Habitats within the IRLAP System consist
primarily of shallow water communities which
comprise some of the most diverse and productive
ecosystems in the United States. Major
ecological communities present include tidal
wetlands, mudflats, oyster reefs, seagrass beds
While many of these communities within and
adjacent to the IRLAP System continue to be
highly diverse and productive, they have
suffered impacts as the result of growth and
development in the region. These impacts
threaten long-term sustainability of the IRLAP
System's natural resources. There have been
losses to wetlands and seagrass acreage, impacts
to oyster reef extent and function, and an
influx of non-native, invasive plants and
animals. In addition, there is the potential for
additional losses of these habitats in the
future from incompatible land use practices and
Significant habitat restoration efforts are
underway and additional opportunities exist to
conserve and restore species diversity within the
IRLAP System. In the last two decades, several
thousand acres of impounded coastal wetlands,
originally altered to control mosquitoes, have been
reconnected to the IRL. Research and monitoring
studies have determined that upon reconnection to
the surrounding marsh, these impacted coastal
wetlands are able to rapidly recruit native
vegetation and exhibit significant increases in the
number of fish species.
Despite their manmade origins, spoil islands have
become an important biological component of the IRL.
Numerous species of native fish, invertebrates,
reptiles, birds, and mammals inhabit the spoil
islands, and the spoil islands support the majority
of bird rookeries in the IRLAP System. However,
without a well-developed vegetated community, spoil
islands can be prone to infestation by invasive
Seagrass habitat within the IRLAP System has
suffered substantial loss over the last several
years. The most recent data indicates seagrass
coverage has declined up to 90 percent in
portions of the IRLAP System due to the 2011
Superbloom. This negated a near decade-long net
increase of seagrass throughout the IRL.
Investigations are ongoing to determine the
factors responsible for the recent collapse in
Oysters are an example of a keystone species in
coastal ecosystems such as the IRLAP System.
Oysters function as filter feeders, helping to
improve water quality. Oyster reefs help
stabilize shorelines, bottom habitats and
sediments and they provide refuge and essential
intertidal habitat for juvenile fishes and other
wildlife (e.g., shrimp, crabs, red fish, sea
trout and wading birds). There is a need to
determine the relative importance of siltation,
disease and altered water quality to prioritize
efforts to conserve this valuable resource. The
expansion of oyster habitat restoration efforts
in the IRLAP System is currently being
Management strategies include:
- Create a waypoint list (including date,
species, and observer) for collected/observed
rare and listed aquatic species.
- Create a map through GIS with species
sighting data overlaid on the Florida Natural
Areas Inventory natural lands map.
- Annually update the species list for the
aquatic preserves and post on the IRLAP website.
- Summarize annual monitoring data for bird
rookeries and shorebird nesting.
- Create a report and maps detailing
distribution of diamondback terrapins and
recommendations for their conservation.
- Complete biannual seagrass monitoring at all
- Design a non-regulatory, voluntary
research/collection application form to help the
IRLAP manager document research monitoring, and
collection/harvest being conducted within the
- Continue and expand the Shoreline
- Continue and expand spoil island enhancement
through the Spoil Island Project.
- Continue and expand shellfish restoration
- Conduct routine exotic species removal on
- Assist other agencies in controlling
non-native plant and animal species.
A wood stork rookery on a spoil
A diamondback terrapin digs a nest
Volunteers planting marsh grass to stabilize the shoreline of a spoil island