Mangrove Research

Mangrove forests are one of the key building blocks that form the basis of our coastal ecosystems.

Close-up red mangrove leaves

These forests are our silent sentinels, standing up to storms, hurricanes, cyclones, and storm surges.

They proved their worth following Hurricane Irma, as the damage to Collier County’s population and associated real estate would have been so much worse without the mangrove systems that absorbed a lot of the storm surge and wind velocity. Protection of the remaining mangrove communities is vital to the future of Florida. Their importance to estuarine biodiversity, protecting shorelines from storms, and sequestering carbon could mitigate future climatic impacts. These amazing forests are the economic foundation in coastal tropical regions and are necessary to maintain quality for people and nature, yet their future is uncertain both here in Collier County and worldwide.

DID YOU KNOW?

Over 50% of the world’s mangrove forests have been destroyed, and the majority of these losses are attributable to human activities.

In Florida, these activities include development along coastal areas and concomitant alterations to hydrology, including dredging, filling, diking, and impounding wetlands.

Conservancy Mangrove Research Projects

Conservancy biologists have been researching mangrove systems since the Conservancy’s inception and have one of Florida’s longest continuous mangrove monitoring projects. Today’s Mangrove research primarily focuses on forests adjacent to human development, such as the Clam Bay Estuary and Fruit Farm Creek – Goodland Die-off. Click the projects below to read more on the Conservancy’s current mangrove restoration efforts.

Mangroves

"Mangroves are inherently resilient. We need to work together to protect, restore when possible, and revitalize stressed mangrove systems, to ensure that we have healthy coastal environments now and in the future."

-Kathy Worley, Environmental Science Director

CLAM BAY

In 1999, the Conservancy of Southwest Florida, in a gesture of goodwill, committed to a long-term monitoring study to assess the overall health of the Clam Bay mangrove system over time, investigate stressors to the mangrove forest, and evaluate possible changes in response to sea level rise.

ANNUAL MONITORING

The Clam Bay mangrove system is under stress from hydrologic alteration and continual impacts from other human-induced factors (i.e., stormwater runoff, impoundment, dredging, etc.). As a result, many mangrove trees can become more susceptible to disease or fungal/insect infestations that can place the long-term viability of the forest in jeopardy.

Since mangrove forests naturally change slowly, monitoring is necessary to determine the relative “stability” of the forest over time. Conservancy biologists annually monitor 12 mangrove plots within the Clam Bay estuary, with the purpose of evaluating forest health and detect deteriorating conditions early so that measures could be initiated (if warranted) to hopefully alleviate stress throughout the system.

Many changes (both favorable and unfavorable) have occurred within the Clam Bay estuary over the last two decades. Recent setbacks occurred in 2016, followed by Hurricane Irma in the fall of 2017, which often delivered the coup de gras to some areas of the forest. As such, the long-term prognosis for this area is uncertain. Yet, the ability of mangroves to bounce back from the brink of annihilation is phenomenal. Given the chance and the right set of hydrologic conditions and circumstances, this system could rebound.

Click here to read the report on Clam Bay Mangrove Assessment Project 1999-2020

Kathy Worley and Taryn (former Conservancy intern) measuring a very old black mangrove tree.
A canopy of mature black mangroves recovering after Hurricane Irma.

Photos From The Field

A ponar sample of seagrass.
A ponar sample of seagrass.
A quahog clam in a benthic sample.
A quahog clam in a benthic sample.

BENTHIC HABITAT ASSESSMENT STUDY

Mangrove and seagrass habitats provide different resources for a diverse community of benthic organisms that live in mangrove mud, seagrass, and/or bottom substrates. These communities are a vital component of the estuarine food web, providing key linkages between primary producers and higher trophic levels. Some are important economically, while others improve water quality by filtering the water or mediating nutrient remineralization within the sediment.

The objectives of this study were to perform comprehensive mapping of benthic habitat distributions in Clam Bay, analyze benthic habitat compositions relative to the geographic location, and perform a visual survey of any benthic species utilizing mangrove prop roots. This systematic benthic sampling was used to characterize sediments and benthic communities and their distribution within the Clam Bay system over time.

Click here to view the report, Clam Bay Natural Resource Protection Area (NRPA) Benthic Habitat Assessment

Goodland Mangroves (8)

"In the early 1990s, this once beautiful black mangrove forest collapsed, leaving a landscape of dead trees. Even mosquitoes avoided this area since there was no life even to sustain them."

-Kathy Worley, Environmental Science Director

FRUIT FARM CREEK

The Conservancy of Southwest Florida has committed its environmental science department to conduct all of the floral and faunal monitoring required to assess the success of the restoration initiative at Fruit Farm Creek since 2012.

restoration efforts

Conservancy biologists have been studying this area since the late 80s, when the forest was still alive. After its collapse in the 90s, our scientists investigated the causes of the die-off, which was determined to stem primarily from altered hydrology caused by the surrounding developments. In 2010, a team of scientists from various organizations, including the Conservancy of Southwest Florida, Coastal Ecology Group, Rookery Bay National Estuary Reserve, City of Marco, Collier County, and local residents, formed a partnership to develop and implement a restoration program within the die-off areas. The goal of this cadre of organizations was to develop and implement a restoration program within the three die-off areas that were present at that time. Since resources were limited, in 2012, it was decided to address the die-offs in stages. We began with a smaller portion of the die-off to test the efficacy of the restoration plan. The future of this area is uncertain as the larger die-off has been lying barren since 1995. The soils have become more anoxic, and the peat has collapsed.  Only extensive restoration has the possibility of revitalizing some of this area. In March 2020, it was announced that funding for the next phase of the project had been secured, and restoration of the larger die-off area will hopefully begin sometime in 2021.

Our contribution to this project is to assess the success of the restoration activities employed at the Fruit Farm Creek from an ecological lens. Comparisons of pre and post-restoration mangrove regrowth and wildlife populations utilizing the project area are used to gauge restoration success. This data is subsequently used to adaptively manage the restoration moving forward.

The restoration of the smaller die-off area definitively illustrated that a mangrove die-off caused by anthropogenic hydrologic alteration can be re-vegetated with mangroves if the mangrove system is “replumbed” to mimic the natural hydrology that existed prior to man-made alterations and tidal flushing is re-established. The southern portion of the smaller mangrove die-off within the near vicinity of the restored tidal channels continues to show promise.  Mangrove saplings and young trees are established, and a canopy is forming. Species of aquatic and terrestrial organisms commonly found in mangrove forests continue to utilize the die-off area, and some crab species are now present.

2012 (Pre-restoration)

Fruit Farm Creek Goodland 2012

2020

Fruit Farm Creek Goodland 2020
Yellow-crowned night heron
Yellow-crowned night heron
Mangrove leaves
Mangrove leaves
Kathy Worley - Conservancy Science Director in the mangroves
Kathy Worley - Conservancy Science Director in the mangroves