CHILDREN & THE WATERSHED

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Some of the trout are very dark in color and some are almost see through.

From: Dawn Schummer (Copper Trail), Volunteer David Rupprecht

Some of the trout are very dark in color and some are almost see through. I tried looking up why, but could not find anything. Do you know?  They will be testing the water again on Wednesday, so I will take pictures of them doing their different jobs.  We have only 4 eggs that did not hatch. We have one fish that looks like it’s spine is deformed, but he is swimming around crazy. We have 3 still alive in the hatching net, but they are not looking too great.

Answer: DJ Zor

As for the color variance, I haven’t a clue. Maybe due to how long it’s been since they hatched? Maybe it’s due to how much light exposure each has received and when exposure becomes more constant they’ll all adjust the same???

The one with the deformation likely won’t make it and definitely wouldn’t in nature. The not so great fish may get strong may not. User discretion on when to cull. The problem with dead fish is decay causes chemistry problems. There’s a balance with food and poop that’s pretty regular, a dead fish adds lots of decaying matter quickly and that upsets the balance.

alevins in the net that appear to be dead

From: Alison Messner (Morristown Elementary, Volunteer: Greg Stock

Our only dilemma are the alevins in the net that appear to be dead. We start to remove them, but then they move around. This has initiated some interesting discussions. We talked about how these weak alevin would have been killed by predators, but they survive in the safety of our tank. At least 2 have never fully stretched out to the shape of a fish, and they just twirl around. Any advice?

Answer:  DJ Zor

This has actually been a pretty common question this year and something we will try to address in our manual next year even though it takes some discretion in my opinion. What I’ve been telling other teachers and volunteers is to use your best judgement and give them a chance to make it on their own. I kind of like the “sink or swim” metaphor. The risk is leaving the weak/sickly fish in so long that they cause a negative impact on chemistry when they decay, which starts right away after death. My other concern, and I don’t have any evidence to support it, is that weak fish may get eaten and encourage further cannibal behavior. We lost a lot of fish in our Cave Creek school last year with no evidence of where the dead fish went. One theory is that they were eaten. Like I said, no evidence, just a possibility.
Thanks for the great news that many are hatching successfully and children and parents are excited.