Michigan Brook Trout Facts

Brook Trout | Credit: USFWS

The brook trout is Michigan's official state fish. This colorful member of the char family is native to the Great Lakes region. 

Brook trout have a large mouth and streamlined body shape that is typical of trout and char. They can display an array of colors, including olive, bluish gray, slate, or black above with a silverish white belly and wormlike markings (vermiculation pattern) along the back. Along their flanks are yellow blotches and red spots, which are sometimes surrounded by light blue halos.

Brook trout are found in cold water streams, around rocks, logs, and undercut banks. They are also found in the Great Lakes and smaller lakes throughout Michigan.

They prey mainly on mayflies, stoneflies, and other aquatic insects. Brook trout are opportunistic feeders and will feed on available food sources including, crustaceans, worms, and small fish.

Brook trout mature in about 1.5 to 2.5 years to mature, and they usually do not live longer than 6 years. Stream-dwelling brook trout typically reach 7 to 9 inches in length.

In offshore waters of the Great Lakes, coaster brook trout sometimes reaches 25 inches in length and weigh 10 pounds or more.

On the Lower Peninsula, the Black River system is considered to be one of  the best brook trout streams in Michigan.

Brook trout are common throughout the Upper Peninsula, especially in streams that contain clear, cold  water. In summer, brook trout often migrate to the headwaters of tributaries in search of colder water.

What is KHV?

Koi herpesvirus (KHV) is a disease that affects fish such as common carp, goldfish and koi. The impact of KHV on native minnow species of North America is not fully known.

KHV disease is found worldwide and likely was introduced in North America from the release or escape of infected ornamental fish.

KHV is suspected to be the cause of a June 2011 fish kill which involved an estimated 300 to 500 common carp in Michigan.

"This virus is capable of large-scale common carp die-offs as seen in Ontario in 2007 and 2008," said Gary Whelan, DNR Fish Production Manager. "The virus is an internationally reportable disease, and it is being officially reported at this time."

source: Michigan Department of Natural Resources

Michigan Fish Kills Due To Cold Winter

Gizzard Shad

A fish kill involving gizzard shad which occurred in southeast Michigan is a natural event due to harsh winter weather conditions and a large year-class, according to the state's Department of Natural Resources and Environment.

The department received reports of fish die-offs in southern Michigan beginning shortly after the New Year. The reports are coming from the St. Clair River, Lake St. Clair, the Detroit River, and Lake Erie.

Gizzard shad are native to the Great Lakes with the exception of Lake Superior. Shad can be seen concentrated at warm water discharges of industrial plants.

Gizzard shad are an important forage fish, providing a high-energy food resource for predator species such as walleye, muskellunge, smallmouth bass, and northern pike. Like many forage fish species, annual abundance of gizzard shad can vary drastically between years.

Shad are filter feeders, feeding on both zooplankton and phytoplankton, and can reach a size of 19 inches. However, most of the gizzard shad involved in the fish die-offs are five to six inches long.

There was a very large hatch of shad in the spring of 2011 throughout the St. Clair system, resulting in large schools of these young shad.

Anglers along Lake St. Clair have reported seeing large schools of gizzard shad passing through their ice holes while perch fishing. According to the department, more shad die-offs were expected through the winter and into spring.
 
source: Michigan Department of Natural Resources and Environment