Redefining the Classroom

Atlantic Salmon Growth

Below are pictures of Atlantic Salmon eggs as they grow.

Collecting Milt

Collecting milt (sperm) from male salmon.

After we had expressed the eggs from the female and into a container. We then add milt or sperm to the eggs, add water and (this stage or period is call the sensitive or green egg stage) mix.

These eggs were collected on November 13th.


The eggs are placed into an egg tray and held until they (they go through the sensitive stage, eyed egg stage then the sac-fry or yolk-sac stage) are ready to feed.

If you look closely, you will see black spots and those would be the eyes. The eggs had eyes for about 2 or 3 weeks now.

You can see the backbone on them also if you look hard.

White egg are dead eggs.

The water temperature is around 47°F.


The eggs started hatching the week of January 14 and finished up by the end of that week.

These are called sac-fry.

The yolk is their feed (while they are sac-fry) and they absorb it as they develop.


These are sac-fry from Jan. 26.


These are sac-fry from Feb. 2.

The sac-fry are starting to darken up and the yolk is getting smaller.

Once the yolk is absorbed they will then begin feeding. This is about 2 to 3 weeks away.


These are sac-fry from Feb. 12.

The sac-fry are darker and are now laying more upright (not laying on their sides as in the past). They have about 30 % (roughly) of their yolk left.


These are sac-fry from Feb. 19.

Here is the latest pictures of our Atlantics. You can see a lot of the yolk is gone and next week we will be moving the sac-fry into our raceways (fish containers).


These are sac-fry from Feb. 23.

From the egg trays, the sac-fry are moved into the raceways.

We will start feeding them later this week.


These are swim-ups (previously called sac-fry) from March 2.

These fish are now feeding.


These are swim-ups from March 16.


These are swim-ups from March 26.


These are the swim-ups as of April 2nd.