A combination of over-harvesting and diseases introduced by Pacific oysters have taken its toll on the Bay oysters since the 1960's. The oyster gardening program was developed to enlist citizen assistance in raising oysters and replenishing the oyster population. We will grow these babies for 1 year at which time those that survive will be mature and able to reproduce. (The goal is to produce oyster baby-making machines.) The mature oysters that we return to the Foundation next year will be planted on one of over 100 protected oyster bed reefs that have been started in the Bay, safe from harvesting, to allow the oysters to reproduce and their offspring to be spread throughout the Bay.
I'm not exactly sure what we were expecting when it was time to receive our 1000 oysters after the seminar, but the small net bag that fit in my hand was not it!
Baby oysters are very, very tiny.
As you can imagine, oysters this tiny are tempting food for a lot of predators. As such, we have to provide a habitat that allows the oysters to be suspended in the water column with room to grow, but protected from blue crabs and the like. So, we opted for the "mesh bag" habitat, which is then attached to floats on each side to suspend the oysters in the water. Here you can see Rob attaching the floats to each side of the mesh bag:
Once the floats were attached, as instructed, we placed the oysters in the bag...
gave the bag a good shake to spread out the baby oysters and maximize their exposure to the water (which provides them food and oxygen)..
and tied off the top to keep them inside the bag and potential predators outside:
Once they were safe and snug in their new home, we placed them in the water and secured them tightly to our pier.
Oysters can pretty much care for themselves - as we were told, growing oysters is really just one step above having a pet rock! We'll need to flip the float once each week, clean off any algae and sediment to maximize the oysters exposure to the water (and their growth), and check the bag for baby blue crabs that sometimes get inside and eventually could grow big enough to eat the oysters. (As they told us, if that happens, we'll have no oysters left but one big happy crab in our bag!)
A few fun facts we learned at the seminar:
- Oysters can be out of the water for several hours or even a day, but if you put them in a bucket of water, they will die very quickly because they will deplete the oxygen in the water.
- Oysters can survive being frozen in ice in the winter, but they can die if exposed to the winter elements outside of the water.
- Oysters reproduce externally (the egg and sperm are released into the water and hopefully meet up).
- Oysters are either male or female, but they can change sex during their life cycle.
- Oyster shells are an important part of water habitat, so returning shells (even sans the oyster) is good for the Bay. Oyster shell driveways were very popular (but not good for the Bay) and we still see the remnants of the old oyster shell driveway at Glenlochan.
A final look at our oyster farm, below. Stay tuned as we report on survival and growth rates!