AQUA 353 Invertebrate & Algae Culture (3) (S) Theory and practice of aquaculture techniques for invertebrates and plants including identification, reproduction, hatchery and nursery operations, grow-out, health management, harvest, processing and marketing. Pre: AQUA 262 or aquatic ecology or instructor’s consent.
AQUA 353L Cultures of Invertebrates Lab (1) (lab) (S) Hands-on experience in hatchery, nursery and grow-out of aquatic invertebrates and algae. Pre: AQUA 353 or concurrent enrollment.
This first set of photos is from a laboratory activity where oysters were bred, as they would be in a commercial shellfish hatchery. The oyster used here is the oriental or pacific oyster, Crassostrea gigas. It was introduced from Japan in 1912, and is a favorite among many diners.
First, the oysters are cleaned with a brush.
This one is ready for duty.
Next, the oysters are immersed in a 30-degrees C water bath. This upward shift in temperature induces the spawning response whereby males release sperm and females release their eggs. These shellfish are gregarious breeders, the eggs and sperm are released together by all and mix together in the sea. New life results.
Professor Maria Haws (maroon-colored shirt) provides instruction to her students.
Oysters that do not want to cooperate with the 30-degree inducement can be opened with a knife. This kills the oyster, but one is assured to get the eggs or sperm out this way....Adam demonstrates.
Each oyster is placed into a small tub to collect its eggs or sperm. Through sampling and microscopic inspection, one can determine which are male and which are female. Each egg-containing tub is mixed with sperm from at least three males to ensure good genetic diversity. End result is millions of fertilized oyster eggs ready to grow-out and hopefully survive. Even with 25% survival, we can end up with several hundred million fertilized eggs.
Lab at Richardson's Beach Park.
A couple miles down the road south from the PACRC facility is a beautiful beach park.
Looking north-west towards Hilo (typical rainy weather that direction). Many sea turtles (honu) come here to feed each day.
As seen above, the south side of the park is an excellent area for snorkeling or just taking a swim. Walk five feet off shore, look into the water, and one can see a multitude of different fish, both large and small.
The different algal species were identified using a textbook as a guide.
Great place for a lab on a Friday afternoon.
A local fisherman (opportunistic hunter/gatherer) shows-off his catch, a couple of squid.
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