water flow out of Blue Spring into the St. Johns River every day.
Researchers have recorded the life history of individual manatees at Blue Spring since 1978, including births, deaths, and relationships. Manatees migrate to warmer spring water during the colder weather in Florida, and often return to the same spring every year.