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size classes recorded for females from_Par Pond (Murphy 197?; 1981; Brandt
1989), and Joanen (1969) has reported a positive correlation between body size and
reproductive output (clutch size) in this species. Nevertheless, if the reservoir is
refilled in the near future and proper nesting habitat is reestablished, a population
of large breeding adults should still be present.
The emigration of large adult alligators lollowing the drawdown of Par Pond
also has important implications for the safety of personnel working in the vicinjty
of this reservoir. tsy leaving Par Pond and moving elsewhere in the area, emigaant
alligators increase the likelihood that they will come to reside in locations where
contacts with site personnel will be more frequent. Just such a situation occurred
in the case of the largest male that emigrated from Par Pond in this study
(alligator F, Table 2). After resjding in Par Pond for a number of years, this
individual left the reservoir and began to frequent the vicinity of a construction
site below the retaining dam, where its aggressive actions toward workers at that
location required its subsequent capture and "harassment"(through radio
transmitter attachment by researchers). This aclion resulted in the animal's
moving further downstream out of the conslruclion area, to a point where its
contact with site personnel has now been eliminated and yel the animal's
movemenl can continue to be monitored/assessed from a safetv Doint of vie\^,.
The drawdown of the Par Pond reservoir evidently had little effect on the
ability of its remaining resjdent adult alligators to survive the winter months.
The winter survival of smaller alligators, particularly very young juveniles, in Ihis
population is less certain. 'l'he observations reporled here indicate that at ieast
some grorlps of young spent the winter wlth their mothers in subterranean dens
although these dens no longer contained water as a resull of the drawdown. Even
in the case of the elaborate den reported here holrever, it is not known whether
the group of young observed underground in F'ebruary survived for the remainder
of the winter months. In any case, female alligators in the Par Pond population
appear to be quite adaptable in caring for their nests and young, even under the
drastically altered environmental conditions p.oduced by the drawdown.
Despite the extraordinary efforls of lemales that tended nesls at Par Pond
in the summer of 1991, it is unlikely thal many hatchling alligators from that year
survived for long in the lowered reservoir with its almost complete lack of
vegetative shoreline cover. Although some halchlings may have been moved by
their mothers to other wetlands nearby, there are now probably few if any small
alligators still living in the reservoir ilself. Iiurthermore, as the water level
continues to be held at its lowered level, habitat conditions in those areas
previously used for nesting by the reservoirrs alligators, will remain unsuitable for
this purpose in the future, as the result of the loss of extensive stands of shoreline
vegetation, This suggests that the reservoir's alligator population will likely
experience a second consecutive year ol almost complete breeding failLfe, with
still additional years of failure to follow if the reservoir is not refilled. This
threat to both present and future reproductive output is probably the most
important single source of impact of the Par Pond drawdown upon its resident
alljgator population, and if continued through tine, it could have the effect of
irsetting backrr this populationrs numbers and age structure to those !vhich
characte.ized it in earlier years, as described by Murphy (f9??, 1981). To
h,hatever degree this may prove to be the case, the information provided by the
long history of previous studjes of these animals should be q vahable assel in
interpreting the importance of future changes in this reservoif and ils resident
alligator population.