Tuesday 7/28/15

New Larvae

• HC: 0
• SS: some
• NF: 0

Settlement

Set up an “overflow” setting system for larvae that do not go into the tile set-up. Silos (15 cm diameter, 20 cm height) with 180 micron screens are suspended in a tote with a draining outlet. 224 sized larvae are added into the silos along with 1-3 tablespoons of 450 micron cultch. An airstone is in the totes and water/algae is dripped into the silos. The water level is 13 cm deep, making the volume of water in the silo to be 2,296 cm^3 (equalling to 2,296 mL). I’ve been told that ~5 larvae/mL is good for this type of set-up, with no more than 10 larvae/mL. At 7 larvae/mL, the max to add to each silo would be 16,000 larvae.

Wednesday 7/29/15

Larvae tanks

• NF_Tank2_160 (224) -> 56,700 total: 600 for DNA, 15,300 to cultch set, 41,400 to NF_Tank2_160
• NF_Tank2_160 (100) -> swimmers only added back
• NF_Tank1_new (100) 0> swimmers only added back
• NF_Tank1_new (160) -> NF_Tank2_160
• HC_Tank2_160 (224) -> 15,937 total: 600 for DNA, 15,300 added to cultch set
• HC_Tank2_160 (100) -> swimmers only
• HC_Tank1_new (100) -> swimmers only
• HC_Tank1_new (160) -> HC_Tank2_160
• SS_Tank2_160 (224) -> 9,675 total, 600 to DNA, 9,075 to cultch set
• SS_Tank2_160 (100) -> swimmers only
• SS_Tank1_new (100) -> swimmers only (a lot on bottom)
• SS_Tank1_new (160) -> SS_Tank2_160

New larvae

• Some new larvae from all 3 populations

Setting Systems

To clean the tile setting systems, I first fill up a clean, empty 100 L larval tank with seawater and fill up a misting sprayer designated for setters with fresh water. I empty a tile setting tank over a 100 micron screen to catch the larvae that haven’t set yet. I put these in a tripour beaker with seawater and place the tiles in the 100 L tank full of water. I clean the tank with Vortex and fill it up as quickly as possible. Meanwhile, I spray the tiles and poultry wire gently with freshwater before returning the tiles and larvae into the cleaned tank. This took a little getting used to, especially figuring out how to minimize the time the larvae sat in the beaker as they would try to set on the bottom if they were in there too long.

I initially thought that the cultch set would be an experiment to see if the populations have differential success in the number of single oysters produced. Because of this, I cared a lot about having replicate silos, adding similar numbers of larvae to each, adding larvae on the same day, adding the same amount of cultch to each, and randomizing the order of silos. This led to me not using all of the 224s that I screened out, particularly from NF which somehow peaked in the number of 224s before the other 2 groups. I’ve since realized that to truly make it a viable experiment would take a lot of work (especially in the number of silos needed once I started screening them out by size) and that the main benefit of the cultch set is to grow up F2 oysters for future experiments. So I regret throwing out some of the 224s, but should still have enough for the project goals.

• NF: 15,300 added to Cultch_SetA
• SS: 9,075 added to Cultch_SetA
• HC: 15,300 added to Cultch_SetB