When you sit down and enjoy some fresh, farmed oysters during the summer, you might notice that the oyster is not watery but yet plump and full of meat, unlike the usual wild oysters. These farmed oysters are very special and are called “triploid oysters.” What makes an oyster a triploid? Well, it all starts in the oyster hatchery and involves using tetraploid male oysters to breed with diploid female “wild” oysters.
Before we dive into triploids, let’s go over some definitions. A diploid organism contains two sets of chromosomes. As humans, we have two sets of chromosomes, and the pair is formed by a chromosome from the mother and a chromosome from the father. Triploid organisms contain three sets of chromosomes and while very rare, triploidy does happen in the wild. Tetraploid organisms have four sets of chromosomes and are usually only formed in a laboratory setting using pressure or other means to cause tetraploidy. When you breed a tetraploid oyster with a diploid oyster, the result is a triploid oyster.
A hatchery worker keeping an eye on spawning chambers with diploid oysters – Thomas Derbes II
Inside of an oyster hatchery, you will see many small breeding chambers for the oysters. When a hatchery decides to spawn oysters, they place a single wild diploid oyster in each chamber. During spawning, the hatchery will introduce a cycle of cold then warm water and this cycle is repeated until a spawn is triggered. Hatchery workers will closely watch the oysters and will shut off the water supply to any oyster that has spawned so they can trap the gametes in the chamber. You can determine the sex of an oyster by watching it spawn; a female oyster “claps” out her eggs while a male opens slightly and releases sperm into the water. When spawning for triploid oysters, the hatchery workers will only obtain the eggs from female diploid oysters and discard any diploid sperm to avoid cross contamination. During the spawn, a worker will strip the sperm from male tetraploid oysters and once all female diploids are done spawning, they will introduce the tetraploid sperm to the diploid eggs. After 30 minutes, fertilization rates are calculated and stocking densities are formed.
3-month-old triploid seed – Thomas Derbes II
Why Would a Farmer Want to Grow a Triploid Oyster?
There are many benefits for a farmer to raise triploid oysters. First and foremost, triploid oysters are sterile. This is a major benefit for the farmers during the summer months. During the summer, wild diploid oysters spawn, and when they spawn, the meat turns very thin and watery. In the Panhandle of Florida, the harvest of wild oysters is prohibited in the summer and only farmed oysters can be harvested.
Another added benefit is the increased growth rate of a triploid oyster compared to a diploid oyster. As mentioned above, triploid oysters lack the ability to spawn. Since a triploid oyster does not have to spend energy producing gametes, it puts all of its energy into growing its shell and meat. A typical diploid oyster could take more than two years to reach harvest size, where a triploid oyster can reach harvest size within 8 months (commonly 12-24 months but there are usually some fast growers in a batch).
There are more benefits of triploid oysters including selective breeding for disease resistance and environmental sustainability. With the use of triploid oysters for oyster farming, wild stocks go relatively unaffected and help contribute to more sustainable aquaculture practices. I hope this brief explanation of triploid oysters will help you understand more about the somewhat unknown world of oyster aquaculture. With demand for oysters on the rise, triploid oysters hold great promise in meeting the needs of an ever-growing oyster aquaculture industry.
Health advisories issued by the Department of Health (DOH) due to high levels of fecal bacteria have been a problem for some parts of the Pensacola Bay system for decades. Though most of the samples collected near our beaches rarely require them (usually between 0-5%) the bayous near downtown have been at, or above, 30% of the samples. Bayou Chico is often between 50-60% of the samples. Fecal bacteria have been such a problem in Bayou Chico that it was required to adopt a state Basin Management Action Plan (BMAP) to rectify the problem.
Closed due to bacteria.
Photo: Rick O’Connor
I began following the health advisory reports provided by DOH’s Healthy Beaches Program in 2012. As mentioned above, swimming beaches near our islands rarely have health advisories issued. The problem was with the three bayous near downtown. In 2012 all three consistently reported 30%, or more, of their samples required an advisory to be issued.
To rectify the problem the city and county have been doing a lot of work replacing old infrastructure that allowed sewage to leak from pipes or reach surface waters through sanitary sewage overflows. Many communities around these bayous are converting from old septic systems to sewer, the communities around Bayou Texar are now all on sewer. These same efforts are occurring along the north shore of Bayou Grande, and in neighborhoods around Bayou Chico. Between 2012 and the present, I have seen the frequency of health advisories decline some. Bayou Texar hovers around 30%, some years they are below, others above the mark. In recent years Bayou Grande has consistently been between 25-30%. Bayou Chico has declined some but is usually at or above 30%.
In 2023, for the first time since I began following this, all 13 sites monitored in Escambia County were below 30%.
2023
Body of Water
Number of samples taken
Percent of samples requiring an advisory
Bayou Texar
45
22
Bayou Grande
18
22
Bayou Chico
19
21
Bruce Beach
46
9
Big Lagoon State Park
19
5
Sanders Beach
46
4
Casino Beach
18
0
Park East
18
0
Park West
18
0
Quietwater Beach
18
0
Ft. Pickens
7
0
Johnson’s Beach
7
0
Opal Beach
7
0
It is worth noting that our rainfall was low this year as well. Historically, Pensacola received 60-61 inches of rain a year. Over the last decade this has increased to 70-71 inches. The current rainfall total for 2023 is 58 inches. Many studies show a strong correlation between rainfall and the number of advisories issued. It may very well be that the reduction in rainfall played a large part in the reduction of health advisories. Despite a lot of progress repairing infrastructure, and this effort needs to continue, there are still some issues.
Along with the city and county retrofitting old infrastructure, there are things area residents can do as well.
Many of these are related to poorly maintained septic systems throughout the area. If you are a septic system owner and would like to learn more on how to properly maintain your septic system, contact your county extension office.
If you are a septic system owner and are interested in converting to sewer to reduce the need for maintenance, contact our county extension office. For some communities in the Pensacola area, there is a cost share program with DOH to help make this conversion.
If you are on a sewer system in one of the older parts of town, the pipe leaving your house and connecting to the line under the street is your responsibility and may need repairing or replacing. Many plumbing companies have a television scope that can examine this line and provide you feedback.
For everyone, be careful what your pour down the drain. Fats, Oils, Grease, and even milk can clog the pipes and cause sanitary sewage overflows or backups in the system. Heavy rains only make this worse. In the Pensacola area the Emerald Coast Utilities Authority (ECUA) provides free plastic gallon jugs to place your cooking oil and grease in and, when full, can be swapped for another at several locations around town. To find the closest disposal site to you visit https://ecua.fl.gov/live-green/fats-oils-grease.
The FOG gallon containers are found in these metal cabinets placed around the county.
Photo: Rick O’Connor
Despite low rainfall this year, it is still good that all 13 sites were below 30% this year. With the help of the local governments, agencies, and residents, hopefully it will remain so.
The information provided here can be used by communities all along the Florida panhandle. High fecal bacteria count, and health advisories are not limited to the Pensacola Bay System. Contact your county extension office for more information on how you can help to reduce health advisories in your area.
When you hear about oyster farming, you typically hear the word “seed” and how it is highly important to the future of the farm. While it might not be a typical seed that produces agricultural crops like corn, this seed is a living, breathing (albeit in the water) organism that produces a beautiful, cupped oyster. Depending on market size demand and requirements, it could take anywhere from 8 to 24 months to reach “shucking ready” size. Let’s take a dive into the timeline of an oyster, from seed to shuck.
A cooler full of R6 oyster seed headed out to the farm – Grayson Bay Oyster Company
Oyster farmers typically buy seed from an oyster nursery or hatchery, where they carefully spawn male and female oysters together in individual spawning chambers. Depending on the farmer’s needs, they can produce either diploid or triploid oyster larvae (more on triploids next week). These larvae are free-swimming for the first 2-3 weeks of their life until they develop into pediveligers (Oyster 101). Hatcheries will, for lack of better terms, mix the pediveligers with very tiny grains of ground-up oyster shells. These pediveligers will then attach to a single grain and begin to form into a “seed” oyster. Seed costs range and vary from year to year, and this cost is usually one of the biggest financial purchases oyster farmers can make. Seed is sold by size, starting at 6 millimeters (typically called size R6), and by increments of 1,000. Hatcheries and nurseries are located all along the Gulf Coast, but Florida law requires seed put in the Gulf of Mexico waters and estuaries must come from Gulf of Mexico hatcheries, and the same rules apply to Atlantic waters.
Oyster Seed (>R16) – Thomas Derbes II
Once purchased, these seed oysters make it to their homes in beautiful nutrient-rich waters and grow at a steady rate, and can reach an overall size of 2 inches in 4 to 9 months. During those months, the seed are filtering gallons of water per oyster per day, helping sequester carbon in their shells and consuming large amounts of plankton and algae that could contribute to the eutrophication of the bays. Oyster farmers will check on the seed almost weekly, changing bag mesh sizes and sorting the seed by size. Farmers will also take this opportunity to check for any oyster predators and swiftly evict them from their all-you-can-eat buffet. Sorting is done by using a “tumbler” that has a long drum with holes of varying sizes. This tumbler also helps clean the oyster and chip away at the lip of an oyster shell, causing the oyster to grow deeper and create a beautiful cup.
Farmed oysters do not have a size limit, but most farmers stick to a 2.5 to 3-inch size oyster. These oysters have filtered over 7,000 gallons of estuary water individually and sequestered a very generous amount of carbon, in the form of calcium carbonite (more here), in their shells in their first year of life. Once deemed ready for harvest, farmers will pull them out of the water and get them quickly in the fridge, following strict biosecurity guidelines and regulations to provide a safe product year-round.
Some oysters are fast growers! These were apart of the same spawn. – Thomas Derbes II
And there you have it, from seed to shuck. With the holidays coming up, and seafood sometimes being a part of the holiday plans, reach out to the local oyster farmers in your area to reserve a dozen or two for your favorite uncle. You can also wow the crowd with this very fancy mignonette recipe below!
Lemon Champagne Mignonette
Juice From 2 Local Meyer Lemons (They’re in Season!)
1 Shallot Chopped Finely
½ cup Champagne Vinegar
¼ cup Red Vinegar
1 tbsp each of Green and Pink Peppercorns
24 Local Farm Raised Oysters (For the Environment!)
1. In a bowl, add the juice of Meyer lemons and shallots. Let it marinate for 10 minutes.
2. Add champagne vinegar, red vinegar, and peppercorns to the lemons and shallots.
3. Chill for at least 30 minutes in the fridge.
4. Shuck oysters and top with freshly made mignonette. Enjoy!
I began this project in 2022 wanting to know which of the 40 species of snakes known to inhabit the Pensacola Bay area were encountered by people. I also wanted to know where they were encountering them and what time of year. This information would be used in my Living with Snakes program and provide better information than field guides and publications that covered a broader area. The 40 local species were divided into six categories: small snakes (<12”), mid-sized snakes (12-24”), large snakes (> 24”), water snakes, venomous snakes, and non-native snakes.
The red rat snake, or corn snake.
Photo: Molly O’Connor
Which snakes did people encounter?
In 2023 there were 215 snake encounters between Jan 1 and Dec 10. This is a 136% increase over 2022. This is probably not because of more snakes but rather more residents participating in the project.
Of the 40 species possible, 24 (60%) were encountered. This is a 13% increase over 2022. Again, I feel this is due more to increasing participation.
The most frequently encountered species were:
Cottonmouth – 49 records (23%)
Southern Black Racer – 35 records (16%)
Banded Water Snake – 26 records (12%)
Eastern Garter Snake – 17 records (8%)
Eastern Coachwhip – 11 records (5%)
The Southern Black Racer was the most frequently encountered snake in 2022 (23%), followed by the cottonmouth (16%). As you can see, the frequency of encounters remained the same this year, but the species flipped. The Eastern Ribbon Snake, which was third at (14%) in 2022 did not make the top five this year.
The rarest snakes – those encountered only once or not at all – included:
Encountered once:
Rough Green Snake
Eastern Kingsnake
Eastern Coral Snake
NOT Encountered at all:
Smooth Earth Snake
Marsh Brown Snake
Southern Hognose Snake
Mole Kingsnake
Scarlet Kingsnake
Eastern Indigo Snake
Black Swamp Snake
Glossy Crayfish Snake
Queen Snake
Midland Watersnake
Yellow Bellied Water Snake
Diamondback Water Snake
Western Green Water Snake
Western/Eastern Mud Snake
Rainbow Snake
Of the four species only encountered once, each is considered quite rare for encounters. The Eastern Kingsnake was once common but has declined over the years. The Eastern Coral Snake is quite common, but its behavior and activity make it rare to encounter. Some snake experts have never seen one in the wild.
Of the 16 species not encountered at all, three are small snakes whose size and habits make them difficult to detect. Two are mid-sized but their habits also make them hard to detect. Nine are water snakes who live in swampy environments along our rivers. You would have to be out there to encounter them, and few people are. Two species, the Southern Hognose and the Eastern Indigo Snake, are state and federal listed and are extremely rare.
The gray rat snake, also known as the oak snake.
Photo: Nick Baldwin
Where did people encounter these snakes?
I divided the bay area into four regions: North Escambia, South Escambia, North Santa Rosa, and South Santa Rosa.
North Escambia – 13 species (54% of the total 24 species found this year).
South Escambia – 16 species (67% of the total).
North Santa Rosa – 17 species (71% of the total).
South Santa Rosa – 11 species (46% of the total).
There is not much difference between these. In Escambia County more encounters occurred in the southern portion of the county. For Santa Rosa County it was the opposite. Whether this is because there are more snakes in these locations, or more participants in the project cannot be said. We will pay more attention to this next year.
Species that were found in ALL four regions included:
Eastern Garter Snake
Gray Rat Snake
Corn Snake
Southern Black Racer
Coachwhip
Cottonmouth
Species only found on one of the four regions included:
Eastern Kingsnake
Florida Pine Snake
Brahminy Blind Snake
Rough Earth Snake
Pinewoods Snake
Eastern Coral Snake
What time of year were these snakes encountered?
Winter – 57 encounters; 13 species
Spring – 80 encounters; 20 species
Summer – 52 encounters; 18 species
Fall – 17 encounters; 10 species
There was an obvious decline in encounters in the fall. Many species are beginning to settle in for the winter this time of year, but many others breed, and thus should be moving (at least the males). I know some volunteers ceased looking, but others I know who search weekly, or daily, did not encounter as many snakes.
Only one species was encountered every month of the year. This was the cottonmouth.
The Eastern Garter Snake was seen every month except June and October; it seems to be active year-round.
The Southern Black Racer was missing in January, November, and December – suggesting a dislike for the cold.
NOTE: many of these hibernating snakes will emerge on warmer sunny days during winter and can be encountered.
SPRING was the time of year with the highest encounter rate and species encountered. This would make sense in two parts; (1) they are emerging seeking food after non-feeding during winter, (2) they are emerging looking for mates because it is breeding season for many. Five species were only encountered in the early part of the year. Two species were only found in winter and one species was only found in the spring.
Eastern diamondback rattlesnake crawling near Ft. Pickens Campground.
Photo: Shelley Johnson
What about the venomous snakes?
As expected, most are concerned more about the encounters with venomous snakes. There are six venomous species listed in the state of Florida, four inhabit the Pensacola Bay area. All four were encountered in 2023.
Cottonmouth – was encountered in all regions, each month of the year, it was the most commonly encountered snake in our area this year.
Eastern Diamondback Rattlesnake – was encountered seven times, only during the spring and summer, and in three of the four regions in our area. This snake is pretty common but not commonly encountered where people most often reside and play. Though encounters do occur in residential neighborhoods, they are rare.
Dusky Pygmy Rattlesnake – was encountered six times, during spring, summer, and fall, and two of the four regions in the bay area.
Eastern Coral Snake – was encountered once, during the spring, and in only one of the four regions in the bay area. Again, this snake is actually quite common, but its behavior makes it difficult to encounter. So, encounters with this species are rare.
Summary
In 2023 60% of the known species of snakes that inhabit the Pensacola Bay area were encountered by residents at some time during the year. Most encounters occurred in the spring and summer and encounters occurred throughout the entire region. The cottonmouth was the most frequently encountered species this year but rare species, such as the Eastern hognose, Eastern kingsnake, and the Florida pine snake were seen – and that is pretty exciting. The snake diversity in the Pensacola Bay area seems good. There is concern that a non-native parasite decreasing the populations of some species in central and south Florida may make its way to the panhandle. We are participating in a project entitled Snake Lungworm Alliance Monitoring (SLAM) that collects deceased snakes for examination by researchers. If you find a deceased snake in good enough condition to be dissected, place it in a plastic Ziplock bag, label with the date, location (GPS preferred), and your contact information. You can then bring it to the Escambia County Extension office or freeze it and call me – (850-475-5230) or email roc1@ufl.edu and we will arrange pick up.
We plan to continue the Snake Watch Project in 2024 and encourage all who see snakes to contact me at the above email address. We will also be offering the Living with Snakes presentation. If your community group is interested in this talk, contact me.
I am going to end 2023 with an article on a project I hope to conduct in 2024. It will focus on insular cottonmouths and will focus on the western panhandle, though those in the eastern panhandle might be interested and could help. For obvious reasons, conducting this project as a citizen science one is not the best idea. Cottonmouths are venomous snakes and can be dangerous, but there could be opportunities where citizens could be of help (a road killed snake for example).
The cottonmouth is one of the more commonly encountered snakes in the western panhandle.
Photo: Bob Jackson
The story is quite interesting. Most books and articles on cottonmouths indicate they inhabit freshwater habitats where water flow is slower. Though found in the back waters of rivers, they are not as common within the rivers themselves. Golf courses, ponds, lakes, and reservoirs are other places they frequent. There are records of them on coastal barrier islands and in the upper Florida Keys. Swimming across saltwater is not surprising but existing on a xeric, sandy barrier island would not fit the typical habitat of this snake. Most of the accounts on barrier islands are in the Big Bend region and many know that there are freshwater habitats on some of these islands. If a cottonmouth could reach the island, there could be a suitable habitat for them. But you could argue that these habitats are not large enough to support a large population. The carry capacity of a population is determined by the amount of space and resources available. Cottonmouths are opportunistic feeders – so, finding food would not be a big issue – but with limited acreage of needed freshwater the carrying capacity would be lower, and populations of cottonmouths lower as well. Then there is Seahorse Key.
Seahorse Key
Photo: Courtesy of flicker
Seahorse Key is 3 miles southwest of Cedar Key and can only be accessed by boat. It is said that the density of cottonmouths is higher there than anywhere in the state. Dr. Coleman Sheehy (University of Florida) stated they typically encountered 30 snakes while conducting beach walk surveys and they estimated about 600 cottonmouths on the island. The fact that cottonmouths were there was not surprising, but the high density – in a habitat not really suitable for such – was.
Depending on which source you use, there are up to three subspecies of cottonmouths found in the U.S. The Florida cottonmouth (Agkistrodon piscivorous conanti) is the one found on Seahorse Key, the rest of peninsula Florida, and in the panhandle as far west as Gulf County. The eastern cottonmouth (A.p. piscivorous) is found from Bay County west to Escambia County on the Florida/Alabama line, and north into the coastal plains of Alabama and Georgia. The western cottonmouth (A.p. leucostoma) is found from the Alabama/Florida line west to Texas and north to Arkansas. Dr. Harvey Lillywhite (University of Florida), and others, were curious as to whether the Florida cottonmouth was adapting to saltwater. An interesting question and, again, how these snakes are surviving and thriving on Seahorse Key is a part of understanding this story. In recent years there has been a push to declare the Florida cottonmouth its own species – Agkistrodon conanti. The Florida Museum of Natural History’s history article1 on cottonmouths list as such. Dr. Steve Johnson’s article2 lists the snake as Agkistrodon piscivorous and leaves it there, not dividing into subspecies. Many current researchers agree with the identification of A. conanti for the Florida cottonmouth – the one found on the islands of the Big Bend – and the one of interest in whether it is adapting to saltwater environments. That brings me back to the project we are planning to begin in 2024 in the western panhandle.
Cottonmouths definitely exist on the barrier islands in Escambia County. We have two islands – Santa Rosa Island and Perdido Key. There are freshwater sources on both islands and suitable habitat for cottonmouths. The swim from the mainland to reach these islands is much shorter than for those at Seahorse Key. At Perdido Key a swim of 600 feet would allow a snake to reach the island – easy. The swim from Perdido Key to Santa Rosa Island is less than a mile (about 4000 feet) but the currents in Pensacola Pass are strong and the likelihood of a cottonmouth accessing Santa Rosa Island this way would be low. However, there are many locations along Santa Rosa Island where the swim would be no more than a mile from the mainland and some, in Okaloosa County, the trip could be made in about 800 feet. Island access is easy.
As the Escambia County Extension Agent, I handle the snake calls that come to our office – and there are a lot of them. In recent years there has been concern from some Perdido Key residents with the number of cottonmouths they are encountering. One of their questions was whether this was an unusually high encounter rate – Seahorse Key all over. Conducting surveys in their neighborhood in 2019 I encountered cottonmouths 70% of the time – all of them were juveniles or subadults. I recommended some landscape changes to deter the snakes from their yards and in 2020 the encounter rate dropped to about 40% of the surveys. However, it did not rain as much in 2020 and this could have affected the snakes as much, if not more, than the landscaping changes. The freshwater ponds in the neighborhood used by the snakes were small and ephemeral – they did not have water unless rainfall was present. So, we did another survey in 2021, it rained more, and encounters increased to 50% of the surveys. The landscaping may have helped some. In 2021 I also conducted surveys in the nearby state park and found no significant difference in snake encounters (50%) but the time of day for encounters was different and I did find adult snakes in the state park.
Note here… I get very few calls on cottonmouths from Santa Rosa Island. Rather their calls are about eastern diamondback rattlesnakes, which are not encountered as much on Perdido Key. The question we have on the table now is whether the cottonmouths found on Perdido Key are the Florida cottonmouth (A. conanti) – the one some believe may be adapting to saltwater conditions. According to Whit Gibbons and Mike Dorcas’s Snakes of the Southeast3 Escambia County Florida is the border between the eastern and the western cottonmouth. This same guide suggests that the Florida cottonmouth does not exist here.
So here is the project… which species/subspecies of cottonmouths exist on our barrier islands in the western Florida panhandle?
How do you tell them apart?
The difference between the Florida cottonmouth and the eastern/western are very minor. This makes identification in the field hard and dangerous. The Florida cottonmouth will have two distinct stripes running vertically across the front of its snout. The eastern/western cottonmouth will not have these. To determine whether these stripes exist requires getting much closer to the snake than is recommended. THIS IS A DANGEROUS SNAKE AND CLOSE ENCOUNTERS ARE NOT RECOMMENDED. However, a road killed snake can be examined using a stick at least 12” long. NOTE: SNAKES, EVEN RECENTLY KILLED, HAVE BEEN KNOWN TO BITE. DO NOT HANDLE A DEAD SNAKE UNLESS YOU ARE SURE IT IS DEAD. You may have a camera that can get a good photo of the snout FROM A SAFE DISTANCE (cottonmouths like to rest with their head tilted upwards at a good angle for such a photo).
You can see the light vertical bands on the snout of this snake indicating it is the Florida cottonmouth.
Photo: University of Florida. Notice the light bands across the snout of this Florida Cottonmouth.
Photo: Kristen Grace. This cottonmouth has a uniform coloration across the snout – indicating that it is an eastern cottonmouth.
Photo: Ricky Stackhouse.
We are planning a program on this project in early April for Escambia and Santa Rosa Counties. If you are in Okaloosa, Walton, or Bay counties and would like the program presented there – let me know.
