|
-"IEEVI-U
of the
FLORIDA
MUSEUM OF
NATURAL HISTORY
ECOLOGY OF WHITE-TAILED DEER
IN EASTERN EVERGLADES NATIONAL PARK
AN OVERVIEW
Tommy R. Smith, Cynthia G. Hunter,
John F. Eisenberg, and Melvin E. Sunquist
Volume 39. No. 4 pp. 141-172
UNIVERSITY OF FLORIDA
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ECOLOGY OF WHITE-TAILED DEER IN EASTERN
EVERGLADES NATIONAL PARK--AN OVERVIEW
Tommy R. Smith', Cynthia G. Hunter2,
John F. Eisenberg3, and Melvin E. Sunquist4
ABSTRACT
A population of white-tailed deer (Odocoileus virginianus seminolus) was studied
in the eastern Everglades National Park from 1987 to 1992. The data for the interval
January 1987 to June 1991 are summarized in this publication. During this interval, from
35 to 40 deer were monitored annually. Deer were captured utilizing a shoulder-held gun
projecting a net, and fired from a helicopter. Captured deer were fitted with a radio collar
and, thereafter, located by telemetry from both the ground and a fixed wing aircraft.
Aerial locations were logged to a recognizable hectare square. Minimum convex polygons
of deer home range use then were determined. Individual females occupied ranges of
approximately 37 ha and males 113 ha, but seasonal differences in range use indicated
that some males may have an annual range exceeding 12 km2. There was considerable
overlap of home ranges, especially among individual females and their presumptive
offspring. The population density was estimated to be 0.68 deer/km2. Adult females
produce a single young; twinning was not recorded. During the course of this study,
recruitment into the population was low. Mortality rates varied from year to year,
especially for young fawns. The population appeared to be stable. During the course of
the study, the panther (Puma concolor) was present. Deer comprised 57 percent of 99
identified panther kills in the eastern Everglades National Park and adjacent areas. Adult
' T. R. Smith was formerly a Wildlife Scientist at U.S.N.P., Everglades National Park, and now resides in
La Neuve, Belgium.
2 C. G. Hunter is a graduate student in Zoology at Witwatersrand University, South Africa.
3 J. F. Eisenberg holds the Ordway Chair of Ecosystem Conservation at the Florida Museum of Natural
History and School of Forest Resources and Conservation, University of Florida, Gainesville FL 32611-
7800 U.S.A.
4M. E. Sunquist is Associate Professor, Department of Wildlife Ecology and Conservation, University of
Florida, Gainesville FL 32611 U.S.A.
Smith, T. R., C. G. Hunter, J. F. Eisenberg, and M. E. Sunquist. 1996. Ecology of white-tailed deer in
eastern Everglades National Park-an overview. Bull. Florida Mus. Nat. Hist. 39(4):141-172.
142 BULLETIN FLORIDA FLORIDA MUSEUM NATURAL HISTORY VOL. 39(4)
bucks with a mean age of 5.5 years were the dominant age/sex class killed (47% of all
deer). We conclude that, although densities of both deer and panthers are low in the
eastern Everglades National Park, they were normal and near carrying capacity or stable.
RESUME
Se estudi6 una poblaci6n de ciervos de cola blanca (Odocoileus virginianus
seminolus) entire 1987 y 1992 en la parte oriental del Parque Nacional Everglades. Esta
publicaci6n sumariza la informaci6n obtenida entire enero de 1987 y junior de 1991.
Durante este period se monitorearon 35 a 40 ciervos al afio. Los ciervos fueron
capturados usando una red projectada por un rifle desde un helic6ptero. A cada ciervo
capturado se le coloc6 un radio collar gracias al cual los animals pudieron ser localizados
usando telemetria desde tierra o desde una avioneta. Las localizaciones obtenidas desde
la avioneta fueron registradas en cuadriculados de una hectArea. Los ambitos de hogar de
los ciervos fueron entonces determinados usando poligonos convexos minimos. Hembras
y machos ocuparon ambitos de hogar de 37 y 113 Ha, respectivamente. Variaciones
estacionales indicaron que algunos machos habrian tenido Ambitos mayores que 12 km2.
Los ambitos de hogar se sobreimpusieron considerablemente. Las hembras y sus
presuntos descendientes ocuparon ranges de hogar sobrepuestos en gran media. La
densidad poblacional fue estimada en 0.68 ciervos/km2. Las hembras adults parieron
una sola cria no registrAndose mellizos. El reclutamiento de la poblaci6n fue bajo durante
este studio. La tasa de mortalidad vari6 de afio a afio especialmente en los cervatillos
j6venes. La poblaci6n apareci6 stable. Pumas (Puma concolor) estuvieron presents
durante el curso de este studio. Un 57% de las 99 press capturadas por puma e
identificadas en la parte oriental del Parque Nacional Everglades fueron ciervos. Ciervos
adults macho de 5.5 aflos en promedio fueron la clase de edad y sexo dominant (47% de
todos los ciervos). Nosotros concluimos que aunque la densidad de ciervos y pumas en la
parte oriental del Parque Nacional Everglades es baja, ambas poblaciones son normales y
se encuentran cerca de su capacidad de carga.
ACKNOWLEDGEMENTS
The principle investigators (JFE and MES) would like to thank the many
participants, sponsors, and advocates of this lengthy project, especially the National Park
Service and its employees. Sonny Bass' cooperation was essential during the final
preparation of this report.
The majority of the field work was organized and conducted by Tommy Rae Smith.
He deserves credit for continuing aerial locations of deer through many hardships.
Cynthia Hunter completed her master's thesis research on the reproduction of the white-
tailed deer in the Everglades National Park (ENP) and aided greatly in the preparation of
the final report. Jos6 Fragoso and Tadeu Oliviera served as part-time field assistants.
People in Homestead and ENP who were outstandingly helpful were so numerous that we
fear we may leave some unmentioned, but we must particularly thank Wyatt Enterprises'
SMITH ET AL.: WHITE-TAILED DEER IN ENP
pilots, Lynch Incorporated pilots, Sue Husari and the Fire Cache, John Ogden, Frank
Draughn, and W. B. Robertson.
Many thanks are due to the generous Geographical Information System (GIS)
computer specialists of the Department of Urban and Regional Planning at the University
of Florida, especially David Lambert, who took the initiative to make room for the 200
MB of data from the park so that Cynthia Hunter could sift through it and absorb some of
his good teaching.
This research was supported with funds from U. S. National Park Service Grants
5602519-12 and 5602497-12 under CA-5280-5-8004. Some supplemental funding
derived from the Katharine Ordway Chair of Ecosystem Conservation, University of
Florida, Gainesville. The National Fish and Wildlife Foundation contributed monetarily
as well.
SCOPE AND HISTORY
As increasing attention, funds, and research efforts have been applied
to the understanding, restoration, and management of the Everglades
ecosystem, a proposal was approved to elucidate interactions between deer
(Odocoileus virginianus seminolus), Florida panthers (Puma concolor
coryi), and the vegetation, all thought to be unique and essential
components (Eisenberg and Sunquist 1986). The Florida panther, an
endangered subspecies, feeds primarily on deer and feral hog (Sus scrofa),
but the hog has been eliminated from National Park land; thus in Everglades
National Park (ENP), deer potentially provide the only large prey available
(Maehr et al. 1990; Alvarez 1993). However, there has been widespread
concern that the deer in the Everglades are at insufficient density and of
such small body size that they are possibly an inadequate source of
sustenance for the panthers (Belden et al. 1988). Information on deer
population dynamics was considered essential to management of the
panther. The Panther Recovery Plan (USFWS 1987) has been an important
ongoing aspect of park research, and this deer study was proposed and
approved to provide essential information.
Physiological, behavioral, and reproductive differences between the
race O. v. seminolus and northern white-tailed deer have long been
suspected (Richter and Labisky 1985), but little was known of the ecology
of South Florida deer. Only one in-depth study of the natural history of this
subspecies had been conducted prior to the present research effort (Loveless
1959; Loveless and Ligas 1959) with a later study by Schemnitz (1974).
Deer in ENP are a sedentary (non-migratory) population. No hunting
has been allowed anywhere in ENP since its establishment in 1947, but
hunting continued uninterrupted in the forest reserves north of the park.
144 BULLETIN FLORIDA FLORIDA MUSEUM NATURAL HISTORY VOL. 39(4)
Mortality factors acting on deer in ENP were presumed to be panthers,
bobcats (Lynx rufus), poachers, cars, and natural health factors, including
possibly nutrition, contaminated surface water, disease, and parasites. In
this regard we were interested in examining the relative impact of these
various mortality factors, the possible differential impacts on different age
classes of the population, and the implications for management when
community interactions were considered.
Originally a comparison of hunted and unhunted populations was
proposed (Eisenberg and Sunquist 1986). Richter and Labisky (1985)
found a significant difference in deer herd productivity on hunted vs.
unhunted sites of similar habitats within Florida. Generally, herd
productivity was higher on hunted sites, although densities, pregnancy rates,
fetuses/doe, and age structures varied between sites. Their study provided
strong impetus to study and manage the various sub-populations of deer and
panthers across Florida on a site-specific basis. This report summarizes a
study focused on the unhunted ENP population south and east of Shark
River Slough. A parallel study from 1989 to 1992 directed by R. F.
Labisky focused on the hunted populations in Big Cypress National
Preserve and adjacent deer in ENP north of Shark River Slough.
Deer density in the Everglades appeared lower than elsewhere in
Florida or the Piedmont (Harlow and Jones 1965; Newsom 1984), but the
Everglades deer had not been censused thoroughly. A survey-based census
of deer and panthers in ENP in 1970 (Schemnitz 1974) estimated 8
panthers and 1500 deer in the then 5261 km2 ENP, yielding a density of
0.29 deer/km2. Densities were even lower in the Water Management
Conservation Areas 2 and 3 north of the park at 0.10 deer/km2 (Schemnitz
1974). This difference was possibly due to more intensive hunting and
more severe flooding there (Loveless 1959). The only other authors to
survey O. v. seminolus and as part of a state survey (Harlow and Jones
1965) found the Everglades ecosystem the one least able to support deer in
all of non-urban Florida. This was mainly believed to result from the low
nutrient availability for deer in the predominantly flooded prairie habitats.
Although seasonally flooded bottomland hardwood forests are thought of as
the best deer habitat in the southeast (Sigler-Eisenberg and Eisenberg
1985), very little of this habitat exists in the Everglades (Fig. 1).
Since the early 1970s the Everglades deer herd has apparently declined
and remained at a very low density, relative to historical populations in the
Everglades (F. Dayhoffpers. comm. 1989). The only recorded large-scale
The original extent of the Everglades wetland.
^ The study site, centered on Taylor Slough. 2 l
Canal, with burm and road. so n.
.. Edges of aquatic flows,
Shark Slough & Taylor Slough.
L Big Cypress National Refuge. \
2. Everglades National Park's terrestrial portion.
Figure 1. Southern Florida and the now partitioned and partially drained Everglades National Park wetland.
146 BULLETIN FLORIDA FLORIDA MUSEUM NATURAL HISTORY VOL. 39(4)
die-offs were caused by tick eradication efforts in the 1930s, overhunting in
the conservation areas in the 1960s, and excessive flooding in 1957-1958
and in 1982-1983. In part the low densities were attributed to a lower
fecundity in the deer of the southern flooded region than even in the rest of
Florida (Harlow 1972), despite the state as a whole having deer of lower
fecundity than other deer herds north of Florida (Harlow and Jones, 1965).
These authors attributed the lower fecundity to possible mineral deficiencies
from the food plants growing on infertile soils (Deuver et al. 1986; Kushlan
1990). This study and the concurrent work on deer in the Big Cypress
National Preserve compared densities, reproductive output, predation, and
other mortality factors affecting deer in the Everglades.
STUDY SITE
The terrestrial habitats of ENP, covering 5660 km2, are mainly prairies
dotted with tree islands of various sizes and pine flatlands. The Everglades
is classified as 65% tropical savannah (USFWS 1979), but not much is
known regarding changes in this ecosystem's plant or animal components
since water control measures were implemented. The entire region can be
considered a hyperseasonal savannah (Sarmiento 1984), controlled by
annual flooding that used to coincide with the rainy season of May through
October, and now is managed by outputs from canals (Fig. 1) in a "rainfall
simulation strategy." Although this management scheme has produced wet
and dry seasons somewhat similar to the natural system (Walters et al.
1992; ENP unpubl. hydrology data), the volume of water has been slowly
decreased over the last 50 years, diminishing both high and low extremes of
depth that occur seasonally in the park at the southern end of the wetland
(Hunter 1990).
The Everglades ecosystem is believed to be stable in plant species
composition, due to the periodic disturbance of fire and water (Robertson
1953; Loveless 1959). The savannah's prairies are two types. Wet prairies
are dominated by one or more of the sedges sawgrass (Cladium
jamaicense), spikerush (Eleocharis sp.), and beakrush (Rhynchospora sp.).
These prairies are dotted with tree islands, or "hammocks," composed of
tropical hardwoods or "domes" of cypress (Taxodium distichum). Dry
prairies are dominated by the grass called "muhley" (Muhlenbergiafilipes)
and scattered with occasional or clumped hardwoods, especially willow
(Salix caroliniana), and where hydroperiod becomes longer, with the herbs
common to wet prairies. Parts of dry prairies have no hydroperiod (above
SMITH ET AL.: WHITE-TAILED DEER IN ENP
ground flooding) at all in some years. Scattered large areas of pinelands are
nearly monotypic (Pinus elliotii var. densa) forests with thick understories
dominated by Sabal palmetto (Fig. 2).
The two areas of the park where water flows almost continuously year-
round are called "sloughs," and the study efforts of this report centered
around Taylor Slough. This site allowed access to the research facilities
and the "hole in the donut." This latter site is a disturbed area now invaded
by dense stands of exotic trees, such as Schinus terrebinthifolius and
Melaleuca quinquenervia. More details of vegetation can be found in
Deuver et al. (1986) and Hunter (1990). Ongoing NPS studies of fire
management and regeneration, flooding regimes, and flowering phenology
were simultaneous with this study and provided useful habitat information
in the form of unpublished data from Park Service personnel.
The climate is technically sub-tropical: Seasonality is dictated by
variation in rainfall, not temperature, although a frost occurs on an average
of once every ten years. Rainfall averages 148 cm per year, 81 percent of
which falls during the wet season, usually from late April through October
(Schomer and Drew 1982; Deuver et al. 1986). The intensity (+ 34 cm per
year), timing, and duration of the wet season are highly variable beginning
April, May, or June and extending through August, September, or October.
Rainfall often occurs with two noticeable peaks, one in May or June and the
second in September (37 years ENP unpubl. hydrology data; Schomer and
Drew 1982). The effects of water on deer health and the synchronizing of
herd productivity were among the questions of interest addressed in this
study.
METHODOLOGY
General methods are described below, and more details concerning
methods are included in the Results section.
Capture
Initially, dartguns shot from blinds, buildings, and a truck were used in
an attempt to capture deer, but this method proved unsuccessful due to the
availability of thick cover for the deer. Box traps were not utilized. After
frequent visual sightings of deer in open prairies, the technique of utilizing a
shoulder-held gun projecting a net fired from a helicopter was attempted
(Barett et al. 1982; Chardonnet and Charity 1992). A gunner
148 BULLETIN FLORIDA FLORIDA MUSEUM NATURAL HISTORY VOL. 39(.
111111 = Dense Trees
depth gauge
depth, rainfall, and flow gauge
abandoned, partially filled canals
canal, with burm and road
slightly elevated road only
pinelands
hardwood hammock
dense exotic shrubs
Figure 2. The study site in the Taylor Slough area of Everglades National Park, and the
prairies classified as either "wet" (W) or "dry" (D). "Intermediate" (I) prairies were wet
in 1988 and dry in 1989.
SMITH ET AL.: WHITE-TAILED DEER IN ENP
experienced in the use of helicopter net-gun techniques was invited to
demonstrate, and 19 deer were caught in 15 hours of flight. This became
the chosen technique for capture and was subsequently used to obtain the
sample of deer collared, as represented in Table 1. Deer were also
recaptured using this technique.
Chase flights by helicopter were limited in duration to a maximum of
about 10 minutes, varying slightly with environmental temperature.
Temperature and chase time were the key factors limiting capture-related
mortality, as long chases may result in capture myopathy. No chemical
immobilization was necessary: Deer were immediately tied, blindfolded,
freed from the net, and held on the coolest ground available for an average
of 20 minutes while measurements were taken and a radio collar affixed.
The pulse and respiration rates of captured deer were monitored while the
animal was restrained.
Data collected on each captured animal included: Date, time, location,
habitat, other animals nearby, total length, tail length, head length, ear
length, zygomatic width, neck circumference, height at shoulder, girth,
weight, hind foot length, front foot length, toe length, sex, tooth condition,
tail fat index, muscle index, pelage condition, ectoparasite index, and
samples of blood and vital signs taken. These data were collected by very
few personnel, so the subjective assessments were similar for each animal.
Stratification of Sample and Sampling Scheme
After the initial sample of 45 deer was obtained in 1987 by somewhat
random searching of open prairies around the HID area, deer could be
selected visually and not chased if of an age or sex that was not needed in
the sample. While not completely random nor completely representative of
the population, the capture sample represented fairly evenly those deer
available in open prairies.
Age was determined by tooth eruption and wear (Severinghaus 1949),
but with no previously collected jaws of known age from the Everglades,
accurate aging was only possible after the death of many deer: Jaws were
retained for laboratory analysis. Some deer near the park were shot to
obtain samples for assessment of physiological condition. These data are
compiled in reports to FGFC (see Forrester 1990, 1993b; McCowan 1988).
Radio-tagged deer were located by telemetry on a rotating diel
schedule that allowed one to three locations/animal/week, evenly spaced to
cover 24 hours. A subset of the sample was located more intensively for
150 BULLETIN FLORIDA FLORIDA MUSEUM NATURAL HISTORY VOL. 39(4)
the "fawning ecology study" (Hunter 1990). That study, conducted from
January through July of 1989, included the creation of a digital map of 106
microhabitat types over the Taylor Slough portion of the Park. This map
included water coverage, with the extent of surface water determined by
flying systematic transects and noting the sun reflecting from the water and
by walking to newly flooded zones and measuring water depths. This
information was used for analysis of behavior and habitat use by does
during the fawning season (Hunter 1990).
Telemetry and Mapping of Locations
Collared animals were located by either fixed-wing aircraft or a van.
The plane (Cessna 182) had two H-element antennae, one mounted below
on each wing strut. Antenna were connected to a receiver through a switch-
box which allowed signal reception to be checked on either side of the plane
as the pilot was instructed to home-in on the deer sought. The van was
equipped with an 2.4-m telescoping mast supporting two H-element
antennae set at the same height but 1.5 m apart. This mast could rotate
3600 on a marked compass rose, and the two antennae were connected by a
null combiner, yielding a silent spot thus indicating best direction of signal
(Cochran 1980). When fully extended the antenna reached 29 ft above the
ground. Signals were clear up to 4 km from the target animals in this flat,
open terrain.
Aerial locations were logged on an orthophoto map of the site to a
recognizable hectare square by circling over the animal until landmarks
were recognized. Hence, this technique could only be used during daylight
hours. From dusk through dawn, locations were made from the van by
triangulation using two fixes on the same animal made within a 30-minute
span, or a shorter period if the animal was moving. Approximately 60% of
all locations were evenly represented throughout the diel and seasonal
cycles. The maps used for the population study were USGS orthophoto
maps on 7.5 minute quad sheets at a scale of 1:24,000, drawn in 1972 from
aerial photos. The fawning ecology study (Hunter 1990) used a detailed
microhabitat map created from 1986 aerial photos and digitized on the
Geographical Information System (GIS) to allow more detailed habitat
studies. The maps used for analysis of habitat use thus far include Florida
Game and Fish's 16-habitat map of Dade County, a 5-habitat broad scale
map created by the GIS lab at ENP, and a 176-microhabitat patch map of
Taylor Slough.
SMITH ET AL.: WHITE-TAILED DEER IN ENP
The program TELEM88 (Coleman and Jones 1988) was used to
delineate minimum convex polygons of deer home-range use. These
polygons were digitized for some study animals and overlaid on the various
vegetation maps, on which we had already quantified "availability" of
various habitats by area. "Use" was then compared to random and to
available proportions.
Questions relating to deer habitat use were: What are the major
habitats preferred by each age/sex group? Do deer utilize all habitats in
proportion to their availability? Do adult females change habitat use at
time of fawning for fawn-rearing? Do deer avoid or respond to rising
floodwaters: To what degree do deer and panther home ranges overlap?
What effects do fires have on deer, during and in the successional stages
following a fire? Do human land use practices affect deer? Can
management affect mortality factors of deer?
Other data collected during telemetric locations were activity, habitat,
and, if possible, associations with other deer (visual or simultaneous
reception). Each radio collar was equipped with an activity switch, which
was sensitive to movement of the collar, and activity or inactivity was
expressed by different signal pulse rates. Inactivity was triggered by the
collar being immobile for 60 seconds, and any motion of the head would
switch it back to the "active" phase. Signals were monitored for at least
three minutes per fix. If the animal was recorded as inactive for this entire
period, it was checked again several hours later. If an inactive signal was
obtained two or three times over a 24-hour period, the animal was assumed
to be dead or the collar had fallen off, and a walk-in was performed (defined
below). All visual locations of deer included a description of behavioral
activities and any associations, with great attempts to minimize or prevent
disturbance to the animals. For example, although most deer became
accustomed to the fixed-wing plane, they would sometimes look up at it,
thus triggering an active signal even though they were lying down or
resting. If this was seen the animal was recorded as inactive. Most activity
readings were obtained before the plane was within a mile of the animal,
presumably before it would respond to the presence of the plane.
Population Censusing
Walk-ins were actual locating of an animal by the investigator on foot.
As mentioned above, this was routinely done if the animal was believed to
be dead, or in some cases, for visual observation of doe and fawn behavior.
152 BULLETIN FLORIDA FLORIDA MUSEUM NATURAL HISTORY VOL. 39(4
Doe and fawn associations were recorded most often from three observation
towers placed in the home ranges of does (Hunter 1990). If a carcass was
found, the cause of death was assessed, and if possible, the lower jaw was
retrieved for aging. Simultaneously, kills made by collared panthers were
examined after the cat left and some jaws of uncollared deer were obtained
in this way.
Each radio location (fix) was evaluated for accuracy and only those
fixes with <1 ha error polygons (Heezen and Tester 1967) were used in the
analyses. Radio-collared deer were located biweekly in a stratified pattern
of locations spaced through the 24 hours and evenly distributed over the
sex/age categories of the sample. In addition, during the fawning seasons of
1988 and 1989, one of us (Hunter) located a subsample of pregnant females
an additional 2-3 times per week to obtain an estimate of the fawning date.
Aerial censuses of the 425 km2 study area were flown systematically
approximately every other month, and two observers counted all marked
and unmarked deer seen along the flight path.
RESULTS AND COMPARISONS
Sample Size
Table 1 summarizes the captures and recaptures conducted each year.
Capture-related mortality was very low. The percent of all deer handled
that received injuries or died within three weeks of capture was 6 percent in
1988 and 3 percent in 1989 and 1990.
Sex and Age Structure of Population
As described in Methods, efforts were made to obtain a sample
representative of the population as it exists in the prairies of southeastern
ENP (Table 1). Aging of young deer was usually determined by the tooth
eruption schedule of Severinghaus (1949), whose sample was from central
Florida. The assumption that eruption would be the same in the Everglades
deer was not entirely true. In Severinghaus' study, the permanent third
lower premolar was completely erupted by 20 months, while in ENP many
yearlings known to be older than this retained the juvenile condition of a
deciduous lower premolar. Eruption was not complete in 63% of capture
SMITH ET AL.: WHITE-TAILED DEER IN ENP
Table 1. Captures by netgun of deer in eastern Everglades National Park.
Captures Recaptures Monitored
M FM M FM M FM
1987-1989
F 11 11 1 1 1 1
J 2 3 1 6 3 6
A 13 24 4 3 8 16
1989-1990
F 7 2 1 1 4 4
J 0 0 3 2 3 4
A 1 1 4 17 8 18
M = male; FM = female; F = < 1 yr, J = 1-2 yrs; A = 3+yrs.
animals 18-25 months of age, yet was complete in at least one 24-month
old, thus determination of 2-year-old status was not absolute using this
tooth-eruption method. We could not rely on tooth wear to accurately age
adults; it seems likely that the diet of deer in the Everglades is unique, and
the wear characteristics for each year are unrecorded. We began a
collection of known-age jaws to allow for this comparison in the future.
The most precise method of aging dead deer was from cementum annuli
counts. Of 64 jaws aged accurately by cementum annuli, the following age
groups were obtained. This sample was from collared animals and other
carcasses in the park. The ages identified are included in Table 2.
The pregnancy rate was determined by two methods, with slightly
different results. By visual examination of females from the air and at
capture, no fawns or yearlings appeared pregnant, and only 25 percent of
all yearling females were seen with fawns. However, a physiological
examination of does (Forrester 1990, 1992b) from a sample collected
slightly to the north of ENP showed that 3 out of 3 yearlings were pregnant
154 BULLETIN FLORIDA FLORIDA MUSEUM NATURAL HISTORY VOL. 39(4)
Table 2. Age classes identified.
Years
Year 0-1 2-4 3-5 5-9 9-14 14+
1987-91 15 23 7 11 7 5
when killed, and from a sample of does greater than 2 years of age, 50%
and 79% of those collected in 1988 and 1989, respectively, were pregnant
when killed. This sample provides a minimum estimate of reproduction,
because some of the does were killed in October, during the rut, negating
the possibility of their fertilization just before or after the harvest.
Other estimated ages of live-captured animals indicated a stable age
distribution throughout the period of this study.
While physical size was not used to determine age, it was recorded
with an estimate of age and analyzed to assess the hypothesis that
Everglades deer are smaller than northern deer. Based on captured animals,
fawns weighed from 4 to 25 kg, yearlings from 24 to 34 kg, adult bucks
from 38 to 61 kg, and adult does from 26 to 43 kg. Other measurements
taken on captured animals are summarized in Table 3.
In the eastern ENP, for each year the percentages of collared and
monitored "adult" females observed with a live fawn were: 1987, 67% (but
observation not through full fawning season--82% pregnancy detected);
1988, 86% (94% pregnancy detected); 1989, 94% (87% pregnancy
detected); and 1990 (91% pregnancy detected). None of the harvested
females carried twin fetuses, and only one sighting of a doe with twins
occurred during the entire study. Hence, twinning in the ENP appears to be
extremely rare, with survival of both young even rarer, thus gross
productivity is equal to the pregnancy rate, which we estimate to be about
90% for females 2 3 years and about 80% for 2-year-old females.
A fat estimate was taken on each animal handled using a scale of 1 (no
fat) to 6 (thick fat) by palpitating just above the base of the tail. Adult
SMITH ET AL.: WHITE-TAILED DEER IN ENP
Table 3. Physical characteristics of deer captured in eastern Everglades National Park
during 1989.
Weight' Total length2 Girth Hind foot'
SexAge N X Range X Range X Range X Range
F _2 23' 34.9 26-43 159.7 145-171 74.2 64-80 42.7 39-45
M 2 5 49.3 38-61 174.1 167-181 83.2 75-92 45.4 45-47
F 1 3' 26.3 25-30 149.3 143-153 67.3 62-71 40.8 41-42
M 1 3 30.8 29-34 155.3 150-161 71.0 67-76 43.3 43-45
1 kilograms
2 total length, cm
3 length, cm
4 includes 4 deer collected in health study by Don Forrester
5 included 1 deer collected in health study by Don Forrester
males changed from a pre-rut mean fat index of 5 to a post-rut mean of 2.3.
Lactation had a similar effect on females, changing their pre-lactation (late
pregnancy) mean of 4 to a post-fawning mean of 1.3. This subjective index
is based on a small sample and it has limitations, but it does indicate a
seasonal loss of condition for both sexes, and a recuperation period
sufficient to enter the following breeding season in restored physical
condition.
Estimates of Population Size
Census flights along systematic serpentine transects were flown
approximately every other month, with two observers counting marked and
unmarked animals visible below and to the sides of the plane. This
technique yielded such highly variable results that no reliable density
estimate was obtained until the standard deviation of mean estimates shrank
to a reasonable level as the number of censuses increased. The mean
estimate of density over the 425 km2 study area by December 1990 was
0.67 0.24 deer/km2 (Table 4). While we cannot completely explain the
156 BULLETIN FLORIDA FLORIDA MUSEUM NATURAL HISTORY VOL. 39(4)
Table 4. Population characteristics estimated each year in eastern Everglades National
Park (also see Table 6).
1987 1988 1989 1990
N 35 35-40 -
M-A x 0.14 -
M-J x 0.60 -
M-F 0.67 0.36 -
FR 0.78 0.80 0.71 1.0 (burned)
0.9 (unburned)
M:F 3:1 3.4:1 1:1
PopEst x 230 298 -
Density/km' <1.0 0.55 0.67 0.68
N = number collared deer monitored for most of that year
M-A = adult mortality recorded among collared animals
M-F = fawn mortality recorded among collared or visually known fawns
M-J = juvenile mortality recorded among collared 1-2 year olds
FR = rate of fawning in does > 2 years old and assuming no twinning
M:F = sex ratio of observed adults averaged over year
PopEst = estimate of total number of deer resident in the study area, 425 km2
x = not estimated
variation found between surveys, some of it may be due to seasonal
movements of males (see reproduction), and the overall estimate is
comparable to those of previous authors (Loveless 1959; Schemnitz 1974).
Mortality and Predation
Assessment of All Mortality Factors
Ectoparasite loads were minor to non-existent on ENP deer. For
example, only 4 of 44 deer captured in 1989 were found with detectable
ticks or mites, and these were low loads in September-November. A
veterinary survey of a random sample of deer from ENP and Big Cypress
National Park (BCNP) showed the populations to be in good health with
low parasite loads (McCowan 1990; Forrester 1992b). Parasites are not
believed to be a significant detriment to deer in ENP.
SMITH ET AL.: WHITE-TAILED DEER IN ENP
Age-related Mortality
Fawn mortality was significantly higher in wet prairies than in dry
prairies (Chi2 < 0.01) (Hunter 1990); and it was greater in male fawns than
in females (Smith 1991b). While not all causes of fawn mortality could be
determined, the possible differences between the two prairie types are
unlikely to derive from different predator pressure. More likely the
mortality differences are related to vegetative/phenological differences in the
maternal treatment of male vs female fawns, if (for example) the female
offers more maternal protection to female offspring. The annual mortality
rate of yearlings was approximately 28%. For 2- to 3-year olds the rate
was approximately 16%, and for adults, 4-years old and greater, it was
about 22% per year. Rates were not significantly different according to sex
or age class, except for fawns as noted above.
A Leslie matrix analysis based on the estimated mortality rates
indicates that at least 60 percent survivorship (to adult reproduction) of
female fawns is necessary to maintain numbers of females in the population,
and hence provide stability. Survivorship of fawns into the "follower
stage," at about three months, is not uniform by sex or location: fawns of
both sexes died during this period in wet prairies (Hunter 1990). However,
survivorship of female fawns appears sufficient to allow population growth.
Observed population growth during the five years of study was lower than
the mortality data would predict. There is some (inconclusive) evidence
that a skewed sex ratio at birth may exist in the Everglades population,
favoring males.
Panther Predation and Comments on the Bobcat
The summaries in Table 5 indicate that adult deer are the primary prey
of resident panthers in South Florida, especially in ENP where hogs, the
other prey capable of sustaining adult panthers (Maehr et al. 1990; Alvarez
1993), are almost never found. Panther predation may be a significant
factor on deer populations where deer are hunted (Dalrymple and Bass in
press; Smith and Bass 1994). Where deer are hunted, e.g. BCNP, younger
deer are killed more frequently and bobcat predation on fawns seems to be
an important population factor (Boulay 1992; Sargent 1992). It should be
noted that panthers will kill bobcats, and where panthers are present, bobcat
numbers may be depressed.
158 BULLETIN FLORIDA FLORIDA MUSEUM NATURAL HISTORY VOL. 39(4)
Table 5. Predation of deer by collared panthers in Everglades National Park and vicinity.
No. panthers No. adult study No. study
monitored deer killed fawns
killed
1987 6 0 0*
1988 7 4 1
1989 7 6 1?
1990 8 9 4
* incomplete year
The panther population utilizing ENP remained small throughout the
study, but was thought to be at or near carrying capacity for the region
(Smith and Bass 1994). During the wet season, panthers reduced the area
in which they hunted and killed less deer from May through September
(Dalrymple and Bass in press). Deer comprised 57 percent of 99 identified
kills and 78 percent of the biomass killed by panthers in ENP 1987-1990
(Dalrymple and Bass in press). Adult bucks with a mean age of 5.5 years
were the dominant age/sex class killed (47% of all deer killed).
Although mortality rates varied from year to year, especially among
young fawns, the overall rate of recruitment and mortality were consistently
low compared to other deer populations in South Florida. This implies that
the population is stable. Perhaps the low densities of deer and panthers
reflects limitation by environmental carrying capacity and by density
dependent factors.
In a larger sample of fawns in the Everglades/Big Cypress border
region, mortality was similar among sexes. Male fawns had a greater
survival rate in only one of three years. Fawn survival rate was higher in
BCNP than in ENP (0.39 vs 0.10). Deaths were of higher frequency
between two and six months of age. Bobcat (Lynx rufus) predation
accounted for 58 percent of all deaths. Recruitment ranged from 11% to
26% in BCNP and 0-13% in ENP (Boulay 1992). Overall fawn
survivorship in that study averaged 24%, and loss was attributed mainly to
bobcat predation. The situation is not completely comparable to the
SMITH ET AL.: WHITE-TAILED DEER IN ENP
southeastern ENP, where panther predation exerts a greater impact, but the
biology of deer reproduction should be similar.
Reproduction
Males associated with females from July to October and with each
other in sporadic small groups the rest of the year. Males showed antler
velvet from March to mid-June and shed antlers in December and January.
Fawns were dropped from January through early May, with peaks in
February and March, the late dry season (Hunter 1990). Females seem to
associate in permanent matriarchal groups, although two does maintained
solitary home ranges throughout the study.
The overall pregnancy rate among females 2 2 years old at fawning
was 79 percent. This is a very conservative estimate, as we were unable to
verify fawning until the fawn was visible, which precludes any estimates of
early neonatal mortality. We can conclude that the females in ENP have a
high conception rate and sufficient males are available for mating. Yearling
does do not often seem to conceive. This could result from the sedentary,
matriarchal social system precluding the youngest females from breeding
access to males.
No twinning was observed in the study. Although only six does were
killed and examined for fetuses (Forrester 1992b), the careful monitoring of
a total of 22 does during the fawning season allows us to conclude that
twinning is very rare in the ENP, or if twinning does occur, the mothers are
unable to maintain two fawns, and one sibling usually dies soon after birth.
Fawning proved to be synchronized with the late dry season (Fig. 3)
(Hunter 1990; Boulay 1992) and was significantly later in does resident in
wet prairies vs those resident in dry prairies (Hunter 1990) (Fig. 4). This
was contrary to hypothesized differences in timing, where in wet prairies
fawn mortality due to high-water conditions might possibly constrain
reproductive success and thereby select for earlier fawning. Instead,
although there was significantly more fawn mortality in wet than in dry
prairies, fawning must occur later in wet prairies due to nutritional
constraints on does (Hunter 1990) (see also Fig. 5).
160 BULLETIN FLORIDA FLORIDA MUSEUM NATURAL HISTORY VOL. 39(4)
O.v.seminolus
cm. rain
proportion fawns born
JFMAMJJASONDJFMAMJJASONDJFMAMJJA
I1987 I 1988 I 1989 I
Rain I Fawning I Mean Conception Date
wet & dry prairies combined
Figure 3. Fawning seasons in relation to rainfall averaged over the study site, Taylor
Slough region of Everglades National Park. Deer conceptions (by backdating from
fawning dates) occurred just before the peak of two very different rainy seasons (Hunter
1990).
# fawns born
JanA Jan B Feb A FebB MarA MarB AprA AprB
half-months
S Dry Prairie (n-9) Wet Prairie (n-9)
Figure 4. Number of fawns born in the two prairies types, 1988-1989, Taylor Slough portion of
Everglades National Park. Each block represents fawning events with median date in either the first 15
days of the month (A) or the rest of the month (B). The mean birthdate was significantly different between
the two prairies types (Hunter 1990).
SMITH ET AL.: WHITE-TAILED DEER IN ENP
--DRY PRAIRIE -- WET PRAIRIE
S30
S20-
10
0
JFMAMJJASONDJFMAMJJASONDJFMAMJ JA
1987 I 1988 I 1989
Figure 5. Rainfall on Taylor Slough's dry prairies (station R3110) and wet prairies
(station NP67) during this fawning study, Everglades National Park (Hunter 1990).
Home Range and Habitat Use--Results and Discussion
A serious constraint on the analyses of habitat use was the lack of
digital data on habitat availability. Although the park has a history of
extensive botanical work, and most of the area's flora are quite complete,
the quantification of coverage by each community could be assessed
accurately over such a large area only with the advent of digital remote
sensing data. ENP purchased in 1986 (available in 1987) a complete set of
false color-infrared tinted stereoscopic photographs of the entire
landholding. An initiation of digitizing and ground-truthing the habitat
information from a 10,000-scale resource provided the Taylor Slough
Microhabitat map (Hunter 1990). This map was used for a find-scale (106
microhabitat patch-types, 625 m2 cells) analysis of females' behavior
during the fawning season. The Florida Game and Fresh Water Fish
Commission meanwhile created a broad-scale habitat map (16 categories,
162 BULLETIN FLORIDA FLORIDA MUSEUM NATURAL HISTORY VOL. 39(4)
Table 6. Population characteristics for white-tailed deer in eastern Everglades National
Park for the interval January 1987-June 1991 (3 years).*
Average or RangeJan 87-Jun 91
Density (#/km2) 0.68
Productivity (F/AF) 0.82-0.94
Sex ratio
at birth 1:0.7
at 1 yr or over 1:2.4
Litter size (n = 85) 1.0
Age structure (%)
0-1 yr 22
2-3 yrs 33
4-5 yrs 10
< 6 yrs 33
Mortality
Fawns 0.54
Yearlings 0.24-0.32
Adults (>2 yrs)
Females 0.13
Males 0.19
Recruitment per year (%)
(>18 mon <3 yrs) 1
* Based in part on 35-40 collared deer monitored per year as well as observations of known-age deer.
1000 m2 cells) for the entire state, which was not completely ground-
truthed. The inaccuracies were corrected by Hunter after ground-truthing
the previous map. The broad-scale map was used for a study of
the annual home ranges of males and females in the core study area,
centered around Long Pine Key (LPK). Also, some satellite imagery was
obtained from the Florida Department of Transportation and classified into
six broad landscape types for panther home-range analysis (Smith and Bass
1994).
Home-range size estimates for deer were calculated from telemetry
locations using the program TELEM88 (Coleman and Jones 1988), and the
core activity area was defined as the 80 percent isopleth. Panthers home
SMITH ET AL.: WHITE-TAILED DEER IN ENP
ranges for were estimated from telemetry locations by using the program
HOMERANGE (Samuel et al. 1985); the core activity area was defined as
the 60 percent harmonic mean.
Home ranges of adult male deer were larger than those of adult
females. Overlapping home ranges for 22 females covered 8.15 km2, for an
average individual area of 37 ha. However, taking overlap into
consideration, average core home-range area (80% isopleth) for females
was 430 ha. Home ranges (which barely overlapped) around the LPK area
for 16 adult males covered 18.05 km2, for an average individual area of
1.13 km2 (113 ha). Individual core areas for males averaged 12.4 km2
(1240 ha). Thus, the density of females was nearly four times higher in
these prairies than that of males, and they utilized more of the same habitats
and even ranges than males did. Females showed strong home range fidelity
throughout the study, exhibiting a matriarchal hierarchy of social
dominance with overlapping home ranges of related females. This pattern
also was seen in the BCNP deer populations (Zultowsky 1992). Zultowsky
(1992) found female home ranges averaging 5.4 km2 in BCNP and 2.95 km2
in ENP. Again water levels did not restrict movement, but home ranges
expanded during the dry season. Sargent (1992) found home ranges of
males to be 7.0 km2 in BCNP and 2.9 km2 in ENP.
Adult bucks utilized dense cover year round much more than adult
females did. Collared females were rarely found in the large, dense stands
of pinelands, Schinus, or hardwoods, while most males' home ranges
included these stands. All deer seem to avoid the dense Schinus stands
present in the "Hole-in-the-Donut," but the location as well as capture of
deer in any dense tree cover was nearly impossible. Hence, captures
emphasized prairie residents, and initial conclusions that deer densities were
inversely proportional to distance from LPK or any large tree island (Smith
and Bass 1994) were compromised. Panthers and adult bucks did utilize
the edges of tree islands more than any other habitat (Smith and Bass
1994). This "edge effect" probably reflects a stronger need by males for
flight cover. Many does were resident year-round in open prairies with little
tree cover available. Wet season flooding did not result in any noticeable
shifts in home range use of deer (Hunter 1990). However, panther home
ranges were smaller in the wet season (Dalrymple and Bass in press), and
the cats avoided flooded areas, thus the increased fawn mortality in wet
prairies during the wet season cannot be explained by panther predation.
The severe drought of 1989 allowed the normal lightning strike-
induced fires to burn more widely than usual, and about half the study area
164 BULLETIN FLORIDA FLORIDA MUSEUM NATURAL HISTORY VOL. 39(4)
was burned in the "Ingraham Fire," which was a spectacle second only to
the Yellowstone blaze in recent NPS history. But since a policy of
controlled and natural burns had been maintained for many years preceding
the fire, it mainly cleared undergrowth and did not often kill mature trees.
The prairie vegetation showed regrowth with in a week, while the hardwood
hammocks and some pine lands took months to "green up" (ENP Fire
Management pers. comm.). Following the fire, deer that were resident in
the area did not deviate from normal patterns of home range use. The
natural periodic cycles of fire and flood have been (and still are) believed to
keep the vegetative communities of the Everglades at equilibrium over time
(Robertson 1953; Wade et al. 1980). The noted changes are attributed to
human influences on the wetland ecosystem (Walters et al. 1992). In the
year following the Ingraham Fire, deer were monitored inside and outside of
the burned zone. There was no notable migration of deer into or out of the
burned area at any time. Nor was there any notable change in home range
use during rising waters or when home ranges were 100 percent inundated
(as in the wet year of 1988) (Hunter 1990). However, historical maximum
depths were not reached, so a critical depth where water begins to affect
deer mobility was not determined. Harlow's (1959) suggestion that 30 cm
was the critical depth might be valid, but these depths rarely occur south of
the Water Conservation Areas (40 years ENP hydrology data) (Fig. 6).
The microhabitat study (Hunter 1990) analyzed only the fawning
females' use of 106 microhabitat patch types in wet and dry prairies,
determining their use versus availability. A principle-components analysis
is underway, indicating so far that shelter elements within the prairies, such
as tall grass and willow heads and other shrubbery, are important to does
with fawns. Also, the evidence supports the theory of Loveless (1959) and
Harlow (1961) that "lilies" (four species of aquatic herbs with flowers) are
important to the diets of deer, especially in wet prairies.
While investigating the relative rates of success in fawn-rearing in the
two types of prairie (wet or dry, defined above) (Hunter 1990; 1994), it was
discovered that does residing year-round in wet prairies had significantly
less success raising fawns to the 3-month-old follower stage, and that they
fawned on average one month later than those does living in the dry prairies.
These results suggested a possible nutritional dependency on the part of the
mothers during the early wet season, constraining successful lactation to
that period when blooming of nutritious flowers occurs.
Miller (1993) contrasted home ranges of males and females with
respect to habitat type. In his thesis he distinguished two habitat categories:
SMITH ET AL.: WHITE-TAILED DEER IN ENP
30
eo-
80
30
A A
60
e7 o8 69 70 71 72 73 74 75 78 77
30-0
30-
77 78 79 80 81 82 83 84 85 80 8
years
Figure 6. Modelled water table in relation to ground level (horizontal line at 0), from data
recorded each year from 1957 through 1987, in typical wet prairie (station P38),
Everglades National Park. Year marks are at January (Hunter 1990).
(1) ridges with trees, and (2) wet prairies with scattered trees. Both males
and females had smaller home ranges on ridges (5.3 km2 and 2.5 km2) and
larger home ranges if inhabiting prairies (8.2 and 6.2 ). The ridges are
characterized by greater cover density and frequency of tree islands in
BCNP (Miller 1993).
166 BULLETIN FLORIDA FLORIDA MUSEUM NATURAL HISTORY VOL. 39(4)
GENERAL DISCUSSION
We found little seasonal variation in density and reproductive output of
this relatively K-selected subspecies. Although densities of both deer and
panthers are low in eastern ENP compared to ranges farther north, we
suspect that they are normal and near carrying capacity. The home ranges
and stable, matriarchal social system exhibited by the deer indicate that the
Everglades provides a meta-stable environment. Although primary
production is low, there is a seasonal peak as the floodwaters arrive, which
appears to be the factor influencing the onset of deer reproduction and
ultimately the successful rearing of fawns. Hence, reproduction is
synchronized, and mortality, although exhibiting seasonal fluxes, probably
is important, perhaps regulating the juvenile age class number.
Harlow (1961) conducted a thorough analysis of the nutrients available
to deer over most of Florida. In the Everglades, he quantified the nutrient
content of the 41 food items found in deer rumens, but unfortunately did not
assess availability. Although concentrations of minerals and inorganic ions
are generally lower in Taylor Slough than in the larger Shark River Slough
to the northwest (Schomer and Drew 1982), they were believed to be
sufficient in soil and plant matter such that minerals were not the limiting
factor to deer (Harlow 1961). Instead, the lack of cover and of edible
browse were believed to be limiting, at least in the wet prairies (Harlow and
Jones 1965). Camp (1932) reported that cows could not survive in wet
prairies of South Florida during flooded months, but their larger body size
(and energetic advantage) allows them to obtain a nutritionally better diet
than that on which deer can survive in the same habitat. Comparing deer
diets in the Everglades to those in the rest of Florida, Harlow and Jones
(1965) claimed the prairies to be the habitat least able to support high
densities of deer. The current study showed that deer can and do survive
solely in prairie habitats at low densities and in good health. Densities
found in this study were very comparable to those of white-tailed deer in the
Venezuelan llanos (Brokx 1972) (optimum 4/ km2 = 25 ha/deer; crude
density 2.0-2.5/km2), a similar habitat, implying this is the carrying
capacity of flooded savannahs (Eisenberg et al. 1979; Stuwe 1985).
Authors have labelled bottomland hardwood forests as the best habitat for
deer in the southeastern United States (Sigler-Eisenberg and Eisenberg
1985), but the hardwood forests in the Everglades are scattered fragments
utilized for cover and browse, especially by bucks, and do not characterize
the terrain in terms of dominance. It is possible that the hardwood tree
SMITH ET AL.: WHITE-TAILED DEER IN ENP
islands are the "best" habitat for deer and are monopolized by the adult
males, as has been noted in more crowded deer populations at other locales
(LaGory et al. 1991). But it is unlikely that at these low densities, deer of
either sex in ENP would be excluded from any habitats by density-
dependent factors. Perhaps the more solitary social system of the males
promotes utilization of tree cover, while the more grouped females need
open habitats to promote cohesion.
The vegetative cover consists of structural characteristics of grasslands
as well as interspersion of shrubs and trees, higher interspersion providing
better habitat for deer (Moore and Haas 1973). It seems likely that there is
sufficient cover for female deer and fawns in the prairies with minimal tree
island stands and that the presupposed dependency on tree islands (Loveless
1959; Miller 1992) is not necessarily a selective force shaping behavior of
Everglades deer.
Flooding did not appear to be a direct mortality factor in the typical
Everglades. However, it may be a limiting stress factor in dry prairies,
especially to lactating does. This anecdotal evidence supports the theory
(McNab 1963) that animals in xeric regions will have larger home ranges
than their conspecifics in mesic regions, which was supported by
Rautenstrauch and Krausman (1989) with mule deer (0. hemionus crooki).
The difference in apparent carrying capacity of prairies in the wet season,
and the timing of fawning, is apparently not due directly to the hazards of
water, but more to its effects on the vegetation.
Fire management of Everglades habitats did not prove beneficial to
deer. Unlike some northern hardwood forests, which are maintained and
encouraged to regenerate by fire, pine flatwoods with palmetto understories
are affected by fire, and open wet prairies need to be burned more than they
are to hold back hardwood encroachment, but this encroachment might be
beneficial to the deer. A better land management strategy for the sake of
deer and panthers would be to acquire and protect from disturbance land in
areas which, if disturbed, have a potentially high susceptibility to
floodwater or saltwater intrusion. The entire Everglades ecosystem is in a
state of transition due to pollution, water diversions, urban encroachment,
and now Hurricane Andrew. The restoration efforts should utilize the
information presented here on the previous stable status of deer and
panthers as a minimum baseline. While it is possible the Park can only
support 6-8 panthers (the number that has been used since at least the
1960s [Schemnitz 1974]), it should not be assumed that the ecosystem was
168 BULLETIN FLORIDA FLORIDA MUSEUM NATURAL HISTORY VOL. 39(4)
supporting its maximum capacity of deer, and there is good evidence that
deer might have been the factor limiting panthers (Smith and Bass 1994).
NOTE: This publication is an abbreviated version of the project final report submitted to the U.S.N.P. by J.F.E. and
M.E.S. The priority of authorship reflects the actual field efforts and data analyses. The total data set for E.N.P..
developed by T.R. Smith, will be analyzed and submitted for separate publications by Smith and associates.
J.F.E.
LITERATURE CITED AND REFERENCES
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Belden, R. C., W. B. Frankenberger, and S. T. Schwikert. 1988. Panther habitat use in
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Blouch, R. A. 1987. Reproductive seasonality of the white-tailed deer on the Colombian
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