| The Beaver Lakes Basin is centrally located within Pictured Rocks National Lakeshore adjacent to Lake Superior. Four locations were chosen to investigate fish migration patterns in response to climatic variables. Twenty two species of fish were captured; those exhibiting spawning migrations included white suckers (Catastomus commersoni) and northern logperch ( Percina caprodes). Adult white sucker entrance into streams for the spring of 2002 and 2003 was correlated with moonlength (rs=.540, p=.009) and photoperiod (p=0.017). Northern logperch entrance into the stream during the spring of 2002 and 2003 was correlated with mean water temperature (2002 rs=0.739, p=0.003; 2003 rs=0.610, p=0.46), degree-day (2002 rs=0.739, p=0.003; 2003 rs=0.793, p=0.004), and photoperiod (2002 rs=0.733, p=0.003; 2003 rs =0.763, p=0.002). Fish community analysis using Detrend Correspondence Analysis resulted in eigenvalues of 0.89 and 0.82, respectively with one time event fish captures removed and when included 0.98 and 0.65. Seasonal and location differences in fish community composition amongst sites existed between Lowney Creek and the Beaver Channel. Connectivity and usage of a suite of environmental variables for spawning likely allowed persistence and facilitated a diversity of life history adaptations by lentic fishes that would otherwise not be found within this basin. |
