Bay scallops (Argopecten irradians) have been an important part of the economy of many gulf coast communities within the Florida Big Bend for decades. It was once abundant in all gulf coast counties of the state but beginning in the 1960s populations in many bays began to decline to levels where they are all but nonexistent. The cause of this decline has been associated with many factors including a decline in water quality, a decline in suitable habitat (sea turtle grass beds – Thalassia), and overharvesting. Most likely the cause included all of these. Since the collapse of both the commercial and recreational fishery, Gulf coast communities have been trying to address all three of the stressors above. Multiple monitoring projects are ongoing in the Pensacola Bay area and one of those is the Great Scallop Search.
The Great Scallop Search was developed by Sea Grant Agents in Southwest Florida and expanded, through Florida Sea Grant, to Northwest Florida. In each location volunteers snorkel a 50-meter transect line searching for live bay scallops, as well as monitoring the status of the seagrass habitat. Since 2015 317 volunteers have logged 634 hours surveying 407 50-meter transects in 106 grids in Big Lagoon or Santa Rosa Sound. In that time 4 live scallops have been logged, though we hear anecdotal reports of additional scallops being found in these bodies of water.
Survey Method
Volunteers select and survey one of 11 grids in Big Lagoon, or one of 55 grids in Santa Rosa Sound. Once on site, the volunteers anchor and record preliminary information on the data sheet provided. Two snorkelers enter the water and swim on opposite sides of a 50-meter transect line searching for live scallops. Any live scallop found is measured and returned. The species and density of the seagrass is recorded as well as the presence/absence of macroalgae on that seagrass. Four such transects are surveyed in each grid.
2023 Results
2023
SRS
BL
Total
Other
# of volunteers
72
No significant difference between 2022 and 2023
# of grids surveyed
8
8
16
Slight decrease from 2022. 16 of the 66 grids (24%) were surveyed.
# of transects surveyed
26
51
77
A decrease from 2022. More surveys were conducted in Big Lagoon than Santa Rosa Sound.
Area surveyed (m2)
2600
5100
7700
1.9 acres
# of scallop found
2
2
4
Four live scallops are a record for this project. It equals the sum of all other live scallops since the project began.
Scallop Size (cm)
4.5, 5.0
4.0, 4.5
Surveys with Seagrass
Halodule
5
12
17
17/21 surveys – 81%
Thalassia
8
11
19
19/21 surveys – 90%
Syringodium
0
2
2
2/21 surveys – 10%
Grass Density
100% grass
3
9
12
12/21 surveys (57%) were 100% grass
90%
1
0
1
Note: Volunteers typically select area for transects
75%
3
1
4
with a lot of grass.
70%
1
0
1
50%
3
9
12
5%
1
0
1
Macroalgae
Present
4
4
8
Absent
2
10
12
12/21 surveys (57%) had no macroalgae.
Abundant
2
2
4
Sediment Type
Mud
0
1
1
Sand
7
8
15
15/21 surveys (71%) were sandy.
Mixed
1
4
5
21 surveys were conducted covering 16 grids. 8 grids were surveyed in each body of water.
A total of 77 transects were conducted covering 7,700 m2 and four live scallops were found.
Two of the scallops were found in Big Lagoon and two in Santa Rosa Sound.
All scallops measured between 4-5cm (1.6-2”).
The number of live scallops found this year equaled the total number found over the last eight years.
Most of the transects included a mix of Halodule and Thalassia seagrass ranging from 100% coverage to 5%. The majority of the transects were between 50-100% grass. Four transects had 100% Thalassia. Three of those were in Santa Rosa Sound, one was in Big Lagoon. The diving depth of the volunteers ranged from 0 meters (0 feet) to 2.4 meters (8 feet). Macroalgae was present in 8 of the 21 surveys (38%) but was not abundant in most.
Volunteer measuring one of the four collected bay scallops in 2023 from Pensacola Bay.
Photo: Gina Hertz.
Summary of Project
Year
Volunteer
Grids Surveyed
Transects Surveyed
Live Scallops Found
2015
87
28
101
0
2016
96
31
111
1
2017
5
4
16
0
2018
20
7
32
0
2019
13
6
20
0
2020
5
2
16
1
2021
17
6
24
0
2022
74
22
87
2
2023
72
16
77
4
TOTAL
317
407
8
MEAN
35
14
45
0.4
To date we are averaging 35 volunteers each event, surveying 14 of the 55 possible grids (25%). We are averaging 45 transects each year (4500 m2), have logged 407 transects (40,700 m2) and have recorded 8 live scallops (< than one a year).
Discussion
Based on the results since 2016 this year was a record year for live scallops. Whether they are coming back on their own is still to be seen. Being mass spawners, bay scallop need high densities in order to reproduce successfully, and these numbers do not support that. The data, and comments from volunteers, suggest that the grasses look good and dense. Thalassia, a favorite of the bay scallop, appear to be becoming more abundant. This is a good sign.
Though small and few, bay scallops are trying to hold on in Pensacola Bay.
Photo: Gina Hertz
October is Dune Lake Awareness month and as part of the celebration, Walton and Okaloosa County UF/IFAS Extension Agents are joining together to host a Coastal Dune Lake Tour at Western Lake in Grayton Beach State Park. This free event will include a brief lecture and guided tour of the nature trail surrounding the lake. Laura Tiu, Marine Science Agent, will start the tour with a history of the lakes, the unique ecology and some of the local protections. Sheila Dunning, Horticulture Agent, will share information on the unique flora in the dunes including which plants have been used by native Americans and pioneers for food and medicine and the trees we find in the dune landscape surrounding the dune lakes and their adaptations to this sometimes-harsh environment. If you have an interest in our local dune lakes or the tour, you may visit the Walton County Dune Lake website at https://www.co.walton.fl.us/97/Coastal-Dune-Lakes. If you would like to register for this free tour go to https://www.eventbrite.com/e/panhandle-outdoor-live-2023-coastal-dune-lake-lecture-and-trail-tour-tickets-722764316527?aff=oddtdtcreator or use our Facebook event link https://www.facebook.com/events/811943803961304. Feel free to call our office, 850-892-8172, with any questions.
Miami is ground zero for invasive species in this state. But the Florida panhandle is no stranger to them. Where they are dealing with Burmese pythons, melaleuca, and who knows how many different species of lizards – we deal with Chinese tallow, Japanese climbing fern, and lionfish. The state spends hundreds of thousands of dollars each year battling and managing these non-native problem species. By definition, invasive species cause environmental and/or economic problems, and those problems will only get worse if we do not spend the money to manage them. Those who work in invasive science and resource management know that the most effective way to manage these species is to detect them early and respond rapidly.
The Invasive Species Curve
Invasive species have made their way to the coastal waters and dunes of the barrier islands in the Florida panhandle. Beach vitex, Brown anoles, and Chinese tallow are found on most. Recently on Perdido Key near Pensacola, we found a new one – cogongrass.
Cogongrass (Imperata cylindrica) was accidentally introduced to the Gulf coast via crates of satsumas entering the port of Mobile in 1912. It began to spread from there and has covered much of the upland areas of the southeastern U.S. It has created large problems within pasture lands, where livestock will not graze on it, and in pine forest where it has decreased plant and animal biodiversity as well as made prescribed burning a problem – it burns hot, hot enough to actually kill the trees. The impacts and management of this plant in that part of the panhandle has been known for a long time. The Department of Agriculture lists it as one of the most invasive and noxious weeds in the country.
Cogongrass seedheads are easily spotted in spring.
Photo credit: Mark Mauldin
Two years ago cogongrass was discovered growing around a swimming pool area at a condo on Perdido Key. To be considered an invasive species you must (a) be non-native to the area – cogongrass is certainly non-native to our barrier islands, (b) have been introduced by humans (accidentally or intentionally) – strike two, we THINK it was introduced by mowers. This is a common method of spreading cogongrass, mowing an area where it exists, then moving those mowers to new locations without cleaning the equipment. We do not know this is how it got to the island, but the probability is high. Third, it has to be causing an environmental and/or economic problem. It certainly is north of the I-10, but it is not known what issue it may cause on our barrier islands. Could it negatively impact protected beach mice and nesting sea turtle habitat? Could alter the integrity of dunes to reduce their ability to hold sand and protect properties. Could it overtake dune plants lowering both plant and animal diversity thus altering the ecology of the barrier island itself? We do not know. What we do know is that if we want to eradicate it, we need to detect it early and respond rapidly.
According to EDDMapS.org – there are 75 records of cogongrass on the barrier islands, and coastal beaches of the Florida panhandle. This is most likely under reported. So, step one would be to conduct surveys along your islands and beaches. Florida Sea Grant and Escambia County of Marine Resources are doing just that. EDDMaps reports five records on Perdido Key and four at Ft. Pickens. It most likely there is more. A survey of the northeast area of Pensacola Beach (from Casino Beach east and north of Via De Luna Drive) has found two verified records and two unverified (they are on private property, and we cannot approach to verify). Surveys of both islands continue.
The best time to remove/treat cogongrass is in the fall. The key to controlling this plant is destroying the extensive rhizome system. In the upland regions, simple disking has been shown to be effective if you dig during the dry season, when the rhizomes can dry out, and if you disk deep enough to get all of the rhizomes. Though the rhizomes can be found as deep as four feet, most are within six inches and at least a six-inch disking is recommended. Depending on the property, this may not be an option on our barrier islands. But if you have a small patch in your yard, you might be able to dig much of it up.
Chemical treatments have had some success. Prometon (Pramitol), tebuthurion (Spike), and imazapyr have all had some success along roadsides and in ditches north of I-10. However, the strength of these chemicals will impede new growth, or plantings of new plants, for up to six months. There are plants that are protected on our islands and on Perdido Key any altering of beach mouse habitat is illegal. We certainly do not want to kill plants that are holding our dunes. If you feel chemical treatment may be needed for your property, contact the county extension office for advice.
Most recommend a mixture of burning, disking, and chemical treatment. But again, this is not realistic for barrier islands. Any mechanical removal should be conducted in the summer to remove thatch and all older and dead cogongrass. As new shoots emerge in late summer and early fall herbicides can then be used to kill the young plants. Studies and practice have found complete eradication is difficult. It is also recommended not to attempt any management while in seed (in spring). Tractors, mowers, etc. can collect the seeds and, when the mowers are moved to new locations, spread the problem. If all mowing/disking equipment can be cleaned after treatment – this is highly recommended.
Step one would be to determine if you have cogongrass on your property, then seek advice on how to best manage it. For more information on this species, contact your local extension office.
A deer darting across a path, a bobwhite calling at sunrise, or the tracks of a coyote in the mud are all fascinating examples of how we enjoy our natural areas. Have you ever wished you could watch wildlife all day to understand the intricate relationships they have with one another? What if you could learn more about their behavior? And their habitat and daily activities?
Deer captured on a digital game camera.
Image: Dr. Carolina Barzzui.
Dr. Carolina Baruzzi at the UF/IFAS North Florida Research and Education Center and Dr. Corey Callaghan at the UF/IFAS Fort Lauderdale Research and Education Center are launching “ConservationCam”, a new extension program to help you monitor wildlife on your property using camera traps.
Camera traps are a valuable tool for wildlife monitoring. When an animal moves in front of a camera, they trigger a motion sensor to take a picture or video. Camera traps can be set up in multiple ways to target a species or habitat of interest, such as a forest opening or a wildlife burrow. Thanks to their versatility and relative low cost, camera traps are being used in a variety of contexts, for example, understanding the effects of wildlife or habitat management on target species.
Images of turkeys captured on a digital game cam.
Image: Dr. Carolina Barzzui.
The primary goal of ConservationCam is to provide private landowners with access to camera traps, and expert guidance about monitoring wildlife and managing natural resources for biodiversity based on camera trap observations. Armed with this knowledge, landowners can make informed decisions about land management practices that positively impact biodiversity on their property. If you live in the Florida Panhandle, and are interested in using camera traps to monitor wildlife on your property, while learning how to answer different ecological questions, we are gathering expressions of interest through this online form.
Rabbit near a burrow on a digital game came.
Image: Dr. Carolina Barzzui.
Discover the fascinating world of Cuban Treefrogs and join us for an exciting workshop aimed at effectively managing their invasion. Led by Dr. Steve Johnson, an expert on Cuban Treefrogs from UF/IFAS Extension, this workshop will provide you with valuable insights on recognizing these invasive frogs and exploring management options. In addition, attendees will have the opportunity to learn how to monitor and report data on Cuban Treefrog populations. Together, let’s take action to address the challenges posed by the invasion of Cuban Treefrogs! The Workshop will be held September 28th 9am – 3pm CDT at 2728 E14th St, Panama City, FL 32401Register Here
The Invasion of Cuban Treefrogs:
Originating from Cuba and introduced unintentionally to Florida in the 1920s, the Cuban Treefrog has rapidly established itself across various states, including Georgia and Louisiana. Believed to have arrived as stowaways in shipping crates, these non-native frogs have become a cause for concern due to their impacts on native treefrog and toad populations.
Understanding the Threat:
Cuban Treefrog adults and their tadpoles are known predators of native treefrogs and toads. Their presence poses a significant threat to the delicate balance of our ecosystems. Therefore, it is crucial to develop effective management strategies to curb their invasion and minimize their impact on our native species.
Workshop Highlights:
During the workshop, Dr. Steve Johnson, an esteemed authority on Cuban Treefrogs, will guide participants through the identification and management of these invasive frogs. Attendees will gain valuable knowledge and practical skills to recognize Cuban Treefrogs and explore options for effectively managing their populations. Participants will also build and take home their own treefrog house (refugia) made with PVC.
Contributing to Research:
In addition to learning about identification and management, workshop attendees will have the opportunity to play an active role in monitoring and reporting data on Cuban Treefrog populations. By actively participating in data collection efforts, you will contribute to scientific research and provide crucial insights into the distribution and behavior of these invasive frogs.
Join the Cause:
The invasion of Cuban Treefrogs is a pressing environmental issue that requires collective action. By attending our workshop, you can become an agent of change in addressing this invasive species. Let’s work together to protect our native treefrogs and toads by effectively managing the population of Cuban Treefrogs.
Don’t miss out on this unique opportunity to join Dr. Steve Johnson and fellow nature enthusiasts in our workshop focused on managing the invasion of Cuban Treefrogs. By acquiring knowledge, developing practical skills, and contributing to data collection efforts, you can actively participate in protecting our native species and preserving the delicate balance of our ecosystems. Together, let’s make a difference and tackle the challenges posed by the Cuban Treefrog invasion. Register now and be a part of this important environmental initiative!
An invasive Cuban Tree Frog specimen. Invasive species, amphibians and reptiles. frogs, pests. UF/IFAS Photo by Tyler Jones.
There is a term that all oyster farmers dislike, it is almost like that one villain from a famous book/movie series where they shouldn’t say his name. That term is “unexplained spring/summer mortality” and it has been a growing issue along with the expansion of oyster farming throughout the southeast. While the art of oyster farming has been around since the time of the Romans, it is a relatively new venture here in the Gulf of Mexico, and Florida is home to over one hundred oyster farms. These farms are meticulously cared for by the oyster farm crew, with many different anti-fouling techniques and biosecurity measures in practice to provide the customer with a safe, clean product that you can consume even in the months without an R (another article on that coming later). Each year, farm managers can expect a 10-30% mortality event during the transition from winter into spring/summer, hence the term “unexplained spring/summer mortality.” Researchers and scientists from all over the southeast have been actively working to find a cause for this phenomenon, but the answer has been hard to find.
Dead, market ready oysters from one bag. Cause of death, “Unexplained Mortality Event 2022” Photo by: Thomas Derbes II
Our Pensacola Bay has been a hotbed for oysters lately; The Nature Conservancy recently constructed 33 oyster beds along Escribano Point in East Bay, the establishment of the Pensacola & Perdido Bay Estuary Program, acquisition of a $23 million restoration grant with $ 10 million towards 1,482 acres of oyster restoration, and the establishment of oyster farms and hatcheries. In Pensacola Bay, there are currently 5 oyster farms in operation, one of those farms being a family-owned and operated Grayson Bay Oyster Company. Brandon Smith has been managing the business and farm for over 4 years now and has experienced mortality events during those prime spring/summer months. In recent years, they have experienced mortality events ranging from minimal to what many would consider “catastrophic,” and reports from around Florida and the Southeast convey a similar message. Concerned for not only the future of his family farm, but other oyster farms in the Southeast, he has been working with the most experienced institutions and groups in 2022 to possibly get an answer on his and other local “unexplained mortality events.” Each road led to the same answer of “we aren’t quite sure,” but this didn’t deter Smith or other the farmers who are dealing with similar issues.
In 2023, Smith was invited to participate in a Florida-Wide program to track water quality on their farm. This project, led by Florida Sea Grant’s Leslie Sturmer from the Nature Coast Biological Station in Cedar Key, Florida, hopes to shed some light on the changes in water quality during the transition from winter to spring and spring to summer. Water samples have also been taken weekly to preserve plankton abundance and the presence of any harmful algae if a mortality event does occur. With the hottest July on record occurring in 2023, temperature could play a role in mortality events, and now researchers are equipped with the right tools and open lines of communication to possibly find a solution to the problem.
3-month-old seed being deployed out on Grayson Bay Oyster Company’s farm in Pensacola, Florida (2023). Photo by: Thomas Derbes II
As with traditional farming on land, oyster farming takes a mentally strong individual with an incredible work ethic and the ability to adapt to change. The Southeast has a resilient system of oyster farmers who display these traits and continue to put their noses down and “plant” seed every year for the continuation of a growing yet small industry, even through the hardest of trials and tribulations. Through collaboration with local and state institutions, stakeholders, programs, and citizens, oyster farmers are hopeful that they can solve this “unexplained mortality event” and help develop resilient farming techniques. An important message is local farms that have environmental and economic impacts cannot exist without the support of their community.
If you’re interested in tracking water quality on select farms, including Grayson Bay Oyster Company, the website is https://shellfish.ifas.ufl.edu/farms-2023/ and it is updated monthly.
