20 



Alvin L. Braswell and Ray E. Ashton, Jr. 



Fig. 2. All known records for Necturus lewisi. Solid dots are localities sup- 

 ported by voucher specimens; small hollow dots are sight records believed valid; 

 and large hollow circles are localities supported by voucher specimens with 

 imprecise locality data. 



Table 1 shows the capture success for N. lewisi in different category 

 streams. The capture success rate was significantly higher in medium 

 and large streams than in little and small streams. No significant differ- 

 ence in capture success rate between little and small streams was noted, 

 but a trend toward greater success in larger streams was apparent. 



Frequent fluctuations in water levels caused by precipitation made 

 it difficult to obtain meaningful depth measurements. Therefore, no 



Table 1. Comparative Necturus lewisi capture success in streams of different 

 relative widths (m, approx.). Numbers in parentheses are number of 

 sampling efforts for each stream width given; total samples = 749. Per- 

 centages are success rates for each stream width. 



Relative stream width 



Capture 

 success 



Little 

 <5m 



(88) 

 (9) 



9.3% 



Small 

 5.5- 15m 



(309) 



(55) 



15.1% 



(364) 



Medium 

 15.5 - 25m 



(120) 



(55) 



31.4% 



Large 

 > 25.5m 



Negative 

 Positive 



(77) 



(36) 



31.9% 



Totals 



(97) 



(175) 



(113) 



