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in many places, there was no €vidence thal eilher animal had been consumed by the attrcker.
While it cannot be shown that these alligalors did not die trom natural causes! it would seem
vcry unlikely that rcsident aligators would have so violently attacked the already dead carcasscs
of lh€se lwo animals wilhout the intenlion of feeding upoo them to some extent. Intraspecific
aggression resultirg in dsrth of one of thc comb,rt:rnts is well-known in a number of species of
crocodilians including the American alligator especially in the case of territorial males (Lang
1989; Pooley ard Ross 1989). Female'female ierrilorial aggression has also been recorded by
Pooley rnd Ross (1989), larticularly during fhe breeding/nesting season that included the period
when the adull female emigrant alligatorwas found dcad in Pond B (Table 2). No dealhs of
resident alligators were re€orded in any of ths wetlands surrounding Par Pond during the coufie
of this study. These considerationsuggesthat onc of the likely etlects of tbe Par Pond
drawdown has been to cause an incre.se in the morlaliE of adult ^lligatorc of both sex€s thal
enigrated from the shrinking reservoir and were subsequendy killed in aggressivencounrers
with resident aligators in nenrby h^bitals to which they h:d noved.
Only one aligator death was recordcd in P^r Pond during the course of this study. A
juvenile alligator measuring 0.96m in total lcnglh was found in a torpid stAte on 18 February
1991 on the mudnals. This ,nimal was loc^led 1l5m to the east of the entrance of a winter
den, as will be described later (Figures 6 and 7), :rnd was found on the edge of a small pool (5m
diameter) in the mudflal, tbat had the appearancc of having been excavated by the acrions of a
'arger alligator. This jnvenile was considernbly larger tban any of the young that had been
observed in the den but was very lhin and missing the distal portions of both forelimbs which
appeared to havc been amputated in a struggle with I conspecific or some other predator. 'fhis
juvenile was rotumed ro the laboratory for furrher obscrvnlion where il proved active and aterr.
It was marked and released at the site of c.pture lwo days later and was not seen again until ir
was found dead At the srme localion on 27 March 1991. 'nrc discovery of an alligator of this
small size in the open, during the winter months, is an unusual occurrence af Par Pond :rnd
suggests the possibility of stress"induccd winter movemenl related to the presently lowered water
level in the animal's habitat.
The c^use of the observed emigralions wff likely conspecific aggression which
undoubtedly increased as the f:rlling watcrs reduced the sizes of territories available to resident
animals of Par Pond. Twice as mnny males as lemales were documented as leaving Par Pond
and it is indeed lhe males which would be expected to show the greatesl incra:tse in conspecific
lenilorial aggression as the reservoit was drawn down. An extended aggressivencounter
beNeen two large alligators was observed in shrllow water nlong lhe eastern shore of the Main
Lake in mid-September 1991 (F.W. Whicker, pers.comm.). This encounter was the firsr of ils
kind ever recorded for the Par Pond alligrtor population and involved biring, rolling and tailslapping,
but neither combarant was apparently scriously injured.
Winterine Ecolosv:
The American aligator h.s been reported lo make frequent use of den structures
during the winter months to provide protection from low lemper^ture cxtremes. The use of
such dens, that are usually localed either in shallow water or ^l the water's edge wirh submerged
entrances, has been reporled from lhroughout the species' range, including Florida (coodwin
and Marion 1979), Texas (Kellogg 1929), buisiara (Mcllhenny i9l5) rnd Norlh Carotina
(Hagan et dl 1983).