The life span of an aquatic insect can be filled with many challenges. At any of its life stages (egg, larva, pupa or adult) it may fall victim to predators such as other aquatic insects, birds or salmon. Survival also includes making it through the freezing temperatures of winter and hopefully getting to emerge in the spring.
The Auke Bay Elementary School students spend outside science time at a local creek known as Bay Creek. This is where aquatic insects, salmon, birds and various other critters live. On these nature studies hikes, the students ask questions, observe and learn about the diverse life cycles in this aquatic ecosystem.
The aquatic insects and fish in Bay Creek will help the group learn about life cycles and how they can differ from one animal to another. Classroom drawings, field observations, and the “wow” moments in nature help create a relationship with place.
During a recent hike, I wondered if second graders understand death as part of the life cycle. I started asking questions about the life cycle of a salmon and talked about how salmon lay their eggs here in the fall.
Suddenly, the conversation switched gears.
The imprinted fall smell of Bay Creek had popped up in the noses of these young naturalists. The smell registered a memory and the students recalled one of the most amazing — although stinky — pieces of the salmon’s life cycle: death.
I’m certain the class will connect the salmon’s life cycle to that of the aquatic insects’ we are finding in Bay Creek.
I paused a moment to think about the structure of an invertebrate, such as a mayfly. I asked the students about the skeleton of an “invert.” Hands started going up and the word “exoskeleton” popped up.
“What other features characterize an insect?” I asked.
Mayflies have three segments head, thorax and abdomen and the students noticed gills on a mayfly’s abdomen. Another student remembered that insects have two antennae.
In the small dirty recycled yogurt containers the students were noticing aquatic insect locomotion. Can aquatic insect behavior help us learn more about our aquatic insect discoveries? In a recently released book “Aquatic Insects in Alaska” by John Hudson, Kathy Hocker and Bob Armstrong, it states that “swimming mayflies move their bodies up and down, whereas stoneflies move side-to-side”.
We could see this first-hand in our small buckets.
At some point, the mayfly will morph into an adult and, if a hungry swallow does not nab it up, it will live for a mere few days — just long enough to mate and lay eggs. It is so focused on reproducing that a stop at the local fast food joint is not in the cards.
Now, it is spring and I am eager to see some salmon fry.
But, with 10 stomping second graders we rarely find any salmon fry in Bay Creek.
This day we got lucky; the class naturalist, Miss BJ, literally stumbles upon a Dixie cup-sized size hole in the gravel, half full of water and half full of nearly a dozen one-inch-long pink salmon. These salmon were slithering around on top of one another, and their eyes seem as big as their bodies.
These are the “wow” moments that are so critical to education. This day, the salmon were our teachers. I found myself curious to hear what the students were experiencing.
At nature story time the air is filled with the smell of cottonwood and the class was noticing things as we passed around the mayfly, stonefly and caddisfly larvae in clear tubs. The tails, gills and the locomotion of these critters was observed as the group started to tell stories about our outside field trip and the life cycles of aquatic insects and salmon.
A question comes up.
“Do mayfly larvae eat dead salmon?”
“Well, I do not know … how about we leave that a mystery and look it up in a field guide.”
I am convinced these second graders ask questions like the experts.
Some of these aquatic insect larvae we collected will not make it to adulthood. Salmon fry, birds, other predacious aquatic insects and cold temperatures will challenge their survival.
When we draw, observe, and learn more about Bay Creek we add a real knowing to our relationship with this place.
As third graders these students will be back next year to discover more about this diverse ecosystem of Bay Creek.
• Kevin O’Malley is the lead naturalist with Discovery Southeast.