For some, swim-up starts already! Bob Wible told me last Thursday that he expected that the alevin of at least one of his tanks was going to hit the "swim-up" stage tomorrow (February 8). Here's what he said: Hi Joe, I have a tank at the South Burlington high school sitting at 56 degrees. A few alevin are giving swim up indications and will probably start feeding early next week. Very exciting. Bob In a separate e-mail, Bob told me that he believes the DI at SBHS will be 100.12 tomorrow. As far as I'm aware, very few other schools have kept their tanks that warm, so most of you are probably several days if not several weeks from the "swim-up" stage. Nevertheless, it will likely be the most important next development to arise, so let's talk about what you need to do to be ready for it. For the rest of you As your Cumulative DI approaches 95, you should remove the front and top foam insulation (this will help stimulate the swim-up instinct), and you need to become very attentive. Look for evidence of alevin swimming to the surface. (You may want to revisit the above-mentioned "Idaho TIC document.") Alevin require careful monitoring at this stage and should be inspected several times every day, including weekends and school breaks. If some fry start swimming up, provide the tiniest pinch of food. Remove whatever is not eaten after ten minutes. When fry have begun eating reliably, you can feed them as often as five times a day, but always just the tiniest pinch. Spotting when alevin/fry are swimming up to the degree that they should be fed isn't easy for those still fairly new to TIC. Here's a technical bulletin from the TroutLodge hatchery, which provides eggs for the Maryland TIC program, and here's some advice (from Marshall Brown, a Maryland hatchery biologist) that Chuck Dinkel shares with the Maryland teachers. It’s my experience that small percentages of fish will begin to swim up continuously over a period of 3-5 days regardless of the tank being used for culturing. I begin to supplement feeding when approximately 25% are up [emphasis added] and gradually increase feed amount as the percentage increases. Below is an image from the Idaho TIC program that helps teachers tell when their alevin might be ready to "swim up." Here is a link to an 8.5" X 11" version of that document that will be easier to read. And don't let the bottom of the net breeder get too dirty! (More on this later.) Genetic mutations at three schools Every year a certain number of eggs will produce abnormal alevin. So far this year year three schools have sent me pictures of their genetic mutations. I've inserted their pictures below. It would be interesting to have students research how often genetic notations like these occur in trout and other fish species. How often do they occur in humans? Salmon eggs! Sixty-eight of our 70 tanks this year are raising brook trout. The other four, all located in northern Vermont, are raising landlocked Atlantic salmon. SIC is actually quite different from TIC in a number of ways, and that starts with the appearance of the eggs. Chris Murphy, of North Country Union High School, sent me these two photos of his class's salmon eggs. Look carefully to spot the lone hatchling in the lower photo. Here's what he said: Hey there Joe, One thing that I noticed when reading your blog was the amazing difference in appearance between the brook trout eggs and the landlocked salmon eggs. I included some pictures of our salmon eggs that shows the color difference. One picture has our first hatched alevin, it stands out amongst the unhatched eggs - I thought it was a neat shot. I'll be sending more pictures as time goes on! Chris Murphy TIC national quilt project underway Yesterday, Tara Granke, national TIC coordinator for Trout Unlimited, sent me the list of the 46 schools across the country that signed up to participate in this year's quilt project. I was pleased to find the following eight Vermont schools on that list:
Founders School TIC blog I know that many teachers are use the Internet or Google resources to publish and share your TIC work with parents and other members of the school community. See especially the student blog comments. Here's a link to the TIC blog of Founders School: St. Albans City Elementary Web page And here's a link to John Cioffi's St. Albans City Elementary School TIC Web page. Great close-up shots Here are four close-up photos sent in by Danielle Levine at Schoolhouse Learning Center. They were taken by one of Danielle's 4th graders. Keep up the great work!!
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Joe Mark, Lead Facilitator, Vermont Trout in the Classroom
In June 2012, I retired after 40 years in higher education, having spent the last 32 years of my career as dean at Castleton. One of the first things I volunteered to do in retirement was to work with Jim Mirenda to help the Dorset School, where his kids and my Vermont grandkids attend, start a TIC program. Gradually that commitment grew into my current role, which is both demanding and highly rewarding. Archives
June 2017
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