Oyster aquaculture
Aquaculture refers to the cultivation and rearing of aquatic plants and animals for food. Here at Bama Bay Oyster Farm, we rely on oyster aquaculture to grow our oysters in a sustainable manner.
Our oysters begin their journey at Bama Bay Oyster Farm as hatchery-reared seed, meaning they spend the early portion of their life stages in the controlled environment of a hatchery. This ensures that the oysters are being grown in the appropriate quality of water and receiving the necessary nutrients for optimal growth as they go through their larval stages and begin to permanently settle on substrate.
Once the oysters have reached that milestone and leave the hatchery, we place the seed in mesh bags where they are grown in the bay until they reach maturity. We utilize off-bottom culture methods where the oysters are grown in floating cages right below the water’s surface. These floating cages protect the oysters from predation and being buried by sediment. Off-bottom culture methods promote faster growth by increasing water flow and the availability of food. In addition, it allows farmers to manage and control fouling which is the natural build-up of algae and invertebrates (i.e. barnacles and mud worms) on oyster cages. Fouling restricts water flow through the oyster cage which can limit growth and cause stress on the oysters. Floating oyster cages allow farmers to control and limit fouling by periodically flipping the cages out of the water to air dry the gear and oysters. This method is effective because the oysters can survive out of water while the biological growth that caused the fouling cannot and will dry out.
As the oysters grow, we continue to monitor their growth and the surrounding water quality until they are ready for harvest.
Our oysters begin their journey at Bama Bay Oyster Farm as hatchery-reared seed, meaning they spend the early portion of their life stages in the controlled environment of a hatchery. This ensures that the oysters are being grown in the appropriate quality of water and receiving the necessary nutrients for optimal growth as they go through their larval stages and begin to permanently settle on substrate.
Once the oysters have reached that milestone and leave the hatchery, we place the seed in mesh bags where they are grown in the bay until they reach maturity. We utilize off-bottom culture methods where the oysters are grown in floating cages right below the water’s surface. These floating cages protect the oysters from predation and being buried by sediment. Off-bottom culture methods promote faster growth by increasing water flow and the availability of food. In addition, it allows farmers to manage and control fouling which is the natural build-up of algae and invertebrates (i.e. barnacles and mud worms) on oyster cages. Fouling restricts water flow through the oyster cage which can limit growth and cause stress on the oysters. Floating oyster cages allow farmers to control and limit fouling by periodically flipping the cages out of the water to air dry the gear and oysters. This method is effective because the oysters can survive out of water while the biological growth that caused the fouling cannot and will dry out.
As the oysters grow, we continue to monitor their growth and the surrounding water quality until they are ready for harvest.
ecosystem services of Oysters
Aside from the economic benefits associated with oyster aquaculture, oysters fulfill several important ecological services.
Oysters are filter-feeders which means they trap their food by passing water over their gills and transporting the trapped plankton to their mouth. While filtering the water for food, they also trap excess nutrients such as nitrogen and incorporate it into their shells and tissue. When there is too much nitrogen in the water, algae grows rapidly and if left unchecked, it can block the sunlight from aquatic plants and prevent photosynthesis. This phenomenon can lead to dead zones, in which there is little to no dissolved oxygen in the area and it is unable to support life. Oyster aquaculture has the potential to mediate the formations of these dead zones by filtering out excess nitrogen. Oysters can filter up to 50 gallons of water in a day which vastly improves the surrounding water quality.
Natural oyster reefs provide valuable habitat for diverse communities of marine fish and invertebrates. Juvenile oysters use chemical signaling to decide where to settle for life. As a result, juveniles tend to settle in areas where there are already adult oysters and they create complex structures. The resulting oyster reefs are rich with nooks and crannies which provide the ideal nursery for juvenile fish and invertebrates to hide in. In addition, the physical structure provided by oyster reefs also protects the coastline from wave energy and erosion.
Oysters are filter-feeders which means they trap their food by passing water over their gills and transporting the trapped plankton to their mouth. While filtering the water for food, they also trap excess nutrients such as nitrogen and incorporate it into their shells and tissue. When there is too much nitrogen in the water, algae grows rapidly and if left unchecked, it can block the sunlight from aquatic plants and prevent photosynthesis. This phenomenon can lead to dead zones, in which there is little to no dissolved oxygen in the area and it is unable to support life. Oyster aquaculture has the potential to mediate the formations of these dead zones by filtering out excess nitrogen. Oysters can filter up to 50 gallons of water in a day which vastly improves the surrounding water quality.
Natural oyster reefs provide valuable habitat for diverse communities of marine fish and invertebrates. Juvenile oysters use chemical signaling to decide where to settle for life. As a result, juveniles tend to settle in areas where there are already adult oysters and they create complex structures. The resulting oyster reefs are rich with nooks and crannies which provide the ideal nursery for juvenile fish and invertebrates to hide in. In addition, the physical structure provided by oyster reefs also protects the coastline from wave energy and erosion.
current threats
There are many threats currently facing wild and farm-raised oysters such as too little oxygen and storm damage.
Nitrogen and phosphorus are essential for life, however, too much in the environment can set off a chain reaction which ultimately decreases the amount of oxygen in the water. These nutrients are applied to crops as fertilizer to help accelerate their growth. However, the crops do not absorb all of the nutrients from the fertilizer and the excess nutrients enter our local waterways as agricultural runoff. The excess nitrogen and phosphorus in the water causes aquatic algae to grow rapidly and the environment is unable to keep up with the accelerated growth. These algal blooms can decrease the oxygen available in the water by blocking the sunlight from photosynthesizing aquatic plants. Without sunlight, the aquatic plants are unable to survive and begin to decompose, which further contributes to the low concentrations of oxygen in the environment. Once the oxygen in an area is depleted, it is unable to support life and is considered a dead zone. Oysters, among other aquatic animals, are threatened by these hypoxic (little to no oxygen) events.
Hurricanes pose a great threat to oyster aquaculture in terms of time and money. For every storm that passes through, we dedicate a lot of time towards preparing our farm for the potential impacts. We fill our floating cages with water so that they sink to the bottom of the sea floor. This laborious and cumbersome task ensures that our oysters will not float away when exposed to strong waves and storm surge. Even with this storm preparation, hurricanes can cause damage to our gear and farms. Unfortunately, storms are only intensifying in frequency and strength as we continue to experience the effects of climate change.
Nitrogen and phosphorus are essential for life, however, too much in the environment can set off a chain reaction which ultimately decreases the amount of oxygen in the water. These nutrients are applied to crops as fertilizer to help accelerate their growth. However, the crops do not absorb all of the nutrients from the fertilizer and the excess nutrients enter our local waterways as agricultural runoff. The excess nitrogen and phosphorus in the water causes aquatic algae to grow rapidly and the environment is unable to keep up with the accelerated growth. These algal blooms can decrease the oxygen available in the water by blocking the sunlight from photosynthesizing aquatic plants. Without sunlight, the aquatic plants are unable to survive and begin to decompose, which further contributes to the low concentrations of oxygen in the environment. Once the oxygen in an area is depleted, it is unable to support life and is considered a dead zone. Oysters, among other aquatic animals, are threatened by these hypoxic (little to no oxygen) events.
Hurricanes pose a great threat to oyster aquaculture in terms of time and money. For every storm that passes through, we dedicate a lot of time towards preparing our farm for the potential impacts. We fill our floating cages with water so that they sink to the bottom of the sea floor. This laborious and cumbersome task ensures that our oysters will not float away when exposed to strong waves and storm surge. Even with this storm preparation, hurricanes can cause damage to our gear and farms. Unfortunately, storms are only intensifying in frequency and strength as we continue to experience the effects of climate change.
CONTACT |
ADDRESSBama Bay Oyster Farm LLC
11951 Old Shipyard Rd Coden, AL 36523 |