[Some of what follows appeared in a 11/15/16 blog I wrote. I've also broken this piece up with three nice pictures of students at Bellows Free Academy. Thanks, Melinda!] Predicting and controlling when swim-up happens At this fall's TIC workshop, we discussed two of the biggest challenges of raising brook trout:
when the fry swim up. A future post will talk about how to keep the breeder basket clean. "Swim-up" is a stage that occurs when alevin become fully developed. Prior to that point, alevin have been living on the bottom of the breeder basket, but when they approach being 100% developed, they start making tentative movements towards the surface. Experienced fisheries biologists like Roxbury hatchery's Jeremy Whalen can recognize the fairly subtle cues that indicate the alevin have reached the swim-up stage (when they'll be called fry). But TIC teachers and volunteers, who observe only a comparatively small number of alevin and who raise trout just once a year, usually find it very difficult to spot the telltale signs of the swim-up stage. As a result, we need to use data to predict when fry will swim up. And for this, we've created a data entry sheet and a special "swim-up calculator," which you can find here. (You can also find this spreadsheet in a folder called "Calculating Development Index," which is in the TIC Google Docs Collection, available from the TIC Resources page of this Web site.) Thanks to the efforts of Lorena Schwarz and with some help from Castleton University statistics professor Abbess Rajia, this new file is much improved over the one we demonstrated at the workshop. A quick note about the Excel file attached to the link above: it contains four worksheets. The first provides instructions, the second is used to PREDICT swim-up and to record water temperature data, the third will allow you to DETERMINE or CONTROL when the alevin swim up, and the fourth you won't need to use, it simply allows a formula to perform a "lookup" function. Below I've included a screenshot of the four tabs that give you access to the three worksheets you'll need to use. Predicting the swim-up stage Development is a function of water temperature and time. With each day that hatchery or tank water is at a particular temperature, a constant is added to the previous day's cumulative Development Index (DI). This chart (below) shows the relationship between temperature (in tenths of a degree, which appear at the top of the columns) and the constant that is to be added to DI. So, for example, at 49.3 degrees, the value of 1.146 is added to whatever the cumulative DI was on the previous day. When schools got their eggs earlier this month, you should have entered the date you received your eggs into cell B4 in the "mm/dd" format, e.g., "01/06" would represent January 6 (image below). Either hatchery staff or your egg deliverer will be able to tell you how developed the eggs are on that day, that is, what their Cumulative DI is. This number is very important and should be entered into cell C5 of Sheet B. From that point forward, all you needed to do is enter the daily water temperature into the cell in Column B that corresponds to the correct date. The spreadsheet will automatically calculate the new Cumulative DI. It is important to enter water temperature data for every day, including weekends and school breaks, even if you haven't checked the tank temperature. For those days when you don't/didn't visit the tank, estimate (or "interpolate") the water temperature. So if the temperature was 51 when you left on Friday afternoon and it was 49 when you returned to the classroom on Monday morning, enter a temperature of 50 for each of the weekend days. And don't let the bottom of the net breeder get too dirty! (More on this later.) Controlling the swim-up stage But what happens if you realize that swim-up is likely to occur when your school is scheduled to be on vacation or at a time when, perhaps because of a conference trip or personnel leave, you won't be able to diligently monitor your fish, looking for those subtle signs of the swim-up stage? Here's an exchange between teacher Ted Nathanson (of East Montpelier Elementary School), volunteer Shawn Nailor, and Roxbury hatchery supervisor Jeremy Whalen: TN to SN: Hope you had a nice weekend! Wanted to give you an update. On 1/11/17 we had 2 eggs that hatched. When I got in this morning we had 6 more over the weekend for a total of 8. Now at 3 o'clock, we have almost 30 total. They are going crazy! The water temperature is at 52.2 and the water chemistry is all normal. Our pH is at 8, is that an ok level? Should we stay on track with the water temp of 52? Thanks! SN to JW: Any suggestions or is this 'normal'? JW to SN: At 52 degrees, this is normal. They must be pushing 58 DI at this point. If he stays at 52, though, the fish will start feeding before or during the next break. If his goal was to start feeding after February break, he needs to cool the tank off. (I later learned that Ted's DI was 53.67 on 1/16.) SN to TN: I sent along your email to Jeremy and here's his reply (above). TN to SN: Thanks for looking into that. Our last day before break is Feb 24th and we don't return until March 8. When I use the swim-up calculator and set the swim up for March 9th, I need to get the tank down to 46 degrees. Our break is longer than normal and starts later than most schools with presidents week off. Should we still shoot for swim up after break? Does this sound like a good plan? So, sometimes you have to take control of your tank and its temperature to ensure that you're around and able to give lots of attention to your fish when they start to swim up. That's when you need to use the third tab of the Excel file we discussed above (see image below). When you click on that tab, it will take you to this "calculator" form. As long as you've been maintaining the DI total (by keeping up the "Temp. entry and DI record" spreadsheet, as described above), you will be able to enter the three data elements called for in Cells B5, B6, and B7. Once you've entered the third of those ("Total DIs as of today"), you'll find out what temperature (it'll appear in B12) you need to set your tank at in order to have your fish swim up on the day you've chosen.
If the specified temperature is more than five degrees lower or higher than what it currently is, you might want to step your tank down (or up) more gradually. In that case, I'd recommend that, after your tank temperature has reached the target number, you redo the calculation (using the Swim-up calculator a second time) with the new numbers for DI and dates. This will permit you to fine-tune the temperature setting. In a future post, I'll discuss breeder basket cleanliness as well as some tips for identifying when alevin are approaching the swim-up moment.
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What are the benefits of TIC? You tell me. Here's a wonderful report I recently got from one of our terrific Vermont TIC teachers: I have to tell you about one of my students. He is a very reluctant learner, comes from a long line of family members who don't have anything nice to say about education, and rarely smiles. Yesterday when he was about to be picked up, he ran outside and begged his mom to stay later until the eggs were officially in the tank and we were done adding the NiteOut II and Special Blend. She let him...she let him! His wanting so much to stay with me and his mother's recognizing how important that was to him was worth the whole experience, regardless of what happens from now until May (well, sort of!). If you look at the picture of our community volunteer talking to the kids he's the one in the red shirt. Note the SMILE on his face! That's a smile I have rarely seen. As you encounter stories like this that illustrate the benefits of TIC, please share them with us. Here are some new TIC photos provided by the team--Syl Stempel, Shawn Nailor, Gloria Nailor, and Mike Bard--that covered 227 miles last Friday to deliver eggs to Cambridge Elementary, Cold Hollow Technical Center, Eden Elementary, Hyde Park, and Waterville Elementary schools. Chart hatching data Many of you have experienced some early egg hatches. I've got a suggestion for you: keep good track of those data and then have your students turn them into a line or column chart. I'd love it if you'd then also send those charts or images of them to me. That way, we'll have better information to share with next year's teachers. In fact, if I can aggregate data from all submitting schools (especially if you'll also send me temperature data), I can generate a table of the patterns of hatching statewide. That will help future teachers decide whether their hatch patterns are "normal" or not. Another idea is to have your students research rates of premature births in human ("gestational age at birth"). They could then calculate prematurity rates for their trout and then compare them to human rates. Here's an example of the kind of data on human births that you can find online. You can find a larger version of this image here. The whole report from which I got that table is available here. Good work at The Schoolhouse Learning Center This afternoon Danielle Levine submitted this brief report: Here is our data chart so far. Students are loving doing the testing. We observe the egg under a microscope and allow every kid to look once a week. In the 4/5 class, they are learning about how to do the testing, the ideal conditions for a trout and the chemistry. In the 2/3, they compared the trout egg to a chicken egg. In the K/1, we made 3-D models of the egg for each kid to take home. They can now identify the yolk, eyes, backbone and brain. Good fun! Here's a link to a table of Danielle's data to date. (Below is the most critical excerpt from that table.) How do these numbers compare to yours? And below the table are some photos of the egg models Danielle's K/1 kids made. Nice, huh? Report on SIC While we have 71 tanks in Vermont raising salmonids, 68 of those raise brook trout. The other four raise landlocked Atlantic salmon because those schools are located near rivers that support spawning runs of salmon, either from Lake Champlain or from Lake Willoughby. Here's a brief report from Chris Murphy, of North Country Union High School in Newport, Vermont. I did want to send a quick check in an update. Our 200 salmon eggs were delivered right before the new year. A majority of them have hatched and things are going very well. The only issue that I faced was a small one-day outbreak of a little white fungus on a couple of dead eggs over a weekend. Luckily that's been removed and taken care of quickly. And fortunately we finally received our testing supplies that we ordered, and I am doing daily tests and recording that data! Whew!! Hundreds of miles and dozens of volunteers later, before kids left school on Friday, January 6, most of Vermont's TIC schools had their eggs. In southwest Vermont alone, eight of us delivered 3,150 eggs to 17 classrooms. It was great fun! Here are some pictures of that day (but I hope I can add more shortly. Send them in). Egg origin story Here are some facts about the eggs you received:
Weird eggs, early hatching, and fungus In one early report relayed by Addison County TIC volunteer Doug Zehner, Melissa Muzzy, of Vergennes Union HS, wondered whether this photo was of a set of Siamese twins. I'm not sure, but when I zoomed in on the conjoined pair of eggs, I though it looked like it might be two fairly normal eggs connected by fungus. Lisa Marks, of Ludlow ES, had what may have been the first hatchling of 2017. Here is a picture of her new baby. See the tail poking out in the center of the picture? By the way, whenever an egg hatches, the shell is left behind. This should be removed using a pippette or turkey baster. When Bob Wible asked Jeremy about such an early hatch, here's what Jeremy said:
An egg hatching at 40-41 DI is not uncommon. You will see some early hatching. When the DI hits 58, we would expect 100% to be hatched, but some will start hatching much sooner than that. Along with looking for and removing dead eggs, you should also vigilant about fungus. When I delivered eggs to Fair Haven Grade School on Friday, it appeared to me that four eggs had little patches of fungus on them. I told teacher Amy Wright that I didn't think these had to be removed immediately, but I suggested that she monitor those eggs. Should the fungus grow or spread, then the eggs should be removed. Keep track of data! At this point in the TIC cycle, you or your students should be entering data into two spreadsheets every day:You'll no longer need to use the first of these once your fry are feeding, but the second should be used right up to Release Day. Web site statistics This past week, our Web site received its most traffic ever. Here's a chart of the "pageviews" for the week. (These were generated by 114 unique visitors.) It's happening! Yesterday several schools received their eggs. Dozens more will be getting them tomorrow, so there's no turning back. Here's a picture of the tank at Poultney High School, perfectly set up and at the right temperature (45 degrees) but lacking living matter, those precious eggs. Especially for those of you who are new to TIC, here are some final instructions.
Bob Wible and I had essentially similar opinions: Keep an eye on it. It might be dying, but the evidence of that isn't yet conclusive. (See page 26 of the manual.)
If you don't know when your eggs will arrive, contact your community partner or regional TIC liaison ASAP. I don't know who all the community partners are, but here's a list, by county, of TIC liaisons:
Above, four nice "opening day" photos from Browns River Middle School. Equipment failures and routine maintenance While at a family gathering in Bridport on New Year's Day, I got a concerning e-mail from Archie Clark of Benson Village School. His one-year-old Fluval filter, which performed flawlessly last year and was running fine before the break, wasn't working when he went in to check it. On Monday, through e-mails and phone calls, we engaged in collaborative trouble-shooting to no avail. So on Tuesday, I visited his class to get a better sense of the problem and its possible causes. Long story short, after a lengthy call to the manufacturer on Tuesday, I decided the our only choice was for me to run into Rutland to get a replacement filter--fortunately they had one, and it was even on sale! This morning, Archie reprted that everything was A-OK. Yesterday, I also learned of a central Vermont school that had its chiller die recently. Why do I bring this up? The Fluval customer support representative peppered me with questions about whether Archie had been following the routine maintenance procedures detailed in the manual. I didn't know what Archie had been doing; but I suspect that, as long as their equipment seems to be working fine, many teachers don't think to check the manuals to see what the "best practices" of routine maintenance are. We can't say whether these two breakdows would have been prevented by maintenance, but these experiences can serve as a reminder that there is some minimal maintenance that we ought to be doing periodically. I don't want your filter or chiller to be the next to go! Good luck!! I hope that you've either got your tank set up and insulated or that you plan to do so in the next few days. Here's a picture taken Tuesday evening of Emma Vastola, of Mount Holly School, right after she and community volunteers Kathy Ehlers and Gordon Batcheller finished setting up her tank.. Once you've got everything tested and have established that your chiller can cool the water to 45 degrees or so, you can set the chiller at a more reasonable, less energy-consuming, temperature, e.g., 60 or 65 degrees. Make sure you keep your tank wrapped in its foam-board "blanket" both to insulate it and to protect it from light. Especially when the water is warmer, light can promote the growth of algae, which wouldn't be good. Please reread Chapter 4, Preparing and Transitioning Eggs, pp. 25 & 26 of the Maryland TIC Manual, except that you won't be setting your tank to 52 degrees at this point. We will raise it to that gradually after you've gotten your eggs, but on the day in early January that your eggs arrive, we want your water to be fairly close to the temperature of the water at the hatchery, at least within five degrees of it. On or about December 20, I'll let you know what the water temperature is at the Roxbury hatchery. (It was a chilly 39 degrees this morning!) You should then set your chiller to that much lower temperature and keep it approximately there until you get your eggs. Here are some photos taken of the Moretown TIC tank and students and of the TIC team and set-up at Camels Hump Middle School. Egg delivery plans A few TIC teachers plan to pick up their own eggs at the hatchery, but the vast majority will be having their eggs delivered to them by a TIC volunteer during either the first or second week of January. In most parts of the state, the TIC regional "liaison" is organizing a schedule for those deliveries, and in the regions with numerous TIC schools, getting out all the eggs will require assistance from other volunteers and, perhaps even, a tightly coordinated schedule of hand-offs and deliveries. (Contact your local TIC liaison or community volunteer to confirm the date and time of egg delivery.) When all goes well, the TIC team's performance on egg-delivery day is as beautiful as an Olympic gold-medal-winning relay race! Now we just have to worry about the weather. Here's what our plan looks like for getting eggs to 17 of southwest Vermont's 20 TIC schools. Modify those breeder baskets! As Bob Wible and I discussed at the TIC workshop, it's highly desirable to modify the breeder baskets that we buy from ThatPetPlace.com. There are two problems with the standard commercial breeder baskets:
Below I've provided two photos of what Bob's modified mesh bag looks like. Numbers update
In the last post I reported that 67 schools would be participating in the TIC program this year, up from 37 last year. Well, in fact that number has inched up in the last two weeks. We now have 69 schools in virtually every corner of the state participating (and 70 tanks). These schools are being supported by 93 teachers and 29 volunteers. I'd say that's pretty impressive! Order your eggs now! Recently Tom Jones, of Vermont Fish and Wildlife, sent out a list of schools that have requested eggs. I forwarded that list as an e-mail attachment to all Vermont TIC participants on November 27. If you weren't on the list, please order your eggs ASAP using the application available in this Google Docs folder Detailed instructions on installing foam Through the wizardry of Bob Wible, it's possible to insulate a 55-gallon tank with a single 4' X 8' sheet of foam board. You can find Bob's instructions here. Bob buys 1 3/8"Tuff-R poly insulation at Home Depot. It has foil on both sides. He also purchases (at Ace hardware) a 50-yard roll of 1.88" wide foil for each tank installation. Some set-up advice from our most senior salmonid raiser Trip Westcott raised salmon at the Lothrop School in Pittsfield, Vermont, for over a quarter century, making him (as far as I know) the most experienced TIC/SIC teacher in the state. After Trip retired in June 2015, he donated his very well-used equipment to our Vermont TIC program. (It's now back in use in Danielle Levine's classroom at The Schoolhouse Learning Center in Burlington.) Here are a few of Trip's set-up suggestions.
Current list of TIC schools and teachers
A few schools that decided late in the season to try to join the TIC program found that they would not be able to pull it off this year. Even so, we have 66 Vermont schools participating in the 2016-2017 TIC program. Thanks to a grant from the Jack and Dorothy Byrne Foundation, South Royalton School has two tanks, one high school tank and one in middle school, so that brings our tank total to 67. This is 30 more than we had last year! In addition, because many schools have two or more teachers collaborating on the TIC program, this year 93 Vermont teachers are doing TIC. You can find the latest list here. Observing, predicting, and controlling when it happens At the November 5 TIC workshop, we discussed two of the biggest challenges of raising brook trout:
"Swim-up" is a stage that occurs when alevin become fully developed. Prior to that point, alevin have been living on the bottom of the breeder basket, but when they approach being 100% developed, they start making tentative movements towards the surface. Experienced fisheries biologists like Roxbury hatchery's Jeremy Whalen can recognize the fairly subtle cues that indicate the alevin have reached the swim-up stage (when they'll be called fry). But TIC teachers and volunteers, who observe only a comparatively small number of alevin and who raise trout just once a year, usually find it very difficult to spot the telltale signs of the swim-up stage. As a result, we need to use data to predict when fry will swim up. And for this, we've created a data entry sheet and a special "swim-up calculator," which you can find here. Thanks to the efforts of Lorena Schwarz and with some help from Castleton University statistics professor Abbess Rajia, this new file is much improved over the one we demonstrated at the workshop. A quick note about the Excel file attached to the link above: it contains four worksheets. The first provides instructions, the second is used to PREDICT swim-up and to record water temperature data, the third will allow you to DETERMINE or CONTROL when the alevin swim up, and the fourth you won't need to use, it simply allows a formula to perform a "lookup" function. Below I've included a screenshot of the four tabs that give you access to the three worksheets you'll need to use. (For those who want to refine their ability to spot signs of the swim-up moment, check out this Idaho TIC document.) Predicting the swim-up stage Development is a function of water temperature and time. With each day that hatchery or tank water is at a particular temperature, a constant is added to the previous day's cumulative Development Index (DI). This chart (below) shows the relationship between temperature (in tenths of a degree) and the constant that is to be added to DI. So, for example, at 38.3 degrees, the value of 0.456 is added to whatever the cumulative DI was on the previous day. When a school gets its eggs in January, enter the date you receive your eggs into cell B4 in the "mm/dd" format, e.g., "01/12" would represent January 12 (image below). Either hatchery staff or your egg deliverer will be able to tell you how developed the eggs are on that day, that is, what their Cumulative DI is. This number is very important and should be entered into cell C5 of sheet B. From that point forward, all you need to do is enter the daily water temperature into the cell in Column B that corresponds to the correct date. The spreadsheet will automatically calculate the new Cumulative DI.
It is important to enter water temperature data for every day, including weekends and school breaks, even if you haven't checked the tank temperature. For those days when you don't visit the tank, estimate (or "interpolate") the water temperature. So if the temperature was 51 when you left on Friday afternoon and it was 49 when you returned to the classroom on Monday morning, enter a temperature of 50.5 for each of the weekend days. 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. And don't let the bottom of the net breeder get too dirty! (More on this later.) A week ago, on Saturday, November 5, 64 TIC teachers and volunteers gathered at Mount Abraham Union Middle-High School for the third annual TIC workshop. Based on comments offered and evaluations completed by participants, it was a valuable day of learning and sharing. (Click here to read evaluation comments.) Information was presented by Joe Mark, Jeremy Whalen, Bob Wible, and Doug Zehner, but many of the most important contributions were made by experienced TIC teachers in attendance. Bob Wible provided a helpful review of the AquaClear 110 filter and how to assemble it. He also explained how to modify the standard breeder basket so that it traps less debris. Group activities included water testing and using an Excel spreadsheet to estimate or even control when fry hit the critical swim-up stage. (Teachers and volunteers will be interested to know that, after the workshop, Poultney volunteer Lorena Schwarz proposed a simpler version of that spreadsheet--Yeah!--and then I took Lorena's version to Castleton University statistics professor Abbess Rajia, who simplified it further. Shortly, I'll be writing a special post about the new "Development Index Calculator" and giving all TIC fans access to it.) (Here's a page of six Release Day videos.) Two of the morning activities ran longer than expected, and this cut into time planned for visiting MAUMHS host Sam Kayhart's TIC tank, although Sam offered to take teachers to her classroom after the workshop. The second panel addressed ways to enhance TIC programs as well as a variety of approaches to Release Days. Other highlights included describing some of the "across the curriculum" ideas that various TIC teachers have developed in the past. Another TIC workshop in the books! Thanks to all who participated. Here are some links to the Vermont TIC Web site and to sub-collections within it:
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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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