Salt Lake is influenced by relict salt water-water
that has remained under layers of sand and shell for thousands of
years, since the land was under the sea. Over time this salt water
mixed with fresh water in the upper aquifer.
Scientist William McLane surveyed lakes along the
St. Johns River in the late 1940s and early 1950s. He found
salinities in Salt Lake as high as 10,700 parts per million, about
one-third the salinity of the Atlantic Ocean at the mouth of the
St. Johns River. McLane also found breeding populations of five
marine crustaceans, two marine worms, and nine saltwater fish.
The salinity of the soil also influences the marsh
vegetation surrounding the lake. In some places, the soil is so
salty that it can be tolerated only by one plant species called
The site of a former cattle operation on unimproved
pastures, Salt Lake WMA still contains many native plant
communities. The area is part of a transitional zone between
temperate and subtropical climates, so it has plant communities and
species from both climates.
Some natural communities have been altered because
in the past natural fires have not been allowed to burn. Historic
cattle and forest management practices have also modified them.
Much of the Salt Lake landscape has not been burned
in 20 years or more. FWC has implemented a prescribed burning
program in the pine flatwoods, scrub, and selected marsh
communities. In many places, roller chopping will be required
before burning can be carried out. Prescribed fire is used to
reduce hazardous fuel accumulation and to increase species
diversity of both flora and fauna. Fire is a natural force in Salt
Lake's uplands and marshes, and many native plants and animals are
adapted to it. In fact, they require fire to survive. Managers aim
to create a mosaic of burned and unburned areas to increase habitat