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Brown Trout: an Import from Other Countries, but an Important Fish to Anglers

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Brown Trout: an Import from Other Countries, but an Important Fish to Anglers Page 26 Wisconsin Trout Spring 2021 Wisconsin salmonids: Past, present and future Brown trout: An import from other countries, but an important fish to anglers. Words and photos by John Lyons arranged for a shipment of brown trout, in the form of fertilized eggs, Brown trout present an ultimate comprised of 20,000 bachforelle, challenge for trout anglers. An im- German for “brook trout,” a port from Europe, it is to many the stream-dwelling insect-eating form most desirable of the Wisconsin sal- of the Black Forest, and 60,000 see- monids, but to some an interloper forelle, “lake trout,” a larger fish- (“spotted carp”) which has re- eating form found in the lakes of the placed their beloved native brook Alps. These eggs were sent to feder- trout. Regardless of how you feel ally run hatcheries in New York about the brown trout, it has had a State and northern Michigan, where huge effect on the trout streams and they were hatched and raised for a fisheries of Wisconsin. It is the most year. The first official stocking in numerous and widespread trout in the U.S. took place in the Pere Mar- southern and central Wisconsin and quette River in Michigan, a Lake common in many areas of northern Michigan tributary, in 1884. Wisconsin. It is able to thrive in Soon brown trout stockings were streams where other salmonids of- being made throughout the country. ten cannot, and it persists and can Wisconsin received its first 1,000 grow to large size, even in the face brown trout eggs at the Bayfield of high fishing pressure. Hatchery on the shores of Lake Su- Brown trout are demonstrably perior, and the first stockings took NAMEKAGON RIVER, A CLASSIC NORTHWOODS BROWN TROUT STREAM the wariest and most difficult to place in 1887 in northern Wisconsin catch of all of Wisconsin’s stream streams. In 1884, eggs from brown trout, and their devotees spend trout from Loch Leven, Scotland, their entire lives differ genetically Brown trout also have more flex- countless hours and many dollars in arrived in the U.S., and they were from “lake-run” brown trout that ible spawning requirements. Brook pursuit. Occasionally, the fishing raised in Wisconsin hatcheries and spend much of their adults lives in trout need areas of strong ground- can seem almost impossible, but stocked in Wisconsin waters by the Lake Superior. Could this reflect water input, which disappeared as then on special rare days the fishing 1890’s. By the early 1900’s, all the the initial stocking of both the bach- the water table dropped from poor gods smile, and, if you have reason- major river systems and both Great forelle (resident?) and seeforelle land use and former spawning areas able skills, nearly every good cast is Lakes in Wisconsin had been (lake-run?) forms? The problem were covered with silt. Brown trout rewarded with a strike. Most outings stocked with some form of brown with this idea is that there appears like strong groundwater areas too, are of course somewhere between trout. to be little genetic difference be- but they aren’t as dependent on these extremes. But the appeal of tween bachforelle and seeforelle in them, and they could often spawn in brown trout is that each time you go their native Germany. But large ge- the gravel riffles that remained even Wisconsin brown trout netic differences may arise relatively after the groundwater areas were out, you can never be sure which strains kind of a day you’ll have. quickly when new populations are largely eliminated. The German and Scottish brown established from a small number of Brown trout were also harder to trout looked different, with the Ger- adults, which undoubtedly was the catch than brook trout and persisted The past: A new fish for man fish tending to have many red case with the first brown trout eggs in the face of fishing pressure that Wisconsin spots intermingled among black that reached Wisconsin. would have decimated brook trout The brown trout is native to spots of a range of sizes, and the It would be fascinating to use populations. The difficulty in catch- much of Europe, western Asia and a Scottish fish usually lacking red modern genetic methods to look at ing browns made them unpopular at small part of North Africa. It is a spots and having mainly relatively different Wisconsin populations and first. The techniques used for brook highly variable species in terms of large black spots. Anglers in the late try to derive their ancestry from the trout often didn’t work nearly as appearance, behavior, life history 1800’s and early 1900’s often distin- various European forms. A recent well on the more wary browns. and potential size. Some forms are guished between the two forms and study examined Lake Michigan and Some anglers complained that they adapted to spend their entire lives in identified the fish they caught as ei- Lake Superior browns in Michigan couldn’t catch the new arrivals and small streams, whereas some occupy ther “German browns” or “Loch and Wisconsin and found evidence lobbied for more stocking of brook lakes as adults and enter streams Leven browns” based on spotting of German and Scottish heritage trout and less of brown trout. But only for spawning, and some run to patterns. Even today, some anglers but also some indication of geno- other anglers embraced the chal- the sea like salmon. Most forms pri- speculate about which type they’ve types from Denmark and the lenge and developed new approach- marily eat insects and other inverte- caught. However, both the German French Pyrenees. This finding sug- es to catch the browns. As these new brates, and some lake dwellers focus and the Loch Leven fish were rou- gests that the origins of Midwestern approaches become well-known and on tiny zooplankton, whereas others tinely crossbred in hatcheries and browns are more complicated than widely available, the clamor against mainly eat fish. Each form looks a were mixed in the wild soon after we thought. brown trout subsided and eventually little different, and Europeans have they arrived in the United States, largely disappeared. given many of them their own color- and interbreeding appears to have Browns versus brookies Another reason for their accep- ful common names such as Ferox or eventually eliminated any “pure” tance was that brown trout grew Gillaroo. types in Wisconsin waters. It is fair to say the brown trout much larger than brookies in most The brown trout first arrived in What is interesting is that in Wis- saved Wisconsin trout fishing in the streams. Whereas a typical adult the United States in 1883. Fred consin Lake Superior tributaries early 1900’s. Browns were able to brook trout in an inland stream Mather, a well-known early fish cul- such as the Bois Brule River in survive and even thrive in streams might be only about 8-10 inches, an turist, had journeyed to Germany Douglas County and the Sioux Riv- where brook trout had been elimi- adult brown trout could easily be and become enamored of the brown er in Bayfield County, “resident” nated, and many parts of southern twice that. Many anglers were trout he encountered in Bavaria. He brown trout that remain in the river and central Wisconsin would have drawn to the possibility of a trophy had few trout if not for browns. This brown trout referred to in pounds was not because brown trout could rather than a brook trout referred tolerate more extreme warm tem- to in inches. Eventually, some an- perature or lower dissolved oxygen glers came to prefer brown trout to concentrations than native brook brook trout. trout as some fishery biologists and However, the dislike of brown anglers have assumed. Both labora- trout among other anglers never tory and field studies demonstrate completely faded out, in large part that temperature and oxygen toler- because in many instances brown ances are similar for both species, trout displaced brook trout. The although brown trout do prefer and reasons for this aren’t completely grow better at slightly warmer tem- clear. Some experimental studies peratures than brook trout. show that brown trout are more ag- What the brown seems to have gressive and able to chase brook been able to do was handle habitat trout away from the best feeding degradation better, particularly sed- and resting areas. But other studies imentation. Widespread poor agri- show that among fish of the same cultural and timber harvest size there is little difference in com- practices in the late 1800’s and early petitive abilities between the species 1900’s had led to massive erosion or even that brook trout may some- that choked streams with sand and times be able to outcompete brown silt. Brown trout were not immune trout. to these impacts, but they were bet- I speculate that the dominance ter able to deal with them than of brown trout in many Wisconsin brookies. As stream pools filled and streams may lie in their faster rocky substrates were covered by growth rates and larger ultimate VARIATIONS IN LAKE-RUN BOIS BRULE BROWN TROUT sediments, brook trout disappeared Two lake-run browns from the lower Bois Brule River during their spawning size compared to the brook trout. but brown trout often could hang At water temperatures from the 60’s run, showing some of the variation in coloration and spotting patterns. on. to the low 70’s, which is typical of Spring 2021 Wisconsin Trout Page 27 many Wisconsin trout streams in Great Lakes states, began stocking summer, brown trout grow faster coho and Chinook salmon, steel- and reach a larger size than brook head (rainbow trout), and once trout.
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