Apple River

Description

There are approximately 1,632 miles of rivers and streams in this area. The headwaters of the Apple, Galena, Sinsinawa, and Menominee Rivers are in Wisconsin, and all of these streams flow south by south-west into the Mississippi River. The channel slopes are relatively steep, averaging from 13 to 20 feet per mile.  The smaller tributaries are often steeper, often exceeding 40 feet per mile!  The steep channel slopes and hilly topography result in excessive erosion in many areas, exacerbated by livestock grazing on the slopes, and by poor farming practices.  Seven stream segments in this area are recognized as Biologically Significant Streams because they support threatened or endangered species or have high fish and mussel diversity.  These segments, which cover more than 22 stream miles, include the Apple River from Wolf Creek southeast to Mill Creek, West Fork Apple River, Plum River from East Plum River to Carroll Creek, Carroll Creek, Menominee River, Sinsinawa River, and river miles 545-550 of the Mississippi River.

Fishery History

The most common collected sport fish in the Upper Mississippi River Basin Survey in 2021 was the smallmouth bass.  A total of 1,248 smallmouth bass were collected over the 19 sites.  Naturally reproducing populations were found in all of the stream sites with recruitment maintaining stable smallmouth bass levels. The size structure of the smallmouth bass from the 6 Apple River stations was also good with 23% over 14 inches in length, and 2% over 17 inches in length.  The 2 South Fork of the Apple River sites had 23% over 14 inches. The size structure of the smallmouth bass from the 2 Plum River sites was also good with 23% over 14 inches in length, and 3% over 17 inches in length.  The 2 Carroll Creek sites had 14% over 14 inches.  East Fork of the Galena had 16% over 14 inches.  The 2 Galena River sites had 5% over 14 inches.  The Menominee River site had 20% over 14 inches.  The Rush Creek site had 33% over 14 inches.  The Sinsinawa site had 33% over 14 inches.

 Bluegill was the second most common collected sport fish, found at 14 stations, for a total of 315 fish collected. 

Channel Catfish were locally common outside of the upper Apple River with a total collection of 69 fish from 5 of the stations.

Walleye and sauger were also only locally common in the stream stations closer to the Mississippi River with 23 walleye collected from 6 of the stations.

Additional Information

A total of 19 locations were sampled within the Upper Mississippi River Basin during the summer of 2021 (Table 1).  Six samples were collected from the main stem of the Apple River, along with two samples from tributary of the South Fork of the Apple River. Two samples were collected from the Plum River main stem, along with two samples from Carroll Creek, a tributary of the Plum River. Two samples were collected from the Galena River, one from the East Fork Galena River, and one sample was collected from each of the following: Menominee River, Sinsinnawa River, Rush Creek, and Smallpox Creek.  All sites were sampled using a small DC electro-fishing boat equipped with a 5.0 GPP Smith Root box and generator.  One person was usually netting stunned fish from the front of the boat, while additional people collected stunned fish by walking alongside the boat in the water as depths permitted. Most of the larger fish were enumerated in the field with lengths (total length) recorded to the nearest mm, and weights measured to the nearest gram. Smaller fish, primarily minnows, were preserved for later identification.  These fish were then similarly enumerated.

A total of 58 native fish species and 3 non-native fish species were collected from the 19 sites.  The most numerous species collected during the 2021 basin survey was the white sucker, followed by the smallmouth bass, common shiner and bluntnose minnow.  The most commonly occurring species were the smallmouth bass and the white sucker which were both collected at all of the stations sampled.  

 The Upper Mississippi Basin can be divided into 2 distinct groups of streams; 1 group contains all of those streams that are a part of the Apple River Basin, and the 2^nd group contains those streams that are outside the Apple River Basin.  These two groups are very different in the diversity of species that they harbor. This distinction occurs because the Apple River is closed to fish migration due to the presence of a large dam at Hanover which was first built in 1829. The dam is close to the mouth of the river, being located only about 10 miles from the confluence with the Mississippi River. This dam effectively blocks fish migration for a variety of species that occur in other streams in the basin.  In 2021 one sample was collected immediately downstream of the Hanover Dam.  This sample contained 14 species that were not collected anywhere above the dam, and many that have not been collected above the dam since collections started in 1995.  

The Upper Mississippi River Basin consists of high gradient, rocky bottom streams supporting unique fish assemblages.  The Largescale Stoneroller and the State Threatened Ozark Minnow are found commonly in these streams but are rare or non-existent elsewhere in Illinois.  The Longnose Dace has been found in several locations in the Driftless area streams, but elsewhere in Illinois it has only been found along the shallow shores of Lake Michigan.  Brook Sticklebacks were found in a few locations but are sporadic throughout Illinois due to their unique habitat requirements, and the largest populations of Black Redhorse are found in this area of Illinois. Most of the stations sampled had cool water with a high oxygen content and good flow, and only a few stations in the lower reaches were moving sluggish and showing muddy sediments.  These Upper Mississippi River tributary streams should be protected due to the unique fish assemblages they harbor.  The Driftless areas streams are also notable for the high quality of the Smallmouth Bass fishery.  People travel from all over to take advantage of the excellent fishing available at Apple River Canyon State Park.    Protection of the water quality of this area should be a priority when making any decisions for development in the region.