WASSMER ET AL.: SOUTH-CENTRAL FLORIDA BOBCAT ECOLOGY


 Demographic Characteristics


 Density.- Estimated overall mean density of bobcats for the period April
1979 to August 1981 was 26 individuals/100 km2. Mean densities of adult
males, adult females, and juveniles during this period were 5, 8, and 13/100
km2, respectively. Overall densities in different periods of the study ranged
from a maximum of 42/100 km2 in the 1 July-25 October 1979 interval to a low
of 14 in the 29 February-30 April 1980 interval (Table 2). Numbers of adult
males ranged from a high of 7/100 km2 in summer-fall 1979 to 0 in late winter
1980. Maximum and minimum densities of adult females were 12/100 km2 in
spring-early summer 1979 and 6 in fall 1980. Male density estimates for the
different time periods ranked significantly lower (U1212 = 7.5, p < 0.01,
2-tailed) than those of females, with males showing a more pronounced decline
in late fall and winter 1979-80. Male density was still below the original level at
the end of the study. Highest (26/100 km2) juvenile density was attained in
summer-fall 1979; no mobile juveniles with resident females were recorded on
the study area during the 29 February-30 April 1980 interval. Numbers of
juveniles were relatively high in 1979, declined through 1980, and increased
again in 1981.
 The overall mean density of bobcats in this study was half of that (52/100
 km2) estimated by radioisotope marking in northeastern Florida by Conner
 (1982). Density estimates based on radiotracking elsewhere in the southeast
 include 77-116/100 km2 in Alabama (Miller and Speake 1978), 13-19/100 km2
 (Kight 1962), and 58/100 km2 (Provost et al. 1973) on the Savannah River
 Plant in South Carolina, and 9-18/100 km2 in Virginia (Progulske 1952).
 Densities of bobcats in the southeastern United States tend to be higher than
 values reported for northern populations and are broadly comparable to those
 from the western United States (McCord and Cardoza 1982). However,
 detailed comparisons between most published population data are not possible
 because of the variety of techniques and assumptions involved in density
 estimates by different workers.

 Sex and Age Ratios.- The overall mean age ratio based on the bobcats
 known or assumed to be present during the 12 time intervals was 1.00
 juvenile/adult (Table 2) compared with a 0.42 juvenile/adult capture ratio.
 The difference reflects the difficulty of trapping juveniles still in the company
 of their mother. Juvenile/adult ratios closely tracked the population trend,
 being high from July 1979 to early February 1980, low during most of 1980, and
 increasing from March to August 1981. Adult sex ratios over the 12 time
 intervals ranged from 0 to 1 male/female (X = 0.64 male/female, Table 2).
 The proportion of adult males to females declined sharply from late October
 1979 to early February 1980 then increased to a fairly stable level by the