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Fish Reports

2004 Report

Pool 4, Upper Mississippi River 2004 Fish Collection Summary

This report is a bullet summary of the Long Term Resource Monitoring Program's fish collection efforts conducted by the Lake City Field Station on Pool 4, Upper Mississippi River during 2004. Information on changes in fish catch over all years can be obtained from the Graphical Fish Database Browser.

• 245 fish collections were conducted using six gear types (Table 2.1), with 204 from randomly selected sites and 41 from fixed sites.
  
  
• Side channel borders, backwaters, and main channel borders received the most sampling effort. (Table 2.1).
  
  
• Gear allocations among strata were the same for all three sampling periods except for one fewer trawl run during period 3.
  
  
• In 2004, water levels were lower than normal during April and early May (typically the peak flood period), but considerably higher than normal during late May and June. Water levels did not affect sample allocations (Figure 1.1).
  
  
• 30,921 fish representing 65 species and 3 hybrids were collected (Table 3.1). Historical fish distribution records for the Upper Mississippi River (Pitlo et al. 1995) document 99 fish species from Pool 4. To date the Lake City field station has collected a total of 89 species and 5 hybrids.
  
  
• The three fish species with the highest total catch were 22,334 emerald shiners, 1,913 bluegill, and 624 gizzard shad (Table 3.1).
  
  
• One paddlefish, a Minnesota threatened species, was collected. Eight blue suckers, six lake sturgeon, and four black buffalo, all Minnesota species of special concern, were also collected (Table 3.1).
  
  
• Mean catch-per-unit-effort and standard error for fish collected by the LTRMP using stratified random and fixed-site sampling for each stratum are shown in Pool 4 tables. Length distributions for selected species of fish are shown in Figures 1 to 17.