Dean Hansen—OBTU’s “Bug Keeper”—Helps Chapter Complete 10th Year of “Trout in the Classroom”

By Jim Schmiedeskamp

Oak Brook Chapter TU has successfully completed its 10th year of supporting “Trout in the Classroom” (TIC).  TIC is a program that allows participating schools to raise trout from eggs to juvenile trout in a class from aquarium tank and release them in a northern Illinois trout stream or Lake Michigan.  This year OBTU supported 11 school programs.  Students from these schools released their trout during the week of April 30.

These release field trips are the culmination of a year’s activity for these students, as they visit the trout stream, test the water quality for comparison to their school tank, and seine and survey for aquatic nymphs and organisms that are part of the trout’s ecosystem.  And of course, they release their trout fingerlings.

This program could not have been successfully completed without the support of OBTU volunteers.  In fact, this year between the April entomology presentations at TIC schools and the release week, 28 OBTU volunteers worked a total of 73 volunteer days.

Dean Hansen is Oak Brook TU’s “bug keeper” providing an array of live aquatic insect specimens for a week’s worth of classes supporting the chapter’s “Trout in the Classroom” program.  The Oak Brook TU program looks forward to Dean’s annual migration from his home in Minneapolis to Chicago every spring for his interactive entomology presentations featuring mayflies, caddisflies, damsel flies and hellgrammites.  Now 75 and a retired commercial bee keeper,  Dean continues to pursue his life’s passion studying insects now with the underwater variety as a volunteer educator.  Here’s a recent interview with Dean as he marks his eighth year as the chapter’s featured entomology classroom expert and presenter.

OBTU’s 2017-18 Trout in the Classroom school year was Dean Hansen’s 8th with the chapter.













What do you call your home town?
I grew up in south Minneapolis, just a couple houses from Minnehaha Park, with lots of trees and grasses, and, of course, Minnehaha Creek. OK, not a Class I trout stream, but, still, moving water.

Did you fish as a kid? If yes, for what and with what kind of tackle?
Our parents took a family vacation every summer, usually to a resort on a lake in northern Minnesota. Fishing started at age five or so, with a casting rod and a worm on a hook.  The neighborhood kids also did some worm fishing from the shore of nearby Lake Nokomis.

What was your major at the University of Minnesota (UMN)? I know your graduate work was in entomology. What was your PhD focused on?
I started in the Institute of Technology, first year as an aeronautical engineer, second year as a physics major, but then I did a major switch and became a zoology major for my junior and senior years at UMN.
Funny how life can hinge on such minor points:  Near the end of my junior year, I was walking down the stairway in the Zoology Building and saw a notice about field classes at the UMN’s Itasca Biology Station.  I got the very last available spot in “Field Entomology.”  That six-week session at Itasca changed my life.  I finished my senior year as a zoology major and then entered graduate school as an entomology major in the fall of 1964.  I was fortunate to be able to work on an interesting group of small flies, the larvae of which, in Minnesota and Wisconsin, live in cold trout streams.  In the mountains in the West they are found in similar streams and can be the major group of insects found in such demanding habitats as snowfield and glacier meltwater streams.  They are also found in moving waters above timberline in the Arctic.  I spent parts of three summers collecting specimens in the Big Horn Mountains, on the Beartooth Plateau in Wyoming, and in the Cascade Mountains in Washington.  I worked on nailing down the morphology of the adult stage and then describing the 30 species I found, 10 of which had not been known to science before.

Did you spend your entire career as a commercial “beekeeper”? How did you pick this profession and what did it entail?
Academia was in a contracting phase when I got out in 1973, and, even with a year of college teaching experience (at the UMN Duluth, 1970-71) behind me, I wasn’t able to find a job. I had started keeping a hive or two of bees in 1966, and when the price of honey went from 13 cents in 1970 to over 50 cents in 1973.  I saw commercial beekeepers doing very well financially, so I decided to go where I could earn a living.  I worked for a commercial beekeeper at his family’s honey packing business in 1973-75, while I built up my own beekeeping operation.  My business eventually grew to about 640 colonies of bees, in Minnesota and nearby spots in neighboring Wisconsin.  I sold my honey in 55-gallon barrels to a few specialty bakeries.  I figure I sold something over 1.3 million pounds of honey over the years.

I believe you mentioned you are still working part-time for a local engineering consulting firm responsible for conducting environmental impact assessments for discharge permits for mining activities in northern Minnesota. Do you physically collect the specimens for these studies as well as for your “Trout in the Classroom” programs? If yes, from how many different streams?
I mainly look at samples that have been collected by others, either from northern Minnesota for the possible mining ventures, but also for some watershed districts, and for an agricultural products plant.

I do collect all the live aquatic insect larvae I use in the TIC programs.  I’ve been doing this for five decades, and I joke (but it’s the truth) that I know the square meter to go to in order to collect Hex nymphs, clinging mayflies, giant stoneflies, etc. The Hex nymphs come from one spot, the hellgrammites from a different river, the caddis larvae and clinging mayflies from a third, on and on.  I’ll go to four or five streams to get the material I need for the TIC programs.

How important is TU’s stream restoration work to maintaining a healthy aquatic insect population?
Several factors will work to reduce a healthy population of aquatic insects. Water temperature, of course—this can get complicated, and I’m not in favor of planting trees along a stream to provide shade.  A major detriment in a stream is excessive sediment input.  Tom Waters authored an entire book, “Sediment in Streams”, on just this subject.  Another detriment is lack of “LWD”—that is, Large Woody Debris.  Most insect larvae need something solid to hang on to, be it a rock, submerged tree trunk or branches, or underwater rooted plants.  Shifting sand is all but a biological desert as far as an insect larva is concerned.  Any restoration work that seeks to maintain cool spring water input, reduce fine or coarse sediment, and prevent agriculture chemicals from being washed into a stream, and enhancing the amount of natural “debris” in a stream will be beneficial.  I’ve seen an old car tire being removed from a stream.  It was covered with caddisfly cases, black fly larvae, and some Baetis mayfly nymphs.  That old car tire was providing good solid habitat for a variety of aquatic insects.  But did it belong in the stream?  Absolutely not.  But try to replace it was some rocks or woody debris.  Except for the mud-loving Hex, some sprawling dragonfly nymphs, and bloodworm larvae, the majority of aquatic insects need something solid—even it’s just a submerged leaf blade of a streambank grass—to hold on to.

If there was one aquatic insect that was the proverbial “canary in a coal mine” for detecting water quality issues in a coldwater stream, which bug would it be?
That’s a hard question to answer. I can get to the base of a snowfield and find only one or two chironomid (“my” group of aquatic insects) larvae in the pure, cold stream flowing from under the snowfield.  They’re the only species adapted to living there.  I’d say there’s no “one” proverbial canary in the coal mine.  What one wants is a diverse array of species, some grazing the algae on the rocks, some collecting tiny chunks of food from the water, some shredding the leaf fall and woody debris that get into the stream.  One wants a community, not just a single “good” species.

How many years have you been supporting the Oak Brook TU “Trout in the Classroom” program?
Eight years, is it?

Q. How many different species of live “bugs” do you collect for our TIC classes?
I need to go to five or six streams to get the variety of insects needed. I’ll try to collect about 100 total across these groups: stoneflies, burrowing mayflies, mayfly clingers and swimmers, caddisflies and hellgrammites.

How interested are today’s middle and high school students in your “hands on” content?
I’d say “very.” Actually, the hands-on part of my classes is particularly effective with special education students with some sort of learning challenge. I’ve had several special ed teachers tell me that this is “just perfect” for these students. They use their eyes, their hands, they don’t have to memorize something that will be on a test. They are sort of set free to look, observe, question, hesitate, work at their own pace.  I don’t do that many high school classes—nearly all elementary and middle schools students.  The younger, the better, I feel.  I’ve watched six-year-olds jumping up and down, shaking their arms, and shouting with excitement.  You’ll never get a cool high school senior to do that.

Do you fly fish for trout today?
Yes, but not as often as I’d like.

If yes, do you tie your own flies?
I have in the past. Maybe again this year.  Or maybe I’ll be content to collect chironomids in a snowfield meltwater stream on Wyoming’s Beartooth Plateau again this summer.