114 



Timothy S. McCay, Joshua Laerm, M. Alex Menzel 

 and William M. Ford 



Table 1 . Number of captures of four species of shrews using two pitfall transect 

 designs, selective and linear, at the Coweeta Hydrologic Laboratory, July 1994. 

 Traps in selective transects were positioned 5-m apart next to structures such as 

 down logs and rocks. Traps in linear transects were set 5-m apart in a straight 

 line. 



Transect Type 





Selective 



Linear 





Selective:Linear 



Species 



(TN = 3,360) 



(TN = 3,360) 



Total 



Ratio 



Blarina brevicauda 



25 



8 



3 



3.1:1 



Sorex cinereus 



208 



78 



286 



2.7:1 



Sorex fumeus 



116 



36 



152 



3.2:1 



Sorex hoyi 



9 



4 



13 



2.3:1 



Total 



358 



126 



484 



2.8:1 



In 2,240 TN at selective transects in 1995 we captured 124 individuals 

 of the same four species captured in 1994 (Table 2), whereas linear transects 

 yielded 52 individuals. Similar to the 1994 data, we captured 2.4 times as many 

 individuals in selective as in linear transects; however, there was greater varia- 

 tion in this ratio among species than in 1994. In 4,040 TN at drift-fence arrays 

 we captured 81 individuals of the same 4 species. Capture frequencies observed 

 at drift-fence arrays differed from both types of transects, and ratios involving 

 drift-fence arrays varied markedly (Table 2). Consequently, the distribution of 

 shrew captures among sampling methods varied in 1995 (G 2 = 17.849; P = 0.001; 

 df = 4). 



We were able to construct four independent, four-fold tables using the 

 data collected in 1995. Two of the tables compared captures of S. cinereus and 

 S. fumeus between the two types of transects (G 2 = 0.021 ; P = 0.884; df = 1) and 

 between transects (both combined) and arrays (G 2 - 3.049; P = 0.081; df = 1). In 

 neither case did the data support dependence; therefore, capture frequency of 

 these species was not markedly affected by trapping method. 



The remaining four-fold tables compared Sorex spp. to B. brevicauda 

 with respect to trap arrangement. The first of these, a table comparing Sorex spp. 

 and B. brevicauda captures by transect type, indicated that capture frequencies 

 for these two taxa differed between the two methods (G 2 = 6.061; P - 0.014; df 

 = 1). The odds ratio for this table was greater than unity (9 = 3.17; Z = 2.409; 

 df = 163), indicating that Sorex spp. were more likely than B. brevicauda to be 

 captured using selective transects. The second of these tables compared Sorex 



