accessible to fish per unit length of hver (Lerczak et al. 1994:5 and Figure 1). 

 Lerczak et al. (1994, 1995, and 1996) showed that river fish communities of the 

 three segments differed substantially enough to give segment designations 

 biological meaning. 



RESULTS AND DISCUSSION (Job 4) 



Before the fish sampling season began, all equipment was tested and 

 repaired as necessary. Due to the impending departure of project manager Lerczak. 

 training for new staff was more intensive than that needed in recent years; new staff 

 were trained in electrofishing methods and safety procedures (Job 1). 



All 27 sites were sampled between 26 August and 19 September 1996 (Job 

 2); total sampling time was 24.75 h (Table 1 ). Collected data were entered into a 

 computerized data base (R-Base software), rectified with original field data sheets, 

 and entry errors were corrected as necessary (Job 3). The original data sheets 

 were stored in a flame-resistant vault at Forbes Biological Station, Havana (Job 3). 



A. CONDITIONS DURING ELECTROFISHING RUNS 



Sampling was conducted in full daylight between 7:40 AM and 7:25 PM (Table 

 1) The ranges for physical measurements collected during the 1996 sampling 

 season were as follows: air temperature, 59.9-83.3 ^'F; v/ater temperature, 66.6-85.7 

 °F; dissolved oxygen concentration, 3.6-13.9 ppm, Secchi disk transparency, 6.7- 

 28.7 in; conductivity, 380-760 umhos/cm, surface velocity, 0.0-1 .5 ft/s; water depth, 

 0.1-5.0 ft. All values were within the ranges expected based upon previous sampling 



