How Oyster Spat is Made in an Oyster Hatchery. European Flat Oyster, Belon

I got a call from Joe tell me it was time  to settle the European Flat Oyster larvae.   European flat oysters are also called  Belon and it's a native oyster of Europe.   Interestingly it's actually closely related to our  Olympia oyster. Quickly I headed to the UC Davis   Bodega Marine Laboratory in Bodega bay California.  We're going to rush inside to the oyster hatchery.   I wish I had time to give you a tour of the lab  and show you this awesome rockfish aquarium but   Joe's already starting to empty the tank of  the oyster larvae. We got here just in time. Ss we shine a light into the culture tank you  can see millions of larvae swimming around.   We know they're ready when the larvae  start settling to the bottom of the tank   and begin probing the surface with their  foot to find a substrate to attach to. While joe is busy emptying  tanks we need to ready the   downwellers and fill our sumps with phytoplankton.   When you have an oyster hatchery you better be  good at farming microalgae to feed your oysters. Once we've filled our buckets, Sam will make sure  there's enough food in each of the downwellers. We also want to make sure that there  is plenty of oxygen in the downweller.   The aeration also serves to mix the microalgae  and keep it in suspension. A downweller is   designed for water to gravity flow down  through the system, in this case a sieve.   Oyster larvae will be needing substrate to  attach to but in a downweller you would use   a variety of sizes of crushed shell. We're going  to use a fine powdered shell. Hard to believe   that each grain of sand will end up supporting  a single oyster larvae. Now before you can go   on adding oyster larvae to the downwellers there's  a whole bunch of busy work you need to do. Here Joe   is checking to make sure there are no air pockets  before adding the larvae. That would be lethal. We're ready to add the powdered oyster shell. Bet you forgot about our tanks? They  should be close to emptying by now. All those dark specks are baby oysters. After our culture tanks have been  emptied Joe's going to make sure   that all the detritus and debris gets  pushed through the 150 micron sieve.   This process may take some time but  this is the last chance to really   make sure that you have a clean sample  before adding them to your downweller. Once you've added the larvae into the bucket  and a set amount of water, you'll calculate a   concentration to ensure the right amount  of larvae are put into each downweller.   To determine the concentration of oyster larvae  we're going to use this graduated cylinder as   a plunger to mix our sample. We will take multiple  measurements and record the concentration under a   microscope and then take an average. It turns out  we have an abundance of oyster larvae so we're   going to select only the largest, healthiest oyster  larvae and remove anything less than 230 micron. At this point we're going to repeat the process,   filter the sieve one last time, add our  water, and determine a final concentration. And now the moment you've been waiting  for! It's time to fill the system. How many of you would have guessed that  there's 50,000 baby oysters in that beaker? Joe and Sam will go on to systematically  fill each of the downwellers   and they will do one last check just to make sure  they're into any large air bubbles in the downwellers. Larvae will remain in the oyster hatchery until they reach two to three millimeters and now   referred to as oyster spat. At that point they'll  be transferred into a FLUPSY. To find out what is   a FLUPSY and follow these oyster larvae into  the field you'll want to watch this next video!

Channel: This Is Aquaculture

Views: 20,697

Keywords: oyster, oysters, aquaculture, oyster farm, oyster harvesting, oyster farming, oyster processing, oyster hatchery, how to farm oyster spat, how to farm oysters, how oysters are farmed, how oysters are made, how to make oyster spat, spat on shell, uc davis aquaculture, california aquaculture, low trophic aquaculture, sustainable shellfish aquaculture, european flat oyster, ostrea edulis, flat oyster, belon oysters, what is shellfish, microalgae, shellfish farm, ocean aquaculture

Id: wZEuvpKrRhA

Length: 4min 45sec (285 seconds)

Published: Sun Sep 19 2021