Issaquah Salmon Hatchery Volunteering

Today we volunteered at the Issaquah Fish Hatchery separating the dead and unfertilized salmon eggs from the viable eggs. The chinook salmon eggs are now 4 weeks old and about the size of a pea. The viable eggs were salmon colored and slightly translucent, so you could see two little tiny salmon eyes inside. If you looked at the eggs patiently, you might see one of the little fish squirm around inside its egg. The bad eggs were milky white, hard, and some had a dark fuzzy mold or fungus on them.

All of the eggs first passed through a mechanical separator, which separated the eggs by shooting a laser through them and if the laser light did not pass through the egg to the receiver on the other side, the egg was deemed “bad” and deposited into the “reject” bucket. Conversely, if the laser light passed through the egg, the machine assumed it was a viable, translucent pink egg and deposited it into a second “keeper” bucket. As you might imagine, there were some bad eggs that were mistakenly deposited into the “keeper” bucket (false positives) and also some good eggs that were mistakenly deposited into the “reject” bucket (false negatives). So, as a volunteer egg picker, we sifted through the contents of these buckets and plucked out the bad eggs that were accidentally deposited into the good-egg bucket and picked out the good eggs that accidentally ended up in the bad-egg bucket.

As you can see from the photos below, we used little calipers that looked like toast grabbers or barbecue tongs to pick up each egg one by one.