Vol. 9, No. 2 
Page 6 
lauon r:ri:" 0f X ap r ° Sp ° nses of se * and a 9 e cohorts in the cottontail popu- 
lat.on on the area. These data are compiled from the capture records of individual 
bLn c'l; ::/rth kn r n ~ p r ent " during entire tra » ,n ° per^n™ ^ 
been captured on the area during a previous period and were recaptured on the aroa 
during a later period. This method eliminates bias due to cohort-re1ated rates of 
immigration and mortality. re.area rates ot 
. Capture frequencies for individual rabbits varied from zero to nine. These 
data were transformed using X' = /x + and the significance of differences between 
average capture frequencies was tested using a t - test. between 
sex-relatld S d W ?f e m ° re freqUe " t,y than males in all age-classes. These 
tnnJn Iw w d,f ^ e '' ences were significant at the 95 percent level of confidence for 
known-adults and for the artificial classification of probable-adults, but only at 
the 90 percent level of confidence for juveniles. Y 
about^foui^tn'f* the and 5-month age-class were captured most frequently, being 
about four to five times more trappable than adults of the same sex Above this 
d^icuTt" capture^ deCreaSed pr °^ ess V • Adult males were especially 
lation! Septembe^through'^February^l 964 - 65 3 and S 1965 - 66 ^ COtt ° ntaM p ° pu ' 
Age-Class* 
Samo 1 
e Size 
Averaqe Capture 
F requencyt 
Reference 
Va 1 ue 
Ma 1 es 
Fema1es 
Ma 1 es 
Fema1es 
Value of t 
4-5 Months 
30 
20 
2.0 
2.8 
1 .49 
ns* 
6-7 Months 
31 
23 
1 .2 
1 .7 
1-35 
ns 
8-9 Months 
16 
15 
1 .1 
1 .2 
0.38 
ns 
A11 Juveni1es 
Probable- 
77 
58 
1 -5 
2.0 
1 .86 
t .io =l - 66 
adu1ts 
41 
42 
0.8 
1 .4 
2.12 
fos ' 2 - 00 
Known-adults 
52 
88 
0.4 
0.7 
2.17 
'.os " 1 ' 98 
the studv p rnhaKi "* ' , eU “P on Doa Y weights at times of first capture during 
olrlj dy ' Probab,e - adults could not be aged accurately and are either adults or 
older juveniles. Known-adults had been tagged during a previous year 
L. C "?rr?n f : eqUenC * e ? are the numbers of captures during a trapping period 
periods are cons-rf 0 ” h a , n ' ma]s wblch were known-present during entire trapping 
periods ere considered (see text). 
f ns = not significant. 
