TURTLE LAKE - Recent test netting of forage fish at Lake Brekken turned up a few small fish seldom seen in North Dakota - Iowa darters. Although they are known to be present in several waters in the state, they are few in number. A handful of Iowa darters were mixed in with thousands of fathead minnows captured in the nets at Lake Brekken last week.
Jason Lee, North Dakota Game and Fish Department biologist stationed at Riverdale, regularly conducts test netting at lakes within his assigned North Central District. Iowa darters are not new to him.
"We've got a few in here," said Lee shortly after emptying a net of forage fish at Lake Brekken. "We see them in a few of our district lakes. They are pretty common in the Missouri River system, not huge numbers of them, but we see a few. They are from the darter family so, obviously, they don't get very big."
This adult Iowa darter was recently discovered in a trap net at Lake Brekken in McLean County. They are a member of the perch family.
A 2-inch darter is about as big as they get. The colorful fish are seldom seen other than by biologists. The Iowa darter is unique among fishes in that it doesn't have a swim bladder. That means it can sink to the bottom of a lake or stream and easily stay there while searching for food such as copepods and midges and larvae found on underwater vegetation.
There are many species of darters, including an estimated 17 species of darters native to Iowa. Despite the name, Iowa darters are reasonably widespread in the United States, primarily in the range roughly bordered by Iowa, Colorado and North Dakota. Their numbers are believed to be declining to due increasing turbidity in many waters.
The darter gets its name from its incredible bursts of speed, said to be faster than what the human eye can follow. Although it is of ideal forage size, catching them is all but impossible for larger fish. Darters are simply too fast. Other minnow-sized fish require much less energy and effort to eat.