WATERBURY, Vt. (WCAX) – To some people, they’re only used to catch bigger fish, but biologists say minnows are a key part our our waterways.
Under Interstate 89 in Waterbury flows the Graves Brook. The babbling waters in an urban setting are filled with fish.
“When most people go to look for a stream, you know, especially in like, a more urban setting, when you look down generally what you’re looking at is a minnow,” said Will Eldridge, an aquatic habitat biologist with the Vermont Department of Fish and Wildlife.
Eldridge believes in the big impact of these small fish, with 24 different types of minnows just in Vermont, surviving in many different types of waterways.
“Most people, when they think about minnows, they just think small fish. But actually, minnows are their own type of fish,” Eldridge said.
Many anglers use minnows as bait fish, making them a key part of the natural ecosystem.
“They actually are part of that food web, and then other animals eat the minnows. So in the rivers, we have trout and larger fish, bass, panfish, things like that, that’ll eat minnows,” Eldridge explained.
They’re also a key resource for scientists because they’re a good indicator of water quality.
“Some species really cannot tolerate any silt or disturbance, things like that, and so we use them for that reason, as well,” Eldridge said. “What happens upstream is just as important as what happens here in this stretch of this stream.”
Eldridge’s fieldwork in the past helped dig up more information about these small creatures.
“I did a study a couple years ago where I marked a bunch of fish, I tattooed them, and I was able to identify individuals and I went back every couple months for a year to recapture to learn about behaviors,” he said.
Eldridge learned different species of minnows have different behaviors.
“That’s interesting because it means for the blacknose dace, what’s important for it is that local habitat having those pools and riffles and the wood and stuff like that habitat scale. But also what happens upstream, so the water quality coming to it. The longnose, dace the one that moves a lot, in theory it could seek out its preferred habitat. It can find areas that can meet its needs,” he said.
Despite their size, they can make it through some of the higher-flowing waters, surviving flooding like we’ve seen in the past two years.
“What they do is they will hunker down behind a rock or a log or something like that. So they’ll find kind of like what we call refuge from high flows, from floods,” he explained.
Eldridge says if you are interested, next time you’re near water, just look down!
“Minnows, in general, are less afraid of people than trout,” he said. “Trout are skittish; you have to sneak up on trout.”