Effort Log as part of the Bird Studies 
  Chris Ribic and Erik Chapman, SIs 
    Notes: N = Night; D = Day; 
      StartCode: 0=Start; 1=End; 0.5=change in conditions 
      Visibility Code = see documentation 
      Precipitation: 0=none; 1=fog; 2=rain; 3=snow, including sleet or hail 
      Cloud cover = eighths 
      Ice Concentration = tenths 
      Primary Ice cover = see documentation