Jeri's Seafood ~ Generations on the Water, Part 2

Most oysters do not have a fixed sex that stays with them throughout the course of their life, they can change from male to female over the course of a lifetime and many contain both egg and sperm. After reaching maturity, which takes about a year, they release sperm into the water, but it takes the older more mature oysters to release the eggs. The sperm and eggs meet in the water to fertilize and develop into larvae, a process that takes about six hours. 

“Oysters spawn typically in May and June when the water starts warming up to about 75°,” explained Justin. “Normally you need some fresh water for them to start spawning, so you have salinity change and temperature change. We use what we call cultch, which is basically just rock or shell, anything an oyster will stick to. You put the cultch in the water, the oysters will spawn and eventually the larvae will set. When they first land that’s the only time an oyster has legs, they can actually crawl around and find something to set on, and once they set they are known as spat. When an oyster dies it automatically opens and many times the larvae set on the open shell. You might have a hundred baby oysters that have attached themselves to one oyster shell, but then the crabs come through and drum and fish and they pick off the ones they want, you might have two that survive out of the one or two hundred that set there. But you wouldn’t want all of them to survive because it would be way too overcrowded. If they don’t find something to set on, they won’t survive but once they set, they’re there, and they start growing. You just have to have some material there and the right conditions. As long as the conditions are right in the area and you have enough seed oysters that are spawning, you can bring an area back pretty quickly and that’s what they did in the Chesapeake Bay area. Maryland and Virginia are predominately private leases, they’re not public waters. In public waters you have the tragedy of the commons, which is when anything that is public and you release people out there freely they have no duty to protect it, they want to get as much as they can as quickly as they can before anyone else does. So, public reefs, just like anything else public, are just not that efficient. If you invest your own money and grow your own oysters, now you’re going to take care of them and preserve them. Virginia and Maryland are a testament to how well that works. Because of their management, Texas went from being number one in the nation to being third or fourth.

“Oysters grow their own shell, which is basically calcium carbonate,” noted Justin. The oysters eat phytoplankton. Phytoplankton absorbs carbon dioxide from the atmosphere and uses it for photosynthesis; which is the main food source for oysters. When oysters filter water through their gills the phytoplankton are trapped in the gills and moved to the oyster’s mouth for digestion. “Oysters use the carbon dioxide and calcium carbonate to build their shells. Because of the oysters eating the phytoplankton which has pulled the CO² out of the atmosphere, there’s actually carbon sequestration in oysters, so the oyster shells become a geological storage for CO². Recently, Exxon and Chevron and others were taking carbon and storing it underground. They’ve leased a bunch of land in Chambers County for that purpose, but they have to monitor it forever. Oysters consume the CO², they build their shell, the shell becomes part of the reef, and as long as it’s not messed with, that’s a geological storage for carbon,” he affirmed.

Oyster boats are called luggers, the name is derived from the word lug which means to carry or drag a heavy load. So, a lugger is something that lugs. Richard Bricker, in his book Pearls on Galveston Bay, wrote. He added, “Generally, the lugger will be relatively shallow draft with a flat bottom. A scow or barge type bow is also sometimes used. This was the usual design for sailing sloops and schooners since the mid-1800s all along the Texas Gulf Coast for at least two reasons. One was that our shallow waters dictated a flat bottom to minimize the draft and distribute the load when running aground thus preventing hull damage. Another significant reason is that such a design is much easier to build especially with wood. The scow type bow eliminates the compound curves of a sharp bow and cuts out the need for steaming the wood and the subsequent complexities. Many of the early scow sloops were built right on the beach and Joe Nelson’s steel lugger Security was built in his sister’s yard. Just a good welder, some laborers, and Joe supervising were all that was needed. Another significant difference of the true oyster lugger is a second wheel and controls forward so that the captain is facing aft such that he can see and control the dredge coming in as he dredges in a circle. The larger luggers also have bunks, a galley, and a head, which permits oystering in other areas of the Gulf Coast when needed.”

“Luggers were purposely built for oystering,” said Justin, “they’re large enough to haul shell back out into the bay. Initially they were built large to use for transplanting oysters, now we use them to put shell back out on the reefs and hold our coolers for refrigerating the oysters at harvest. 

“We have our own oyster boats which usually go out about five a.m. and return to the dock around noon to three, depending on how many sacks they get,” declared Justin. “We only produce about a third of what we process. We bring in the remainder from Louisiana, Mississippi, Maryland, Virginia and everywhere and process them. In our operation here we start by planting cultch, once you plant that, you’re going to get off it and you’re not going to touch it again because once they start growing you don’t want to be out there with a dredge working on top of all the new oysters. They’re really fragile at that stage; you want to wait until they get at least two inches before you go out there and start dragging them around. That takes about ten to fifteen months depending on the amount of rain and the salinity of the water. We have some leases that are right off the tip of Smith Point where the Trinity River feeds in. The oysters there are the first to die when the water gets real fresh, but they also grow the quickest because of all the nutrients that come down. You can grow a three inch oyster there in about sixteen months. If you get out across the bay it’s going to take you a full two years. Once you start dragging them around you break up the clusters so you can get single oysters. You keep cultivating them like that until they reach three inches and then we harvest them. That’s state law; they have to be three inches to harvest. If our customers order today, we’re going to deliver tomorrow, so once we get an order we go out that day to harvest. Not too many people do that and logistically, sometimes it’s very difficult because of weather and other circumstances. So we get our orders, the boats come in and we start processing that day and they get put on the truck and delivered the next day. 

In all the bays you have restricted areas where they don’t allow oyster harvesting due to the potential for pollution. In Galveston Bay that would be the area coming out of Channelview because of all the refineries and areas where there are large drainage ditches coming into the bay. So, you have an open area and a closed area and it’s a finite line. You might have a public reef on both sides that crosses the line. So to discourage people from going over into the restricted water during open season and potentially getting somebody sick, they allowed lease holders to start transplanting the oysters. You could transplant them from the restricted area, put them over on your private oyster lease and let them depurate (filter) for two weeks. The last transplant took place in 2014, as there’s really no longer a need for it. 

“My grandpa and dad started putting our oyster shells back on our leases a long time ago and then we started buying river rock to put on top of our established reefs. Everybody else was selling their shell to companies who ground them up to make chicken feed instead of putting it back on their leases.  The shell is loaded from our dock onto a barge. Each barge carries about 330 cubic yards of shell which is around 300 tons. We use water pressure to blow the oysters off the barge and onto the reef,” explained Justin. They use a large pump, mounted on the barge that puts put 1500 gpm at 200 psi through five turret-mounted nozzles along the barge’s length. “The timing of putting the shell out is important as well, as it is best to coincide with the onset of the larvae’s maturity,” explained Justin.  “Oyster shell will eventually start decomposing, especially in higher salinity, so it turns into a shell hash. Shell hash gets moved around in the tide; a spat might stick to that but its survival rate is not good, as it will end up getting covered up and killed. If river rock is on top and spat attaches to it, it will not get moved away from the reef and it also makes a prettier rounder shell. Shell is best for the base of the reef and the river rock on top to catch the spat.”

“We shuck oysters and we sell oysters to half shell markets. In the cages, to get a pretty half shell oyster like you see in the restaurants you have to go out and tumble the oysters and flip the cages over to let them air dry and kill the algae. There’s a lot of work that goes into it. While we’re harvesting our oysters on the bottom with a dredge or a rake, it’s naturally tumbling all the other oysters that you’re not catching, so you’re knocking the growing edge off to make them grow a deeper cup. Oysters have a growing edge and they normally grow long and skinny, but if you knock that growing edge off the oyster will put that energy into just growing deeper. 

Oyster farming has a surprising number of benefits that go well beyond producing a tasty seafood. Besides the benefit of oysters for natural carbon sequestration that has already been noted, they are a great ecological benefit. Being filter feeders they filter the water for clarity. A single oyster can filter up to 50 gallons of water per day.  They provide habitat and breeding ground for almost every fish. They secrete pseudo feces, particles of grit that cannot be used as food wrapped in mucous, which the smaller fish eat on and that brings in the bigger fish. Oysters are good for preventing erosion. If you have a reef built close to the shoreline it protects it from erosion. Large oyster reefs can serve as buffers, helping protect coastal communities from storm surges and flooding. Lastly, oysters recycle nutrients, helping balance ecosystems and preventing harmful algal blooms.