REPRODUCTIVE BEHAVIOR AND PERFORMANCE OF
THE FEMALE FLORIDA WILD TURKEY
LOVETT E. WILLIAMS, JR.
A DISSERTATION SUBMITTED TO THE GRADUATE SCHOOL OF THE
UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE
REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY
UNIVERSITY OF FLORIDA
This study was funded by the Florida Game and Fresh Water Fish
Commission and the Federal Aid in Wildlife Restoration
(Pittman-Robertson) Program. Former Commission Directors A. D.
Aldrich and 0. E. Frye, Jr., and former Wildlife Division Director J.
A. Powell were particularly supportive as were R. M. Brantly, H. E.
Wallace, F. W. Stanberry, A. L. Egbert, and T. H. Logan.
Most of the field work was conducted on Lykes Fisheating Creek
Wildlife Management Area with the support and cooperation of C. P.
Lykes and B. Swendsen of Lykes Bros., Inc. Thanks are due also
Owen-Illinois, Inc., and their tract manager W. Schlitsgus, for the
use of their property on Lochloosa Wildlife Management Area.
H. Webster generously gave his time and expertise in developing
and constructing the electronic equipment used to remotely monitor
turkey nests. B. L. Akey, L. H. Barwick, W. Bess, T. A. Breault, D.
Z. Caudill, N. F. Eichholz, M. J. Fogarty, D. J. Forrester, W. B.
Frankenberger, H. L. Hill, L. T. Hon, R. C. McCracken, B. Morris, S.
Osceola, J. H. Peoples, R. W. Phillips, W. J. Sadinski, Jr., J. S.
Scanders, A. J. Wilson, J. Wilson, L. Zimmerson, and the late H.
Haywood helped collect field data while they were involved in the
project. J. W. Hardy allowed me to use the bioacoustics laboratory at
the Florida State Museum; T. A. Webber assisted me in making the sound
spectrograms. L. D. Harris of the School of Forest Resources and
Conservation provided assistance with some of the mathematical
calculations, and A. G. Hyde of the U.S. Soil Conservation Service
provided information about the soil types on the study areas. D. D.
Wackerly, C. L. Abercrombie, III, and N. R. Fuller provided
statistical advice and assistance. T. F. Crossman of the U.S.
Agriculture Stabilization and Conservation Service assisted in
measuring habitat acreages of the study areas.
Secretaries W. Circy, M. Shawver, and L. S. Sanders were of much
help at the Fisheating Creek Study Area, as were secretaries M. A.
Lansberry, W. Dunbar, and L. L. Davisworth at the Wildlife Research
Laboratory in Gainesville. S. Street and T. Crown typed the
manuscript. The maps and graphs were prepared by M. Moffitt, B.
Harrison, and R. Harrison. W. A. Greer of the Commission, Office of
Informational Services, was helpful in photo processing.
I would like especially to thank my co-workers D. H. Austin and
the late T. E. Peoples, who participated in every aspect of the field
work and who were responsible for the collection of data during my
absence from the study area.
Assistant Professor M. W. Collopy, Professor D. J. Forrester,
Professor J. W. Hardy, and Assistant Professor G. W. Tanner, who
served on my graduate committee in the School of Forest Resources and
Conservation (Institute of Food and Agricultural Sciences) at the
University of Florida, deserve my sincere appreciation. Professor
R. F. Labisky, my Committee Chairman, provided much encouragement,
advice, and assistance during the preparation of this dissertation.
TABLE OF CONTENTS
RESULTS AND DISCUSSION
Egg Covering and Nest Construction
Laying Posture .
Egg Dropping .
Nest Attendance During the Laying
Nest Disturbance by Man
Incubation Behavior .
Nest Attendance During the Incubat
The Incubation Period.
The Imprinting Period.
Time of Nest Departure by Broods
Attendance of Infertile Eggs
Nesting Seasonality .
Nesting Success and Predation
Abstract of Dissertation Presented to the Graduate School
of the University of Florida in Partial Fulfillment of the
Requirements for the Degree of Doctor of Philosophy
REPRODUCTIVE BEHAVIOR AND PERFORMANCE OF
THE FEMALE FLORIDA WILD TURKEY
Lovett E. Williams, Jr.
Chairman: Ronald F. Labisky
Major Department: Forest Resources and Conservation
Two hundred forty-eight nests of 202 radio-telemetered wild
turkeys (Meleagris gallopavo osceola) were monitored in Florida during
the period 1968-1982 to determine nesting phenology and habitats,
clutch size, activity patterns, sensitivity to disturbance, predation,
renesting tendencies, and nesting success.
Nest initiation began when hens laid eggs, usually in mid-day, in
depressions scratched in the soil, and covered them with dry leaves.
Incubation began gradually after the fifth egg was laid; first laid
eggs experienced about 25 hours more incubation than last eggs. The
incubation period was 27 1.3 days. Hatching synchronization seemed
to be poorly developed. Fifty-eight percent of the nests were located
in saw palmetto (Serenoa repens), 31% in cypress (Taxodium distichum)
woods, and 11% in various "other" habitats. Nest predation was
greatest in cypress woods and least in the habitat category "other."
Fifty-seven percent of the hens whose nesting was disrupted
during the laying period renested; only 28% of those disrupted while
incubating renested. Renesting rates were 44% for adults and 22% for
yearlings; nearly one-half chose a different habitat for renesting.
Hatching required more than 1 day. Egg hatchability was 89.2%.
Sixty-eight percent of the broods departed the nest during morning
hours after sunrise.
The earliest clutch was initiated on 6 March and the latest
clutch hatched on 2 July. Yearlings began nesting later in the season
but finished earlier than adults. Adults laid 10.5 (SE = 0.16) eggs
per clutch and yearlings laid ]0.0 (SE = 0.28); the mean was 10.3 (SE
Fifty-one percent of the hens flushed from nests did not return.
Sixty percent of the incubating hens and 38% of the laying hens
returned; 56% of the adult hens returned but only 27% of the yearlings
returned. Thirty-nine percent of the hens flushed from nests in
cypress woods returned, whereas 59% flushed from nests in palmetto
Approximately 55% of the nests were depredated. When renesting
was taken into account, nesting success was 58.7% for nesting hens.
Laying behavior, incubating activities, nest attendance patterns,
hatching vocalizations, defensive behavior, and hatching behavior also
The wild turkey is endemic to North America. The turkeys were
reclassified (American Ornithologists' Union 1982) recently into the
family Phasianidae. The only other living species in the turkey
subfamily Meleagridinae is the ocellated turkey (Meleagris ocellata)
of southern Mexico and Central America.
The Florida subspecies of wild turkey (M. j. osceola) was named
for the Seminole Indian, Osceola, by W. E. D. Scott (1890) from type
specimens taken near Tarpon Springs. It is a clinal subspecies that
intergrades with the eastern form (M. 1. silvestris) in a zone from
southern South Carolina, across southern Georgia, northern Florida,
southern Alabama, southern Mississippi, to eastern Louisiana (Aldrich
and Duvall 1955).
Florida had a sizable turkey population in early historic times
(Wright 1915), but the species was eliminated by unregulated hunting
from some parts of the state by 1948 (Newman and Griffin 1950). In
the statewide restocking program that was initiated in 1951 (Powell
1965), turkeys were trapped from protected Florida populations and
released in suitable range that was not inhabited by turkeys.
Completion of the restocking program in 1970 gave Florida the
distinction of being the first state to complete a successful
statewide turkey restoration program.
Estimates of the fall population in Florida topped 100,000 in
1964. In 1966 the population and harvest plumetted due to unknown
causes, which resulted in considerable concern. By 1969 turkey
populations had recovered to pre-die-off levels, although there was
evidence that populations on certain wildlife management areas were
suffering from over-harvest during fall, either-sex hunting seasons
(Williams et al. 1978).
Curtailment of hen harvest on wildlife management areas, by
termination of fall hunting and expansion of spring gobbler hunting,
was being contemplated. Because there had been no research on turkey
ecology in Florida, effects of spring gobbler hunting on nesting
processes were unknown. Consequently, this study on nesting ecology
was initiated with emphasis on aspects that relate to possible effects
of spring gobbler hunting on reproduction. Specific objectives were
to characterize the seasonality of nesting, identify nesting habitats,
determine activity patterns of nesting hens, measure the sensitivity
of nesting hens to human disturbance, measure renesting tendencies,
and generally elucidate the behavioral characteristics of the hen
during the reproductive period.
Field work was conducted on Lykes Fisheating Creek Wildlife
Management Area (WMA) during 14 of the 15 years from 1968 to 1982 and
on Lochloosa WMA during 1969, 1970, 1973 and 1975. The hunting rights
on both privately owned areas are leased to the Florida Game and Fresh
Water Fish Commission for public hunting.
The Fisheating Creek Study Area (Fig. 1) is located in Glades
County, about 20 km west of Lake Okeechobec. The terrain is flat,
ranging between 9 m and 17 m above mean sea level. Soils are
predominantly sandy. The major soil associations are Fresh Water
Marsh and Swamp along the creek to about 1 km outward, Myakka-Pomello-
Basinger on the higher areas between the creek and palmetto prairie,
and Oldsman-Wabasso-Felda in the palmetto prairie (Florida Department
of Administration 1974).
The climate is subtropical. At Ft. Myers, which is approximately
81 km to the southwest (the nearest reference point for complete
weather data), the mean maximum and minimum daily temperatures in
April are 28.9 C and 16.3 C, respectively. Mean maximum and minimum
daily temperatures in July are 32.8 C and 22.9 C, respectively. Mean
annual temperature at Moore Haven, about 30 km to the southeast, is
22.8 C. The mean date of the first subfreezing temperature at Moore
Haven is December 25 and the mean date of the last winter freeze is
January 23 (National Oceanic and Atmospheric Administration 1978).
Mean annual precipitation at Moore Haven is 127.9 cm, and at LaBelle,
about 25 km to the southwest, 132.5 cm. More than 60% of the annual
precipitation comes from thunder showers during the summer months.
Six plant associations with narrow, ill-defined ecotones between
them, were delineated at Fisheating Creek. Cypress woods, which
comprised 51% of the study area, occurred along the creek (Fig. 2).
The creek was subject to shallow flooding at least once annually.
Understory shrubs and midstory trees, other than young cypress, were
sparse; the ground cover of carpet grass (Axonopus compressus),
smartweed (Polygonum sp.), mistflower (Eupatorium coelestinum) and
other annual herbs became dense by May (Fig. 3).
Live oak trees (Quercus virginiana), which comprised 12% of the
study area, occurred in stands called hammocks (Fig. 4). Most
hammocks contained small clumps of saw palmetto and cabbage palm
(Sabal palmetto). A few hammocks contained laurel oak (Q.
laurifolia), red mulberry (Morus rubra), and hackberry (Celtis
laevigata) also. Trees in the hammocks were draped with Spanish moss
(Tillandsia usneoides) and other epiphytes.
Glades paralleled the cypress woods, forming zones of short
grasses (mainly Axonopus compressus) that were dotted with isolated
live oak trees and small live oak hammocks (Fig. 5). These open areas
were grazed heavily by cattle and had the appearance of semi-improved
pastures. Approximately 17% of the study area was glades.
Broadleaf evergreen shrubs (e.g. Myrica cerifera), evergreen
trees (Gordonia lasianthus, Magnolia virginiana, and Persea spp.), and
vines (Vitis sp. and Smilax spp.) existed in bay heads and swamps
which comprised 2% of the study area.
Figure 2. Aerial view of cypress woods on the Fisheating Creek
Study Area in spring.
Figure 3. Inside the cypress woods at Fisheating Creek Study
Area in May.
Bayheads and swamps often contained surface water and supported dense,
woody, understory vegetation; the soils contained a relatively high
proportion of humus and litter.
Oak scrub, which covered 12% of the area, is an association of
small, mostly evergreen oaks (Q. chapmanii, Q. myrtifolia, Q.
geminata, and Q. inopina) and other short, woody vegetation (e.g.
Lvonia ferruginea, Befaria racemosa, Ilex opaca var. arenicola) on
sandy soils that lie about 13 m above mean sea level (Fig. 6). Sand
pine (Pinus clausa) was not present.
The prairie is a wide, flat expanse of saw palmetto and wire
grass (Aristida stricta), dotted with widely-spaced pine trees (Pinus
palustris and P. elliottii) and small islands of oak scrub. The
prairie extended for many miles to the north and south of the
woodlands along Fisheating Creek and was a travel barrier to turkeys.
It was not considered part of the study area except for the ecotones
between palmetto prairie and other plant associations. This ecotonal
zone was about i-km wide and comprised approximately 5% of the study
Small patches of other plant associations, creeks, ponds,
sloughs, and marshes, improved pastures for cattle, and roads made up
the remaining 1% of the study area. The major plant associations
formed zones approximately parallel to Fisheating Creek (Fig. 7).
The owners ran cattle on the area and feral hogs were present.
No special land management practice for turkeys was used on the area.
Lochloosa WMA is located principally in Alachua County of
northern Florida, about 350 km north of Fisheating Creek WMA. The
Figure 7. Aerial view of a typical cross-section of the Fisheating
Creek Study Area showing cypress woods (top), a glade parallel to
the creek, a live oak hammock adjacent to the glade, saw palmetto
prairie (left middle), and oak scrub (lower middle).
prairie (left middle), and oak scrub (lower middle).
major land owner, Owen-Illinois, Inc. (Forest Products Division),
managed the property primarily for pulpwood. The study was conducted
on a sector that comprised about 3,200 ha of the 12,500 ha WMA (Fig.
The terrain is flat to slightly rolling, ranging 17 m to 30 m
above mean sea level. Soil types on the sand ridges are Millhopper,
Tavares, and Newnan sands. In the ponds and swamps, the main soils
are Monteocha loamy sand, Pomona sand, and Samsula muck, whereas the
main flatwoods soil is Pomona sand (U.S. Department of Agriculture
The mean annual temperature is 22.20 C at Gainesville, 15 km
northwest of the area. The mean date of the first and last frost is
December 6 and February 14, respectively. Mean annual rainfall is
133.2 cm, with more than 50% occurring in summer (National Oceanic and
Atmospheric Administration 1978).
The original upland plant associations were mainly longleaf pine
(Pinus palustris) and turkey oak (Quercus laevis), and slash pine (P.
elliotti) flatwoods (U.S. Department of Agricuture 1980). These
associations were replaced mostly by slash pine plantations during the
1950's. Areas planted were first chopped, burned, and then machine
planted at a density of 764 seedlings per ha. Pine woods comprised
approximately 50% of the area. About 9% of the study area was in
natural slash pine stands. Many of the large live oak hammocks had
been eliminated by commercial forest management practices. A hardwood
control program implemented during the 1950's was not entirely
successful; consequently, the slash pine plantations had nearly as
much young live oak and laurel oak as pine (Fig. 9). The planted pine
and oak association occupied about 15% of the study area.
Pinelands in the study area were logged, primarily by
clearcutting, at various times during the study making it difficult to
meaningfully catagorize the resulting associations and stages of plant
Recently clearcut pinelands covered approximately 7% of the area
and improved cattle pastures, 2%. Cypress heads and hardwood swamps
occupied 10% of the area and open ponds comprised about 1%. Approxi-
mately 2% of the area was in hardwood hammock; seasonally wet prairies
made up the remaining 4%. There were no palmetto flats or grazed
glades, as described for Fisheating Creek, but saw palmetto occurred
abundantly. The area was grazed by cattle; feral hogs occurred in
The wild turkey was eliminated by overhunting in the area that is
now in the Lochloosa WMA between 1900 and 1950. The area was
restocked with wild-trapped birds from Fisheating Creek WMA in the
early 1960's. No other turkey management, except enforcement of
hunting regulations, had been practiced. The area was open to
year-round public use. The spring gobbler season consisted of 16
half-days of hunting in late March during the study period.
- 1( d -
Figure 9. Thirty-year-old planted slash pine woods with oak
regeneration on Lochloosa Study Area, Alachua County, Florida,
Hens were captured with cannon nets (Austin 1965), rocket nets,
orally administered tribromoethanol (Williams et al. 1973), and
alpha-chloralose (Williams 1966). Age classes of the hens were
determined by the configuration of the greater upper secondary coverts
(Williams 1961). All birds were weighed and banded prior to being
radio-instrumented. Turkey handling procedures have been described
previously (Austin et al. 1973).
Radio transmitters were attached to 414 hens, 35 on the Lochloosa
Study Area and 379 on the Fisheating Creek Study Area. Data were
obtained from 248 nests of 202 hens that nested one or more times.
Because of the small number of nests (N = 15) on the Lochloosa Study
Area, no attempt has been made to contrast the turkey populations on
the two study areas.
Transmitters were spaced across the frequency band (150.815 MHz
to 151.210 MHz) to provide 24 channels separated by 10 to 15 KHz.
Transmitters weighed from 65 g to 90 g, measured approximately 50 mm x
25 mm x 80 mm, and met or exceeded the performance requirements of 2-
km range and 6-month signal transmission without battery change.
Transmitters were fitted to the turkeys by underwing loops of
latex surgical tubing (3/32-inch wall, 1/16-inch inside diameter).
One loop was tied under each wing with a square knot or single beckett
bend. Tubing was attached to transmitters with fiberglass tape. The
Table 1. The number of Florida wild turkey hens instrumented and
monitored, Fisheating Creek and Lochloosa study areas, 1968-82.
Found dead Contact lost Monitored
before before during
Number nesting nesting nesting Nests
Year instrumented season season season found
1968 30 0 0 30 20
1969 26 0 4 22 14
1970 34 0 3 31 19
1971 33 5 4 24 14
1972 35 2 6 27 14
1973 30 1 0 29 20
1974 33 1 4 34 25
1975 25 1 2 22 20
1976 20 0 3 17 12
1978 18 0 1 13 12
1979 21 3 1 17 13
1980 43 5 8 30 28
1981 54 9 4 41 32
1982 12 1 3 8 5
Total 414 28 43 345 248
aNot including those found dead.
hens were not noticeably hindered by the transmitter package and those
recaptured showed no evidence of serious chafing.
Field monitoring was accomplished with 24-channel, crystal
controlled, portable radio receivers. Receiving antennas included
1/4-wave whips on trucks, hand-held yagis for work on foot, and large
multi-element directional antennas mounted on trucks. Nests were
found by radio signals when instrumented hens were present. Data were
collected at nests while the hens were absent.
Electronic devices were used to record nest attendance of the
hens. The low-power signal from the transmitter on a hen was
monitored by a battery-powered receiver hidden near the nest. This
signal was re-transmitted to the field station on a different
frequency by a directional antenna; maximum transmission was 8 km. The
sensitivity of the receiver at the nest was adjusted to restrict the
radius of signal reception to within about 1 m, which made the
equipment function as a proximity detector. At headquarters, the
incoming signal activated an electronic switch and was recorded on a
30-day time-calibrated Esterline-Angus event recorder, thereby making
a continuous record of the time the hen was on the nest. A maximum of
20 nests could be monitored simultaneously. Nests were monitored
approximately 8,000 hours by automatic recorders and about 400 hours
manually. Visual observations confirmed the reliability of the nest
Behavior of hens was directly observed with spotting telescopes
and binoculars from portable cloth blinds located about 30 m from the
nests. Microphones were placed within 1 m of seven nests to monitor
and record the sounds of hatching on a 1/4-inch open reel Uher tape
recorder. Sound spectrograms of recorded hen and poult vocalizations
were made on a Sona-Graph model 7029A instrument (Kay Electric
All vegetation within 1.5 m of each of 57 nests found on the
Fisheating Creek Study.Area during the 5 years, 1968-1972, was
identified and its coverage estimated visually to the nearest 5%;
percent coverage of overhead vegetation within 2 m above each nest was
visually estimated. The habitat within 45 m of 236 nests found in the
study was classified by the most abundant vegetation present--
palmetto, cypress woods, or other. Habitat acreages were measured
from aerial photographs (scale 600 feet = 1 inch) with a Model
1211-H-1 Nemonics Corporation electronic digital planimeter.
The Mayfield (1961) method, which utilizers data from nests that
were observed during only part of the laying or incubation period, was
used to calculate nesting success. The Wilcoxon Rank Sum test was
used to compare clutch sizes of first, second, and third nests and of
nests in which incubation began before 1 May, between 1 May and 20
May, and after 20 May. Chi-square analyses were used to test for
differences in renesting tendencies of hens whose nests were disrupted
during the laying vs the incubating periods; differences in the
proportions of nests located in the three habitat types and the
success and predation rates in each habitat type; differences in
predation rates of clutches that hatched before 1 May, between 1 May
and 20 May, and after 20 May; differences in the tendencies of hens to
return to their nests when flushed; differences in return-after-
flushing tendencies of hens nesting in three habitat types; and
differences in the proportion of yearling vs adult hens that abandoned
their nests after being flushed. The t-test procedure was used to
compare renesting rates of adult and yearling hens and mean length of
recesses of incubating hens. The Kolmogorov-Smirnov Z test (Zar 1974)
was used to test for differences in the distribution of seasonal
nesting curves for adult and yearling hens. Fisher's least
significant difference test (SAS Institute Inc. 1982) was used to
compare length of recesses during four segments of the period of
continuous incubating behavior. The confidence interval on the
proportion of recesses hens took in the afternoon followed the form
x t c/2, dfSE(x)
RESULTS AND DISCUSSION
The mating system of the Florida turkey fits Oring's (1982)
description of male-dominance polygyny with intermediate dispersal.
Gobbling and strutting activities by males in early February, before
the hen flocks dissolved, indicated that gobblers were receptive to
mating earlier than hens. Hen flocks dissolved in March prior to the
onset of nesting. Hens, upon attainment of sexual receptivity,
visited the gobblers for mating.
Before nesting, hens established new home ranges and often
roosted alone in small, isolated hammocks and bay-heads where gobblers
and non-nesting hens seldom ventured and rarely roosted (Williams et
al. 1974). Hens frequently were seen traversing the edge of saw
palmetto prairies and the oak scrub-palmetto ecotone as though
searching for nesting sites. Tracking effort was concentrated in
these areas so that nests could be found early in the laying cycle.
Egg Covering and Nest Construction
Four hens were monitored by telemetry as they established their
nests and laid their first eggs. When a hen approached the nesting
area she would spend approximately 5-20 minutes moving in a restricted
area before becoming still. This behavior pattern suggests that she
was in the process of selecting a place for the nest.
The deposition of the first egg followed a definite pattern.
The hens scratched shallow depressions in the soil, laid the egg,
placed a few dried leaves over the egg, and departed. The mean length
of time spent on the nest while laying the first egg was 70 minutes
(N = 4, SE = 28.4). Freshly laid eggs were clean and chalky, with a
thin layer of sand adhering only to the side in contact with the
Five additional nests were found at the time that the second or
third egg was being laid. In two of these nests, shallow
scratched-out depressions were found within 10 m of the nests in what
appeared to be suitable nesting places, indicating that these hens had
scratched shallow depressions in more than one place before selecting
the place they would lay.
Evidently, hens did not transport nesting material to cover their
eggs, but rather used debris present at the site. Two hens observed
while laying covered their eggs with plant debris picked up from
beside their nests; no hen was observed carrying nesting material.
About a century ago, an observer reported to Bendire (1892) that
Florida turkey nests were lined with dead leaves and grass that were
so like the surrounding debris that he wondered whether the material
was placed there by the hen or was already present under the eggs.
Although numerous patches of bare ground were available in the
vicinity of most nests, only a single nest was established on such a
site. The availability of nearby dried plant material may be a factor
in nest site selection.
Twenty nests that were observed a total of 90 times during the
laying period were covered sparsely with dried leaves. Approximately
160 different nests were inspected at least once while the hens were
on recess during the incubating period; none of these nests was
covered. These observations indicate a tendency for hens to cover
their eggs while away during the laying period but to leave them
uncovered while on recess during the incubation period. Although many
writers (e.g., Audubon 1831, McIlhenny 1914, Mosby and Handley 1943,
Bailey et al. 1951) have stated that turkey hens cover their eggs with
leaves, they did not specify that this occurred only during the laying
period. Green (1982) reported that hens in Michigan did not cover
their eggs before taking incubation recesses.
Camouflage, rather than insulation, appears to be the function of
egg covering by the turkey. If insulation were required, it would
be needed also during the incubation period when embryos are more
vulnerable to chilling; however, turkeys do not cover the eggs during
incubation recesses. Furthermore, the fact that hens use only debris
from beside the nest to cover their eggs suggests that the function is
to blend the nest with the immediate surroundings.
Egg covering also is the means by which a turkey nest is
constructed. When the hen returns to the nest to lay each egg, she
does not uncover the nest before laying, which causes more debris to
accumulate with the laying of each egg. When the hen turns the eggs,
the debris settles to the bottom and sides of the nest and by the time
the last egg is laid, the nest depression is well lined with leaves.
A typical nest measures 2 cm deep, 20 cm wide, and 24 cm long
(Williams et al. 1968).
Three hens were observed laying a total of 11 eggs. Hens sat on,
or crouched over, their nests before laying. The laying of the egg
was accomplished from a partially erect body position. They trembled
as they laid, with wings drooped slightly and tails raised. The back
feathers were ventilated. Eggs were laid on the ground beside the
other eggs and not on top of them. Of the more than 2,000 turkey eggs
examined, only two were cracked in a manner that would suggest one egg
had struck another while being laid.
Some bird species, for example the ring-necked pheasant
(Phasianus colchicus), have very large clutches when more than one hen
lays in the same nest. Such multiple nesting has been reported for
the wild turkey (Bent 1932, Mosby and Handley 1943). However, the
only previous evidence of multiple nesting is Bendire's (1892) report
of a turkey hen seen on a nest while another hen was seen standing
close by and presumed to be waiting to lay in the same nest; Audubon
(1831) also mentioned three hens on the same nest.
In the present study, two hens were observed visiting the same
nest on three occasions and both were seen sitting on the nest
although never at the same time. Telemetry data indicated that these
hens did not associate with each other. More than one egg per day was
laid in the nest on two occasions and it seems almost certain that
both hens laid in this nest. The nest was deserted after the twelfth
egg was laid.
Another nest was photographed after the hen had been flushed
deliberately. When the nest was examined about 2 hours later, one egg
had been added. The setting hen had passed the twentieth day of
incubating behavior; therefore, the extra egg must have been laid by
The potential for multiple nesting exists in Florida turkey
populations; however, it is probably not very common. If multiple
nesting depends upon chance encounters, it should be expected to be
more prevalent when nest density is higher, which would partly explain
the much higher incidence of multiple nesting observed in the
ring-necked pheasant (Labisky 1968).
Some birds occasionally lay single eggs where there is no nest.
Stoddard (1931) reported this phenomenon as common in the northern
bobwhite (Colinus virginianus). Single eggs that were never incubated
constituted a minimum of 8% of the annual egg production of
ring-necked pheasants in Illinois (Labisky 1968). In the present
study, only seven turkey eggs not associated with a nest were observed
in approximately 30,000 man-hours of field work during the nesting
season, indicating that egg-dropping is not prevalent among Florida
Nest Attendance During the Laying Period
Blakey (1937:7) provides the only reference about the pattern of
egg laying by the wild turkey by saying "Study of artificially
propagated wild turkey shows that, when . [egg laying] . .
becomes regular, one egg is laid daily, approximately one hour later
each day, beginning at about one hour after sunrise and continuing
until sundown terminates the cycle. Then the hen may skip a day and
begin over again at the early morning hour and repeat the cycle."
In four nests monitored from the deposition of the first egg, the
hens came to lay between 1120 hours and 1300 hours (x = 1234 hours).
In all laying events observed, only 8 of 74 eggs were laid before 1100
hours. Two of the four hens that were monitored from the laying of
the first egg skipped laying the day after laying the first egg; one
of these hens skipped laying also the day after laying the second egg.
The other two hens that were monitored from the laying of the first
egg skipped laying early in the laying period--one skipped the day
after the third egg and the other skipped after laying both the second
and third eggs. In a total of 103 laying events by 22 hens, the only
additional skipped days observed were after the first, fourth, and
ninth eggs. Thus, hens did not exhibit a regular pattern of skipping
a day in laying after the fifth egg of the clutch had been laid.
To test the hypothesis that wild turkeys laid approximately 1
hour later each day, the time of laying of 29 pairs of consecutively
laid eggs was compared. This comparison revealed that 50% were laid
within the same hour as the previous egg, 17% were laid at least 1
hour earlier, and only 24% were laid 1 hour later. Furthermore, in
65% of the laying events monitored, hens came to the nest to lay
between 1000 and 1500 hours. This pattern of laying in mid-day
compares closely with the pattern reported for the domestic turkey
(Stockton and Asmundson 1950) but not with the pattern reported for
wild turkeys by Blakey (1937).
In 74 observations of laying events in 22 nests, only 2 days were
skipped after the fourth egg was laid, and in neither of these cases
was laying resumed in the early morning of the following day. Thus
there was no evidence that early morning laying followed skipped days
late in the laying period.
In summary, the first egg of the Florida turkey is usually laid
in mid-day and is followed by a lapse day; the second egg is laid on
the third day and is sometimes followed by a lapse day. A few hens
skip laying one additional day after the third egg, but very few
lapses occur later in the laying period. The fourth through final
eggs are usually laid on consecutive days with a tendency to lay a few
minutes later and to remain on the nest longer each day. The clutch
is typically completed in late afternoon (Fig. 10). Hens failed to
lay only 4 of 76 times they were observed visiting their nests during
the laying period.
Hens remained on their nests an average of 55 minutes while
laying each of eggs one through five. The apparent decrease (X = -7.3
minutes, SE = 11.3) in mean attendance during the laying of each of
the first five eggs was not significant (P = 0.531) (Fig. 11). Hens
remained on their nests an average of 50 minutes (SE = 12.8) longer as
they laid each of eggs 5 through 12. Hens were remaining on the nest
about 348 minutes with the laying of the eleventh egg. Thus,
incubating behavior began gradually with the laying of the sixth egg
and the length of incubating sessions increased with the laying of
each successive egg. The first egg was subjected to about 25 hours of
incubation, on the average, before the twelfth, or last, egg was laid.
No hen began continuous incubating behavior with fewer than five
eggs. This finding, coupled with the observed tendency of hens to
begin incubating with the laying of the sixth egg, suggested that at
least five eggs are required to stimulate the gradual onset of
incubating behavior. This hypothesis was tested by manipulating eggs
in three nests during the laying period. In one nest, four eggs were
removed from a clutch of seven, and then one egg was removed each day
to maintain the clutch at three eggs. The hen abandoned this nest
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after laying the ninth egg. In another nest, three of six eggs were
removed at the time the nest was found; this clutch also was
maintained as a three-egg clutch. This hen abandoned the nest after
laying 12 eggs without initiating continuous incubating behavior. The
electronic monitor indicated that the hen did not exhibit the normal
pattern of gradually lengthening incubating behavior late in the
laying cycle; she remained at the nest no more than 34 minutes while
laying any egg, thereby demonstrating behavior typical of a hen in the
laying cycle. Another nest was found with four eggs and the clutch
was held at that number by daily removal of eggs during the remainder
of the laying period. This hen abandoned the nest after laying the
ninth egg. The abandonment of the three manipulated clutches supports
the hypothesis that approximately five eggs in the nest are required
to stimulate the gradual onset of incubating behavior.
If the turkey were a so-called "indeterminant" layer (Cole 1917),
these hens would have laid a greater number of eggs than represented
in normal clutches. The result indicates that the wild turkey is a
"determinant" layer and will not continue to lay indefinitely merely
because its eggs are removed as they are laid.
The gradual onset of incubating behavior is stimulated by five
eggs, probably through visual or tactile cues. Termination of laying
occurs several days after the onset of gradual incubation, probably
caused by increasing prolactin secretions as incubating behavior
progresses (Eisner 1958). The daily increase in the secretion of
prolactin would effectively determine the clutch size in the species
by leading to the termination of laying.
A clutch is complete when no additional eggs are laid. Clutch
size averaged 10.3 eggs in 179 complete clutches (Table 2). Clutch
size of yearling hens, which averaged 10.0 differed significantly
(Wilcoxon two-sample test, S = 2248, Z = 1.6245, P = 0.104) from those
of adult hens, which averaged 10.5 eggs. Sixty-seven percent of the
complete clutches had 9, 10, or 11 eggs; the modal clutch size was 10
eggs (Fig. 12). No complete clutch contained fewer than five eggs.
Mean clutch size did not vary significantly among years (F = 1.50, df
= 178, P = 0.12).
The Wilcoxon Rank Sum test indicated that mean clutch size of the
first (x = 10.4, N = 150), second (x = 10.2, N = 26), and third (R =
9.8, N = 4) nests of the same hens within the the same year did not
differ significantly (first vs. second: Z = 0.088, P = 0.93; second
vs. third, Z = 0.751, P = 0.45; first vs. third: Z = 0.836, P =
0.40). Mean clutch size among nests in which incubating behavior
began before 1 May (x = 10.2, N = 99), between 1 May and 20 May (x =
10.0, N = 33), and after 20 May (x = 9.6, N = 8) did not differ
significantly (Kruskal-Wallis X2 = 1.25, df = 2, P = 0.54).
Mean clutch sizes of the wild turkey in other regions of the
United States indicated that clutches in Florida populations may be
smaller than in eastern wild turkey populations in Alabama,
Mississippi, Missouri and Virginia, but larger than those in
populations of the Rio Grande turkey in Texas (Fig. 13). Comparisons
using the Student's t-test indicated no significant difference in mean
clutch sizes between Florida and Mississippi (t = 1.15, df = 189, P >
0.01) or Florida and Texas (t = 0.73, df = 213, P > 0.01). The
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clutch size reported in one of the Virginia studies (McDowell 1956)
was larger than in the present Florida study (t = 2.77, df = 211, P <
0.01). Mean clutch size in the turkey may be under genetic control
and may vary among populations, but the genetic component is
outweighed by the combined effects of experimental error and small
sample size in the data presently available from other regions.
Hens carrying transmitters emitting weak signals and those that
moved away from the study areas were not monitored closely. Some of
these hens probably had their nests destroyed by predators without
the nests being detected in the study. Consequently, the renesting
statistics are minimum estimates.
Nearly fifty-seven percent (56.6%) of 30 hens that had their
nests disrupted during the laying period renested, whereas only 28% of
93 hens renested after their nests were disrupted during the period of
continuous incubating behavior (N = 123, X2 = 8.223, df = 1, P =
0.004) (Fig. 14). No hen renested after incubating longer than 18
days. Adult hens renested with greater frequency than yearlings; 44%
of 80 adults nested at least twice in the same year whereas only 22%
of 23 yearlings renested (t = 2.1, df 1, P < 0.05) (Fig. 14).
Nest Disturbance by Man
Sixty-two percent of 38 hens that were flushed from their nests
during the laying period did not return. Since 43% of 30 hens whose
nests were disrupted did not renest, the loss to the population of
potential reproduction was 0.27 (0.62 x 0.43) nests per hen flushed
during the laying period. During the incubation period, 40% of 38
hens that had been flushed abandoned their nests and 72% (N = 93) of
L S -
them did not renest, representing a loss of approximately 0.29 (0.40 x
0.72) nests per hen flushed. Thus, it would make little difference
whether a hen were flushed during the laying or the incubation period
with respect to the net impact on annual reproduction. Five (2%) of
218 nests were deserted for no apparent reason.
The term "incubation" as commonly used has two meanings, namely
1) the behavior of the hen sitting on or standing over the eggs and 2)
the embryonic developmental processes that take place inside the egg
shell. These components are independent--a hen can carry on
incubating behavior whether or not embryonic development takes place
(as with infertile or artificial eggs) and the embryo can develop
without a parent incubating it (as in artificial or natural
incubators). When the term incubation is applied to the behavior of
the hen, it involves a presumption that embryonic development is
occurring in the eggs, which may not be the case. Therefore, the
sitting of the hen would better be called "incubating behavior" to
distinguish it from the incubation process that occurs within the egg-
shell. In the Florida turkey, incubating behavior consists of
gradually lengthening afternoon incubating sessions after the fifth
egg is laid, followed by continuous day and night incubating sessions
upon completion of the clutch.
Twenty-four hens began incubating overnight on either the day
before laying the final egg, the same day of laying the final egg, or
the day after laying the final egg (Fig. 15). Two eggs were laid in
4 of the 24 nests after continuous incubating behavior began. Of
these eight additional eggs, only one was left unhatched despite
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the fact that the last laid egg in each nest had been incubated at
least 2 days less than the rest of the clutch.
Stoddard (1931) stated that the northern bobwhite leaves its eggs
unincubated for as long as 1 week after the last egg is laid. No
turkey clutch went unincubated for as long as a whole day after the
last egg was laid. This behavioral trait of the turkey would minimize
the risk of nest predation by lessening the time the nest is exposed
Approximately 400 man-hours were spent observing nine different
hens on their nests during continuous incubating behavior. While
sitting, the hens' body parts were positioned as in standing except
that their legs were folded at the upper tarsal joints forward under
the breast. While sleeping in the nest during daylight hours, the
head and neck were drawn in, the eyes were closed, and the wings
drooped along the sides.
When turning eggs, hens crouched by flexing the intertarsal
joints; they did not stand erect. Several eggs were usually
rearranged with a single motion of the head but the activity seemed to
be directed at only a single egg at a time. The motion of the head
not only turned the eggs, but also repositioned them in the nest so
that no egg remained in the same part of the nest for more than a few
hours at a time. Hens often arose and gazed down at their eggs for a
few seconds, and sometimes settled back without turning them. They
usually gazed intently before turning an egg--the gazing behavior
seemed to involve some cue that led to egg turning.
While standing in the nest, the bird's body posture was the same
as when it stood at other times. Hens settled back on the nest after
standing or crouching by moving the body forward with an upward
swinging motion that placed some of the breast feathers over the eggs
in front of the hen, thereby covering all the eggs.
As air temperatures increased during late morning, incubating
hens began to pant, with partly open bills, and sometimes ventilated
back feathers. Panting became faster, with the bill opened wider, as
mid-day temperatures increased. The sequence was reversed as
temperatures decreased in the afternoon. Hens would move their heads
or change positions to avoid spots of direct sunlight that penetrated
the overhead vegetation.
Two incubating hens retrieved single eggs that had rolled from
their nests; however, the retrival process was not observed. Two hens
deserted their nests when most of their eggs had been rolled out
intact by the rooting of armadillos. One hen continued to incubate a
clutch containing one broken egg; 12 hens deserted nests that
contained one or two broken eggs. It could not be determined whether
desertion was due to the presence of the broken eggs or to the
disturbance that caused the eggs to be broken.
Nest Attendance During the Incubation Period
Incubating hens recessed for 98 minutes at a mean interval of 1.9
days (Table 3). Four monitored hens remained continuously on their
nests for 3 days; the longest period of uninterrupted sitting was 4
days. A few hens recessed twice each day on several days. The period
of nest attendance immediately preceding hatching averaged 2.4 days (N
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There was a tendency for a given hen to recess in morning or
afternoon on several consecutive days (Table 4). Consecutive daily
recesses were during the same morning, noon, or afternoon period 32
times and during a different period 30 times. None of the five hens
observed completed the-entire incubation period without changing
recess patterns from morning or noon to afternoon, or vice versa, at
least once. Thus hens do not recess at the same time of day
throughout the duration of the incubating activity.
Thirty-nine percent of 67 recesses by five hens began before noon
and 61% began after noon (Table 4), indicating a tendency for the hens
to take more recesses in the afternoon. Only 16% of the recesses of
these five hens included noontime (1200 hours).
Blakey (1937) reported that turkey hens tended to recess at
mid-day after the first few days of incubating, and Hillestad (1970)
stated that mid-day would be the best time for hens to recess because
air temperatures then most nearly approach required incubation
temperatures. The mid-day recess pattern was not predominant in this
Florida population. Only 10% (27) of 271 recesses occurred between
1130 and 1230 hours. A similar tendency for hens to avoid recessing
at mid-day was noted in a recent study in Michigan (Green 1982).
Recesses were less frequent in early afternoon than during late
afternoon (Fig. 16).
In Florida, the traditional closure of spring gobbler hunting
each day in early afternoon probably lessens the risk of incubating
hens on recess being shot by hunters.
The period of absence from the nest for hens that recessed at
noon averaged 137 minutes, whereas hens on recess in the morning
Table 4. Consecutive nest recesses of five Florida wild turkey hens
monitored during the period of continuous incubating behavior.
Fisheating Creek and Lochloosa study areas, 1968-82.
Length of Day of
Period of day recess incubating
of recess (minutes) Date behavior
Table 4, continued.
Length of Day of
Period of day recess incubating
of recess (minutes) Date behavior
aMorning recesses ended before noon; noon recesses began before and
ended after noon; afternoon recesses began after noon.
stayed away 129 minutes; the difference was not statistically
significant (P >0.05). Mean noon recess period of 137 minutes was
greater than the afternoon period of 91 minutes (Z = 2.03, P = .021).
The mean length of recesses for 128 adult and 32 yearling hens of 106
and 103 minutes, respectively, did not differ significantly (t =
0.097, P > 0.50). Recesses averaged 109, 95, 84, and 140 minutes
during the first through fourth weeks of continuous incubating
behavior, respectively (Table 5). The percentage of time hens spent
off their nests was greatest (10%) during the final week of
Green (1982) reported a mean recess time of 53 minutes for four
hens in Michigan (N = 41). The mean for 67 recesses of five Florida
hens was 95 minutes. The difference between the length of recesses in
Florida and Michigan was highly significant (t = 4.24, df = 113, P =
0.001). The Michigan study was conducted on a stocked population more
than 100 km north of the northern limit of the turkey's range in
Michigan; the present study was at the southern limit of the wild
turkey's range in the eastern U.S. The longer recesses in Florida may
be an adaptation to the warmer air and soil temperatures in Florida
where the eggs would not cool as rapidly in the hen's absence as they
might in Michigan.
The Incubation Period
The periods from the beginning of continuous incubating behavior
until the first poult hatched and until the brood left the nest
averaged 26 days (N = 7) and 27 days (N = 8), respectively (Table 6).
Healy et al. (1975) reported a mean incubation period of 28.6 days for
captive wild turkeys, but did not define the period or note the
Table 5. Average length of Florida wild turkey hen nesting recesses
during the period of continuous incubating behavior, Fisheating Creek
and Lochloosa study areas, 1968-82.
incubating Mean length Mean percentage
behavior Sample of recesses of time off
(days) size (minutes) nest
1- 7 38 109 8
8-14 35 95 7
15-21 48 84* 6
22+ 37 140* 10
*The difference between
these means was significant (Fisher's least
test, df = 154, t = 1.98, LSD = 55.66, P =
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occurrence of gradual onset of incubating behavior. In artificial
incubators, domestic turkey eggs require 26.92 days to hatch and
another 0.33 day for the poults to dry, which totals 27.25 days
(Abbott and Craig 1960). This latter figure does not provide for the
several hours required.for imprinting in wild broods and therefore
would be more comparable to the 26-day period required for the first
poult to hatch in wild Florida turkey nests.
The 27-day period of continuous incubating behavior for Florida
turkey hens measured in the present study was briefer than the 28 days
reported by Mosby and Handley (1943) or the 27.3 days (Abbott and
Craig 1960) and 28 days (Marsden and Martin 1949) reported as the
incubation period of domestic turkey eggs in incubators. The reason
for the disparity in incubation periods is that Florida wild turkey
eggs are incubated for approximately 25 hours during the laying period
before continuous incubating behavior begins. No incubation occurs
during the laying period when artificial incubators are used because
the eggs are removed from the nests and stored at cool temperatures
until they are placed in the incubator.
Little published data exist concerning the time required for
whole clutches of wild turkey eggs to hatch after the first egg has
pipped. Most writers, such as Mosby and Handley (1943), state that
the hatching of the entire clutch requires about 24 hours. Healy et
al. (1975) reported that an artificially incubated wild turkey egg
hatches within an interval of 4 to 21 hours, that whole clutches hatch
in 12 to 48 hours and that 8 hours are required for a poult to become
dry. Cook (1972) reported that two wild clutches hatched in 23.3 and
26.2 hours. In the present study, the interval between the time the
first egg of a clutch was observed pipping and the time at least one
poult was seen hatched ranged from less than 1 hour to 52 hours (Table
Hatching behavior was monitored in 14 nests, 7 by direct
observation and 7 by electronic nest recorders. Eight of the 14 nests
were inspected during the hen's last recess prior to hatching. In two
nests, one egg was pipped; in another, two eggs were pipped; none was
pipped in the other five nests. None of the 14 hens recessed after
the pipping stage.
Vocalizations of hens and poults in three nests were recorded by
monitoring microphones during the hatching process. Brood hens made a
number of calls that are used by turkeys at other times; however, two
calls were restricted to the hatching period. One is a hatching yelp
(Williams 1984) that begins with single notes at 500 Hz spaced about
0.5 to 1.0 second apart (Fig. 17); it is sometimes accelerated to more
than four notes per second. Images in sonograms have a resemblance to
quarter notes in standard musical notation. The hatching yelp is
uttered by the hen immediately after the poult peeps. Another
previously undescribed call peculiar to the hatching period, termed
the hatching hoot (Fig. 18), consists of a prolonged, 600 Hz note that
is given irregularly throughout the hatching period.
While in the nest, poults give peeping calls of three types (Fig.
19): a single note that is repeated; a two-part ascending and
descending note; and a multi-syllable call resembling the lost
whistling call that poults use when they become separated from the
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These five calls, which were heard from all seven nests monitored
by microphone, appear to be the basic vocal communications between the
hen and her poults. These are the sounds that enable the poults to
learn to distinguish the voice of their mother from other hens by the
second day of life (Ramsay 1951).
As the poults hatched and the nest became crowded, the hen moved
farther back, surrendering the front of the nest to the young. Poults
napped, mainly under the sides, tail, and drooped wings of the hen,
and sometimes ventured outside the nest during periods of activity.
When a poult ventured as far as 1 m from the nest, the hen would yelp
for it to return. Hens did not leave the nest or respond in any way
other than vocally when poults ventured out of the nest.
Hatchability was 89% (SD = 0.14) of 839 eggs in 85 undisturbed
nests. McDowell (1956) reported a hatching rate of 97% in 13 nests in
Virginia, and Everett et al. (1980) reported a rate of 95% in 14 nests
in Alabama. Green (1982) reported only 72% hatchability in a Michigan
study in which the stock was descended from pen reared turkeys.
The Imprinting Period
Parental imprinting is a learning process by which young birds of
many species become socially attached to their parents and gain self
identity as members of their own species (Lorenz 1937). Imprinting
takes place during the first few hours of life and is crucial for wild
nidifugous birds. Imprinting is said to be irreversible in the turkey
(Schein 1963). Although there is some dispute about the
irreversibility of imprinting (Salzen and Meyer 1968), it is, at the
least, persistent and very difficult to reverse (Fabricius 1962).
Much of the research on imprinting has been conducted with the
mallard (Anas platyrhynchos). Ducklings remain in the nest for 24-62
hours after hatching (Hess 1972), which is 10-12 hours after the last
hatched duckling is dry (Kear 1965). Imprinting is compete (Bjarvall
1967) or nearly so (Fabricius and Boyd 1954) by the time of nest
departure. Both auditory and visual cues are involved in imprinting
(Ramsay 1951). Auditory cues strengthen with time, reaching their
peak effect several hours after visual cues. This is probably because
the need for audible communication between the hen and ducklings is
greatest after they leave the nest and travel in vegetation where
visibility is obscured (Fabricius 1964). Visual cues for imprinting
are enhanced and following behavior is strengthed when ducklings make
short excursions from the nest and can see the hen while she is
calling (Bjarvall 1967). Ducklings without visual reinforcement
probably would not follow as strongly upon nest departure.
The imprinting process in the wild turkey is similar to that of
the mallard. Observations of seven turkey broods indicated that the
broods remained in the nest for variable intervals of time after the
last-hatched poult was dry and active. Hens vocalized softly during
this time and the poults made short excursions out of the nest and
returned at the vocal command of the hen. During the 10-minute period
prior to nest departure, hens called more frequently than before.
Upon departure, hens arose abruptly, stepped out of the nest without
hesitating, and moved slowly away while continuing to yelp softly to
In each of the seven brood departures, there was a gradient in
the strength of the following response among poults--some followed at
the hen's side whereas others straggled behind. In three cases, a
few poults failed to follow the hen farther than about 1 m from the
nest, which caused the hen to stop and yelp. In two cases, a few
poults remained in the nest, apparently more strongly attracted to it
than to the hen. They followed the hen only after she returned to the
nest and called to them.
Once an observation blind was erected too near a nest, which
caused the brood to depart prematurely about 6 hours after the last
poult had hatched. Three of the poults remained in the nest for 5
minutes during which time the hen called to them from a distance of
about 2 m. The hen had to return to within 1 m of the nest repeatedly
before the poults finally followed her.
Another brood hatched on 30 May and, due to investigative
disturbance, left the nest about 12 hours later. Four poults did not
follow the hen despite her continuous yelping. The observers left the
area so that the brood could reassemble; however, the next morning one
poult was found alone near the nest. Radio signals indicated that the
hen was still near. The observers again left the area. The following
morning, the four stray poults were found near the nest--the hen had
left the area without them. Three of the poults were captured
eventually by playing-back the sounds of hatching that had been
recorded at the nest 3 days earlier. The poults later became
parent-imprinted on humans, which indicated that they had not
imprinted on the brood hen. The foregoing observations suggest that
one of the reasons poults remain in the nest as long as they do after
hatching is to become adequately imprinted on the hen.
Time of Nest Departure by Broods
None of 28 broods departed the nest before sunrise or after
sunset (Fig. 20). Nineteen (68%) departed during morning hours.
Brood departure at mid-day was infrequent, corresponding to the
reluctance of incubating hens to recess at that time. Only one brood
departed after 1800 hours and it traveled only about 10 m before
roosting that night. No brood returned to its nest after departing.
Some birds with large clutches have adaptations that hasten the
hatching of the last laid eggs so that all the eggs hatch at nearly
the same time. Synchronized hatching is advantageous for nidifugous
birds with large clutches because it facilitates nearly simultaneous
parental imprinting and early nest departure of the brood. Hatching
synchronization is so well developed in the northern bobwhite that the
entire clutch usually hatches in less than 2 hours (Vince 1969).
If hatching is synchronized, the time required for hatching
should be less than the total incubating time experienced by the first
egg before the last egg is laid. The regression equation for the
onset of incubating behavior in the turkey (Fig. 11) shows that, on
average, the first eggs received approximately 25 hours of incubation
by the time the twelfth egg was laid. It would appear then, that in
taking more than 24 hours to hatch the clutch, the turkey exhibits
poorly developed synchronizing mechanisms.
Attendance of Infertile Eggs
Two incubating hens attended infertile clutches for 35 and 64
days. The hen that incubated continuously for 64 days exceeded the
normal incubation period by 37 days, incubating about 2.5 times the
normal period. The northern bobwhite has been reported to sit on
unhatched eggs as long as 56 days, or 2.4 times its 23-day incubation
period (Stoddard 1931).
There were too few nests on the Lochloosa Study Area to warrant a
detailed analysis of nesting habitat. Of 236 nests on Fisheating
Creek Study Area, 58% were in palmetto, 31% were in cypress woods, and
11% were in miscellaneous types of habitat (Table 8). The proportions
of the three habitats were 5%, 51%, and 44% for palmetto ecotone,
cypress woods, and miscellaneous types, respectively. Hens selected
nesting habitats in different proportions than they occurred on the
area (X2 = 1328, df = 2, P <0.001).
Cypress woods and palmetto habitats differed in plant species
composition (Table 9) and structure. The major structural difference
was a tree canopy in the cypress woods (Fig. 21), which was absent
from the palmetto ecotone (Fig. 22). Low vegetation in the cypress
woods habitat was fast-growing in contrast to the relatively
unchanging composition and structure of the woody vegetation that
predominated in the palmetto habitat.
Saw palmetto and wire grass occurred at all 44 nest sites in the
palmetto ecotone (Table 9). The foliar coverage of palmetto and wire
grass occupied more than 50% of the area within 1.5 m of 80% of the
nests and no less than 20% of the area near any nest site in this
Table 8. Number and proportion of 236 Florida wild turkey nests in
three habitat categories, Fisheating Creek and Lochloosa study areas,
Nesting habitat type
Year Palmetto Cypress woods Other
1968 16 (84%) 3 (16%) 0
1969 12 (86%) 2 (14%) 0
1970 15 (79%) 4 (21%) 0
1971 10 (71%) 1 ( 7%) 3 (21%)
1972 7 (50%) 7 (50%) 0
1973 12 (67%) 5 (28%) 1 ( 6%)
1974 12 (55%) 6 (27%) 4 (18%)
1975 11 (65%) 5 (29%) 1 ( 6%)
1976 7 (58%) 5 (42%) 0
1978 9 (75%) 0 3 (25%)
1979 5 (50%) 3 (30%) 2 (20%)
1980 8 (29%) 15 (54%) 5 (18%)
1981 12 (38%) 14 (44%) 6 (19%)
1982 1 (20%) 3 (60%) 1 (20%)
Total 137 (58%) 73 (31%) 26 (11%)
Table 9. Major plantsa occurring within 1.5 m of 63 Florida wild
turkey nest sites, Fisheating Creek Study Area, 1968-72.
Percentage occurrence in habitat
Palmetto Cypress woods Miscellaneous
Plant name (N = 44) (N = 15) (N = 4)
Taxodium distichum 100
Baccharis hamlimifolia 25
Callicarpa americana 20 25
Ilex glabra 25
Lyonia ferruginea 36
Lyonia lucida 73 25
Myrica cerifera 25
Quercus chapmanii 32
Quercus geminata 18
Serenoa repens 100 25
Smilax spp. 25 25
Rubus sp. 25
Vitis sp. 25
Aristida stricta 100 25
Quercus minima 64
Andropogon sp. 32
Vaccinium myrsinites 25
Panicum sp. 36 25
Axonopus compressus 95 25
Hydrocotyle umbellata 33
Centella asiatica 47
Saururus cernuus 20
Polygonum sp. 40
Rhus radicans 47
Hypericum sp. 25
Iris savannarum 25
Eupatorium coelestinum 73
Eichhornia crassipes 33 25
a Nineteen additional plants, mostly immature seedlings, that did
not occur at more than two nest sites, are not listed.
Figure 21. Investigator standing beside turkey nest in cypress
woods habitat, Fisheating Creek Study Area, 1981.
habitat. Lyonia lucida was the second most prevalent shrub at
palmetto nests, occurring at 32 sites (73%).
In cypress woods, cypress trees occurred within 1.5 m of all 15
nests, and the grass Axonopus compressus occurred near 13 nests.
Nests in the cypress woods usually were in the densest ground cover
available, which often was in semi-aquatic vegetation such as Centella
asiatica, Saururus cqrnuus, and Polygonum spp. (Table 9).
Each of the four nest sites in the miscellaneous habitat category
was in distinctly different vegetation: a narrow, dry ditch; a flood
control dike; a high, isolated saw palmetto clump; and a wax myrtle
thicket along a fence row.
Ninety-five percent of the 20 cypress woods nests and 87% of the
62 nests in palmetto had 40% or more vegetative cover within 2 m above
them (Table 10). Only one nest (5%) in the cypress woods and two (3%)
in the palmetto ecotone had less than 10% overhead cover. Thirty-
eight percent of the nests in palmetto had 70% overhead cover, and 24%
had more than 90% overhead cover. None of the nests in cypress woods
had more than 90% overhead cover.
Saw palmetto was favored for first, second, or third seasonal
nesting attempts (Table 11). Nesting habitat was used in similar
proportions by adults and yearlings (N = 223, X2 = 0.68, df = 2, P =
0.712). A higher proportion (68%) of nests in saw palmetto was
successful than in cypress woods (45%) (N = 148, X2 = 8.043, df = 2, P
Forty-two percent of 36 hens that were first observed nesting in
the palmetto ecotone renested in another habitat; 33% first observed
nesting in the "other" habitat type renested elsewhere; and 22% first
Table 10. Cover within 2 m above 82 nests located in cypress woods
and palmetto nesting habitats, Fisheating Creek Study Area, 1968-72.
Number and percentage of nests
cover Cypress woods Palmetto
< 30 1 ( 5%) 4 ( 6%)
31-40 2 (10%) 10 (17%)
51-70 6 (30%) 10 (17%)
> 70 11 (55%) 38 (61%)
Totals 20 (100%) 62 (100%)
Table 11. Proportions of first, second, and third nests of Florida
wild turkeys, established within a single season, by habitat type,
Fisheating Creek Study Area, 1968-82.
Percentage of nests
First Seconda Thirda All
nests nests nests nests
Habitat type (N = 191) (N = 38) (N = 7) (N = 236)
Palmetto 60 47 57 58
Cypress woods 30 37 14 31
Other 10 16 28 11
100 100 100 100
aThese were the first, second, or third nests observed. A few nests
were probably depredated during early laying stages; thus some nests
listed as second may have actually been third et cetera.
observed nesting in cypress woods renested in another habitat (Table
12). Although there seemed to be a preference for nesting in saw
palmetto cover, there was considerable variability in the nesting
habitat used in different years (Table 8). The tendency to change
freely from one habitat to another for renesting in the same year, and
between years, suggests that habitat imprinting may not be an
important factor in nesting habitat selection by the Florida turkey.
The earliest egg found in the study was laid on 6 March; the last
egg was laid on 6 June. The last clutch hatched on 2 July. The
median date of laying the first egg was 23 March (x = 25 March) and
the median date the last clutch hatched was 8 June (x = 10 June) (Fig.
23). Nests that were initiated after 1 May were probably the second
or third nests of the respective individual hens that season. The
molting pattern (Williams and Austin in press) of at least 3,000
juvenile turkeys examined during summer and fall on the Lochlossa and
Fisheating Creek WMAs substantiated that few poults were hatched after
Yearling hens began nesting about 2 weeks later and completed
nesting about 2 weeks earlier than adults (Fig. 24). The difference
was significant (N1 = 88, N2 = 25, Kolmogorov-Smirnov Z = 1.923,
maximum difference = 0.436, 2-tailed P = 0.001). Later initiation of
nesting by yearlings apparently occurs also in the Rio Grande turkey
as Smith (1977) reported that adult hens in Texas began copulating
before leaving their winter range whereas yearlings did not begin
copulating until after reaching their spring range.
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Nesting Success and Predation
Sixty percent of the 171 nests that were not disturbed by
investigative activities were successful (Table 13). This rate of
nest success is not necessarily an accurate estimate, however, because
not all the nests were-observed from the time of clutch initiation, a
factor that would tend to bias nest discovery in favor of successful
nests. The Mayfield (1961) method, which provides an appropriate
adjustment for nests observed during only a portion of their full
terms, was used to calculate nesting success. During the 14-year
study, eight nests were lost to predators during 218 days of exposure
within the laying period (Table 14). Thus 0.0367 (8/218) nests were
lost per day during the laying period. The daily probability of
survival for any nest would be 0.963 (1-0.0367). Inasmuch as
approximately 12 days are required for a clutch of 10 eggs to be laid
(one egg per day plus two lapse days in a typical clutch), the entire
laying period would be 12 days and the probability of a nest surviving
the 12-day laying period would be 0.96312 or 0.638. The probability
of survival to hatching for each nest during the incubating period,
using 27 as the number of days in the incubation period, was 0.708
(38/2987 1.0 = 0.0.9873; 0.0987327 = 0.708). The probability of a
nest hatching would be 0.638 x 0.708 = 0.452. Thus, the proportion of
nests surviving was 63.8% during the laying period, 70.8% during the
period of continuous incubating behavior, and 45.2% during the entire
nesting period. As expected, the latter figure is lower than the 60%
hatching success recorded for all nests under observation (Table 13).
Table 13. Fates of Florida wild turkey nests under observation,
Fisheating Creek and Lochloosa study areas, 1968-82.
All nests (N = 237)
Fate Number Percentage
Hatched 103 43
Predator 59 25
Flushed 42a 18
Deserted 31b 13
Flooded 2 1
alncludes 15 hens that were flush
bIncludes 23 hens that may have b
Nests not disturbed by
investigators (N = 171)
led intentionally; not all flushed
een disturbed by the investigators.
Table 14. Nest survival data used
successful nesting by Florida wild
Lochloosa study areas, 1968-82.
to calculate the probability of
turkey hens, Fisheating Creek and
Laying period Incubation period
Number of Days of Number of Days of
nests nest nests nest
Year depredated exposure depredated exposure
It is possible to take renesting into account in estimating the
success of the nesting hen population by using the probabilities
0.566 = the probability that a hen will renest if the nest is
lost during the laying period (see Renesting);
0.280 = the probability that a hen will renest if the nest is
lost during the incubation period (see Renesting);
0.638 = the probability that a laying hen will reach the
0.708 = the probability that a clutch that reaches the stage of
being continuously incubated will hatch;
0.362 = (1-0.638) = the probability that any nest will be lost
during the laying period;
0.292 (1-0.708) = the probability that any nest will be lost dur
the incubation period.
In calculating nesting success of the population, it is assumed
that all hens will attempt to nest and will renest once if the nest is
disrupted during the incubating period and twice if disrupted during
the laying period. These calculations yield
(0.638)(0.708) = 0.452 as the proportion of the first time
nesters that will be successful,
(0.362)(0.566)(0.638)(0.708) = 0.093 as the proportion of hens
losing their nests during the laying period that will
(0.638)(0.292)(0.280)(0.638)(0.708) = 0.024 as the proportion of
hens losing their nests during the incubating period
that will successfully renest, and
(0.362)(0.566)(0.362)(0.566)(0.638)(0.708) = 0.019. as the
proportion of hens losing their nests twice during the
laying period that will eventually be successful.
Overall nesting success would be the sum of the products:
0.452 + 0.093 + 0.024 + 0.019 = 0.588 or 58.8%.
The calculated rate of nesting success may not accurately reflect
nesting success of the entire population because hens that were not
known to nest are not included in the calculations. If some of them
did not attempt to nest, which is likely, the overall nesting success
rate would be lower. Turkey populations on the study areas increased
during the period of study despite the nest losses to predators.
Nest predation was distributed evenly throughout the incubation
period (Fig. 25). Predatory species responsible for nest losses could
not be ascertained in every case, but evidence at nest sites indicated
that the raccoon (Procyon lotor) was a prominent predator in the
cypress woods, and that the striped skunk (Mephitis mephitis) and
spotted skunk (Spilogale putorius) were major predators in oak scrub
and palmetto. Other predators included the opossum (Didelphis
virginianus), gray fox (Urocyon cinereoargenteus), bobcat (Felis
rufus), and domestic dog. The American crow (Corvus brachyrhynchos)
destroyed only a single nest.
Potential nest predators that were not known to take eggs
included the feral hog (Sus scrofa), which has been reported to
depredate turkey nests (Barkalow 1942, Blakey 1937), and the armadillo
(Dasypus novemcinctus), which is suspected by many laymen of taking
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turkey eggs. Although armadillos did not eat any turkey eggs, they
rooted through two nests, rolling out some of the eggs and causing the
hens to abandon the nests.
A higher proportion of nests was depredated in the cypress woods
(55%) than in saw palmetto (32%) or in the "other" (21%) habitats (N =
148, X2 = 8.043, df = 2, P = 0.018). The "other" habitat category was
heterogeneous in plant species composition and structure, whereas the
cypress woods and palmetto were relatively homogenous. The lower
predation rate in the heterogeneous "other" habitats supports the
experimental findings of Bowman and Harris (1980), who predicted that
predation rates would be higher in homogeneous habitats.
Predator success is reportedly high when prey is abundant and
increases with hunting experience of the predators (Tinbergen et al.
1967). If these factors were important in the present study, nest
losses should have been higher in mid- or late season nests than in
early nests. However, predation rates did not differ among
early-season (hatching before 1 May), mid-season (hatching 1 May
through 20 May) or late-season (hatching after 20 May) nests (N = 117,
X2 = 2.6, df = 2, P = 0.26).
Predation is an important factor in the life and evolution of the
wild turkey. Nest losses to predators were 54.8% as previously
calculated and poult losses during the first 2 weeks were about 70%
(Williams and Austin in press). The annual turnover rate in turkey
populations has been estimated to range from 30% (Logan 1973) to 50%
The major behavioral adaptations of the turkey hen to avoid nest
predation are 1) selecting a well-hidden nest site, 2) laying eggs in
mid-day when the common nest predators are inactive, 3) covering the
nest with debris before leaving it during the laying period, 4)
minimizing activity near the nest, 5) remaining on the nest when
predators approach, and 6) sometimes flying to and from the nest
rather than walking.
The plumage of the hen is cryptically marked with brown and
black. Natural colors of the ground litter at nesting sites tend to
optimize the camouflage effect. Nests are covered lightly with a few
dead leaves when left unattended during the laying period. Overhead
cover of nests is at least 40% and sunlight through the vegetation
creates a broken pattern of light and dark spots, which accentuates
the cryptic effect of the hen's speckled back pattern or the
camouflage of dried litter covering the eggs.
Hens lay in mid-day at which time the major nest predators
(raccoon, opossum, and skunks) are inactive. It is unlikely that
predators would see the hen approaching her nest at mid-day or would
track her by scent when they emerge to hunt several hours later.
Hens do not linger near their nests. Laying hens spend their
inactive daylight hours away from the nest and roost at least 0.5 km
from the nest (Williams et al. 1974). When approaching the nest to
lay, hens move steadily and enter the nest quickly. If a hen sees a
person as she returns to the nest, she delays her approach but returns
quickly to the nest when the person leaves the area.
Eight hens were monitored from observation blinds and by
telemetry as they left their nests during the laying period. They did
not dust, rest, or feed until they had moved at least 200 m from the
nest. Only two hens of the eight were known to visit their nests
except to lay or incubate and each did so only once.
Hens chose dense cover for nesting, and remained motionless if
approached on the nest. The turkey's strategy of holding tightly to
the nest is a general defense strategy of many prey animals (Edmunds
1974). An observer approached within 6 m of 13 nests located in
palmetto habitat a total of 19 times; in no case did the hen flush
unless the investigator passed closer than 2 m. In seven cases, hens
returning to their nests were frightened away by an investigator who
was within 5 m of their nests; none abandoned.
In approximately 40,000 man-hours of field work only one active
nest was found accidentally. This finding, coupled with the
observations on nest holding behavior, suggests that disturbance of
hens on their nests by humans in cover conditions such as those on the
study areas, is minimal.
Turkey hens in Alabama (Wheeler 1948) and in the Rocky Mountains
(Ligon 1946) have been observed flying to and from their nests. In
the present study, 20% (N = 140) of the hens flew from or to the nest
site. In flying to their nests, turkeys usually landed 3-15 m away
and walked the remaining distance; when flying from the nest, they
took two to five steps before flying, often taking wing within 3 m of
Much has been written about nest abandonment as a result of human
disturbance of nesting hens (see Schorger 1966:265-266 for a review).
Logan (1973) reported that seven of nine hens in Oklahoma were flushed
repeatedly from their nests without abandoning. The two hens that did
abandon their nests were flushed during the laying period--the other
seven were flushed while incubating. Hens apparently have differing
tolerances to being flushed from the nest. Of the 38 hens flushed
from their nests a single time in the present study, 55% did not
return (Table 15).
It is widely believed that nesting hens are more likely to
abandon their nests if flushed during the laying period than if
flushed during the period of continuous incubating behavior (Schorger
1966). In this study, 60% of the hens that were flushed during the
period of continuous incubating behavior returned to their nests in
contrast to 38% of those flushed during the laying period (Table 15).
Although the observed behavior supports the consensus view on the
subject (Schorger 1966), the difference was not significant (X2 =
1.29, df = 1, P = 0.255).
There is evidence that a hen is more likely to return to her nest
if flushed late in the incubation period than during laying or early
in the incubation period. The return rate was 38% for hens flushed
during the laying period, 42% for hens that had incubated less than 8
days when flushed, and 60% for hens that had incubated longer than 8
days (Table 15); these differences, however, were not statistically
significant (X2 = 0.84, df = 2, P = 0.359).
Habitat type appeared not to influence nest abandonment.
Thirty-nine percent of the hens flushed from nests in the cypress
woods returned as compared to 59% returning to nests in palmetto (X2 =
1.61, df = 1, P = 0.446) (Table 16). However, a higher proportion of
yearling hens (73%) abandoned their nests after being flushed than did
adults (44%) (X2 = 2.751, df = 1, P = 0.097).
Table 15. Number and percentage of Florida wild turkey hens returning
to their nests after being deliberately flushed a single time by an
observer, Fisheating Creek Study Area, 1968-82.
Nesting period hens flushed N %
Laying period 8 3 38
First week of incubation 19 8 42
After first week of 10 6 60
Incubation period 30 18 60
Entire nesting period 38 21 49
Table 16. Number and percentage of Florida wild turkey hens by age
class and habitat type that returned to their nests after deliberately
being flushed by an observer during the laying and incubation period
combined, Fisheating Creek and Lochloosa study areas, 1968-82.
Habitat type or Number of
age class hens flushed N %
Palmetto 22 13 59
Cypress woods 18 7 39
Adult 32 18 56
Yearling 11 3 27
Wild turkey hen flocks dissolved in spring as the hens
established new home ranges and began to visit nesting cover. Nests
were not prepared in advance of laying. Hens scratched away leaves
and soil to make shallow depressions and deposited their first eggs on
the bare soil in mid-day. Saw palmetto with wiregrass, in an ecotone
between oak scrub and saw palmetto prairie, was the favored nesting
habitat. A substantial proportion of the hens also nested in cypress
woods and in miscellaneous habitats. There was much variation in the
use of different nesting habitat from year to year and from one nest
to the next within the same season by the same hen.
Before a hen departed the nest after laying, she partially
covered the eggs with leaf litter picked up from beside the nest. Each
time she returned to lay another egg, the hen settled on the nest
without removing the litter. This habit camouflaged the nest and
produced the leafy lining characteristic of the completed nest.
Hens averaged about 1 hour at the nest while laying each of the
first 5 eggs, which were deposited from a standing position. Laying
was irregular at first--i to 3 days being skipped early in the laying
period before laying became a daily event. Hens rarely visited their
nests except to lay or incubate. After five eggs had been laid, hens
remained on the nest longer with each subsequent laying. This
behavior initiated incubating behavior gradually. By the time the
last egg was laid, hens were remaining on their nests from mid-day
until late afternoon. Most hens remained on the nest overnight for
the first time on the same day the last egg was laid, and continued to
incubate overnight except for daytime recesses during the remainder of
the incubation period. Incidents of more than one hen laying in the
same nest and of egg-dropping occurred only infrequently. The hens
exhibited characteristics of a determinant laying species.
Hens usually left their nests only once every 2 days although
some hens remained on the nest for a span of 4 days without a recess.
Recesses averaged 98 minutes. Most recesses were taken in the morning
or afternoon; mid-day recesses were infrequent. Successive recesses
were not routinely taken during the same time of day.
Hens did not cover their eggs when on recess during the
incubation period as they did during the laying period. Hens turned
their eggs during both the laying and incubation periods. Eggs rolled
intact from the nest were sometimes placed back in the nest by the
hen; however, hens usually abandoned nests containing a broken egg.
The first poult was hatched after about 26 days of continuous
incubating behavior. Although the gradual onset of incubating
behavior resulted in about 25 hours disparity in the amount of
incubation experienced by the first and last eggs, hatching
synchronization appeared to be poorly developed. The brood remained
in the nest for at least one-half day after the hatching of the last
poult. Parental imprinting of the poults was facilitated by frequent
voice communications between the hen and brood. The brood usually
departed the nest in the morning before the end of the twenty-seventh
day after the beginning of continuous incubating behavior.
Average clutch size was 10.3 eggs. Clutch size of adults and
yearlings differed, being 10.5 and 10.0 eggs, respectively. There was
no difference in the number of eggs in first, second, or third nests
or for early vs late nests in the same year. The two largest clutches
contained 17 eggs. Incubated clutches with fewer than five eggs were
not found, probably because hens are not adequately stimulated to
incubate fewer than five eggs. Egg hatchability averaged 89%.
Turkey nests were established in heavy ground cover and were well
camouflaged. Incubating hens held tightly to their nests when
approached by a human or potential predator. This behavior probably
increased nesting success inasmuch as flight by the hen usually would
reveal the location of the nest, and thereby increase the probability
of its destruction. About one-half of the nests were destroyed by
predators; however, when renesting was considered, nearly 60% of the
nesting hens were successful in hatching a brood. Major nest
predators were the raccoon, stripped skunk, spotted skunk, and
opossum. Predation incidents were distributed evenly throughout the
period of continuous incubating behavior. Laying hens renested more
readily than incubating hens; adults renested at about twice the rate
The nesting season extended from early March, when the first
nests were established, to early July, when the last clutch hatched.
The median date of nest establishment was 23 March; the median date of
the last hatching was 8 June. Thus, the nesting season for the
Florida turkey is essentially restricted to the months of April, May,
Nesting Florida turkey hens are secure from serious levels of
disturbance associated with spring gobbler hunting or other human
presence in their habitat because of the dense nesting cover used and
the tenacity with which they hold to the nest in the presence of
humans. Even when disturbed, approximately half of the hens that were
flushed from their nests returned and continued normal nesting
activities. Furthermore, 39% of the flushed hens that abandoned their
Incubating hens leave their nests infrequently for very short
periods and would not likely be encountered by hunters. Furthermore,
more than half of their recesses are taken in afternoon during which
time spring gobbler hunting in Florida is not permitted. There would
be no advantage in setting the spring gobbler hunting season to
coincide with peak incubation activity for the purpose of protecting
nests from dispruption because the net impact on reproduction is the
same regardless of whether the hen is flushed while laying or while
Although hens exhibited a strong preference for nesting in the
ecotone between oak scrub and saw palmetto prairie, and in cypress
woods, the highest rate of nest success occurred in habitats other
than palmetto or cypress. Because of the great variation in nesting
habitat used from year to year and the strong tendency of hens to
renest freely in a habitat different from that of the earlier nest,
manipulation of nesting cover is not warranted at this time. However,
it would probably be beneficial to preserve much of the palmetto-scrub
ecotone in habitat occupied by the turkey in Florida.
Abbott, U. K., and R. M. Craig. 1960. Observations on hatching time
in three avian species. Poult. Sci. 39:827-830.
Aldrich, J. W., and A. J. Duvall. 1955. Distribution of American
gallinceous game birds. U.S. Fish and Wildl. Serv. Circ. 34.
American Ornithologists' Union. 1982. Thirty-fourth supplement to
the American Ornithologists' Union check-list of North American
birds. Auk 99:1CC-16CC.
Audubon, J. J. 1831. Ornithological biography. Vol. 1. Adam Black,
Austin, D. H. 1965. Trapping turkeys in Florida with the cannon net.
Proc. Annu. Conf. Southeast. Assoc. Game and Fish Comm. 19:16-22.
T. E. Peoples, and L. E. Williams, Jr. 1973. Procedures for
capturing and handling live wild turkeys. Proc. Annu. Conf.
Southeast. Assoc. Game and Fish Comm. 26:222-236.
Bailey, R. W., H. G. Uhlig, and G. Breiding. 1951. Wild turkey
management in West Virginia. Conserv. Comm. of W. Va.
Tech. Bull. 2. 49pp.
Barkalow, F. S., Jr. 1942. Inventory of wildlife resources. Pages
59-61 in Annual Report of 1939-40. Ala. Dept. Conserv.,
Bendire, C. E. 1892. Life histories of North American birds. U.S.
Natl. Mus. Spec. Bull. 1, Vol. 1. 446pp.
Bent, A. C. 1932. Life histories of North American gallinaceous
birds: orders Galliformes and Columbiformes. U.S. Natl. Mus.
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