BRN 9-4 - Flipbook - Page 59
material may be cumbersome to retrieve due to the
extensive detail in the monograph.
found the population on average is comprised of 61 percent
adults, 6 percent sub-adults, and 33 percent cubs.
Population structure and dynamics are further elaborated in
several chapters of the book. These include chapters with
information on adult home-range characteristics, interactions between pumas, puma social organization, and
dispersal (or ranging) behavior. The researchers found that
the San Andres pumas constitute a metapopulation, which is
deÞned as a network of semi-isolated populations with
some level of regular or intermittent gene ßow among them.
Such populations depend on both emigration and
immigration to and from other groups for numeric and
genetic augmentation. This structure allows for the best
local adaptation to habitat while avoiding the adverse
effects of isolation, that of increasing genetic load from
inbreeding. In practical terms, it is important for wildlife
managers to provide corridors or land linkages to allow
contact between localized populations of pumas to maintain
genetic diversity and long-term survival.
A third audience for the book is encouraged as part of a total
conservation effort. This may include anyone with some
scientiÞc background, an interest in puma or big cat
conservation, and the desire to enter the milieu of
scholarship to better understand the subject. Many areas of
interest are well served, including those of natural resource
policy, zoo or mammalian biology, various aspects of
environmental study, as well as broader areas of public
education on such issues. The involvement of informed
advocates is essential, according to the authors, to help
transform the scientiÞc Þndings of this study into a format
the general public can understand and become responsive
to. Successful conservation efforts need the active interest
of the public. Such efforts require a broad-based acceptance
of our ethical obligation to protect natural systems,
combined with widely accepted knowledge based on
scientiÞc understanding of how natural systems work. Only
then can efforts to protect the big cats from extinction be
successful.
Several aspects of reproduction are discussed in a chapter
that gives information on fecundity rates, natality rates,
timing of births, mating system, gestation, birth intervals,
sex-ratios of offspring, nursing litter size, puberty,
philopatric females, icteroperous females, reproductive
behavior, and more. Information on mortality and survival is
given in another chapter in which the researchers establish
intra-species strife, with pumas killing other pumas, as the
dominant mortality factor in the population. This is not
unique to the San Andres pumas. Other chapters describe
diet, interactions with desert mule deer, and interactions
with desert bighorn sheep.
It may be hard for anyone other than a Þeld biologist to
appreciate the effort and commitment involved in this tenyear study. Pumas are among the most difÞcult of the large
terrestrial mammals to study since they naturally shun
human contact, have cryptic coloration and are crepuscular
and nocturnal. The only reliable method of study requires
tracking, then immobilization and capture of each puma.
Each is given individual identiÞcation, and all but cubs are
Þtted with a radio collar. Data is recorded from each animal.
After this processing, the subjects are released at or near the
site of capture. Movements are followed by radiotelemetry
both from light aircraft and on the ground. Fieldwork
continues year round, in this case ten days in the Þeld
followed by four days in civilization to regroup. Tracking
and capturing animals involves many skills unknown to the
ordinary researcher. These include map reading,
orienteering, rappelling, tree climbing, handling dangerous
animals, facing many other physical dangers, and living with
the privations of life in remote places. Surviving the
elements of weather, being lost, hunger, and tiredness are
all part of the experience. All of these add to the element of
adventure and romance and give epic proportion to this
study. Extensive knowledge of many aspects of Þeld
biology as well as courage and indomitable spirit are
prerequisites.
An experimental reduction of one part of the San Andres
puma population was made in late 1990 to mid 1991 to
allow study of population dynamics following a sharp
decline in resident pumas in a given area. One section of the
study area, designated as the Treatment Area (TA), 703 km.
sq., was utilized for this manipulation. Thirteen pumas were
experimentally translocated without injury to northern New
Mexico. Three others either died of natural causes or
disappeared. In all, the resident population of the TA was
reduced by 47 percent. The remainder of the study area was
designated as the Reference Area (RA), 1356 km. sq., in
which the puma population was not manipulated. The
undisturbed RA allowed the scientists to continue observing
in an area free of human manipulation. Various aspects of
population dynamics in the TA and RA were monitored and
compared during the remainder of the study. Much detail is
given in the results, but in essence, the population recovered
within 31 months. Recruits were from progeny born within
the TA, as well as from immigrants from both the RA and
from outside the study area. Recruits were basically of the
same number and sex as animals removed. This shows the
strong inßuence of mating system and social behavior on
puma population structure, and that protected populations
can quickly recover from a sudden and sharp decline.
The San Andres Mountains offer an ideal habitat for longterm basic research on pumas. The mountains are part of the
basin and range physiographic province, composed of
broken narrow ranges ßanked by large desert basins.
Isolation of the mountains by the surrounding desert basins
provide a self-contained ecosystem wherein none of the
large mammals migrate seasonally. Another factor makes
this area ideal for study. The land is restricted by the U.S.
Army and is relatively undisturbed by humans, minimizing
many confounding variables from human activity.
The Þnal two chapters of the book include discussion of
overall conservation and management of wild pumas. The
authors argue that protected zones of habitat, such as the
San Andres Mountains, are vital to prevent unnecessary
overkill of the puma. Safe corridors or land linkages are
needed to allow movement between the protected areas.
In this study, the scientists' Þrst hurdle was to censor the San
Andres puma population using the methods of capturemark-release and radiotelemetry tracking. They repeated
the censor process annually throughout the ten years and
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