The diamondback terrapin (Malaclemys terrapin) is the only resident turtle within brackish water and estuarine systems in the United States (Fig. 1). They prefer coastal estuarine wetlands – living in salt marshes, mangroves, and seagrass communities. The literature suggests they have strong site fidelity – meaning they do not move far from where they live. Within their habitat they feed on shellfish, mollusk and crustaceans mostly. In early spring they will breed. Gravid females will venture along the shores of the bay seeking a high-dry sandy beach where they will lay a clutch of about 10 eggs. She will typically return to lay more than one clutch each season. Nesting will continue through the summer. Hatching begins mid-summer and will extend into the fall. Hatchings that occur in late fall may overwinter within the nest and emerge the following spring. They live 20-25 years.
Fig. 1. The diamondback terrapin. Photo: Molly O’Connor
Terrapins range from Massachusetts to Texas and within this range there are currently seven subspecies recognized – five of these live in Florida, and three are only found in Florida (Fig. 2). However, prior to 2005 their existence in the Florida panhandle was undocumented. The Panhandle Terrapin Project (PTP) was initially created to determine if terrapins did exist here.
Fig. 2. Terrapins of Florida. Image provided by FWC
The Scope of the Project
Phase 1
The project began in 2005 using trained volunteers to survey suitable habitat for presence/absence. Presence is determined by locating potential nesting beaches and searching for evidence of nesting. Nesting begins in April and ends in September – with peak nesting occurring in this area during May and June. The volunteers are trained in March and survey potential beaches from April through July. They search for tracks of nesting females, eggshells of nests that were depredated by predators, and live terrapins – either on the beach or the heads in the water. Often volunteers will conduct 30-minute head counts to determine relative abundance. Between 2005 and 2010 the team was able to verify at least one record in each of the panhandle counties.
Phase 2
The next phase is to determine their status – how many nesting beaches does each county have, and how many terrapins are using them? A suitability map was developed by Dr. Barry Bitters as a Florida Master Naturalist project to locate suitable nesting beaches. Volunteers would visit these during the spring to determine whether nesting was occurring, and the relative abundance was determined using what we called the “Mann Method” – developed by Tom Mann of the Mississippi Department of Wildlife, along with the 30-minute head counts. The Mann Method involved counting the number of tracks and depredated nests within a 16-day window. The assumption to this method was that nesting females would lay multiple clutches each season – but they did not lay more than one every 16 days. Going on another assumption, that the sex ratio within the population was 1:1, each track and depredated nest within a 16-day window was a different female and doubling this number would give the relative abundance of adults in this population. Between 2007 and 2023 we were able to determine the number of nesting beaches in each county and relative abundance in three of those counties (see results below).
Phase 3
Partnering with the U.S. Geological Survey, we were able to move to Phase 3 – which involves trapping and tagging terrapins. Doing this gives the team a better idea of where the terrapins are going and how they are using the habitat. To trap the terrapins, we use modified crab traps (modified so that the terrapins had access to air to breath), seine nets, fyke nets, dip nets, and by hand – the most effective has been modified crab traps (Fig. 3). These traps are placed in terrapin habitat over a 3-day period, being checked daily. Any captured terrapins are measured, weighed, sexed, marked using the notch method, and given a Passive Intergraded Transponder (PIT) tag. Some of the terrapins are given a satellite tag where movement could be tracked by GPS (Fig. 4). We are now bringing on acoustic tagging for some counties. This involves placing acoustic receivers on the bottom of the bay which will detect any terrapin (with an acoustic tag) that swims nearby. Results are below.
Fig. 3. Modified crab traps is one method used to capture adults. Photo: Molly O’Connor
Fig. 4. This tag with an antenna can be detected by a satellite and tracked real time. Photo: USGS
Phase 4
This phase involves collecting tissue samples for genetic analysis. Currently it is believed that the Ornate terrapin (Malaclemys terrapin macrospilota) ranges from Key West to Choctawhatchee Bay, and the Mississippi terrapin (M.t. pileata) ranges from Choctawhatchee Bay to the Louisiana/Texas border. The two subspecies look morphologically different (Fig. 5) and the team believes terrapins resembling the ornate terrapin have been found in Pensacola Bay. Researchers in Alabama have also reported terrapins they believe to be ornate terrapins in their waters as well. The project is now working with a graduate student from the University of West Florida who is genetically analyzing tissue samples from trapped terrapins to determine which subspecies they are and what the correct range of these subspecies. This phase began in 2025, and we do not have any results at this time.
Fig. 5. The Mississippi terrapin found in Pensacola Bay is darker in color than the Ornate terrapin found in other bays of the panhandle. Photo: Rick O’Connor
Ornate Diamondback Terrapins Depend on Coastal Marshes and Sea Grass Habitats Photo: Erik Lovestrand.
2025 UPDATE AND RESULTS
In 2025 we trained 188 volunteers across each county – including state park rangers and members of the Florida Oyster Corps. 47 (25%) participated in at least one survey.
We logged 345 nesting surveys and 17 trap days.
No seining or fyke nets were conducted in 2025.
Phase 1 – Presence/Absence Update
County
Presence
Notes
Baldwin
Yes
A single deceased terrapin was found in western Baldwin County
Escambia
Yes
Team encountered nesting again this year
Santa Rosa
Yes
Two new locations were identified this year
Okaloosa
Yes
Encounters were lower this year
Walton
Yes
FIRST EVIDENCE OF NESTING IN WALTON COUNTY VERIFIED THIS YEAR
Bay
Yes
FIRST EVIDENCE OF NESTING IN BAY COUNTY VERIFIED THIS YEAR
Gulf
Yes
Team encountered nesting again this year
Franklin
ND
ND
Phase 2 Nesting Survey – Update
County
# of primary beaches1
# of secondary beaches2
# of surveys
# of encounters
FOE3
Baldwin
0
TBD
14
04
.00
Escambia
2
35
99
7
.07
Santa Rosa
3
45
137
25
.18
Okaloosa
4
3
20
1
.05
Walton
1
4
28
2
.07
Bay
3
3
47
14
.30
TOTAL
13
17
345
49
.14
1 primary beaches are defined as those where nesting is known to occur.
2 secondary beaches are defined as those where potential nesting is high but has not been confirmed.
3 FOE (Frequency of Encounters) is the number of terrapin encounters / the number of surveys conducted.
4 There was one deceased terrapin found by a tour guide in Baldwin County but was not part of the project.
5 There are potential nesting sites on Pensacola Beach that are technically in Escambia County but covered by the Santa Rosa team. The Escambia team focused on the Perdido Key area.
Phase 3 Trapping/Tagging Update
We currently have 8 years of data.
Terrapins have been tagged in 7 of the 8 panhandle counties.
1483 captures, 1061 individuals.
2025 Capture Effort
Method
County
Number
Description
Condition
Hand capture
Escambia
1
1 adult male
Deceased
Hand capture
Santa Rosa
5
4 adult females
1 unknown
Released, deceased
Hand capture
Okaloosa
1
1 adult female
Released
Dip Net
Santa Rosa
1
1 adult male
Released
Crab Traps
Santa Rosa
34
4 juvenile females
5 adult females
25 adult males
Released
Okaloosa
4
1 juvenile female
3 adult males
Released
TOTAL
46
5 juvenile females
10 adult females
30 adult males
1 unknown
Preliminary information subject to revision. Not for citation or distribution.
Satellite Tagging Information
Due to the size of the tags – only large females are satellite tagged at this time.
Big Momma – tracked for 188 days – averaged 0.16 miles.
Big Bertha – tracked for 137 days – averaged 35.83 miles.
2025 Tracking Effort
County
Tagging Effort
Santa Rosa
2 satellite tagged
6 acoustically tagged
Okaloosa
1 satellite tagged
TOTAL
8 tagged for tracking
Phase 4 Update
This phase began in 2025 and there are no results at this time.
Summary
2025
17 trainings were given in 7 of the 8 counties of the Florida panhandle (including Baldwin County AL).
188 were trained; 47 (25%) conducted at least one survey.
345 surveys were logged; terrapins (or terrapin sign) were encountered 49 (14%) of those surveys.
Every county had at least one encounter during a nesting survey.
17 trapping days were conducted; 46 terrapins were captured; 37 (83%) were captured in modified crab traps; 7 were captured by hand; 1 was captured in a dip net.
8 terrapins were tagged for tracking; 6 acoustically; 2 with satellite tags.
Since 2007
511 have been trained.
1449 surveys have been logged; 347 encounters have occurred; Frequency of Encounters is 24% of the surveys.
Discussion
Phase 1
We have shown that diamondback terrapins do exist in the Florida panhandle and in Baldwin County AL.
Phase 2
We currently have 13 primary nesting beaches we are surveying weekly during nesting season across the panhandle. There were 17 secondary nesting beaches surveyed and most likely there are many more to visit. Nesting seems to be more common in late spring, but the Frequency of Encounters has been declining since 2023. This could be due to less terrapin activity but could also be due to evidence being difficult to find. We will continue to monitor to see how this trend continues.
Phase 3
The team has captured 1483 terrapins, the majority of which were from the eastern panhandle. Satellite tagged females suggest more than one has traveled over 30 miles from where they were tagged. This goes against the idea that terrapins have strong site fidelity. However, all the terrapins tagged were large females (due to size of the tags) so we are looking at the movements of only the larger females – not the population as a whole. The movements of these females also suggest they may use seagrass beds as much as the salt marshes.
Training for volunteers occurs in March of each year. If you are interested in participating, contact Rick O’Connor – roc1@ufl.edu.
The bay scallop (Argopecten irradians) was once common in the lower portions of the Pensacola Bay system. However, by 1970 they were all but gone. Closely associated with seagrass, especially turtle grass (Thalassia testudinum), some suggested the decline was connected to the decline of seagrass beds in this part of the bay. Decline in water quality and overharvesting by humans may have also been a contributor. It was most likely a combination of these factors.
Scalloping is a popular activity in our state. It can be done with a simple mask and snorkel, in relatively shallow water, and is very family friendly. The decline witnessed in the lower Pensacola Bay system was witnessed in other estuaries along Florida’s Gulf coast. Today commercial harvest is banned, and recreational harvest is restricted to specific months and to the Big Bend region of the state. With the improvements in water quality and natural seagrass restoration, it is hoped that the bay scallop may return to lower Pensacola Bay.
Scallop harvest area. Image: Florida Department of Environmental Protection
Since 2015 Florida Sea Grant has held the annual Pensacola Bay Scallop Search. Trained volunteers survey pre-determined grids within Big Lagoon and Santa Rosa Sound. Below is the report for both the 2025 survey and the overall results since 2015.
Methods
Scallop searchers are volunteers trained by Florida Sea Grant. Teams are made up of at least three members. Two snorkel while one is the data recorder. More than three can be on a team. Some pre-determined grids require a boat to access, others can be reached by paddle craft or on foot.
Once on site the volunteers extend a 50-meter transect line that is weighted on each end. Also attached is a white buoy to mark the end of the line. The two snorkelers survey the length of the transect, one on each side, using a 1-meter PVC pipe to determine where the area of the transect ends. This transect thus covers 100m2. The surveyors record the number of live scallops they find within this area, measure the height of the first five found in millimeters using a small caliper, which species of seagrass are within the transect, the percent coverage of the seagrass, whether macroalgae are present or not, and any other notes of interest – such as the presence of scallop shells or scallop predators (such as conchs and blue crabs). Three more transects are conducted within the grid before returning.
The Pensacola Scallop Search occurs during the month of July.
Snorkel transect method. Image: University of Florida.
2025 Results
138 volunteers on 32 teams surveyed 22 of the 66 1-nautical mile grids (36%) between Big Lagoon State Park and Navarre Beach. 162 transects (16,200m2) were surveyed logging 8 scallops. All live scallops were reported from Santa Rosa Sound this year.
2025 Big Lagoon Results
13 teams surveyed 9 of the 11 grids (81%) within Big Lagoon. 76 transects were conducted covering 7,600m2.
No scallops were logged in 2025 though scallop shells were found. No sea urchins were reported but scallop predators – such as conchs, blue crabs, and rays were. This equates to 0.00 scallops/200m2 and moves Big Lagoon from a vulnerable system last year to a collapsed one this year. All three species of seagrass were found (Thalassia, Halodule, and Syringodium). Seagrass densities ranged from 50-100%. Macroalgae was present in 5 of the 9 grids (56%) and was reported abundant in grid 2.
2025 Santa Rosa Sound Results
19 teams surveyed 13 of the 55 grids (23%) in Santa Rosa Sound. 86 transects were conducted, covering 8,600m2.
8 scallops were logged which equates to 0.19 scallops/200m2. Scallop searchers reported blue crabs, conchs, and rays. All three species of seagrass were found. Seagrass densities ranged from 5-100%. Macroalgae was present in 7 of the 13 grids (54%) and was reported as abundant in 4 of those.
2015 – 2025 Big Lagoon Results
Year
No. of Transects
No. of Scallops
Scallops/200m2
2015
33
0
0.00
2016
47
0
0.00
2017
16
0
0.00
2018
28
0
0.00
2019
17
0
0.00
2020
16
1
0.12
2021
18
0
0.00
2022
38
0
0.00
2023
43
2
0.09
2024
67
101
3.02
2025
76
0
0.00
Big Lagoon Overall
399
104
0.52
2015 – 2025 Santa Rosa Sound Results
Year
No. of Transects
No. of Scallops
Scallops/200m2
2015
01
0
0.00
2016
01
0
0.00
2017
01
0
0.00
2018
01
0
0.00
2019
01
0
0.00
2020
01
0
0.00
2021
20
0
0.00
2022
40
2
0.11
2023
28
2
0.14
2024
85
32
0.76
2025
86
8
0.19
Santa Rosa Sound Overall
2591
44
0.34
1Transects were conducted during these years but data for Santa Rosa Sound was logged by an intern with the Santa Rosa County Extension Office and is currently unavailable.
Discussion
Based on a Florida Fish and Wildlife Research Institute publication in 2018, the final criteria are used to classify scallop populations in Florida.
Scallop Population / 200m2
Classification
0-2
Collapsed
2-20
Vulnerable
20-200
Stable
Based on this, over the last nine years we have surveyed, the populations in lower Pensacola Bay are still collapsed. Big Lagoon reached the vulnerable level in 2024, but no scallops were found there in 2025, returning to a collapsed state.
There are some possible explanations for low numbers in 2025.
It has been reported by some shellfish biologists that bay scallops have a “boom-bust” cycle. Meaning that one year their populations “boom” before returning to normal numbers. We could have witnessed this between 2024 and 2025.
Though we did not monitor water temperatures, July 2025 was extremely hot, and many volunteers reported their sites felt like “bath water”. Collecting efforts on other projects during July reported not capturing anything – no pinfish, hermit crabs – their nets were empty. It is possible that these warm conditions could have caused many organisms to move to deeper/cooler depths. Note here; as the project moved into August temperatures did begin to cool and searchers began reporting fish, conchs, blue crabs, and rays.
The Pensacola Bay area continues to have a collapsed system. The larger populations found in 2024 suggest that there are scallops in the area but may not be enough to increase their population status from collapsed to vulnerable. We will continue to monitor each July.
It is important for locals NOT to harvest scallops from either body of water. First, it is illegal. Second, any chance of recovering this lost population will be lost if the adult population densities are not high enough for reproductive success.
Acknowledgements
We would like to thank ALL 138 volunteers who surveyed this year. We obviously could not have done this without you.
Below are the “team captains”.
Ethan Sadowski John Imhof Kaden Luttermoser
John Wooten Susan Pinard Matt MacGregor
Christian Wagley Sean Hickey Jason Buck
Brian Mitchell Angela Guttman Caitlen Murrell
Samantha Brady (USM) Michelle Noa Kira Benton
Monica Hines Wesley Allen Kelly Krueger
Mikala Drees Jonathan Borowski Michael Currey
Gina Hertz Melinda Thoms Beau Vignes
Bill Garner Robert Moreland Stephanie Kissoon
Nick Roest Leah Yelverton
A team of scallop searchers celebrates after finding a few scallops in Pensacola Bay.
Volunteer measures a scallop he found. Photo: Abby Nonnenmacher
A blue bowl filled with bay scallop linguini in a white wine garlic sauce.
I love harvesting and eating local Bay scallops. Port St. Joe Bay is the scalloping area closest to Walton County. These tasty mollusks live in sea grass beds in shallow water. This makes them easy to find simply snorkeling, on a paddle board, kayak or from a boat.
Scallops used to be plentiful in all our Bays, including the Choctawhatchee Bay. These shellfish, however, are sensitive to environmental changes and due to their relatively short lifespan, are susceptible to periodic collapses. To enjoy recreational scalloping for years to come, it is important that safety and conservation stay top of mind. Following the best practices below will ensure the bay scallop fishery is protected for future generations to enjoy.
Throw back small scallops. Recreational harvest occurs before scallops are given the chance to reproduce. Smaller ones are younger than older and have a higher chance of living to reproduce in the fall and possibly again in the winter. In Florida, scallops typically live for about 18 months. While it is not legally required, throwing back small scallops (those less than 2 inches) is a great way to do your part to protect the fishery. Also, small scallops have smaller muscle meat so it might not even be worth your while to shuck the small ones.
Keep only what you will eat. While “limiting out” might seem like an obvious goal, don’t forget that someone will have to shuck all those scallops! One pint of scallop meat (the typical daily limit for one person) is roughly four servings of scallops. Rather than setting a goal of catching your limit, consider setting a more conservative goal based on how much meat you will eat. Scallop meat only keeps in the fridge for 1 day or about 3 months frozen. Plan accordingly!
Never double dip. Locals and law enforcement officers in the bay scallop harvest areas often report “double dipping”, or scallopers going out for a second trip after landing one limit. Without question, this is illegal. But is is also highly unethical and shows disrespect for the fishery and the people with livelihoods that depend on bay scallops.
Protect seagrass when boating. Be aware of seagrasses while boating in shallow areas! Many species, including bay scallops, depend on seagrasses. Damage from propellers and boat anchors (called seagrass scarring) reduces habitat quality and resilience of seagrasses over the long-term. Please visit the Be Seagrass Safe website for more information
Discard shells responsibly. Shells and soft tissues should be disposed of in open Gulf of Mexico waters with moderate to strong currents that are not channels, canals, marinas, springs, or boat ramps. Shells and soft tissues can cause problems for water quality and boating when dumped in high traffic areas close to shore. Shells disposed of in shallow swimming areas, such as springs or sandbars, pose a serious hazard to swimmers. If you clean your catch on shore, dispose of shells/soft tissues in the trash or clean and re-use for crafts or landscaping around the house.
When I began working with terrapins 20 years ago, very few people in the Florida panhandle knew what they were – unless they had moved here from the Mid-Atlantic states. Since we initiated the Panhandle Terrapin Project in 2005 many more now have heard of this brackish water turtle.
Ornate Diamondback Terrapin (photo: Dr. John Himes)
Diamondback terrapins are relatively small (10 inch) turtles that inhabit brackish environments such as salt marshes along our bays, bayous, and lagoons. They have light colored skin, often white, and raised concentric rings on the scales of their shells which give them a “diamond-backed” appearance. Some of them have dark shells, others will have orange spots on their shells.
The first objective for the project was to determine whether terrapins existed here, there was no scientific literature that suggested they did. We found our first terrapin in 2007, and this was in Santa Rosa County. We have since had at least one verified record in every panhandle county – diamondback terrapins do exist here.
The second objective was to locate their nesting beaches. Terrapins live in coastal wetlands but need high-dry sandy beaches to lay their eggs. Volunteers began searching for such and have been able to locate nesting beaches in Escambia, Santa Rosa, Okaloosa, Bay, and Gulf counties. We continue to search in the other counties, and for additional ones in the counties mentioned above. Once a nesting beach has been identified, volunteers conduct weekly nesting surveys, providing data which can help calculate the relative abundance of terrapins in the area.
Tracks of a diamondback terrapin. Photo: Terry Taylor
The third objective is to tag captured terrapins to determine their population, where they move and how they use habitat. We initially captured terrapins using modified traps and marking them using a file notching system. We then partnered with a research team from the U.S. Geological Survey and now include passive integrated transponder tags (PIT tags) that help identify individuals, satellite tags that can be detected from satellites and track their movements, and recently acoustic tags which can also track movement.
The fourth objective is to collect tissue samples for genetic studies. This information will be used to help determine which subspecies of terrapins are living in the Florida panhandle.
As we move into the summer season, more people will be recreating in our bays and coastal waterways. If you happen to see a terrapin, or maybe small turtle tracks on the beach, we would like you to contact us and let us know. You can contact me at roc1@ufl.edu. Terrapins are protected in Florida and Alabama, so you are not allowed to keep them. If you are interested in joining our volunteer team, contact me at the email address provided.
The North American Coastal Plain. Diagram courtesy Musa Jundi, UF Biodiversity Institute.
According to Conservation International, there are 36 biodiversity hotspots worldwide. These are defined as areas with “at least 1,500 vascular plants as endemics — which is to say, it must have a high percentage of plant life found nowhere else on the planet. A hotspot, in other words, is irreplaceable. It must have 30% or less of its original natural vegetation. In other words, it must be threatened.”
An exhibit at the Biophilia Center in Walton County highlights the biodiversity of our region. Photo credit: Carrie Stevenson, UF IFAS Extension
Only two of these 36 biodiversity hotspots lie within the United States, including the North American Coastal Plain, which stretches from Texas along the Gulf Coast and up the Atlantic coast. The state of Florida rests fully within the coastal plain. Within that region, northwest Florida is the hottest “biodiversity hotspot,” one of just six designated regions in North America.
Why us? How did our little corner of the state earn such notoriety? If you’ve ever spent August here, you know how very hot and humid it gets in the summer. As we experienced with the snow and freeze a couple of weeks ago, the Panhandle endures some rather extreme temperatures that fall within our natural range. Our coastal communities sit just above sea level, but we’ve also got hills—while not terribly high (345 feet), the state’s highest point is in Walton County. Along the bluffs of the Apalachicola are whispers of the last Ice Age, where fingers of the Appalachian Mountain range are visible in the same hardwood species and geologic formations typical of north Georgia and Tennessee.
Florida Master Naturalist students visit Britton Hill, the highest point in Florida. Photo credit: Carrie Stevenson, UF IFAS Extension
As they say, variety is the spice of life, and this wide spectrum of livable habitats, from coastal marsh to high and dry ridges means we have more options for plants and wildlife to inhabit. The Florida panhandle is home to more than 2500 plant species, 300 species of birds, and 25 species of salamanders, including many endemic species found nowhere else in the world. The oxygen-deprived soils of our flatwood bogs give rise to dozens of carnivorous plant species. They’ve adapted to poor nutrition in the soil by supplementing with insects. Vast waterways mean we have 500 species of saltwater fish and at least 85-90 freshwater fish, including those that live a portion of their life cycle in both.
In the wild world of pitcher plant bogs, frogs compete with plants for insect prey. Photo credit: UF IFAS Extension
A project known as the Northwest Florida Greenway Corridor is actively being funded and set aside to create a 150,000 acre conservation region connecting two million acres of protected land including Blackwater River State Forest, Eglin Air Force Base, and Apalachicola National Forest . Along with coastal barrier islands and inland areas of Gulf Islands National Seashore, these huge swaths of land enable large species like bears, alligators, and cats to roam with less interference from human development. Restoration of longleaf pine and dune ecosystems mean the land and waters are managed to ensure the survival of smaller endangered species like flatwoods salamanders, beach mice, gopher tortoises, red cockaded woodpeckers, and sea turtles. The confluence of less development (compared with densely urban areas to our south), large state and national parks, and protected military bases have allowed plants and wildlife to thrive unlike any other region.
The presence of dragonfly larvae is a sign of good water quality. Photo credit: UF IFAS Extension
In science, we measure both species richness (the number of different species in an area) and abundance (actual number of individuals) to come up with an index for species diversity. Generally, the higher these numbers, the healthier the ecosystem. A clear example of this can be seen when monitoring water quality in streams. If you sample the macroinvertebrate population of a creek and find only bloodworms, you know water quality conditions are terrible. These species can survive in sewage water. But, if you find dozens of species, particularly the larvae of pollution-sensitive caddisflies, mayflies, and stoneflies, this indicates the water is clean and hospitable to a wide variety of species. These insects serve as the basis of the food web for fish, crabs, and larger animals that maintain a healthy ecosystem.
The layered canopies of trees with diverse fruit and flowers provide habitat for thousands of bird, reptile, mammal, amphibian, and insect species, making it the most biodiverse habitat type on the planet. Photo courtesy Manuel Antonio National Park, Costa Rica.
It’s generally understood in ecology that the “higher the diversity, the greater the stability.” When we create monocultures—ecosystems containing one or only a handful of dominant species types—these systems are weak and susceptible to attack. Agricultural operations that grow one crop are prime examples of how monocultures can be highly vulnerable—orange groves devastated by disease or freezes; chicken farms wiped out by avian influenza. They cannot adapt to threats, and being genetically similar they can be easily devastated by a single disease or environmental threat. Having a diversity of species creates a redundant “back-up” system for crucial ecosystem services, like providing pollen, erosion management, or shade from extreme heat if other species suffer from pathogens or parasites.
Agriculturists recommend rotating crops annually or seasonally to increase soil health and prevent the weaknesses brought on by monocultures. Photo credit: Ann Blount, UF IFAS Extension
Just like economists measure the health of an economy by productivity, ecologists can analyze ecosystems mathematically. And where are those most productive ecosystems located? It’s not the extreme habitats of tundra, grassland, and desert, where only a handful of species survive. The most productive ecosystems—those cycling nutrients, producing oxygen, and converting solar energy to biomass, are the most diverse ones. At the top are tropical rainforests, coral reefs, and estuarine swamps and marshes. These ecosystems have thousands of moving parts and are virtually impenetrable to a single disease or pest wiping them out. If one species suffers, there are so many backups to fill in and perform the important roles. In fact, the only disturbance any of these systems can’t defend against are complete clearing or extreme pollution by humans.
The world is much bigger than humanity. It is wise to consider the words of my favorite biologist, E.O. Wilson. An expert on insects, especially ants, he once said, “If all mankind were to disappear, the world would regenerate back to the rich state of equilibrium that existed ten thousand years ago. If insects were to vanish, the environment would collapse into chaos.”
With this article we will shift from the microscopic creatures of the Gulf of Mexico to the macroscopic ones – ones you can see without a microscope. We will begin with the simplest and most primitive of macroscopic creatures – the seaweeds.
Many locals see the grass washed ashore along the Intracoastal Waterway and call this seaweed, but it is in fact seagrass. Seaweed differs from seagrass in that they are not true plants. True plants are vascular – meaning they have a series of “veins” running through their body called xylem and phloem. These veins move water and material throughout the body – similar to the arteries and veins of an animal. But seaweeds lack this “circulatory” system, rather they absorb water through their tissues and must live in the water environment to do this. Seaweeds lack leaves, stems, and roots. They do not produce seeds or flowers, but they do require sunlight and nutrients and conduct photosynthesis as true plants do. When I was in college seaweed was considered simple plants – just nonvascular ones. Today biologists believe they are too simple to be considered plants and thus are a group existing between the microscopic phytoplankton and the true vascular plants we know from our lawns and forests. They are often called algae as well as seaweed.
Mats of Sargassum on a south Florida Beach. Photo: University of Florida
Biologists divided the seaweeds into divisions based on their color, which is determined by the photosynthetic pigments they have for photosynthesis. Compared to my college days, the classification of green algae is quite complex. The entire group was once placed in the Division Chlorophyta. Today, most sources consider only the marine forms of green algae in the group Chlorophyta, with numerous other groups consisting of thousands of species. Most green algae live in freshwater and are believed to be the group that led to the land plants we are familiar with. Their photosynthetic pigments include chlorophyll and a and b but also carotene and xanthophyll. The pigments are dominated by the chlorophylls – hence their green color – and the ratio of chlorophyll to carotene and xanthophyll is the same as the plants you find in your yard – hence the argument they led to the evolution of land plants.
Green algae – or any of the seaweeds – are not as common along the northern Gulf of Mexico as you find on other coasts. Not having true roots, stems, or leaves, seaweeds must attach themselves to the seafloor using a suction cup type structure called a holdfast. To attach, the holdfast must have a rock of some type. Along the rocky shores of Maine and California, they are quite common. Even with the limestone rock of south Florida you can find these. But the fine quartz sand of the northern Gulf of Mexico is not as inviting to them. That said, we do find them here and most are found on man-made structures such as jetties, seawalls, and artificial reefs – I found one attached to a beer can.
Of all of the green algae that exist in Florida, I have only encountered three. One is called “sea lettuce” in the genus Ulva. Attached to rock jetties and seawalls, it looks just like lettuce and is beautiful, brilliant green in color. It grows to about seven inches in height and is used as a food source in different countries. It can become a problem if local waters are high in nutrients due to pollution from land sources. It will grow abundantly, reducing habitat for other species, and wash ashore during storms where it breaks down releasing gases that can be toxic to shore life and humans. I first encountered it growing on the rock jetties at St. Andrews State Park in Panama City, but it does grow on local hard structures.
Sea Lettuce. Photo: University of California
“Dead Man’s Fingers” – Codium – is another green algae I first encountered it on the jetties of St. Andrews. The thick finger-like projections of this seaweed extending from the rocks did resemble a glove – or the fingers of a dead man within the rocks. Some species around the world are used for food. But I could not find any references that it is here.
“Deadman’s Fingers”. Photo: iNaturalist
The third species of green algae I have seen locally is known as the “Mermaids Wine Glass” – Acetabularia. This beautiful seaweed is relatively small and does resemble a wine, or martini glass. They are quite abundant in south Florida and is the one I found growing on a beer can submerged in Santa Rosa Sound.
“Mermaid’s Wineglass” Photo: Project Noah
Though seaweeds in general are harder to find along the northern Gulf coast, they are fun to search for and do play a role as primary producers here.
