Grayling were once abundant in Michigan rivers and found nowhere else on earth. They were easy to catch, good eating, and beautiful, with a streamlined body, a huge dorsal fin, and colorful dots on fins and upper body. An early European settler recounts fishing for grayling. “It was no trick to catch them on a fly tied with the feathers of a blue jay or a squirrel tail,” he said. In 1865, specimens were sent to the Philadelphia Academy of Natural Science, where they were identified as a new species—Thymallus tricolor, the Michigan grayling.
When this news reached the little Au Sable River community of Crawford, the residents were so excited they changed the town's name to Grayling. By 1885, Michigan grayling were in trouble and by 1905, almost extinct. The last grayling was caught in the Otter River in the Upper Peninsula in 1936.
What happened?
• Logging. Michigan rivers quickly deteriorated when lumbermen began logging the nearby pine forests and floating the logs down to mill towns. They built dams, which blocked the grayling’s seasonal migrations, and
log slides on the riverbanks, which deposited silt on the grayling’s gravel spawning beds.
• Overfishing. Loggers caught large numbers of grayling to feed their crews. Thousands of tons were packed in ice, loaded onto railway cars, and shipped to Chicago and Detroit. In the 1880s, the railroad reached the Au
Sable River and brought sportsmen from all over the world to catch these beautiful fish that could be readily taken on artificial lures.
• Introduction of non-native trout. Originally grayling shared Michigan rivers with only native brook trout. In the 1870s and 1880s, the Michigan Fish Commission and private individuals stocked these rivers with non-native brown and rainbow trout. These non-native species competed with grayling for food, and since they spawn in the fall instead of in the spring like grayling, many newly hatched grayling ended up in the stomachs of six-month-old brown and rainbow trout.
For decades, biologists have been trying to figure out how to reintroduce the grayling in Michigan rivers. Between 1987 and 1991, the DNR stocked them in Michigan streams, but most of them disappeared within 6 months and the DNR gave up.
Why is it so tough to reintroduce grayling to Michigan rivers?
• Habitat. Grayling thrive in clear, ice-cold water loaded with bug life and they need the freedom to roam for miles during seasonal migrations. (That means no dams.) Thanks to long-term efforts to remove dams and improve water quality, Michigan rivers now are more welcoming to grayling, but still nowhere near what they once were.
• Competition from non-native species. Michigan rivers are filled with brown and rainbow trout, which compete with grayling for food and eat their fry.
• Imprinting. In the past, Michigan biologists reared grayling in hatcheries and transplanted them into rivers as young fish. As it turns out, that’s too late. Before they hatch, grayling eggs need to imprint on the chemical
makeup of the stream into which they are placed. If they are too old when transplanted, they won’t imprint on their birth stream and won’t return to it to spawn.
There’s a new group of biologists trying to reintroduce grayling into Michigan rivers. It’s called the Michigan Arctic Grayling Initiative—a collaboration between the Little River Band of Ottawa Indians, the Michigan DNR, and at least 40 other organizations. This group has collected grayling eggs from the Yukon River in Alaska and brought them to the Oden Fish Hatchery near Petoskey, where they were hatched, and then they transferred the newly hatched grayling to the Marquette State Fish Hatchery, where they will remain for 4 years until they are ready to begin producing eggs. To solve the issue of imprinting, the group has borrowed a technique from Montana, where biologists successfully introduced grayling by piping water into stream-side buckets containing
fertilized eggs. When the eggs hatch, grayling spill out of the bucket and into the stream, and they’re immediately imprinted. To solve issues of habitat and competition from non-native species, the group has given careful thought to where they want to plant the grayling and has decided on the remote upper stretches of the Manistee, Boardman, Jordan, Maple, and Au Sable Rivers. They expect to begin releasing grayling eggs into these rivers by 2025, and it will be five years after that before they can tell if their efforts are successful.