EDWARDS ET AL.— MAMMAL ABUNDANCE AT FORT HOOD 
17 
Table 8. A comparison of relative abundances of medium-sized mammal species obtained from live- 
trapping and spotlight surveys. Analyses involve comparisons of live-trapping transects and spotlight surveys 
which were conducted over the same routes. Relative abundances were calculated by dividing the number of 
individuals of a species observed on spotlight surveys or trapped in live traps by the number of kilometers over 
which surveys or live-trapping were conducted. Relative abundances are expressed as the number of individu¬ 
als of a species per kilometer. Species abbreviations are: Dv = Didelphis virginiana, PI = Procyon lotor, 
Mm - Mephitis mephitis, Ba = Bassariscus astutus, Sp = Spilogale putorius, Nf— Neotoma floridana, Sn = Sciurus 
niger, Sf— Sylvilagus flondanus, Uc — Urocyon cinereoargenteus, Cl — Canis latrans, andLr = Lynx rufus. 
Dv 
PI 
Mm 
Ba 
Sp 
Nf 
Sn 
Sf 
a 
Lr 
Uc 
Upl 2 
0.03 
0.14 
0.22 
_ 
0.03 
... 
0.03 
Line I 
0.13 
1.05 
0.43 
0.28 
— 
... 
— 
... 
0.10 
0.03 
0.31 
Rip 2 
1.00 
_ 
_ 
... 
... 
Line 1 
0.08 
0.21 
0.13 
0.08 
... 
... 
... 
... 
... 
— 
0.05 
Rip 1 
0.17 
0,42 
0,03 
_ 
... 
0.17 
0,03 
Line 2 
0.08 
0.18 
0.08 
— 
... 
... 
— 
... 
... 
... 
0.03 
Sav 2 
_ 
0.42 
_ 
0.08 
Line 3 
0.08 
0.15 
0.10 
0.08 
... 
... 
... 
... 
... 
... 
0.18 
Sav 1 
0.10 
0.10 
0.10 
... 
0.05 
Line 5 
— 
0.27 
— 
— 
— 
— 
... 
— 
... 
0.07 
0.07 
unclear why no ringtails were captured in presumably 
more suitable habitat. 
Eastern woodrats were collected in all three ma¬ 
jor habitat types. All feral cats were collected in savan¬ 
nah habitats, while essentially all eastern spotted skunk 
captures were recorded in upland habitats. 
Seasonal variations have been shown to influence 
trap success in many studies (Davis, 1977; Greenwood 
et ah, 1985; Moore and Kennedy, 1985). Davis (1977) 
found capture mean in the fall was significantly lower 
than in the spnng and summer, but the same as in winter. 
Mean capture rates in winter for this study were similar 
to mean capture rates in spring and summer. Moore and 
Kennedy (1985) indicated that, during the spring and sum¬ 
mer months, when food was readily available, trap suc¬ 
cess for raccoons was low. When food is still available 
during the autumn, raccoons were gaining weight and 
apparently feeding more in preparation for winter, and 
winter rates are usually high because of lack of food. In 
this study, no differences in overall capture rates were 
detected among seasons. Because of mild winters in this 
region ofTexas, food availability may not vary greatly by 
season, which could explain why capture success did not 
vary seasonally during this survey. 
No significant difference in overall capture mean 
was detected between medium and large traps for all spe¬ 
cies analyzed with the exception of raccoons. Raccoon 
capture means varied significantly among trap sizes in 
all but one comparison (Upl 1 vs. Upl 2). Twenty of 31 
raccoon captures (64.5%) were recorded in large traps 
with no raccoon captures in small traps. Mean capture 
rates for raccoons and opossums varied significantly be¬ 
tween large and small traps but not between medium and 
small traps. No species were captured in only large traps. 
Because no significant difference was detected between 
overall capture means of large and medium traps, the lat¬ 
ter would be preferable for medium-sized mammal sur¬ 
veys because they are less expensive and easier to carry 
into the field. The lower capture rates of small traps 
were probably due to the physical dimensions of the traps 
and animals. Although small traps recorded the lowest 
number of captures, they were the only size of trap which 
captured eastern spotted skunks. 
