In Part 1, we explored the oyster flavor profile – the taste, texture, and finish of the oyster, and how to taste it. We talked about how many factors can affect the oyster’s merroir. These factors include:
- local water qualities
- farming methods used
- where the oyster grows within the farm
Today, let’s dive into…
The Life Cycle
For the oyster, life is relatively simple. For the farmers, it’s quite a bit more complex and intensive. Every step of raising an oyster, from spawning to service, is labor intensive. At the beginning of 2017, we can automate so many processes just as easily as having a person complete them. When it comes to oyster culture, there is a person involved in every step of the process. Often, there are several. Farmers handle each oyster several times before harvest. Doesn’t that make it as much an art as a science?
Several ways to spawn
Shellfish can spawn as young as six months of age. Hatcheries usually like to wait until their broodstock oysters are two years of age.
If you’re thinking of spawning oysters yourself, do some research first. There are upward of a dozen different methods used to complete the process. Some biologists keep each oyster to a small tank and then mix the water after the spawning is complete. Others will put hundreds of oysters together for the spawning.
The process starts the moment the biologists place the oysters in their tanks. Within a short while, the oysters begin to filter the water. When this happens, the biologists will shock them with temperature. The word doesn’t mean quite the same thing it would if someone was shocking you. Over several minutes, the biologists increase the water temperature by about ten degrees Celsius. This incites oyster spawning behavior. Now is the first time you would be able to differentiate a female from a male visually. Females spurt eggs out of the bills (front) of their shells as they snap shut. Males leave their shells open and continuously release sperm. Next step: fertilization.
A free-floating larvaehood
Let’s say for a moment you had a powerful microscope and the patience to watch oysters grow into spat. The first sign of life would be when the egg’s nucleus disappeared after five minutes. After a day, it would have doubled in size. At nine days, there would be a shell. After two weeks of being light enough to swim and float, the oyster would weigh enough to fall to the ocean floor. From that time, a wild bivalve doesn’t move around much. It naturally grows and filters the water around it.
For the cultivated oyster, however, this is just the beginning.
Over the next couple months, the biologists will transfer the oysters from tank to tank. They give their oysters everything necessary to be healthy and grow. Once each oyster is about the size of a thumbnail, they’re ready to move on to the farm. The spawners sell the oysters to the farmers as oyster seed.
Several ways to raise an oyster
Some farmers keep their oysters in the protective tumble bags their entire lives. That’s exactly what it sounds like – the farmers anchor the bags so they can thrash about with the flow of water. Others will throw spread them to live on the floor of the farm, a selection known as bottom culture.
Some farmers plant their oysters on the sand in shallow water. Often this means these oysters will Others place their oysters in deeper water. Some plant their oysters on sandy substrate. Others don’t plant them at all, but put them in tumble bags to live out their lives. All these preferences affect how oysters look and taste when you enjoy them.
When the time to harvest the oysters comes, there are several methods the farmers use. If the oysters are in the tumble bags, it’s a matter of pulling them up out of the water. This might sound easy until you see that they’re harvesting hundreds of bags. Each bag contains thousands of oysters.
There are several techniques farmers can use to harvest bottom culture oysters:
- by hand/tongs
- hydraulic dredge
Each of these methods has its benefits, drawbacks and environmental impacts. Seafood Watch has listed all oyster farming as Best Choice. How can a hydraulic dredge possibly fall into that Best Choice category? We go in-depth on that in Part 3.
After harvest, the farmers place the oysters into tanks of clean water, sourced from the oyster’s habitat. As they feed, the oysters clean themselves out. At the time of shucking, there’s nothing but clean salt water and tasty oyster in their shell.
As We Proudly Present… Your Oysters
When you enjoy an oyster, you’re doing more than just enjoying a great morsel. You’re celebrating a tradition of family businesses that sometimes date back generations. You’re enjoying the work of people around the world who spend their lives researching, learning, and toiling to bring you the best-tasting oyster possible.
Join us today at our thirteen-seat oyster bar! With our selection that changes daily, you’ll find some favorites. There will always be something new to try as well.