WILKINS ET AL.: FLORIDA PANTHER MORPHOLOGY


Caloosahatchee River is an effective barrier between north and south in the
southwestern part of the state (Maehr 1997).
 Distribution of panthers in south Florida is limited by the availability of
 suitable habitat and prey (Smith and Bass 1994). Between 1986 and 1991, radio
 telemetry studies revealed that female panthers in the Everglades utilized home
 ranges entirely east of the Slough, as did their female offspring (Bass 1997). In
 southwest Florida, females remained in or near the home ranges of their probable
 mothers (Maehr et al 1991). Young female recruitment into natal home range is a
 pattern repeated in other cougar and felid populations. Due to high home range
 stability for adult males, vacant home ranges for young dispersing males are
 limited, and mortality is greatest in subadult and non-resident males (Maehr et al.
 1991). High rates of aggressive encounters between males of Florida panthers
 compared to other cougar populations, and the highest mortality factor of male
 cougars in Florida (Dunbar 1997), may be a further indication of limited dispersal
 opportunity as a function of suitable habitat.
 A combination of factors that include cyclically high water levels in Shark
River Slough, limited habitat availability, and the dynamics of puma behavior
could explain the high degree of isolation that existed between the two populations
of cougars in south Florida and that would have resulted in a reduction in gene
flow and shared morphologic traits. With this recent extended dry period recorded
in Florida, the effects of introgression may become more conspicuous as animals
cross more freely between the two refuges.
 Frequencies of whorls and kinked tails have changed over time. Four of six
cats collected and studied by Outram Bangs between 1896 and 1898 did not have a
mid-dorsal whorl. Among recent panthers of known origin from the Big Cypress
Swamp between 1972 and 1987, all had kinked tails (n=30), and 25 of 27 (92%)
had the back whorl. In 1986-1987, six panthers were captured in the Everglades
National Park (ENP); none had a kinked-tail and only one had the whorl. In 1988
the first BCS animal with a straight-tail and whorl was documented (#25 rogue).
By early 1990, four straight-tailed panthers (three of which had whorls) were
documented in the BCS and the first cat from ENP (#39) with both the whorl and
the kink was captured in ENP (Roelke 1990). This suggests there has been more
mixing between the two areas in recent years.
 The presence of a mid-dorsal whorl and kinked-tail clearly identifies a cat as
being from the native Florida population, regardless of the genetic interpretation.
The expression of these traits in the Florida populations in high frequencies has
been considered a morphologic indicator of inbreeding and reduced levels of
genetic variability. Of six North American subspecies of cougar, Roelke et al.
(1993) demonstrated that the authentic Florida panther (excluding Everglades cats)
exhibits less variation than any other puma subspecies with the fewest polymorphic
loci (P) 4.9%, and low heterozygosity (H) with 1.8%, compared to (P) of 27% and
(H) of 1.8-6.7% for other subspecies. This is nearly as low as the level of allozyme
variation reported in the cheetah. This condition has undoubtedly resulted from