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Fish Reports

2007 Report

Pool 8, Upper Mississippi River 2007 Fish Collection Summary

This report is a bullet summary of the Long Term Resource Monitoring Program's (LTRMP) fish collection efforts conducted by the Onalaska Field Station for Pool 8 of the Upper Mississippi River in 2007.

• 179 fish collections were conducted using six gear types. Of the 179 collections, 160 were from randomly selected sites. Nineteen collections were made at fixed TWZ sites (Table 2.2).
  
  
• Water levels did not affect sampling allocations, but a quick rise in water levels in early October caused the loss of one large hoop net in the tailwater zone. The 2007 hydrograph was characterized by an early April rise, then below normal water levels through most of the spring and summer.  Record rainfall over a 24-hour period in late August caused a quick spike in water levels, and more rainfall in late September caused October water levels to be much higher than normal (Figure 1.2).

• Backwater, main channel border-unstructured, and side channel border strata strata received the most sampling effort (Table 2.2).
  
  
• 23,351 fish were collected representing 58 species and 2 hybrids (Table 3). This total includes 635 unidentified sunfishes (Centrarchidae), 4 unidentified suckers (Catostomidae), and 1 unidentified minnow (Cyprinidae) less than 30 mm long (Table 3.2).
  
  
• Historical fish distribution records for the Upper Mississippi River (Pitlo et al. 1995) document 99 fish species from Pool 8.
  
  
• The LTRMP species total for Pool 8 before the 2007 season was 90; no new species were added to this total since 1997.
  
  
• Several species were collected that are listed on Wisconsin’s rare fish list, including the following:  1 mud darter, 2 western sand darters, 479 weed shiners and 69 pugnose minnows (special concern), and 19 river redhorse (threatened) (Table 3.2).
  
  
• Mean catch-per-unit-effort and standard error for fish collected using stratified random and fixed-site sampling for each stratum are shown in Pool 8 tables. Length distributions for selected species of fish are shown in Figures 1 to 17.