First, the bad news. My bad. My very bad!
Concerned that the very fine mesh netting of the breeder baskets we buy from ThatPetPlace.com was a major cause of high alevin mortality in March, I spoke with Dale Spring of Poultney High School. She offered to have her students sew 24 replacement bags out of coarser netting that I purchased from a local sewing supply store.
The students did a great job, and, as an experiment, I gave each of a dozen southwest Vermont TIC schools two bags each. The recommendation was that they use both the supposedly "improved" bags made of coarse netting but also still use the commercially provided bags made of finer netting. I asked teachers to record losses separately for the two types of bags. Great idea, huh?
Except for the law of unintended consequences!
Everything seemed to be going well until yesterday when Castleton Village School's Gay Merolle reported that alevin were able to poke their skinny heads through the coarse netting. Not good! I suggested that Guy and other southwest Vermont teachers abandon the coarse netting bags at this point.
Then this morning Rutland High School's Dawn Adams e-mailed me to say that over the weekend, 75 alevin escaped and were in the gravel, that is, if they hadn't gotten sucked up into the filter! Note to self: remind teachers to install fine mesh over the filter intake fittings!
Now some good news.
First, most schools seems to be doing extremely well. Except for those who are keeping the tank temperature in the low 40s, just about every school has seen all of its eggs hatch. As first-time TIC teachers have observed, alevin don't do much. They just hang out on the bottom of the netting at this point in their development (which is why they're so likely to become infected if the bottom of the netting isn't cleaned regularly once you're adding food). If you're afraid they might be dead, you can jiggle the breeder basket a bit. Almost certainly they're alive.
And second, tonight, the inaugural edition of Vermont PBS's Outdoor Journal will include a segment on Trout in the Classroom, specifically focussed on last May's Release Day at Mary Hogan School. I've put a link to that show on our new "TIC in the media" page. (Let me know if you're aware of other Vermont TIC media coverage that's posted on the Internet.)
Unless otherwise noted, all these reports came in on Thursday, January 21, 2016.
Mollie Sprague, Lincoln Community School teacher, worried whether her tank's 14 preemies suggested a problem.
Bob Wible and I assured her that it didn't; in fact, Bob mentioned that at least one of the central Vermont tanks had 19 or more preemies.
Sam Kayhart, of Mount Abraham UHS, said: Our trout seem to be on track. I calculated the DI as 53.4, and 75% of the eggs have hatched. My students will begin tracking water chemistry tomorrow. Lots of excitement in Bristol!
She also provided the photos below.
Keith Harrington (Poultney Elementary School) said, Our eggs are hatching like crazy! Just now a couple of students and I watched about a half dozen hatch. I don't think worrying about them hatching over winter break will be a problem. At this rate they will all be hatched very soon. It is nice however that they are all doing so well. We have had a very low mortality rate with the eggs themselves.
On that same day, Castleton Village School's Guy Merolle reported, "[Eggs} are definitely strong-eyed now. Check out this graph from my website:"
Here's a link to Guy's full site, complete with other graphs.
Jason Gragen, of NewBrook School, reported: "Water numbers look good. Tank is running at 46 degrees. Two questionable eggs were noticed after pick-up at hatchery; they didn't make it, as expected. Six eggs have hatched; three have made it; three haven't. That puts our total loss at five to date. The kids are having a blast as usual, and completing some nice work in their journals!"
And today, Friday, January 22, Deb Scott told us about her two-headed alevin (photo below). In fact, when I look at that right-hand "neck," I almost think I see a third set of eyes. What do you think?
Now that schools have their eggs and eggs are starting to hatch, some teachers have begun to ask, "When do we feed them?"
This may be the most important question faced by those raising brook trout. Our newly hatched little critters are called "alevin," pronounced al-a-vin, with accent on the first syllable, which sounds like "pal." Like tadpoles, alevin sit atop a yolk sac. This contains all the food they'll need for several weeks. How quickly they consume that food depends on water temperature. At 52 degrees, it could be gone in a month or so; at 40 or less, the yolk sac might last three months.
Because none of us have much experience raising trout, we don't develop the ability to see the subtle changes that permit hatchery personnel to recognize when the alevin are approaching the "swim-up" phase, when they will start looking for food on the surface.
As a result, it's critical that TIC schools keep good daily temperature records and use these to calculate Cumulative Development Index. This process is so important that we have a special Web page to explain the methodology. That page (link below) also includes a form that will allow you to determine what your water temperature should be in order to bring alevin to the swim-up phase just when you want them to get there.
A number of teachers have reported that some of their eggs have already hatched. This morning Bob Wible sent me these pictures.
I'll ask Jeremy Whalen to give us his opinion, but I assume that, even under ideal conditions, a certain percentage of premature births is normal. Think about it, what percentage of 200 human births might result in premature delivery?
In addition, if some of our egg batches got overdosed with iodine, that could very well cause a higher rate of "preemies."
And the eggs in the top picture above appear otherwise healthy. So I wouldn't worry if a small number of eggs hatch this early. But I wouldn't necessarily expect alevin hatching this soon to survive. Those of you who experience early hatching will have to tell us how those preemies do.
P.S.: After I wrote the above post this morning, Jeremy responded via e-mail with the following:
I believe DI-wise they should be over 40 now at 47 degrees or so. Keep in mind the 58% DI is 90% hatch if you look back on the sheet, so it's possible for hatch to slowly start happening. The picture of the one fry I did open looked good and healthy to me.
Most of us, and that includes me, don't have a lot of experience working with brook trout eggs. So I get a lot of questions, especially from new TIC teachers, about whether their eggs are normal-looking or not.
This morning, for example, Lisa Marks, of Ludlow Elementary School, asked for my opinion about her eggs. I suggested that she send me a couple of photos. See the two photos below.
I thought they looked good, but I decided to check an expert, so I e-mailed the photos to Jeremy Whalen. He got back to me very quickly to say that they looked good to him as well.
Then early this afternoon, I got a photo from Jim Mirenda, at the Dorset School. Here's what Jim sent.
Although Dorset's eggs may have more color--it might just be the amount of light under which they were photographed--their eggs look good to me too.
No sooner had I written my chirpy post on Friday about a day spent picking up and delivering eggs for 11 southwest Vermont schools, when some distressing stories began to roll in.
Green Mountain Valley School's Meg Lyons was the first to report extremely high die-off rates within the first 24 hours of receiving her eggs. Williston Central School's Colleen O'Brien wasn't far behind. But some teachers--Mary Hogan's Steve Flint and Bethel's Deb Scott among them--seemed to be having perfectly normal die-off rates.
Even schools that I delivered to within minutes of each other reported very different levels of mortality. For example, Dorset School, where I delivered eggs at 2:00 p.m. on Friday, had very few bad eggs; while MEMS, who get their eggs 15 minutes later, lost just about all. Both experienced and new TIC teachers were having problems, but some new and experienced teachers were also having good results. As the king says in the King and I, this was "a puzzlement!"
Dorset School volunteer Jim Mirenda offered the first hypothesis about what might be going wrong. On seeing some photos I took of dead and dying eggs, Jim observed that it appeared that a chemical had partially dissolved the shells of the eggs.
Other problems included the fact that some eggs hatched prematurely (see above), perhaps due to the partially dissolved shells. In addition, many teachers observed eggs clumped together (evident in this next photo). Maybe these eggs were stuck to each other because their shells had become a sticky, gelatinous substance.
This morning, Jeremy Whalen, supervisor of the Roxbury Fish Culture Station, said that he believes that some of the batches of eggs were exposed too long to the iodine solution treatment that the hatchery uses to reduce the risk of infection. Since the length of exposure varied by batch and day, this would explain why some schools had terrible losses while others had hardly any.
So what do we do? If you haven't lost a lot of eggs, consider yourself lucky and carry on! Schools that lost or are losing a high percentage of their eggs should discard the eggs and thoroughly clean net breeder baskets. Then, either directly or through a local TIC liaison, they should arrange to get new eggs from Roxbury. Jeremy has assured me that any iodine introduced to the aquarium by the first batch of eggs should not be a problem. I assume that the very small amount of iodine that was in your egg container would be so diluted by all the water in the tank as to be incapable of harming the new eggs.
In a way, it's good that these problems arose so early when Jeremy still has plenty of eggs to resupply those tanks that suffered great losses.
I know this won't be our only TIC crisis this season, but let's hope it's the last one that affects so many schools across the state.
Friday, January 8, proved to be a delightful day for the almost two-hour trip from Castleton to Roxbury. On the road before 8:00, twenty minutes later I'd picked up my 12-year-old grandson Calvin and Joe Kraus, membership chair of Southwestern Vermont Trout Unlimited, and we were headed north. By 10:00, we pulled into the parking lot of the quaint and historic Roxbury Fish Culture Station, founded in 1891, the second oldest hatchery in the country.
Two weeks earlier, I'd mailed a box of storage containers to Jeremy Whalen, hatchery supervisor, and he was ready for us when we arrived. After collecting food for each school and packing 11 red-topped plastic squares into a cooler I'd brought--carefully insulating them from freezer packs in the bottom and surrounding them with family towels to ensure they didn't slide around--we loaded our precious cargo into my 4Runner.
An hour and a half later we visited Rutland High School to deliver 200 eggs to Dawn Adams. Next stop was the Holiday Inn parking lot, where Joe left us and we rendezvoused with Kathy Ehlers, another Southwestern Vermont TU board member. Kathy's mission was to take eggs to Ed Robbins, at Mill River Union High School, and Lisa Marks, at Ludlow Elementary. Once we said good-bye to Kathy, Calvin and I were off to Castleton Village School, where Guy Merolle and his students were waiting for us.
From Castleton, after picking up three slices of pizza--two for Calvin, one for me--it was on to Fair Haven Grade School. One of Chris Stanton's students led us to her classroom so we could deliver eggs both for Chris as well as for Benson Village School. (BVS's Archie Clark would come down to FHGS at 3:15 to collect his babies.) Then we headed south for the big drop-off in Poultney.
With 9/11ths of our deliveries accomplished, we were off to Bennington County.
Forty minutes later, we arrived at Calvin's school, the Dorset School, and made our way to Karli Love's 5th grade classroom. Karli was out with a sick child, but volunteer Jim Mirenda was already setting up equipment so students could examine their new eggs.
This will be a busy time for most VT TIC schools. Some schools are just finishing setting up their tanks. Others are trying to purchase a few remaining supplies. Don't forget that, on Chuck Dinkel's advice, we're recommending that everybody double the use of MicrobeLift Special Blend and Nite-Out II.
And of course, most important is treating your water with NovAqua Plus before your eggs arrive.
Speaking of eggs, with help from Joe Kraus, Kathy Ehlers, Meriel Brooks (more about her later), and Jim Mirenda, this Friday I'll be picking up eggs and food at the Roxbury Fish Culture Station for 11 of southwest Vermont's 13 TIC schools.
I'll hope to provide a report on that outing in a few days.
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.