Wade a Little Deeper, Dear
Another Tuesday morning, and the Nature Group was back at Brown’s Lake for more fishy adventures.
Today we were going to go seining, which means taking a very long net through the water to see what fish we could capture in its folds. Unfortunately, the seining nets we have at Dahlem are the wrong kind – they are stiff netting, more like window screening, and designed more for catching invertebrates than fish. So, we just took our large dip nets into the water and tried our luck at catching fish with them instead.
Our route took us down a narrow channel between Brown’s Lake and Williams Lake, with many thanks to friends who live right at the start of the channel and hosted our visit.
Later on, however, someone had some luck and caught one of the fish. We thought they might be young blue gill sunfish, but it turns out they are actually Norther Longear Sunfish, which are native and small. The breeding male, which we believe these were, are only about three inches long!
There were lots and lots of young water striders out and about.
Here is another fish someone caught:
My favorite find of the day, though, were these looped tubes that were billowing in the current. They were anchored to logs and rocks…but what in the world were/are they?
It took a little digging and some creative word searches online, but I’ve finally discovered what they are: they are the homes and food-catching nets of Neureclipsis, the trumpetnet or tubecase caddisfly! I’ve seen lots of caddisfly larvae in my life, with a variety of cases made from sticks, tiny stones, soft plant material…but this is a first for me. These larvae spin their tubes out of silk directly into the current of the stream/river/outlet/inlet where they live. The tough yet delicate fibers collect silt and other debris which give them a rather underwater cob-webby appearance. The ends are open, and the water flows through. Bits of plankton and such are caught inside, and the larvae, which is a fierce predator, will also come out to snag anything that disturbs its net, thinking it might be something good to eat.
Another mystery solved.
Bill brought us a clump of this underwater plant, which feels very rough and strange. Apparently, it removes calcium carbonate from the water, adhering it to its leaves and stems. It is called chara, or muskgrass or stonewort, and it is in fact an algae (alga, singular). Chara grows in rich limestone areas, where the water is poorly oxygenated and hard. Apparently, if you have mosquito larvae, you won’t have this plant. So, Bill (our host, not the one with the plant here) – no mosquitoes at your house! According to Bill (holding the plant), it won’t burn when dried, and if you pick it up after drying, it just crumbles away to dust.
Gary found the rare freshwater yellow sole:
And we had this young crayfish. None of us are crayfish experts, but we have a poster on the door of our office that shows the different species of Michigan crayfish, including invasive species. We think this might be the Northern Clearwater Crayfish, which is native. Can anyone tell us differently?
This was the third fish we caught. Another little minnow of some kind. We will be consulting with our fish expert to see if we can get an ID. Minnows can be devilishly tricky to identify: you often have to resort to counting scales. This might just be the fishy equivalent of an LBJ (term used to ID sparrows of unknown ancestry: little brown jobbers).
All in all, it was a great morning, despite the overcast and slightly chilly conditions. Many thanks to Bill and Linda for hosting our group two weeks in a row!
Want to join us on a Tuesday morning adventure? Next week we are meeting at the Ecology Farm at 9:05 AM and will be investigating what is blooming at the Wickwire Field (which we planted to native grasses and forbs last year).