Coquina

COQUINA AND THE DEERFIELD ISLAND PARK COQUINA TRAIL

What is coquina? Let’s dig in for a small “upper middle school” geology lesson.

Geoscientists describe coquina as a sedimentary rock formed mostly by shell fragments of calcium carbonate which are loosely cemented (quite porous) together by calcite and is technically a variety of limestone. However, coquina has a noticeable lack of sand, silt, and clay due to the strong currents of water that wash small grains away. The fossils are usually mollusk or gastropod (slug and snail) shell fragments. These fragments accumulate in high-energy marine and lake type environments where currents and waves result in the vigorous abrasion/fracturing of the shells that compose them. These environments would include beaches, swift tidal channels, shallow

submarine raised banks, and barrier bars. Coquina gets its name from a Spanish word for “shellfish” and inherits its’ color from the shells which tend to be off white and light gray with sprinkles of blues and oranges.

Our Coquina Trail on Deerfield Island Park (DIP) received its name due to the sediment pulled from the Intracoastal and Royal Palm Waterways (back in the 1960’s). This newly cut waterway was full of coquina shells which were primarily dumped on the north and northeast portion of the Island. The date of naming the trail is unclear but earlier 1990 DIP maps indicated a “Coquina Trail”.

Over the years the trail has changed its path due to tortoise activity and storms. In 2017 it was damaged heavily by Hurricane Irma requiring previous park staff (Katie and Armagan) to recut a new trail around the existing damaged trees. These downed trees encouraged tortoises to seek refuge along the trail; therefore, creating some of our largest tortoise groups to live just off the Coquina Trail.

Currently the “Coquina Trail is Under Renovation.” The Parks staff is striving to remove Australian Pines while at the same time respecting the tortoise habitat locations. The trail is approximately ½ mile long and runs primarily on the east side of DIP. Visitors will not see coquina any longer but will enjoy moderate shade and an intracoastal viewing area with benches. Decisions will be made within the next few weeks as to what type of path the Coquina Trail will see next…will it be a rubberized material or a modified natural trail?

Submitted by: Karen Hutson

Thank you Katherine Hendrickson for your history input.