Home Range and Seasonal Act ivity of the Eastern I�d igo Snake,
Drymarchon cora is couperi, in Northern Florida
by
Paul E. Moler INTRODUCTION
Tne eastern indigo snake, Orymarchon cora is couperi, is tht> long�st spe�i-:!s
of snake in th e United States (Conant 1975). Most accounts .of its natural
'h istory ·have emphasizt!d its assoc iation with xeric sand ridge hab itats
(sandhills) and its dependence on th� burrows of the gopher torto iie (Gopherus po·lyphemus) for overw inter ing (�/right and Wright 1957, Mount 1975, lawler
1977, Speake et al. 1978, Landers and Speake 1980, Speake and McGlincy 1981;
U.S. Fish and Wildlife Service 1982, Diemer and Speake 1983). Although acknowl edgi rig that the ind igo snake inhabits a wide var iety of hab itats in south Flor ida, many authors have reported that it is largely restr icted to xeric hab itats farther· north (Carr 1940, Lawler 1977, USFWS 1982). L·awler
(1977), for example, states, "In Florida, Orymarchon remains int imately assoc iated with the sandhill habitat north of lake Okeechobee, although it is not uncommon to find wandering ind ividuals in decidedly mes ic situat ions".
Although the indigo snake is apparently rore or less restr icted to the vicin ity of sandh ill hab itats in Georg ia (D iemer and Speake 1983) and the western Flor ida panhandle, th is observation has overshadowed the fact that it occupies a wide var iety of non-xer ic habitats throughout the Florida peninsula. In the central and northern portions of the Florida peninsula, the indigo snake does occur in xeric hab itats, and in such situations may well require gopher tortoise ,burrow_s as refuge's fr om both the .cold of winter and the des iccating heat of summer (Bogert and Cowles 1947). However, it is not restr icted to such habitats, occurring regul�rly in·� var iety of other habitats far removed from sandh ills and gopher tortoises. It is common, for example, in cabbage palm (Sabal palmetto) dominated hammocks iri eastern Orange County . --·
(R. Demmer, personal communication) and hydric hardwood hammocks of coastal
Levy County. At Saint Marks Nat ional Wildlife Refuge, Wakulla County, indigo 2
snakes are uncommon, but roost sight i ngs have occurred in areas of extens ive
mesic habitat (C. Gidden, personal commun icat.ion).
This study was initiated in 1981 to investigate habitat ut ilization by
indigo snakes in coastal hydr ic hammock habitats of. the northern Florida
peninsul a. Major funding was provided by the U.S. Fish and Wildlife Serv ice
· under Sect ion 6 of the Endangered species Act. As a· resul t of budget cuts,
federal fun ding was discontinued after one year, and this study was
terminated. Although the study was not cam p 1 eted, much data were co11 ec ted,
and it is the purpose of this paper to make available information on movements, hab itat utilizat ion and winter ing behavior of indig o snakes in a non:-xeric hab itat in northern Florida�
STUDY AR EA
The study was conducted in Gulf Ham mock Wildl ife Management Area north of
Yankeetown, Levy County, Fl orida. Gulf Hammock WMA is a 12,000 ha publ ic hunt ing area 'leased by the Fl orida Game and Fresh Water Fish Com mission from
Georgia-Pac ific Corporat ion, It is. bordered to the west by Waccasassa Bay
State Preserve, an area of extEnsive coastal salt marsh. The area is general ly less than 6 m e.levation above sea level. Two of the snakes were caught and tracked in areas of approximately 1.5 el evation near the western boundary of m the study area. ·The remaining threi snakes were caught and tracked in an area lying bet�een 3-4.5 m elevation.
· The area is poorly drained and includes numerous shal low seasonal ponds.
Soils are thin, and limestone ,bedrock is near the surface. The area was originally cove red by hydr.ic hardwood hammock,· but has been extensively 3
clear-_cut. Older cleared areas have been site-prepared by windrowing and
planted · with slash pine (Pinus .elliottii) . Areas more recently cleared have
received no site preparation or have been site-prepared by windrowing, but have
not been planted with pines. Success of the planted pine� is spotty, and even
within the planted areas there are extensive regions with few pines. Most of
the cleared areas utilized by snakes in this study had been cut 3-10 years
earlier and were thickly overgrown with a variety of saplings and shrubs.
Private inholdings provided patches of mature hammock, and all five snakes had
access to both cut and uncut .habitats. Although most trees had been removed,
c�bbage palms �nd live oaks (Quercus virginiana) are.of little commercial value
and had not been cut. Cabbage palms grew principally in the wetter areas and
around ponds. The large live oaks stood as sentinels scattered widely through
the e�tensive clear-cuts. The bases of these oaks generally were surrounded by
earth· m6unds with hol�s left by rotted root channels or rodent burrows.
MATERIALS AND METHODS
Five adult indigo snakes wer e captur ed in the study area, equipped· with
surgically implanted tr ansmitter s and returned to the sites where they were
captured. Table 1 provides vital statisti.cs for the animals tracked. The
single female was equipped with an AVM Instrument Company SB2-tV transmitter
powered by an EVEREADY Hg601 me.rcury battery; package weight was 33 grams.
The males were substantially larget and able to accomod�te a larger transmitte�
·package. Three males received AVM SB2 transmitters powered by two Panasonic
2/3A lithium batteries. All fotir of the above transmitters were equipped with.
46 em long antennas made of 32 gauge Teflon coated hook-up wire (Alpha Wire 4
Corporation). The transmitter-battery packages were potted in dental acrylic
and then dip ped in a 1: 1 mixture of beeswax and paraffin; 582 packages measured
6 em X 3.3 em X 1. 6 cm and weighed 43 g. The fifth snake was equipped with a
cylindrical preassembled Telonics transmitter weigh ing 30.1 g. and m asuring e 6 em X 2 em. This unit was equipped with a 44 em long braided stainless steel
antenna. Transmitters operat d at frequencies between 150.000 and 152.000 e MHz.
Transmitters were surgically implanted following the methods of Reinert and
Cundall (1982). Snakes were anesthetized by placing them in a closed glass
container with a small gauze pad ·onto which Halothane had been poured. Once
anesthesia had been induced , the snake was removed from the container, and an
incision was made throu gh the skin above the second scale row approximately 3/4
of the way back from the head. A subcutaneous pocket was worked ventrally
. below the ribs, and blunt dissection was used to open the peritoneal cavi ty. A
finger was used to create an intraperitoneal pocket, and the transmitter was
inserted. A 56 lorig piece of stainless ste �l tubing (sharpened on one end) em was beneath the lateral skin forward from the incision a su fficient run distance to accomodate the antenna, and the antenna was inserted into the
tubing. The tubing was then removed through the skin at .its forward end.
Thus , the antenna was implanted subcutaneou sly alo�g the side of the body. The
incision was then sutured. Prior to implant tion the tr��smitters were soaked a f6r several hours in an antiseptic solution, but no antibiotics were ap pl ied to
the .transmitter or admin1stered to the snakes. 5
The snakes recovered from the anesthesia within an hour . Each snake was returned to its originai capture site and released within 6-12 days following tran$mitter implantation. Subsequent observations indicated that the incisions healed quickly and without apparent infection.
Tracking was usually conducted at periods of 1-8 days (.x = 3.8) fr.om early
December 1981 to mid-July 1982. Following termination of the project, the area was revisited 6 times between 18 July 1982 and 7 Apr il 1983 at intervals of 20,
14, 58, 31, 50 and 90 days. Snakes were tracked with a Telonics receiver equipped with a hand-held H antenna. The range of the transmitters used with the male snakes was at least 1.2 km in open country, but varied under field conditions depending upon location of the snake and density of the vegetation.
Locations of snakes were determined either by triangulation fr om known points or by pacing the distance and .using a compass to determine direction back to a known point. Locations were plotted on aerial photographs and then mapped on a grid overlay; x and y coordinate values were assigned to each site. Home range estimation follows Jennrich and Turner (1969). For calculation of winter home range, each radiolocation was treat�d as a separate sample· point, even though the snake was often tracked to the same point on consecutive tracking visits. For calculation of total home range and summer home r�nge, location was included only once unless the snake left the area a and then returned to the site a second time. For example, during the process of shedding, snakes typically remained in one spot for periods of 10-20 days.
Although the snake might have been found at the same site on three or four 6
consec�tive tracking visits, the site was included only once in determining
total anq summer home ranges.
RESULTS
The five snakes were regularly tracked for periods of 134-178 days. Three snakes were tracked infrequently following termination of the project, for
total tracking periods of 301-441 days (Table 1). Figures 1-6 summar ize movements of each snake.
Instrumented snakes were released between 1 December and 6 February. Two snakes (0854 and 1074) moved long distances imme diately following their release; these movements were not considered in �etermining winter home ranges because they may well represent response to handling. Winter home ranges were
calculated for the period 1 January - 16 March.
Although the snakes were frequently observed on the surface during the winter months (27-71% of radiolocations; 42%), they were seldom far from x = favored retreats. Nonetheless, two .of the male snakes made brief round trip journeys to distant points during mid-February. Numbers 0854 and 1124 were found at distances of 880 m and 80 m, respectively, from their primary retreats, but had returned by the _following tracking visit. In both cases, the round trip was made in not more tha.n seven days. Indigo snakes breed during late fall a�d winter (November-H�rch) (Speake et al. 1978), and such forays may be made in search of females. Number 0854 had made move of approximately a 180m in mid-January, at which time he was found in the company of a female.
The five snakes were observed to use 16 different winter den sites a total of 58 times (Table 2). They were close to several of these same sites on 7
numerous other occasions, but use of a den was recorded only if the snake was . tracked to the den or observed to move to the den when approached. Hollow root channels and rodent·burrows at the base of large live oaks represented the most important class of den sites (56% of sites, 59% of observations). All five snakes used at least one site of this ty pe. Only one limerock solution hole was used, but it was used by two different snakes (0854 and 1124) at different times. Hollow logs were used by two snakes and· armadillo burrows by three.
Each snake used .at least three different winter den.sites.
Activity of all five snakes increased in mid to late March. Two snakes
(0854 and 1221) made long distance moves away from the1r wintering dens, traveling distances of 1700 m and 820 m, respectively, before settling into a more typical pattern of movements. These initial moves away from the dens are not included in the summer home range calculations, although they are included in the calculation of total home ranges. Calculated summer· home ranges include only those radiolocations fr om the period 30 March - 7 August.
Home ranges were calculated 1) as the area of a convex polygon, 2) as th e area of a convex polygon corrected for sample size bias and 3) as an estimate based upon the covariance matrix of the capture points (Jennrich and Turner
1969). Calculated home ranges are presented in Table 1.
Four of the five snakes occ1:1pied summer ranges including or adjacent to areas of mature hydric hardwood hammock, yet only one (1221) made extensive use of this habitat. The remaining three (0854, 1074, 1124) were frequently found at the ecotone between mature hammock and clear-cut areas but were rare 1 y found within the mature hammocks. 8
Four snakes were frequently found" along the edges of ponds during spring and
summer. Ponds accounted for 25-68% ()('=39%) of all locations for these animals.
Of three snakes tracked into the fall, two are known to have revisited one of their den sites of the previous winter. In mid-Octobert 1074 was found at
the site previously occupied 24 January - 9 Februaryt but in mid-November and early January he was nowhere near his den sites of the previous winter
(Fig. 3). In mid-November, 1124 was found at the site previously occupied 24
January - 10 March; his signal could not be located on the subsequent visit in early January. The infrequency of fall records precludes any determination of winter den site fid elity.
There was indication of at least partial synchrony of shedding. The three snakes released on 21 January were all observed to be opaque (a condition preceding shed ding) during the first week of February. The only snake released prior to 21 January (0854), was below ground on all three tracking visits between 25 January and 7 February, so it. is not known if he was also opaque at this time. Neill (1949) suggested that injured indigo snakes shed more frequentlyt and it·is possible that the synchronous shedding was in response to the surgical implantation of the transmitters three weeks earlier. However, in mid to late April, within three· to four weeks after leaving their w.inter den sites, four of the snakes are known· to have shed again. The fifth snake (1221) stayed in one spot for 15 days, behavior typical of the other animals known to have shed at this time, but he was not seen. Little more than a. roonth later, two snakes (1074, 1124) were again observed to be opaque, and again, during 9
this period, 1221 remained below ground at one site for a period of at least one week. Number 1124 shed again in late June and again in early August. This one individual, thus, shed at least five times within a period of 200 days (22
January - 10 August). Because the shedding cycle typically involves a period o f a t 1 e a st 1 4 d ay s o f i n a c t i v it y , t h i s i n d i v i d u a 1 s e e m i n g 1 y d e v ot e d approximately one-third of its time to ecdysis.
DISCUSSION
Home Range
A major di f ficulty in attempting to compare results of this study with other studies derives from the lack of uniform calculation of home range. Although the convex polygon method of estimating home range "has historical prominence"
(Brown and Parker 1976), it suffers from a considerable sample size bias.
Jennrich and Turner (1969) demonstrated through sampling simulation that even with sample size of 25 , a convex polygon estimates only slightly rrore than a hal f of the actual range. Values derived from convex po1ygons can be corrected for sample size bias if sample size.is known, but often this information is not provided. Jennrich and Turner (1969) also suggested a method· for calculating home range based on the covariance matrix of sample points to estimate the smallest area which "accounts for 95% of an animal's utilization of its habitat11• All three methods have been used to calculate the values in Table . .
1. There is reasonable concordance between the values derived by the corrected polygon and by calculation from the covariance matrix; the values derived by the corrected polygon method will be used in the following discussion. 10
Table 3 compares home ranges of indigo snakes in this study with those
reported for other species. Fitch and Sh irer (1971) commented, "Vag ility is
remarkably low in snakes, at· least in most of the (8) kinds studied". Indigo
snakes are clearly an except ion to their observation. Speake et al. (1978)
reported that fall is the period of maximum movements for indigo snakes in
Georgia. Since the fall mo nths were excluded from the present study, the
values calculated here probably underestimate annual home range. It is clear
from the estimated total (48.2 - 533ha; �=224ha) and summer (34.2- 562ha;
�=158ha) home ranges that the indigo snake is an active and wide ranging
predator.
Habitat Utilization
Almost the ent ire summer range of 1124 had been clear-cut some 10 years
earlier, but all four of the remaining snakes had ready access to areas of
uncut hammock. Nonetheless, only one (1221) made extensive use of this
habHat. The remaining three snakes were frequently found near the ecotone
between hammock and cut areas, but were rarely found more than 10 m into the
hammocks. Most of the uncut hammocks had closed canopies and relatively little
understory. The hammock which was extens ively used by 1221 had a more open canopy and supported a denser understory. It also included numerous shallow
seasonal ponds.
As mentioned, snakes w_ere found in association with ponds in 25-68% of
tracking visits. The snake most often associated with ponds also utilized the
most extensive summer home range (562 ha). Much of this area was relatively
dry, and 1124 ·frequently moved long distances between ponds.· On one occasion, 11
over a period of less than 18 days, he moved from one pond to another 1.13 km
away and then back to the original p nd . His seeming preference for wet areas o and his extensive movements between ponds may account for his large home range.
Except when shedding, indigo snakes were typically active above gro�nd when
tracked during the spring-summer months. When preparing to shed, they usually
became sedentary for period of 10-20 days. At these times they took shelter a in a var iety of sites, including hollow ·logs, stum p holes and the holes
generally found around the bases of large oaks.
Speake et al. (1978) reported on a study of the eastern indigo snake in
Irwin County , Georgia,· some 340 km. north of the site of the present st dy . u They -reported mean May-July ranges of 42. 9 ha and mean August-November ranges
of 97.4 ha, but they did not indicate how ranges were calculated, so comparison
of the present study with their data is not possible. However, seasonal activity patterns do appear to differ between the two study sites. Speake et al. (1978) reported mean seasonal ranges of 4.8 ha for the period December
April and commented that the "shift from winter dens to sum mer territories" occurred during the May-July per i od . As noted earlier, snakes in the present study l�ft their winter den sites in mid to late March. Thus, summer activity apparently begins 4-6 weeks earlier at the more southern latitude.
Conse vat i on r The indigo snake is currently listed as a Threatened species by the
U.S. Fish and Wildlife Service (Fed. Reg. 43(21):4026-4028) and the Florida
Game and Fresh Water Fish Co mission. Although forme ly over-collected for the m r pet trade, federal protection since 1978 has largely eliminated the commercial 12
trade. Probably the greatest remaining threat to indigo snakes is degradation
or loss of habitat (Lawler 1977, Diemer and Speake 1981, U.S. Fish and Wildlife
Service 1982). The indigo snake is most common in areas of extensive
undeveloped habitat. This is hardly surprising. Given its large home range
and extensive movements, the indigo snake is especially vulnerable to road
mortality as wild areas become increasingly divided. Also, the indigo snake is
large, relatively slow and completely diurnal, so it is more apt to be noticed
and killed by an uninformed public. In this regard, even low density
development (e.g., 5-10 ha "ranchettes") represents a potential threat to
indigo snakes, for an individual snake may range over 20 or more parcels,
increasing the likelihood of being killed by a domestic dog or insensitive
landowner.
As the xeric habitats more traditionally regarded as Drymarchon habitat continue to be developed� areas such as the Gulf coastal. lowlands of northern
FJorida will become increasingly significant. It is imporant therefore that the value of these areas as indigo snake habitats be recognized.
It is apparent that relatively intensive forestry need not be inconsistent with the conservation of indigo snak�s. The snakes in this study seemed to prefer disturbed areas to virgin tracts, and the early successional stages alroost certainly support greater· populations. Speake et al. (1978) no ted the importance of windrows to sandhill populations of indigo snakes in Georgia.
Windrows were commonly used by snakes in this study as well. Land managers should be encouraged to leave windrows and slash piles rather than burn them. 13
There is another management concern in non-xeric habitats. In the absence of gopher tortoises, indigo snakes need alternat ive winter den sites. In this ' study, mature live oaks were important because of the hollow root channels and rodent burrows to' be found around their bases. Unfortunately, although these trees are not normally cut, it is common practice to girdle or poison them to make room for more c mercially valuable trees. Even after they die, these om trees will continue to provide den sites for many years, but they will eventually be lost , and replacement may take .centur ies. The practice of killing these mature oaks should be discouraged. 14
LITERATURE CITED
Barbour, R.W., M.J. Harvey and J.W. Hardin. 1969. Home range; roovements, and
activity of the eastern worm snake, Carphophis arooenus arroenus. Ecology
50 (3) :470-476.
Bogert, C.M. and R.B. Cowles. 1947. Re sults of the Archbold Expeditions.
No. 58. Moisture loss in relation to habitat selection in some ·Floridian
reptiles. Amer. Mus. Novitates (1358) :1-34.
Brown, W.S. and W.S. Parker. 1976. Movement ecology of Coluber constrictor
near communal hibernacula. Copeia 1976 (2):225-242.
Carr, A.F. 1940. A contribution to the herpetology of Florida. Univ. of
Florida, Biol. Sci. Ser. 3:1-118.
Conant, R. 1975. A field guide to reptiles and amphibians of eastern and
central North America, 2nd edition. Houghton Mifflin Co. , Boston.
Diemer, J. E. and O.W. Speake. 1981 . The status of the eastern indigo snake in
Georgia. pp . 52-62 .!!! R. R. Odom and J.W. Guthrie. Proc. Nongame .and
Endangered Wildl. Symp. Ga. Dept. Nat. Resources, Game and Fish Div. Tech.
Bul l . WLS.
Diemer, J.• E. and D. W. Speake. 1983. The distribution of the eastern indigo
snake, Drymarchon corais coup�ri, in Georgia. J. Herpetol. 17(3):256-264. Fitch, H.S. and H.W. Shirer. 1971. A radiotelemetric study of spatial
relationships in some common snakes. Copeia 1971 (1) :118-128.
Jennrich, R.I. and F.B. Turner. 1969. Measurement of non-circular home
range. J. Theoret. Biol. 22:227-237. 15
Landers, J. L. and D. W. Speake. 1980. Management needs of sandhill reptiles in
southern Georgia. Proc. Ann. Conf. S. E. Assoc. Fish and Wildl. Agencies.
34:515-529.
Lawler, H. A. 1977. The status of Drymarchon corais couperi (Holbrook), the
eastern indigo snake, in the southeastern United States. Herp. Review
8(3) :76-79.
Mount, R.H. 1975. The reptiles and amphibians of Alabama. Auburn Univ. Agr�
Exp. Sta., Auburn, Alabama. vii+ 347pp.
Neill, W.T. 1949. Increas�d rate of ecdysis in injured snakes: Herpetologica
5:115-116.
Reinert, H.K. and D. Cundall. 1982. An improved surgical implantation method
for radio-tracking snakes. Copeia 1982 (3) :702-705.
-----, and W.R. Kodrich. 1982. Movements and habitat util ization by the massasauga, Sistrurus catenatus catenatus. J. Herpetol. 16(2) :162-171.
Speake, D. W., J. A. McGlincy and T.R. Colvin. 1978. Ecology an·d management of
the eas-tern indigo snake in Georgia: a pr ogress report. pp. 64-73 In
R.R. Odom and L. Landers (eds ) Proc. Rare and Endangered Wildl . Symp., Ga. � Dept. Nat. Res. , Game and Fish Div. , Tech. Bull. WL 4.
---' and J. A. McGlincy. 1981. Response of snakes to as in ----- indigo g g s of their dens. Proc. Ann. Conf. S. E. Assoc. Fish and Wil dl. Agencies.
35:135-138.
U. S •.Fish and Wildli{e Service. 1982. Eastern indigo snake recovery plan.
U. S. Fish and Wildlife Service, Atlanta, Ga. 23 pp. 16
Wright, A.H. and A.A. Wright. 1957. Handbook of snakes of the United States
and Canada Vol. 1. Comstock Publ. Assoc., Ithaca, New York. + 564pp. xx 17
ACKNOWLEDGMENTS
This work was funded jointly by the Florida Game and Fresh Water Fish
Commission and the U.S. Fish and Wildlife Service under the Federal Endangered
Species Program, Florida Endangered Species Project E-1.
Both B. Kermeen of AVM Instrument Co. and S. Tomkiewicz of Telonics provided assistance in developing the transmitter implants, and H. Reinert provided helpful advice. J. Stevenson, Florida Department of Natural Resources (DNR) provided authorization to collect snakes in Waccasassa Bay State Preserve.
Snakes were provided by T. Morrell and T. Rooks, Florida ONR, and
J. Hintermister. Assistance with radio implantation was provided by W. Ploss,
J. Diemer, D. Moler and W. Snead ..J. Hintermister, W. Snead, J. Diemer and
V. Sims assisted with radiotracking. T. Crown typed the manuscript. Table 1. Seasonal and total home range size for five indigo snakes in Gulf coastal lowland habit ts of the northern Florida peninsula. a
Total Total i'b. Total HarE Range Winter HarE Range {hal SlllllEr Hare Rarqe {hal Length .Weight Period fib. Radio COnvex COrrected (� %. COnvex COrrected 95 % COnvex COrrected 9:> % Snake Sex (m) (Kg) Tracked Days Locations Polyg:m Poly 0854 2.31 4.3 12/1/81- 196 50 281 533 648 7.2 17.1 9.5 32.8 81.2 00.2 d 6/15/� 1074 2.15 3.2 1/21/�- 351 41 23.2 48.2 57.1 1.0 2.6 6.0 18.8 54.1 47.4 d 1/7/83 1124 2.21 3.5 1/21/82- 301 48 204 386 428 2.3 5.7 8.1 204 562 480 d 11/18/82 1221 2.32 4.2 1121/82- 441 48 57.3 101 108 1.5 3.7 5.7 24.6 56.4 43.8 d 4/7/f!J 1309 1.78 1.3 2/6/82- 134 28 22.2 50.8 65.2 0.6 3.2 4.0 11.9 34.2 35. 7 9 6/20/85 lConvex p:>lyg::m corrected for sample size bias (Jennrich and Tt.rner 1969) 2ealculation based on covariance matrix of sample points (Jennrich and Turner 1969) Table 2. Types of winter (1 January - 16 March ) den sites and frequency of use by.indigo snakes in Gulf coastal lowland habitats of the northern Florida peninsula. Numbers in parentheses indicate number of separate sites involved. Limestone Base of Solution Ho 11 ow Armadillo Snake Oak Tree Hole Log Burrow Total 0854 14 (1) 9 (1) 1 ( 1) 24 (3) 1074 9 ( 4) 9 ( 4) 1124 4 .(1) 1 ( 1) 4 (1) 9 (3) 1221 4 (1) 5 ( 1) 1 (1) 10 (3) 1309 3 (2) 3 (1) Total 34 ( 9) 10 ( 2) 8 ( 2) 6 (3) 58 ( 16) Table 3. Mean t-oTe r� size (corrected for sarrple size bias) reported for otler �ies of snake. Hare � Staooard Snake (ha) Error Caqh?j?)is anoenus am::>enus .056 + .012 Barbour et al. (1969) 1 AQ Sistrurus catenatus catenatus .979 + .329 Reirert and .Ct.n:lall (1982) Co1 uber constrictor 1.45 + .810 BrtJt��TJ and Pa rker {1976) - ll'1)rTJl)1 Colu.t:a" constrictor f1aviventris ( d's) 5.26 + 1.22 Fitch and.Shirer (1971)2 l!)!mrchon cora is coup:ri (SumEr) 158 +101 This study lvalues calculated by Reinert and Cundall (1982) 2ealculated from the data of Fitch and Shirer (1971) ····························�· 0 I Ltan Figure 1. Total .home ranges of eastern indigo snakes. Stippling represents areas of uncut hammock. 4. •-:::...- -- - ·- -- - - _ - 21 s-14 --. - ..'- Hl-20 -- ,-.:-5 .22 -30 .31 . , • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 0 ••• 0 ••••••••••0 ••0 ••••••••••••• - •••••••• . :::::::::::::: �::: :·::� ::::::: �: � � �:::: � �:;:;:;: :: � � �: �:::;: �:;::: �;; �; �; �: ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: ;!!! :! i i!! i !iiii! • : '-••••••••• : :::::::::::::::::::::::0 ::::•• :·.·.·.·.·.. ·.· .··. .·.·..·· . · · .· · .· .· . ..· .·. .·.. ·. .·..·.·.. ··. .·.· . • • • . . •••••••••...... 0 ' ·.·. ·.··. .·.·.·.·-·. · ·.·.· 0 Figure 2. Movements and seasonal home ranges of Number 0854, an adult male indigo snake. Dashed line depicts winter range (1 January - 16 March); solid line depicts SU!T1Tler range {30 March - 15 June). Numbers indicate sequence of movements. Stippling represents areas of uncut hammock. • 0 •••••••o • 0 •••••• •• • • • • • 0 ••• 0 • '' o I o o o o' rll, 'iii! I I • 41 ::::: :�::: :::::::::: 0.I 200I :�{:�:�:>>�1 11lera · . ::::::: •••••••••:::� ::::0 :::: ...... • •. • . 0 0 . •••••. • • 0 0.0 •• 0 • . . . . • • 0 •••••. .. . 0 . • . 0 •••• • • • • • 0 • .....• 0 0 •• ••• . . ' . . ..' . • •. • .• •. • .• •. • . 0 ••••••0 ••• . :>>>>> ::::::::::::::::::::! �:;: i:!: i: � i i: i:;:; r 21• . . ' .. . 0 .••• . 0 ...... •. • •. •. 0 •••••. .. . • • • • 0 ••••- ...... 0 •••••••. -.. - • • .- .•••••••.: ...... 0 . <·:-:o:-:-:-:0:-:-:- •� i • . l3 •32 lli i!liliJJ 211-31 > �: �: �: >�:.. �: �:j ...... -...... 0 •••. ••••.. . . 0. • 0 . . • . . 0 . ••••. . .. . 0. .•• ...... : :: : : : . / --12-111 :::::::::: :: ::::::::::::::::::·: :: : "' I ; ::::;:: : ; ; ;: I :··:····:·: · :·· / ::- 7 // I :::::::�::::::::::::::: - ::::: }} 11 ·Ill I Ill II II II II ���d�lrll:::i! li:Iii Iii ::111111111111 IIIII I II: lllllllill llI ll illli 11111:::1: llilllllllllllillillllli :1 I lllil:lll IllJill IIIII il,l lllllill,lli iII, III I: I/, figure 3. Movements and seasonal home ranges of Number 1074, an adult male indigo snake. Dashed line depicts winter range (24 January - 16 March); solid line depicts summer range (30 March- 7 August). Numbers indicate sequence of movements. Locations 39-41 are the result of sporadic fol l - p visits during fa 11 and early winter ( 18 October - 7 January). Sti ppliowng u represents areas of uncut hammock: ' �20 21-25r- 0 500 13-17• .... 4-11 • 4,2'I I 1 l0-351 / e4·s I I; I; I I I I ... I I • • 39 I I I I 40-42 I I / I I I 11 • I • I I • ------2.47 43 3�------� ::::::::::::::::::::::::::::::::::::::::: Figure 4. Movements and seasonal home ranges of Number 1124, an adult male indigo snake. Dashed line depicts winter range (22 January - 16 March); solid line depicts sunmer range (30 March - 7 August). Numbers indicate sequence of movements. Locations 46-48 are the result of sporadic follow ..up visits during late sui11Tler and fall (21 August- 18 November). Stippling represents area of uncut harrmock.. an ...... > jl!\\lll!llil ii\JII : li IIIII !Ill! i\l I 111 Ill ! IIIIi II:III : I I �li! l ::III 1illl"ll�·��,:, : - : · :.:- ::· _ . . ; _· ::: - . : . /·� . :- : ·: :· ::·:<::- ::: : :-:-:,,08iC' : : :: :::::: : : :::::::: : : : : : : :::: : : : :::::: :::::: :::: ::: : ::::::: : : :::: ::::: : : : : : : : : : : : : :::::: ::: ::: :: : : :: :: : : :: ::::::::: : ::::: : :: :-::: 11: ;:: ::;:: iii :: :; : ;;;:: l!i!ii :r; :! l l�: .. 0 ••• 0. 0 0. 0. 0 0 ••••• 0. 0 •• 0 0 0 ••••0 0 0 • • • 0 0 •••••• 0 •••••••0. 0 ••••••••••••• 0 •• 0. ' ••0 0 •••0 ••••0 ••••• 0 ••••••• • • • • • • • 0 0 •••• ' ••••••••••• 0-••••• ...... - ...... ·· :: ::: ::::::::::::::::::::::::::::::::::::::: :::::::::: :: : .. :::::::::::::j::: :::: j: j:::::::::: . �: j:::::::::::::: _... ,. 2-5•. -· . / ·- ---· 1,6 7 Fi gure 5. Movements and seasonal home ranges of Number 1221, an adul t ma le indi go snake . Dashed line depicts wi nter range (22 January - 16 March ); sol id line depi cts summe r range (30 March - 7 August). . Numbers indicate sequence of movements . Loca t i ons 44-48 are the result of sporadic fol l ow-up vi s its duri ng fall , wi nter and spri ng (21 August - 7 April). Stippl ing represents an area of uncut hammock. • . • . • . • . • . • . • . • . • . • . • . • . • . • . • . • . • . • . • . • . • . • . • . 0 . ••••. . . . 0 . 0 . •••••••••. ... •••••••• ••••••••••0 ••••••••••0 •• •••••• • • • • • 0 ••••••••••••••••••••••0 ••••0 ••0 •• 0 ••••0 ••••0 ••••••••••••••••••0. 0 ••••••• • 28 25 0 300 mat era figure 6. Movements and seasonal home ranges of Number 13 09 , an adult female indi go snake . Dashed line depicts wi nter range (6 February - 30 March ) ; sol id line depicts summer range (30 March - 20 June). Numbers indi cate sequence of movements . Sti ppl ing represents areas of uncut hammock.