From Seed to Shuck – More Oyster 101

From Seed to Shuck – More Oyster 101

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.

Cooler Full of Seed Headed To Farm
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
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.

Oysters of varying size
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!

Between The Hinge, What is an Oyster?

Between The Hinge, What is an Oyster?

They’re consumed worldwide, from 5-star exclusive restaurants overseas to your flip-flop beach bars right here in the Florida Panhandle. They have many different preparation techniques, such as plain and simple with a squeeze of lemon and a dash of hot sauce to “dip-your-bread-innit” chargrilled parmesan Cajun garlic butter (recipe below). However, many of their consumers actually don’t know what an oyster is, and as luck would have it, here’s a quick oyster 101!

Anatomy

Many people ask me what exactly an oyster is? Before becoming an oyster farmer, I always referred to them as “rocks with tasty meat in them,” but I couldn’t be further from the truth. Oysters are actually complex individuals that go through many metamorphoses and transitions throughout the first 2-4 weeks of their life, this includes a period of free-swimming followed by walking around with its “foot.” Let us look under an oyster’s top shell and identify some key organs.

Anatomy of an oyster
The anatomy of Crassostrea virginica (Eastern oyster) – Thomas Derbes

Mantle – A very thin, dark, fleshy layer of tissue that surrounds the oyster’s body. This is where shell formation begins!

Hinge – The shucker’s worst nightmare. This, along with the adductor muscle, is responsible for the opening and closing of the shell.

Adductor Muscle – Helps keep the oyster shut and protected from any predators. This part must be severed in order to fully open the oyster.

Gills – Thin, delicate structures found inside the body of the oyster. They serve a crucial role in respiration and feeding. Gills are shaped like tiny, finger-like projections that provide a large surface area for oxygen extraction, and they also trap and transport food towards the mouth.

Heart – Oysters have a simple circulatory system with a three-chambered heart that pumps colorless hemolymph throughout their body to distribute nutrients and oxygen.

Biology

Crassostrea virginica (or as we know them, the Eastern oyster) is a native species of oyster that is commonly found along the eastern coast of the USA, from the upper New England states all the way to the southernmost tip of Texas. Eastern oysters prefer an estuarine environment (mid-salinity) but can be found in some coastal areas with higher salinities, especially in south Florida. As filter feeders, they trap nutrients like plankton and algae from the environment and require a habitat that can handle their filtering power (30 gallons per day).

The first 2 – 3 weeks of an oyster’s life is completely different than most people expect from an oyster. Females and males coordinate their spawning time with different cues and release massive amounts of eggs and sperm into the water. This type of spawning behavior is considered batch spawning, and a majority of the fertilized eggs perish before adulthood due to predation and other environmental causes. Once fertilized, the fertilized eggs go through multiple divisions and approximately 12-24 hours later, the free-swimming trochophore larvae are formed. These larvae swim around in the water column for 2-3 weeks, developing their shell and forming into a veliger, which closely resembles their adult stage. Once ready to settle, the pediveliger is formed. The pediveliger has a “foot” and walks around the bottom, looking for a suitable place to settle (usually another oyster). Once a suitable location has been found, the foot will secrete a substance to cement them into place and the pediveliger will metamorphose into a juvenile oyster, also known as spat. Oysters can grow very rapidly after their settlement, with oysters reaching 3 inches (usual harvest size) within 18 months.

Oysters have been known to establish massive reefs in estuaries, but their numbers have been on a rapid decline across the southern USA since the 1960s. These oyster reefs provided a massive natural, biological filter in the bays, and also were home to many juvenile and adult fish and crustaceans. Currently, there are many agencies and foundations that have oyster restoration at the top of their agenda, and the future is looking brighter for the oyster populations.

Oyster Life Cycle
The Oyster Life Cycle – Maryland Sea Grant

Pearls of Wisdom

I hope this quick oyster 101 helped shed light on the otherwise unknown life of the Eastern oyster. With the holidays coming up, make sure you grab some oysters to shuck and share with family and friends, and look at their shocked faces when you bust out all this wonderful oyster knowledge. Who knew that an oyster was much, much more than a “rock with some meat in it.”

Chargrilled oysters kissed with flame
Chargrilled “DYBI” Oysters Kissed With Flame – Thomas Derbes

“Dip-Your-Bread-Innit” Chargrilled Oysters

24 Oysters

2 Sticks of Butter

2 Tablespoons (or more) of Cajun Seasoning (Uncle Tony, Zatarains, etc)

½ cup of Hot Sauce

½ cup of Lemon Juice

1 Tablespoon of Granulated Garlic

2 cups of Mozzarella Cheese

½ cup of Parmesan

1 Cup Panko (The Razzle-Dazzle)

Sliced Bread (Baguette, Wonder, any bread honestly)

———————————————————————————————————

  • Shuck Oysters – Many instructional videos online, and make sure you use an actual oyster knife, clam knives are no good!
  • Add butter to pan/pot. Melt the butter on medium, then add everything but the oysters and cheese to the butter.
  • Start your grill, charcoal/wood is best for adding a smoky flavor. Once the butter mixture is made, add oysters to the grill and spoon your butter mixture into the oysters.
  • Mix the cheeses together and add the cheese mixture to the oysters once the butter is spooned on. For a little razzle-dazzle, mix 1 cup of panko into the cheese mixture.
  • Cook oysters until bubbling. Make sure to not overcook the oysters, and once you seed the mixture bubbling, they are good to remove.
  • Eat the oysters and dip your bread in the shell to soak up the juices. You won’t regret it.
It’s Been a Cruel Summer, Especially for Southern Oyster Farmers

It’s Been a Cruel Summer, Especially for Southern Oyster Farmers

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.        

Bacteria at the Beach

Bacteria at the Beach

Recent news reports have Panhandle Beaches trending on social media. Beaches are open and ready for holiday weekend. Here's information to help make sure you are ready too.

Recent news reports have Panhandle Beaches trending on social media. Beaches are open and ready for the holiday weekend. Here’s information to help make sure you are ready too. Photo by Florida Sea Grant.

The threat of bacteria in coastal waters can be scary and a challenge to understand. Here is information that helps clarify the threat to beach visitors and recreational users of marine waters. This is a good opportunity to think about bacteria exposure risks related to the coastal environment that we can control. It is important to remember the probability of severe illness in a normal healthy individual is very low.

There are two different un-related groups of bacteria species that often are cited in the news.  One general group is fecal coliform and the other group are marine specific known as Vibrio.

Fecal coliform including Enterococci bacteria are used by public health managers as indicators of water quality. High levels of these bacteria can indicate an elevated health risk for beach visitors. For some individuals contact in impacted waters can result in gastrointestinal issues like nausea, vomiting, stomachache, diarrhea, headache or fever. Other symptoms might include rashes, sore throat, ear ache, and other cold-like or upper respiratory symptoms.

When “no-swimming” advisories are posted you can avoid these concerns by following warning and guidance information. Many times advisories are for specific locations due to storm run-off and water circulation patterns. If an area has a warning or is closed, usually there are better choices for swimming activities nearby. The Florida Department of Health has an established testing of many of Florida’s coastal swimming areas. The latest guidance information can be found at http://www.floridahealth.gov/environmental-health/beach-water-quality

On the other hand, Vibrio exposure that results in illness is potentially more severe. The US Centers for Disease Control and Prevention now estimate 80,000 Vibrio illnesses and 100 deaths occur annually in the United States. In perspective, The Clean Beaches Coalition estimates 180 million Americans annually make 2 billion visits to ocean, gulf and inland beaches.

According Georgia Sea Grant’s SafeOysters.org website and research, many Vibrio infections are not reported and usually do not cause serious or life-threatening illness in healthy people, although they may cause gastroenteritis (nausea, abdominal pain, vomiting, and/or diarrhea) or cellulitis (skin infection). For a Vibrio infection to occur there must be an entry point into the body. This usually is either through water entering an open wound or eating raw or undercooked seafood.

Symptoms of infection due to consumption of raw or undercooked seafood often develop in 12 to 48 hours and may include:

  • Fever/chills

  • Nausea/stomach pain/vomiting

  • Diarrhea

Individuals with weakened immune systems, chronic diseases or conditions, or undergoing certain medical treatments (see list below) are more susceptible to Vibrio vulnificus infections and are also more likely to become seriously ill or die from them. The fatality rate may be as high as 61% for Vibrio vulnificus infections in people that have been diagnosed with one or more of the following health conditions:

  • Liver disease (from cirrhosis, hepatitis, or cancer)

    No need to feel left out! Fully cooked oyster dishes like Oysters Rockefeller are a coastal classic that's safe and tastes great!

    No need to feel left out! Fully cooked oyster dishes like Oysters Rockefeller are a coastal classic that’s safe and tastes great! Photo by Florida Department of Agriculture and Consumer Services.

  • Diabetes

  • Alcoholism

  • Kidney disease or failure

  • Cancer (includes lymphoma, leukemia, and Hodgkin’s disease)

  • HIV/AIDS

  • Stomach disorders including surgery, taking acid reflux medication or antacids

  • Hemochromatosis (iron overload disease)

* If you are unsure of your risk, consult your doctor. You can always indulge in great oyster recipes that are fully cooked like Oyster Rockefeller or oyster chowder.

Perhaps one of the most common group of listed individuals are those taking acid reflux or heartburn medications. This would also include antacids and prescription medications for acid reflux and other common digestive conditions. Many of these medications work by reducing acid which can potentially increase pH in the digestive system. This lowers the natural defense barrier to several foodborne bacteria including Vibrio. If you take these medications do not eat raw or under cooked seafood. If you have any question about your risk, consult your doctor.

An oysterman uses his 11 foot long tongs to collect oysters from the bottom of Apalachicola Bay Photo: Sea Grant

An oysterman uses his 11 foot long tongs to collect oysters from the bottom of Apalachicola Bay
Photo: Sea Grant

Shellfish harvesting is managed by the Florida Department of Agriculture and Consumer Services – Division of Aquaculture and Florida Fish and Wildlife Commission. This is done in cooperation with Florida’s certified shellfish harvesters and processors. While Vibrio counts may be higher in warmer weather, shellfish harvest areas are monitored all year. A system of specific harvest protocols are consistently maintained. Florida’s regulatory agencies and seafood industries work together with the goal of having the safest shellfish supply at all times of the year.

As mentioned earlier, Vibrio can also enter the body through open wounds. Vibrio is sometimes misnamed as “flesh-eating” bacteria.  “Flesh-eating” is not a medical term and was likely derived from the fact that tissue death, or necrosis, can occur during advanced, late stages of infection around a wound if it is left untreated, especially in those with weakened immune systems (Oliver 2005). The best advice is to seek medical attention early if you experience any of these symptoms or have suffered cut or puncture injury in coastal waters. (See Vibrio FAQs from UF/IFAS and Florida Sea Grant)

The rod-shaped bacterium known as Vibrio. Courtesy: Florida International University

The rod-shaped bacterium known as Vibrio. Courtesy: Florida International University

Wound infection symptoms may develop within 3 to 24 hours and include:

  • Rapid swelling, pain, and reddening of skin around wound (present in 100% of infections)

  • Large blisters, die-off of tissue around wound (30 – 50% of infections)

  • Gangrene (<10%)

If Vibrio vulnificus infections are left untreated in people at risk for serious infection, symptoms may quickly increase in severity and include:

 

  • Fluid accumulation, especially in legs

  • Blood-filled large blisters, mainly on extremities

  • Septicemia (bacteria enter and spread through blood stream)

  • Shock (rapid drop in blood pressure)

  • Death

For additional information and details please visit SafeOysters.org

Here are some final thoughts and advice:

  • Remember the majority of healthy individuals will not have any problems.

  • If you are recovering from illness know your limits and use the above resources to make informed decisions to protect your health.

  • Plan your beach vacation for safety but then confidently relax and enjoy the experience.

  • For additional beach safety and enjoyment of our natural resources see our other articles on the UF/IFAS Panhandle Outdoors website.

A great blue heron at sunset stalks the shoreline ready for his next meal. Scenes like this await coastal visitors. It's an experience like no where else. Photo by the author.

A great blue heron at sunset stalks the shoreline ready for his next meal. Scenes like this await coastal visitors. It’s an experience like nowhere else. Photo by the author.

An Equal Opportunity Institution. UF/IFAS Extension, University of Florida, Institute of Food and Agricultural Sciences, Nick T. Place, dean for UF/IFAS Extension. Single copies of UF/IFAS Extension publications (excluding 4-H and youth publications) are available free to Florida residents from county UF/IFAS Extension offices.

Harvesting Safer Oysters – “From Bay to Table”

Harvesting Safer Oysters – “From Bay to Table”

Oysters on the half shell

Oysters on the half shell ready to eat! Photo Courtesy of Florida Sea Grant

Making oysters a healthy and sustainable seafood choice is the goal of oystermen and seafood dealers across the nation and the state of Florida. New education programs for the oyster industry went into effect January 1, 2014 and were implemented by the Florida Department of Agriculture and Consumer Services (FDACS) this past spring. FDACS oversees oyster resources and seafood dealer certification.More information about FDACS division Aquaculture can be found at http://www.freshfromflorida.com/Divisions-Offices/Aquaculture .

As our fall harvest areas reopen, many local oystermen are now viewing a new 25 minute video which is now required along with a Commercial Saltwater Products License to harvest oysters commercially. Florida Fish and Wildlife Commission (FWC) issues licenses for both commercial and recreational oyster harvesters and enforces laws related to harvesting. More information regarding proper licensing can be found online at http://myfwc.com/license .

All harvesters can do their part to insure seafood safety by following important harvesting guidelines. These include time and temperature protocols in the collections and transportation of shellfish to the dealer or home. Also important, are harvest boat safety, condition, and sanitation practices. Protection of oyster resources through proper culling and following the 3” inch size limit is important to creating sustainable oyster resources. The new video provides this education and an Oyster Harvester Training Certificate for commercial harvesters is available to those who watch the video at the following FDACS and UF/IFAS Extension Offices by appointment:

FDACS Field Offices:

Melbourne Office: 321-984-4890

Port Charlotte Office: 941-613-0954

Cedar Key Office: 352-543-1084

Tallahassee Office: 850-617-7600

Apalachicola Shellfish Center: 850-653-8317

UF/IFAS Locations:

Bay County: 850-784-6105

Franklin County: 850-653-9337

Santa Rosa County: 850-623-3868

This harvesting and training information is also appropriate for recreational harvesters even though it is not required.

Recreational harvesters regulations and instructions can be found at http://myfwc.com/fishing/saltwater/recreational/shellfish .

Seafood safety is of interest to everyone,including harvesters, seafood dealers, and consumers. Each year there are a relatively small number of serious cases of foodborne illness as result of shellfish consumption. Often illness is a result of poor choices made by consumers. Consumption of raw oysters or other shellfish is not recommended for individuals with compromised immune systems. Poor immune systems are often the result of liver-disease or when chemotherapy treatment is used. Patient diagnosed with diabetes, iron overload disease, and HIV/AIDS are also advised not to consume raw shellfish.

New research also suggests another risk group are patients with acid reflux and digestive issues. Some over the counter and prescription medications, including antacids and proton pump inhibitors, increase stomach pH which allows more potentially harmful bacteria to survive ingestion, leaving patients at a higher risk for a variety of foodborne illnesses. The best advice is to consult your doctor if you have questions about whether consuming raw shellfish is appropriate for your health concern. Cooking is also a tasty way to safely prepare and enjoy shellfish. For additional guidance please visit http://safeoysters.org .