Mangrove Chapter, Florida Native Plant Society

2023 CHNEP Watershed Summit

Report by Dave Manley
On Wednesday and Thursday, June 21 & 22, I attended the morning sessions of the Summit. As much of the presentation were data dense, and my memory sub-optimal, the voice in these remarks is from the Proceedings Document from CHNEP.

Day One, Morning, First Session

After opening remarks by Jennifer Hecker, CHNEP Executive Director, the first session was about Aquatic Habitat Research.

The first speaker was Dylan Yakich, Fisheries Biologist with the Florida Fish and Wildlife Conservation Commission.

She spoke about the endangered small-tooth sawfish. Sawfish populations are falling due to bycatch mortality from net fisheries, and while conservation, management, and outreach efforts have reduced those threats, the species is still at risk from humans due to entanglement in recreational and commercial fishing gear and various forms of marine debris. Particularly lethal are encircling items such as monofilament loops, rubber bands, hair ties, and ball-bungee cords. Ball bungees (from covers on boat lifts) are became a more frequent problem after Ian. The anatomy of the sawfish is unique, with its rostrum containing numerous tooth-like projections. It is common to find individuals with numerous “teeth” missing or mutilated.

The next speaker, Andrew Wooley, a Fisheries Biologist with Florida Fish and Wildlife Conservation Commission, continued the sawfish conversation with discussion of ontogenetic shifts in habitat used by endangered small-tooth sawfish in Southwest Florida nurseries, including information about sawfish life cycles and tracking data, showing they spend early life in nursery habitats before moving to deeper water when fully grown.

[ontogenetic: the development or course of development especially of an individual organism]

[nekton: free-swimming aquatic animals essentially independent of wave and current action]

The next speaker in this session was Kelly Chase, another Fisheries Biologist, who addressed the Effects of Seagrass Loss on Nekton Communities in Southwest Florida Tidal Creeks. Phase shifts can occur in marine ecosystems because of external stressors. Such shifts from one steady state (e.g., clear water, vast seagrass) to another (e.g., phytoplankton blooms, bare substrate) occur worldwide. Tidal creeks may be especially prone to phase shifts because of their position in the landscape, which exposes them to the brunt of deleterious effects caused by coastal development.

He and others analyzed an eight-year dataset (2014-2022) acquired by 3 fisheries-independent monitoring using 21.3-m seines in tidal creeks on the Cape Haze peninsula of the Charlotte Harbor estuary, identifying a change in fish assemblages that coincided with algal blooms and seagrass loss in a tidal creek downstream of development. Reductions in benthic species, such as rainwater killifish, were offset by increases in the planktivorous bay anchovy.

[benthic: of, relating to, or occurring at the bottom of a body of water]

The last speaker in this session, Matthew Bunting, a fisheries biologist, discussed juvenile Tarpon emigration from Coastal Ponds in Southwest Florida. As you may know, tarpon spend their early juvenile life in coastal ponds, such as at Lemon Creek Wildflower Preserve. How and when they migrate to open estuarine waters is less well known. An acoustic telemetry study that low barometric pressure, high water level, and fish size were important factors allowing for tarpon emigration. Tarpon left during summer king tides in ponds close to tidal creeks, while tropical storm conditions were needed to allow for emigration from ponds farther in the landscape.

The second session addressed Water Quality

The first speaker was Dr. Chris Anastasiou, Chief Scientist at SWFWMD. He discussed the “Hangover Effect: Coupling Seagrass Loss, Macroalgal Growth, & Water Quality in Charlotte Harbor” to frame the effects to the harbor beginning with Hurricane Irma in 2017. From 1988 to the beginning of 2018, seagrass coverage remained relatively stable between roughly 17,000 and 20,000 acres. Between 2018 and 2020, the Harbor lost an unprecedented 4,442 acres of seagrass. Most notably, the east side of Charlotte Harbor, known as “the east wall,” lost half (1,760 acres) of its seagrass. Concurrent with seagrass loss was an explosion of drift and attached benthic macroalgae. This relatively sudden shift from seagrass to macroalgae occurred in the wake of a protracted regional red tide event that lasted approximately 15 months from October 2017 to January 2019. This event followed Hurricane Irma. While red tide was extreme in many coastal areas along southwest Florida, the east wall (and most of the harbor) was largely spared direct impact. We hypothesize that seagrass loss and macroalgal proliferation along the east wall was not a direct result of red tide; rather it was a function of its aftermath, a phenomenon termed “the hangover effect.” During and after the major red tide event, massive amounts of nutrients from dead and decaying organisms were likely released into the water column. Many of these nutrients likely re-mineralized, became bioavailable in the water column, and were rapidly assimilated by benthic macroalgae. Seagrass maps, aerial imagery, water quality data, and hydrodynamic modeling supported the idea that “the hangover effect” at least in part led to the greatest loss of seagrass in Charlotte Harbor in over 30 years. Further study should determine what the effect of Hurricane Ian might be to seagrass loss.

The second speaker was Dr. Miles Medina, Research Scientist, University of Florida, Center for Coastal Solutions. He discussed Water Quality Trends in the Peace River Basin & Estuary. This presentation described empirical work on water quality dynamics in the Peace River basin and estuary between approximately 2000 and 2021. Nitrogen concentrations in the estuary's water column have been elevated and trending upward over the past 10 years, and nitrogen hot spots span the full basin, from the headwaters to the estuary. Phosphorus concentrations in the estuary have been below the numerical criterion for over 10 years, but phosphorus hot spots span the middle to upper basin. In addition, preliminary causal results reveal a potential link between Charlotte Harbor red tide blooms and nitrogen loads from the Peace River basin, suggesting that nutrient loads from the Peace River have broad systematic effects throughout Charlotte Harbor.

The next speaker was Dr. Detong Sun, Lead Scientist at SWFWMD. He discussed Synthesizing Monitoring Data with a 1D Model for the Assessment of Water Quality Conditions in the Caloosahatchee River Estuary, Florida. His talk began by acknowledging that the assessment of changing water quality conditions in an estuary that is susceptible to significant algal bloom risk is a challenging task for water managers. He then waded deep into a data analysis that was, frankly, sleep-inducing. He concluded that his model suggests that the observed chlorophyll could be a good indicator of strength of algal growth, making it a promising synthesizing tool for the assessment of the water quality conditions in the estuary.

The last speaker in the session was Rebecca Cray, an Environmental Specialist, with the Florida DEP. She spoke on Water Quality Trends and Responses to Specific Events in Estero Bay Aquatic Preserve [2005-2022]. Many activities within the watershed have the potential to impact water quality within the bay, such as point- and non-point sources of pollution, hydrological modifications, increased development and associated impervious surface area, and loss of wetlands. Long-term datasets, such as those from Estero Bay Aquatic Preserve’s continuous water quality monitoring program, are invaluable as a resource to assist in advancing our understanding of how human activities and natural disasters within our watersheds may potentially impact downstream estuarine water quality as well as the habitats and organisms that these waters support.

The third session was Public Engagement.

Due to previous commitments, I was unable to stay for this session.

The first speaker was Katherine Rose, UF/IFAS Extension Charlotte County Extension Agent, Florida Sea Grant. Her talk was Citizen Science: A Two-Prong Approach to Addressing Florida’s Seagrass Loss.

Then Debra Childs Woithe, Environmental Lands Program Manager, Manatee County Department of Natural Resources spoke about the Manatee County Environmental Lands Program and Candidate Property Dashboard Enable Prioritizing Land for Conservation Acquisition. The Environmental Lands Program provides for both fee simple and conservation easement acquisition. Anyone can nominate a property for conservation acquisition using an online form.

Four main criteria are used to assess Natural Resource Value in screening and prioritizing land for conservation acquisition: 1) Ecological Quality – quality of species or habitat, degree of alteration or degradation, level of restoration required; 2) Rarity of Species or Habitat – uniqueness, number of threatened, endangered or species of special concern supported; 3) Importance to Water Resources – protection of or degradation to portable water supply or aquatic environment; and 4) Connectivity – proximity to existing conservation lands or planned corridor, size of connection. These specific elements are evaluated to determine how well sites meet the purpose of the Referendum: 1) Drinking Water Protection; 2) Water Quality Protection; Prevention of Stormwater Runoff Pollution; 3) Preservation of Fish Habitat; Preservation of Wildlife Habitat; and 4) Provision of Parks.

Regina Bale, Environmental Education Coordinator, The Water School, Florida Gulf Coast University discussed Engaging K-12 Audiences in Their Watershed Through Use of Geospatial Technologies

Michael D’Imperio, Sarasota County UF/IFAS Extension and Sustainability, discussed Connecting Concepts: Local Youth Relate Water Quality and Macroinvertebrate Biodiversity in a Hands-On LIFE Lab

Dr. Aaron Adams Director of Science and Conservation, Bonefish & Tarpon Trust presented Applying a Terrestrial Conservation Approach to Better Engage Recreational Fishers in Fish and Habitat Conservation Strategy

Finally, Dr. Emily Hall, Senior Scientist and Program Manager, Mote Marine Laboratory & Aquarium discussed the Coastal Acidification Network Stakeholder Feedback Project

Day Two

Session 4, Hydrology

Dr. Shimelis Setegn Senior Scientist, Coastal Ecosystems Section, Applied Sciences Bureau, SWFWMD. Climate Change Impact on Freshwater Inflows to Estuaries: A Case Study in South Florida Coastal Watersheds.
Climate change can have a significant impact on freshwater inflow to estuaries. Changes in precipitation patterns can affect location, quantity, and timing of watershed runoff, potentially causing flooding and increasing freshwater flow into estuaries, bringing high nutrient loads and decreasing salinity. Similarly, droughts can decrease the amount of freshwater flowing into estuaries, harming the estuarine ecosystem and causing damage to aquatic habitats with elevated salinity. His team investigated how changes in daily temperature and precipitation might translate into changes in freshwater inflows and other hydrologic components. This study aimed to assess the potential impact of climate change on freshwater inflows from the south Florida coastal watersheds.

Next, Teresa VanderWaag, Project Manager, Sarasota County, spoke about Alligator Creek Stream Restoration – A Pioneer Project in Fish-Friendly Design. This talk was an uplifting look at a fully funded project to return Alligator Creek to its natural state. The project area is from headwaters to the US-41 bridge where it becomes tidal. The Alligator Creek Basin is approximately 11 square miles in size and is an urbanized drainage basin that comprises approximately 20% of the Lemon Bay Watershed. Historically, Alligator Creek was connected to wetlands, but by the 1940s, hydrologic alterations had reduced connections to the historic floodplain and adjacent wetlands. The creek was deeply excavated and channelized to improve drainage. The steep-sided banks are prone to erosion, causing sedimentation of the creek channel, which degrades important benthic and fish habitats. It is currently an impaired waterbody for nitrogen, dissolved oxygen, bacteria, and chlorophyll. Objectives for the proposed stream restoration and enhancement portion of the project include water quality improvements realized from reducing downstream flow volume, improving denitrification, and stabilization and naturalization (via natural channel design) of the existing creek banks to prevent erosion. In addition, the project will reduce future maintenance costs, provide hydrologic restoration of historic floodplain areas adjacent to the creek, natural systems conservation and restoration, enhanced recreational utilization, and increased wildlife utilization by important recreational fisheries species such as red drum, striped mullet, and snook. Most notably, what makes this project unique is that it’s the first comprehensive natural stream restoration project in the area that incorporates fish-friendly design elements from scientists at Mote. This project directly implements both the Sarasota County Parks Recreation Strategic Master Plan as well as the Coastal and Heartland National Estuary Partnership Comprehensive Conservation and Management Plan. Improvements to water quality and coastal resiliency through stream restoration is a relatively new technique in Florida and Sarasota County is excited to be one of the pioneers in this innovative best management practice technique. Success will be measured in part by the increase of fish species in the basin, prompting Teresa to call it the Venice Snookery.

Next up was Dr. Peter Rubec, Research Scientist, Florida Fish and Wildlife Conservation Commission. He presented “Modeling to Assess Influence of Water Withdrawals on Spatial Distributions and Population Abundance of Estuarine Species in Charlotte Harbor, Florida”. Spatial distributions and population numbers of estuarine species due to changes in freshwater inflows were predicted using habitat suitability modeling. Salinity was the most significant factor in models for most species’ life-stages. The seasonal HSM (habitat suitability modeling) maps produced were very similar between the Baseline and Minimum Flows scenarios for each species life-stage. Most seasonal estimates of population numbers under Minimum Flows were less than the estimates for Baseline conditions. Right.

Session 5 – Aquatic Habitat Restoration

Dr. Paul Julian, Biogeochemist, The Everglades Foundation presented “Evaluation of Optical Water Quality, Light Attenuation, and Freshwater Discharges in the Caloosahatchee River Estuary (CRE).” Seagrass communities are vitally important ecosystems that support estuarine ecosystems across trophic levels. Therefore, understanding the drivers of seagrass distribution and extent in estuary systems is valuable for conservation and restoration efforts. A critical driver of seagrass distribution is how light moves through the water column (i.e., light attenuation) and the availability of light to reach the estuary bottom. The objective of this study was to evaluate optical water quality parameters within the Caloosahatchee River Estuary (CRE) relative to changes in freshwater discharge conditions. During the study period, freshwater discharge significantly increased, resulting in an increase of stressful and damaging discharge events to estuarine indicator species. Concurrent with changes in freshwater discharge conditions, changes to optical water quality parameters including color, chlorophyll-a, total suspended solids, and light attenuation were detected along the estuary. Changes to water management are expected with the implementation of the Lake Okeechobee System Operating Manual that will improve freshwater discharge conditions to the CRE.

JoEllen Wilson, Juvenile Tarpon Habitat Program Manager, Bonefish & Tarpon Trust. Her talk was on “Working with Charlotte County Planning to Protect Sportfish Nursery Habitat.” Coastal habitats are in decline due to development, altered water flows, excess nutrients and contaminants. Because coastal habitats are essential to the juvenile life stage of sportfish species, sportfish populations are in decline. However, current fisheries regulations rely entirely on stock assessments, with standard regulations like seasonal closures, slot sizes and bag limits, and don’t include habitat in fisheries management plans. By using anglers as citizen scientists, Bonefish & Tarpon Trust (BTT) has identified sportfish nursery habitat and habitat condition (natural or degraded) for two economically, ecologically, and culturally valuable species in our area – Atlantic tarpon and common snook. In 2022, the Florida Fish and Wildlife Conservation Commission (FWC) hosted a series of workshops to create a juvenile sportfish management plan for Charlotte County. During those workshops, BTT proposed the creation of a Vulnerability Index (VI – also known as a ‘District Overlay’) that would be implemented by Charlotte County in their permitting software. The VI would overlay juvenile sportfish natural and restorable nursery habitats with current and potential land use to determine which locations are most at risk.

Barbara Welch and Dr. Elizabeth Salewski, Applied Sciences Bureau, SWFWMD, presented “A Snapshot of Changes in Seagrass Habitat Along the West Coast and the Caloosahatchee River Estuary, Florida”. The Comprehensive Everglades Restoration Plan (CERP) aims to improve the quantity, quality, timing, and distribution of freshwater inflows from Lake Okeechobee to the Northern Estuaries of the Everglades. It is anticipated that CERP will improve the hydrology to more natural conditions which will enhance the spatial and structural characteristics of the biological communities, such as seagrasses. To determine the success of restoration, pre-CERP conditions of seagrass habitat in the Caloosahatchee River Estuary have been monitored since 2008. The decline in seagrass cover may be attributed to reduced water quality, including light availability due to increased turbidity or color. The relationship between water quality and seagrass cover will continue to be evaluated as CERP projects are completed.

Kayla Hayes, Environmental Specialist, Florida DEP presented “Progress of Oyster Restoration Project on Cormorant Key in Charlotte Harbor.”

Since Hurricane Charley in 2004, Cormorant Key in Gasparilla Sound-Charlotte Harbor Aquatic Preserve has experienced significant loss of mangroves and oysters along with severe erosion, leading to complete loss of the island over time. Staff at Charlotte Harbor Aquatic Preserves teamed up with Sanibel-Captiva Conservation Foundation (SCCF), Friends of Charlotte Harbor Aquatic Preserves, and 55 local volunteers, from eleven different organizations, for an oyster restoration project on Cormorant Key. On May 17-18, 2022, volunteers shoveled, transported, and placed over 800 buckets of loose oyster shell (~12 tons) on Cormorant Key; accumulating 168 volunteer hours. Cormorant Key was surveyed for oyster density and shell height after 6 months and compared to a nearby reference reef to determine if the restoration was successful. After 6 months, with spat included, Cormorant Key had nearly triple the oyster density than the reference reef, but when spat are removed (oysters<25 min) the reference reef had almost double 16 the oyster density than Cormorant Key. Cormorant Key also had a smaller average shell height than the reference reef. This data indicates there was an initial settlement event at Cormorant Key with a large abundance of spat, but if the reef follows patterns of other oyster restoration projects in this area, the oyster density will drop after 2-3 years and shell heights will resemble those of the reference reef. The one-year restoration monitoring will occur in May of 2023 and Cormorant Key will be monitored annually thereafter.

Session 6 – Hurricane Ian Impacts was the afternoon session.
I was unable to attend this afternoon as well. 

Brandon Moody, Water Quality Manager, Charlotte County Board of County Commissioners spoke about “Interagency Water Quality Response and Observed Data Post Hurricane Ian.”

In the aftermath of Hurricane Ian, multiple agencies and organizations coordinated to collect water quality samples throughout Sarasota Bay, Lemon Bay, Charlotte Harbor, the Peace and Myakka river basins, and the Caloosahatchee Estuary. This presentation will provide an initial examination of Charlotte Harbor and Lemon Bay, illustrating the impact of Hurricane Ian to the water quality of these systems in the weeks following its landfall. In addition, an overview of the logistics behind this effort will be explored, discussing successes, challenges, and lessons learned for future storm response events.

Dr. Chris Anastasiou, Chief Scientist at SWFWMD spoke about “Water Quality in the Charlotte Harbor Watershed After the Passage of Hurricane Ian – Dissolved Oxygen and Nutrient Impacts and Recovery.”

With massive amounts of water moving through the watershed, long-term water quality impacts including bacterial contamination, unprecedented nutrient inputs, harmful algal blooms, and hypoxia were of great concern. In response to these concerns, a coordinated multi-stakeholder team including the Southwest Florida Water Management District (SWFWMD) quickly mobilized deploying crews to collect water quality data as soon as three days after the storm’s passage. Data were collected for several months to evaluate the severity of water quality impacts and determine when pre-storm conditions might return. Despite the passage of Hurricane Nicole in November 2022, dissolved oxygen levels returned to pre-storm conditions within 2-3 months. This was consistent with what was reported in 2004 after Hurricanes Charley, Frances, and Jeanne.

Kayla Hayes, Environmental Specialist, Florida Department of Environmental Protection Aquatic Preserves

“Continuous Water Quality Data in Charlotte Harbor and Matlacha Pass Pre, Mid, & Post Hurricane Ian”

The Florida Department of Environmental Protection (FDEP), Charlotte Harbor Aquatic Preserves’ (CHAP) continuously deployed data sondes captured water quality data before, during, and after Hurricane Ian, which hit the Charlotte Harbor region as a Category 4 storm on September 28th, 2022. Many were damaged or destroyed by Ian. Nonetheless, post-hurricane water quality parameters at MP3C began to resemble pre-hurricane conditions after three weeks.

Dr. Eric Milbrandt, Marine Laboratory Director, Sanibel-Captiva Conservation Foundation

Presentation: “Phytoplankton and Harmful Algal Bloom Dynamics in the Caloosahatchee Estuary and Nearshore Gulf of Mexico” Harmful Algal Blooms (HABs) in Florida have negative effects on the fish and wildlife that depend on healthy coastal ecosystems. The effects are wide ranging, from direct effects of the toxins that HABs produce on fish and wildlife to causing indirect effects such as hypoxia to large areas. People are also affected by HABs, through exposure to the toxins in the water and in the air and by impacting our quality of life and tourism-based economy.

Eric Weather, Research Administrator, Florida Fish and Wildlife Conservation Commission. “FWC’s Fisheries Independent Monitoring Program: An Approach to Understanding Environmental Disturbance Impacts on Florida’s Fisheries”

FWC played a variety of roles assisting with emergency response efforts in the impacted community and for Florida’s fish and wildlife. After ensuring the safety and wellbeing of staff affected by the storm, Fisheries-Independent Monitoring (FIM) biologists resumed sampling efforts as safe access points to the estuary were restored. Despite challenging field conditions, all sampling in October 2022 and beyond was completed. Preliminary analyses of those data indicate that disturbances associated with the passage of hurricane Ian were similar to those observed during previous storms. Overall, while dramatic localized shifts occurred, fish communities stabilized quickly, and estuary-wide impacts were minimal. These results highlight how the historical context provided by the FIM program is essential to understanding the full system-wide effects of natural and anthropogenic disturbances to Florida’s estuarine systems.

Stephanie Erickson, Aquatic Preserve Manager, Estero Bay Aquatic Preserve, “Long Term Trends and Hurricane Impacts on Colonial Wading and Diving Bird Nesting Effort and Islands in Estero Bay”

Estero Bay Aquatic Preserve (EBAP) is the state’s first aquatic preserve, designated in 1966. It is managed by the Florida Department of Environmental Protection- Office of Resilience and Coastal Protection, and includes habitats such as mangroves, intertidal flats, seagrass meadows, and salt marshes. Research continues.

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