Life and death in TIC tanks. What's the DI when they swim up? Visiting a Maryland TIC classroom.2/27/2017 Sad news from Ludlow! Over the last week, all of Ludlow Elementary School's alevin died. I was visiting my daughter and her family in Bethesda, Maryland, (more about that later) when 3rd grade teacher Lisa Marks began to send text messages expressing her profound worry about persistently high levels of nitrite (5 ppm). This was strange because her ammonia hardly got above zero and was never higher than 0.25 ppm. (This is Lisa's second TIC year, and, having been very successful last year, she was doing everything just the same as she did previously.) Lisa's fish looked bad and eventually began to died in large numbers. On Thursday, she was down to five fish. By the time students returned to school today, they were all gone. Very tragic! I had a lot of contact with Maryland TIC coordinator Chuck Dinkel while this tragedy was unfolding and since. We are all baffled that Lisa's nitrite was so high even though her ammonia wasn't high at all. There was a point several weeks ago when Lisa noticed black slime on her breeder basket. She cleaned it of course, but we are now wondering whether the slime may have caused the problem that her tank experienced. Tomorrow afternoon, Chuck, Lisa, and I are scheduled for a conference call. We will try to get to the bottom of this mystery! One suggestion that Chuck had is that in a similar situation, we may want to use something called Amquel Plus, a product designed "to neutralize ammonia, nitrites, nitrates, chlorine and chloramines." Years ago this water additive was a standard part of the Maryland TIC kit but was dropped once Special Blend and Nite-Out II began to be used. Chuck believes that the problem with Amquel Plus is not its use but its overuse. If used when the tank isn't really in crisis, it can interfere with the natural and highly desirable nitrogen cycle. But if in the future another Vermont tank behaved like Lisa's did, with persistently high nitrite levels and fish that looked severely stressed, I would certainly advise treating the water with Amquel Plus. After our conference call, we'll decide how to move forward. Already three southwestern Vermont schools have volunteered to donate fry to Lisa's class, and Tom Jones, of the Fish and Wildlife Department, has approved the transfers. They're swimming up all over the state! But at what DI?? Here are excerpts from three e-mails I received this morning. Jason Gragen, of NewBrook School, sent this report. Our brookies started to feed on Thursday, February 23. Although we were on school break, I checked on them every day of the vacation because I figured they would be approaching the swim-up stage. The ammonia, nitrate, and nitrite levels in the tank are currently looking good. We're running at 51.8 degrees. I got this from Rutland Town School's Brian Crane. My little ones did well over the weekend. It looks like I have two pinheads and a couple of deformities that are hanging on. They are crazy active and some have got caught on the net jumping up. Almost all have swum up now. Should I drop the basket this week? I get it's a long way for them. Maybe I could put a second basket in too. Its crazy how fast this happens! Here was the answer I sent Brian: I wouldn't drop the basket yet. As you say, it's a long way, 21" in a 55-gallon tank, from the bottom to the surface. I'd keep them in the breeder basket for another couple of weeks to fatten them up before releasing them into the tank. When they get ready to release the trout, some teachers tip the basket and leave it at an angle. That way those that want to swim out of the basket can and those who want to stay behind for another few days can as well. Make sure your filter intake is covered with netting or mesh. And Audrey Halpern, community volunteer at the Albert Bridge School, provided this update. Our trout tank is doing well we seem to have made our way through the high nitrite part of the nitrogen cycle (5 ppm) and our nitrates are rising with falling nitrites. Our swim-up occurred last week during the vacation week, which meant a lot of school visits, but that was okay. Our DI was only at 90.43 when we had 25% swim up. We had about 100% feeding three days later at 94.41 DI. So our calculations to have swim-up happen this week when we were back at school didn’t quite work out. I did have the warning of the disappearing yolk sac, so I thought we were probably ahead of the calculated DI. The fry are active and happy in their increased light levels. We do have quite a number of escapees that are loose in the tank because they got over the edge of the breeder baskets. I can’t decide how often to chase them with the net to put them back so they get more feed. I have to admire their spirit. It keeps it interesting. So what was the DI when your fish swam up? I think we're finding that our brook trout develop faster than the chart we've been using would indicate. Several schools have reported that their fish began to swim up, not at 100% DI, but when the alevin reached a DI of 90 or so. The chart we've been using to estimate how much each "degree day" contributes to a trout's development was provided by Roxbury fish hatchery supervisor Jeremy Whalen, and it's fairly old. In fact, Jeremy isn't sure which trout species it was developed for, so it would be extremely helpful if many more teachers can provide the kind of report that Audrey did. Visiting a Maryland TIC classroom As I mentioned above, while in Bethesda, Maryland, last week to spend 10 days with my younger daughter and her family, I made contact with three 6th grade teachers who are doing TIC at North Bethesda Middle School. Given that the school is within walking distance of my daughter's home, I couldn't resist asking if I could pop in to see their TIC work. NBMS is a highly regarded, rapidly growing school of 1,200 students in Montgomery County, Maryland. TIC is pursued there by three 6th grade teachers: Eric Elmer, Maria Lutchenkov, and Susan Martin. I arranged to visit Eric's class shortly before some of his students were about to perform the daily tank inspection and water testing. Eric and his two colleagues collaboratively use one tank that is set up in the hallway outside their rooms. They and other Maryland schools raise rainbow trout, and NBMS, like other schools in their state, keeps its tank at approximately 54 degrees. Here's a photo of their tank. One of the first things I noticed when I reached the corridor where Eric's classroom is located was the beautiful mural that covered the window behind the tank. I learned that an art class painted the very large piece of blue paper that was probably 6' high and 16' long. Students first drew various decorative elements above and below the waterline: hills, trees, seaweed, etc. Then they cut out and colored fish, ducks, and other creatures, which were then pasted on in appropriate locations. The whole mural is also functional in that it screened the tank from daylight. I also got to observe the tank inspection and water testing process. The team assigned to do the testing was under the direction of a girl who had had a bit more training than the other students. (Normally two student leaders direct each day's activities, but one of the student leaders was absent the day I visited.) The 6th graders are trained by 8th graders who did TIC two years ago. The students seemed both very competent and quite focussed in their work. Here's the water testing team in action. As I was about to leave the classroom, I noticed a collection of fishing rods in the corner. Obviously, as part of their TIC activities, NBMS students are also given the opportunity to learn how to cast and fish. Lucky them!
It was fun to see what a TIC program looks like in another state.
0 Comments
Leave a Reply. |
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
Categories |