Not All Minnows Are Small & Small Fish Aren't All Minnows

Nov 21, 2018

Endangered Woundfin being raised in a U.S. Fish & Wildlife Service hatchery- a minnow species native to Utah's Virgin River.
Credit Niall Clancy

New genetic tools are making a big impact on fish and wildlife biology. A genetic study published earlier this year found that the group of fishes known as minnows actually consists of multiple different groups. This has led North American minnows to be reclassified as a new family of fishes called Leuciscidae. 

Professor Brandon Peoples, a minnow researcher from Clemson University, says there’s a difference between what scientists and the general public call ‘minnows.’

"People often use the term minnow just to describe any small fish. Oftentimes, just small individuals of our sportfishes are all called minnows. That’s kind of a common minnow misconception that we have. In reality, minnows are particular species of this newly dubbed family Leuciscidae," he said.

But not all minnows are small and the various species take on many different shapes and sizes.

"Minnows play a very diverse role in ecosystems and the roles that they play are as diverse as the species are themselves," said Peoples. "So some minnows are an important forage base for predators. But actually, other minnows are topminnows themselves. Other species of minnows are herbivores that control the entire food dynamic of stream ecosystems."

In Utah, there are both cold and warm-water species of minnows, many of which are listed as endangered or threatened by the U.S. Fish & Wildlife Service. 

Talking about the diversity of western minnows, Peoples says there are "several species you might be familiar with. We have the small minnows such as longnose dace and speckled dace, but you also have some pretty large growing minnows that make really long migrations. You have things like Humpback Chub, Hila Chub, the Utah Chub. Some can grow to be top apex predators like the Colorado Pikeminnow a species that is very impressive, very revered, but also very imperiled."

He also says that this sort of species reorganization, based on new genetic information, is far from a purely academic exercise.

"We often discover that what we once thought was one broadly distributed species turns out to be several narrowly distributed species. And, we may need to take a second look to assess species status, threats, and that kind of thing."

For more information on Dr. Peoples work, you can visit his lab website or check out his posts at The Fisheries Blog.