Natural Communities
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Lora Silvanima
Crow Poison
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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 glasswort.
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.
