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mented landscapes. Proc. R. Soc. Lond. B. Biol. Sci. ulation sizes (Wilson and Porras, 1983) or cause local 267:139-145. extirpations (Cochrane, 1989; Delis et al., 1996). Sca- TYLER,M. J., L. A. SMITH,AND R. E. JOHNSTONE.1994. phiopus holbrookiiholbrookii (Harlan) is an anuran spe- of Western Australia. 2nd ed. Western Aus- cies that is dramatically affected by urban develop- tralian Museum, Perth, Western Australia, Austra- ment (Delis et al., 1996). A terrestrial found lia. throughout southeastern North America, S. h. holbrook- W.A.G.P. 1992. State of the Environment Report 1992. ii is a mesic-dwelling representative of a desert-adapt- Western Australian Government Printers, Perth, ed clade. Adult S. h. holbrookiiinhabit predominantly Western Australia, Australia. loose, friable soils typically derived from surficial WEIR,B. S., AND C. C. COCKERHAM.1984. Estimating sands and excavate burrows that are 5-30 cm deep, F-statistics for the analysis of population structure. remaining underground much of the year except Evolution 38:1358-1370. when heavy rainfall stimulates reproduction in shal- WRIGHT, S. 1978. Evolution and the genetics of pop- low, temporary ponds (Pearson, 1955; Hansen, 1958). 4. ulations. Vol. Univ. of Chicago Press, Chicago. In Florida, developers alter upland habitats in ste- reotypical ways, including the creation of retention Accepted: 1 May 2000. ponds, construction of roads, and erection of build- ings. Well-drained sand and soils of natural uplands are replaced with asphalt, sod, and ornamental plant- ings, which reduce the available burrowing habitat for both newly metamorphosed and adult S. h. holbrookii. Journalof ,Vol. 35, No. 1, pp. 141-145,2001 Copyright2001 Societyfor the Study of Amphibiansand Reptiles Habitat alteration may exclude from developed areas. We address two main questions in this study: (1) Can toads burrow in substrates typical of devel- Spadefoot Toads ( holbrookii oped areas? and (2) Do toadlets prefer naturally oc- substrates over those common in holbrookii) in an Urban curring developed Landscape: areas? The first question asks whether toads are ex- Effects of Nonnatural Substrates on cluded from developed habitats because proper bur- Burrowing in Adults and Juveniles rowing substrates are lacking. The second question asks whether toadlets prefer natural substrates. Al- KEVINP. JANSEN', Department of Biology, University of though providing less direct evidence of the fate of South Florida,Tampa, Florida 33620 USA spadefoot toads in urban areas, we hypothesize that if ADAM P. SUMMERS,Museum of VertebrateZoology, Uni- toadlets prefer natural substrates they will disperse versity of California,Berkeley, California 94720 USA further from the breeding ponds in search of such substrates and likely suffer increased mortality. PABLOR. DELIS, Science Department,Hillsborough Com- TreatmentSubstrates.-Treatment substrates chosen munity College,Tampa, Florida 33630 USA according to available substrates in urban areas and the dominant substrate used by S. h. holbrookiiin Flor- Urban development is a form of habitat loss or al- ida (Pearson, 1955) included sand taken from areas teration that can reduce the size and extent of local with known populations and three substrates populations (Minton, 1968; Wilson and commonly used for landscaping in Florida: an organic Porras, 1983; Cochrane, 1989). Community develop- soil mixture, decorative gravel (3-8 mm diameter), ment (Sj6gren, 1991; Vos and Stumpel, 1995) and road and St. Augustine sod. All substrates were dried to construction (Fahrig et al., 1995; Vos and Chardon, constant weight at 95?C except for the sod and then 1998) both splinter anuran habitat. Proximate causes divided into one of three moisture regimes. Substrates of anuran decline are sometimes apparent (e.g., road were dry, maintained with 6-8% water (referred to as mortality) but often are not well understood (see Delis "moist" hereafter) or saturated with water. All sub- et al., 1996). A 500% increase in urban land use over strates used in the adult burrowing experiment were the last 50 years in Florida (Kautz, 1993) and approx- moist, and because no toadlets attempted to burrow imately three million people relocating to the state per in any saturated substrate, we only compared the dry decade of Economic and (Bureau Business Research, and moist substrates in the toadlet preference exper- force us to characteristics of ur- 1998) identify specific iment. It is possible that two substrates with identical ban that anuran declines. developments precipitate water content will present very different moisture ten- Anurans seem particularly susceptible to urbani- sion to the toads. We tested the soil moisture tension zation because of their life an- biphasic history. Many for the sand and soil mixture by the ceramic plate uran depend upon uplands, which often are extraction method (Slatyer, 1967), providing a mea- located away from the aquatic habitats used for repro- sure of the soil matric potential (sensu Kramer et al., duction (e.g., Pearson, 1955; Dodd and Cade, 1998). 1966). Over the range of experimental moistures, the Because urbanization in Florida often severely alters moist sand and soil mixture substrates had similar terrestrial habitats, the biological requirements of res- water (see box in so soil moisture ident species may be degraded enough to reduce pop- potentials Fig. 1), was not a factor in the toadlet preference trials. Adult BurrowingExperiment.-Adult toads were cap- ' Corresponding Author/Present Address: Depart- tured during the rainy season in Pine Flatwoods Wil- ment of Natural Sciences, University of Virginia's Col- derness Park, Hillsborough County, Florida. Twelve lege at Wise, Wise, Virginia 24293 USA; E-mail: individuals [>35 mm snout-urostyle length (SUL)] [email protected]. were housed separately in one-liter containers with 4 142 SHORTER COMMUNICATIONS

10 - 25?C. All toadlets were maintained in these aquaria unless engaged in a burrowing experiment. 9 Each testing arena consisted of a 20-liter aquarium (800 cm2 base) filled with two distinct treatment sub- A1 strates. Individual treatment substrates - A U occupied a equal halves of an aquarium and were 4 cm deep. The 5 7 -A-SAND surface of each substrate was flattened when neces- sary to reduce the possibility of instinctive burrowing .0 -r- SOIL ,-o near perceived crevices (Creusere and Whitford, 1976; 6 - A U Weintraub, 1980) and/or conspecifics (Creusere and Whitford, 1976). To examine whether juvenile S. h. hol- 1 52 brookiiselected substrates based on moisture content, we gave them a choice of dry sand or moist soil in I 4 one testing arena and wet sand or dry soil in another arena. Toadlets were also given a choice between dry sand and soil to see whether there was a 3 dry prefer- ence in the absence of adequate moisture. After several trials, it was clear that toadlets preferred moist sub- A - ? 2 I I I strates. A fourth choice, between wet gravel and dry \, sand was used to determine the strength of this pref- 1 M-A erence. Two testing arenas with a single uniform sub- strate (one with moist sand and one with moist soil) 0 were used to control for possible side bias. each substrate 0 1 2 3 4 5 6 7 8 9 Five trials were performed for pair. A trial consisted of placing 20 individuals haphazard- SubstrateWater Content (% wt) ly chosen from the pool of approximately 100 at the FIG.1. Moisture tension curves for substrate sam- juncture of the two substrates. Trials ran 24 h, and ples used in the burrowing preference experiments. then the substrate was carefully searched with a blunt The box represents values for treatment substrates probe to locate the burrowed toadlets. An individual used during trials. Tension curves were constructed "selected" a substrate if it was fully covered by the only for substrates used by juvenile Scaphiopushol- substrate or located in a cavity with more than half brookiiholbrookii. its body covered. Alternatively, an individual on the surface or with half or more of its body uncovered was considered "undecided" and was not used in subsequent calculations. A G-test with Williams' cm of damp sand, maintained at 23-25?C and fed (1976) correction factor was used for all burrowing crickets ad libitum. preference experiments to compare the observed dis- Trials were conducted in five-liter aquaria with 10 cm tribution of selected toadlets with the null hypothesis of substrate. Each of the 12 adult toads was randomly that burrowed individuals were equally distributed assigned a schedule of substrates and was given three between the treatment substrates. chances to burrow in each of the treatmentsubstrates. A Results of Adult BurrowingExperiment.-Adult toads trial consisted of gently transferringa toad into the bur- usually began burrowing within 15 sec of placement rowing aquarium and starting a timer when the toad in the test arena. Toads burrowed into the substrate began to burrow. When a toad had covered itself, it was rear first using their hind limbs. The burrowing mo- considered to have burrowed, and the elapsed time was tion was repetitive and stereotyped. With the hip, recorded. If a toad did not burrow within 10 min, the knee, and ankle joint fully flexed, the leg was drawn trial was terminated and scored as "did not burrow." up against the side of the body, at which time the Sod was the only substrate in which no toads burrowed, femur was rotated laterally, causing the foot to move so these trials were extended to 24 h. Because no toad from a ventral position to a lateral position. The ke- successfully burrowed in sod within 24 h, this substrate ratinous spade on the medial aspect of the foot as well was removed from subsequent data analysis concerning as the toes and associated webbing scraped substrate burrowing times. All successful burrowing attempts in from under the posterior part of the body and shov- the other three substrates took less than 5 min; however, eled it laterally and dorsally. The two legs were used each toad was tested on only one substrate in any 24-h alternately rather than simultaneously during this op- period. eration. In this manner, the toad excavated a burrow The fastest burrowing time in each substrate was while piling the removed material on top of itself, a used to rank the substrates from 1 (easy) to 3 (diffi- behavior that seems to explain the structuring of bur- cult) for each toad. If a toad did not burrow in a sub- rows previously reported by Ruibal et al. (1969) for strate, it was given the highest rank. A Pearson's rank Scaphiopus.The alternating pattern led to a rotation of correlation was used to detect an effect of substrate the toad during burrowing ranging from 0? to 720?. on burrowing success. There was no detectable handedness to this rotation ToadletPreference Experiment.-Toadlets were collect- (G = 1.364, df = 1, P = 0.24), nor did there appear to ed as they dispersed from the same temporary pool be a correlation with rotation and substrate type. where the adults were collected. Individuals (mean Adult toads burrowed in all substrates except St. SUL = 16.2 mm, SD = 1.1, N = 104) were kept in 25- Augustine sod. No toad penetrated the surface run- liter aquaria containing moist paper towels at 23- ning root system of this drought resistant grass. There SHORTEJ COMMUNICATIONS 143

TABLE 1. Burrowing times of adult Scaphiopushol- 25 brookii holbrookiiin three substrates. Mean and range values were calculated from the fastest of three at- tempts by each of 12 individuals. The fastest time for 20- each substrate determined the relative difficulty of burrowing in that substrate for an individual toad. Rank is the average difficulty among individuals for 15 - that substrate.

Substratetype Mean (s) Range (s) Rank 10 Sand 36 15-192 1.1 : 10 Soil mixture 51 34-77 1.9 Gravel 274 225-505 3.0 z

were detectable differences in burrowing ability among the other substrates (Table 1), with sand being the easiest in which to burrow and gravel the most SAND SOIL SAND GRAVEL SAND SOD difficult. SubstrateComparisons Results of Toadlet Preference Experiment.-Toadlets hopped around the test arena for several minutes to FIG.2. Influence of substrate type during burrow- several hours before burrowing. On many occasions a ing preference experiments with newly metamor- toadlet started burrowing then stopped but eventually phosed Scaphiopusholbrookii holbrookii. Substrates were resumed burrowing in another location. We do not maintained at 6-8% water content and sand was pre- know whether toadlets burrowed completely into the ferred over soil (G = 37.338, df = 1, P << 0.001), gravel substrate then abandoned the burrow within the 24 h (G = 124.06, df = 1, P << 0.001), and sod (G = 64.305, test period, although we never observed such an df = 1, P << 0.001). Bars represent one standard de- event. There was no detectable side bias because toad- viation. lets were distributed evenly throughout the test arenas containing a single uniform substrate (G = 0.708, df = 1, P = 0.40). preted as a preference for substrates that were me- When substrate moisture was relatively constant (6- chanically accessible for burrowing (Ruibal et al., 8%), significantly more toadlets burrowed in sand than 1969). If this hypothesis is correct, juvenile S. h. hol- in soil, gravel, or sod (Fig. 2). No individual burrowed brookii could be excluded from developed areas con- in gravel or sod when sand was an option (Fig. 2). When taining extensive sod and gravel. Toadlets did not bur- substrates that differed in moisture content were used, row in sod or moist gravel, even when the alternatives moist substrates were chosen significantly more often were to burrow in completely dry sand or remain on than dry ones (Fig. 3). Only 32% of toadlets burrowed the surface. Toadlets also remained on the surface when both treatment substrates were dry (Fig. 3), where- when confronted with water-saturated substrates, as 90% of toadlets burrowed during trials where moist which are typical of the humic soils bordering reten- sand or soil mixture substrates were available.When pre- tion ponds in urban developments. Given the low sented with a choice between moist gravel and dry sand, availability of suitable burrowing habitat, and the im- only 40% of toadlets burrowed, and no individual bur- portance of adequate soil moisture (Whitford and rowed in the moist gravel (Fig. 3). Meltzer, 1976) and subsurface daytime retreats (Creu- Discussion.-Adult spadefoot toads could not bur- sere and Whitford, 1976), toadlet survival likely is low row in grass sod, suggesting that developed areas pro- in such developed areas. vide fewer refugia in which toads can shelter. The The inability of adults to burrow in sod and toadlet drought-resistant grasses typical of Florida have a sys- avoidance of sod, gravel, and saturated substrates tem of stiff, springy surface roots that deform when jeopardizes populations of S. h. holbrookiiin several the toad burrows but snap back to their original po- ways. First, adults would be forced to find scattered sition as the foot scoops. Toads attempt to burrow sev- soil refugia within a developed site. Soils within de- eral times in sod before giving up. Although adult veloped areas may be contaminated from surface run- toads could burrow in gravel, it was difficult for them off (see Boyd and Gardiner, 1990) and landscape man- to do so. It took toads 7.6 times longer to burrow in agement practices, and anurans are susceptible to tox- gravel than in sand. We suggest that toads suffer ad- ins throughout ontogeny (Sanders, 1970; Judd, 1977; ditional energetic costs, increased exposure to preda- Beattie et al., 1991; Herkovits and Perez-Coll, 1991; tors, and risk injury when attempting to burrow in Pradham and Dasgupta, 1991). Second, newly trans- gravel instead of sand. Adult spadefoot toads bur- formed toadlets would have difficulty finding a place rowed most efficiently in sand. Consequently, if spa- to burrow and it is unlikely that they could remain defoot populations are to persist in urban develop- adequately hydrated during the day outside of refu- ments, sand must be available as a surface substrate gia. High mortality in a range of life-history stages of for burrowing. S. h. holbrookiimakes it difficult for populations to sur- Scaphiopusselected loose, friable soils for burrowing vive or become reestablished in urban areas. These in previous field experiments. This result was inter- circumstances also may isolate spadefoot populations. 144 SHORTERCOMMUNICATIONS

X 25 part by the Florida Fish and Wildlife Conservation Commission Wildlife and t2 20 Nongame Program (KPJ) the Helen Gaige Fund of the American Society of Ich- Z 15 .2 thyologists and Herpetologists (APS). Southwest Flor- ida Water Management District (specifically J. Hum- ble) granted access to Pine Flatwoods Wilderness o WETRYDRY ET DY-WT NS 5 Park. We thank R. E. H. I Altig, McCoy, Mushinsky, J. T. Streelman, and two anonymous reviewers for help- S O WET DRY DRY WET DRY WET DRY DRY ful comments on earlier drafts. SANDSOIL SANDSOIL SANDGRAVEL SAND SOIL LITERATURECITED Substrate Comparisons BEATTIE,R. C., R. J. ASHTON,AND A. G. P. MILNER. FIG.3. Influence of soil moisture during burrow- 1991. A field study of fertilization and embryonic preference experiments with newly metamor- ing development in the common frog Rana temporaria phosed Scaphiopusholbrookii holbrookii. Moist surfaces with particular reference to acidity and tempera- were preferred and overrode the toadlets' preference ture. J. Appl. Ecol. 28:346-357. for sand except when compared to gravel. Moist sand BOYD, G., AND N. GARDINER. 1990. Urban storm wa- was over soil = df = P preferred dry (G 74.023, 1, << ter: an overview for Public Works but sand was selected less often than municipalities. 0.001), dry moist 121:39-42. soil (G = 103.22, df = 1, P << 0.001). However, toadlets BRONMARK, C., AND P. EDENHAMN. 1994. Does the preferred dry sand to moist gravel = 48.199, df = (G presence of fish affect the distribution of tree frogs 1, P < 0.001). Toadlets did not show a preference (Hyla arborea)?Conserv. Biol. 8:841-845. when with sand and soil = presented dry dry (G BUREAU OF ECONOMIC AND BUSINESS RESEARCH. 1998. df = P = Bars one standard 1.114, 1, 0.29). represent Florida Statistical Abstract. Univ. Presses of Flori- deviation. da, Gainesville. BURKE,V. J., ANDJ. W. GIBBONS.1995. Terrestrialbuff- er zones and wetland conservation: a case of Because the risk of of anuran study extirpation populations freshwater turtles in a Carolina Conserv. Biol. increases with Bay. increasing fragmentation (Sjogren, 9:1365-1369. 1991; Vos and Stumpel, 1995), both established and COCHRANE,P. A. 1989. Historical changes in subur- founder populations in developed areas become more ban herpetofauna in Du Page County, Illinois. Bull. susceptible to extinction. Chicago Herpetol. Soc. 24:1-7. A recent study has suggested that the pervasive loss COLLINSON,N. H., J. BIGGS,A. CORFIELD,M. J. HOD- of natural habitats at the local scale is of a greater SON, D. WALKER,M. WHITFIELD,AND P. J. WIL- detriment to amphibian species than commonly ac- LIAMS. 1995. and an et al., Indeed, S. h. holbrookii Temporary permanent ponds: knowledged (Delis 1996). assessment of the effects of out on the con- from urban where critical habi- drying disappeared settings servation value of macroinvertebrate com- tats wetland and were or de- aquatic (both upland) destroyed munities. Biol. Conserv. 74:125-133. graded (Delis et al., 1996). Recent studies have focused CREUSERE, F. M., AND W. G. WHITFORD. 1976. Ecolog- on the value of temporary wetlands in maintaining ical relationships in a desert anuran community. vegetative (e.g., Kirkman et al., 1998), invertebrate Herpetologica 32:7-18. Collinson et al., 1995), and vertebrate Dodd, (e.g., (e.g., DELIS,P. R., H. R. MUSHINSKY,AND E. D. McCoY. as well as flood control and 1992) diversity providing 1996. Decline of some west-central Florida anuran water enhancement (Robinson, 1995). In ad- quality populations in to habitat degradation. dition, anuran on response many populations depend tempo- Biodiv. Conserv. 5:1579-1595. rary breeding pools Woodward, 1983; Bronmark (e.g., DODD JR., C. K. 1992. of a tem- and Edenhamn, wetlands are im- Biological diversity 1994). Temporary in north Florida san- and their continued is porary pond herpetofauna portant, legislated protection dhills. Biodiv. Conserv. 1:125-142. fully warranted. However, the surrounding "life DODD C. K., AND B. S. CADE. 1998. Movement zones" Semlitsch, do not have JR., (see 1998) currently and the conservation of similar patterns protection. in wetlands. Conserv. Like with life S. h. breeding small, temporary many organisms complex cycles, Biol. 12:331-339. holbrookii both wetland and upland habitat requires FAHRIG,L., J. H. PEDLAR,S. E. POPE,P. D. TAYLOR,AND (Burke and Gibbons, 1995; Samways and Steytler, J. F WEGNER.1995. Effect of road traffic on am- 1996; Dodd and Cade, 1998; Semlitsch, 1998). Spade- phibian density. Biol. Conserv. 73:177-182. foot toad populations need wetlands for reproduction HANSEN,K. L. 1958. Breeding pattern of the eastern and larval development and upland habitats for feed- spadefoot toad. Herpetologica 14:57-67. ing and burrowing. Conservation measures aimed at AND C. S. PEREZ-COLL. 1991. some minimum area of and terres- HERKOVITS,J., Antago- preserving aquatic nism and between lead and zinc in am- trial habitat are not sufficient for some the synergism organisms; larvae. Environ. Pollut. 69:217-222. characteristics of the habitat are also phibian physical impor- F. W. 1977. of monosodium metha- tant. Our data that char- JUDD, Toxicity suggest specific burrowing nearsonate herbicide to Couch's acteristics of the substrate need to be ad- spadefoot toad, upland may couchii. 33:44-46. dressed if toad are to in Scaphiopus Herpetologica spadefoot populations persist R. S. 1993. in urbanized KAUTZ, Trends Florida wildlife habitat landscapes. 1936-1987. Fla. Sci. 56:7-24. Acknowledgments.-This research was supported in KIRKMAN,L. K., M. B. DREW,L. T. WEST,AND E. R. SHORTER COMMUNICATIONS 145

BLOOD. 1998. Ecotone characterization between Journalof Herpetology,Vol. 35, No. 1, pp. 145-148,2001 Copyright2001 Societyfor the Study of Amphibiansand Reptiles upland longleaf pine/wiregrass stands and sea- sonally-ponded isolated wetlands. Wetlands 18: 346-364. of the Life and KRAMER,P. J., E. B. KNIPLING, AND L. N. MILLER. 1966. Aspects History Ecology Terminology of cell-water relations. Science 153: of the Coal Skink, Eumeces anthracinus, 889-890. in Georgia MINTON, S. A. 1968. The fate of amphibian and rep- tiles in a suburban area. J. Herpetol. 2:113-116. PAUL E. HOTCHKIN AND CARLOS D. CAMP,1Department PEARSON, P. G. 1955. Population ecology of the spa- of Biology,Piedmont College, Demorest,Georgia 30535 defoot toad, h. holbrookii Ecol. Scaphiopus (Harlan). JEREMYL. MARSHALL, Departmentof Biology, University 25:233-267. Monogr. of Louisiana-Lafayette,Lafayette, Louisiana 70504 PRADHAM, P. K., AND S. DASGUPTA. 1991. Effects of dimethoate on acid and alkaline phosphatase ac- The coal Eumeces is a medium- tivity in some metabolically active tissues of male skink, anthracinus, sized snout-vent 65 toad Bufo melanostictus.Geobios 18:59-63. (maximum length approximately lizard that has a localized distribution in ROBINSON, A. 1995. Small and seasonal does not mm) highly the midwestern and eastern United States mean insignificant: why it's worth standing up for (Walley, It is encountered its tiny and temporary wetlands. J. Soil Water Con- 1998). uncommonly throughout serv. 1995:586-590. range (Mount, 1975; Collins, 1993; Trauth, 1994; Dun- dee and Rossman, 1996) and is listed as RUIBAL, R., L. TEVIS JR., AND V. ROIG. 1969. The ter- endangered, threatened, or a of concern in at least restrial ecology of the spadefoot toad Scaphiopus species special five states (Mitchell, 1994; Ramus, 1998). It is a hammondii.Copeia 1969:571-584. ground-dwelling form that has a strong affinity for SAMWAYS, M. J., AND N. S. STEYTLER.1996. Dragonfly mesic sites and often occurs near water (Collins, 1993; (Odonata) distribution patterns in urban and forest Mount, 1975; Trauth, 1994; Dundee and Rossman, landscapes, and recommendations for riparian 1996). Other than habitat, very little is known about management. Biol. Conserv. 78:279-288. the ecology of this secretive species. Most information SANDERS, H. 0. 1970. Pesticide toxicities to tadpoles on life history and activity patterns is in the form of of the western chorus Pseudacris triseriataand frog scattered anecdotal observations (e.g., Collins, 1974; Fowler's toad woodhousiifowleri. 1970: Bufo Copeia Mount, 1975; Irwin, 1982). The single exception is 246-251. Trauth's (1994) study of gonadal development in Ar- SEMLITSCH,R. D. 1998. Biological delineation of ter- kansas. restrial buffer zones for salaman- pond-breeding Although normally rare, the abundance of coal ders. Conserv. Biol. 12:1113-1119. skinks in a forested area in Habersham County, Geor- SJOGREN, P. 1991. Extinction and isolation gradients gia, afforded us the opportunity to investigate the in metapopulations: the case of the pool frog (Rana ecology of this relatively unstudied species. Our spe- lessonae). Biol. J. Linn. Soc. 42:135-147. cific objectives were to use nondestructive sampling SLATYER,R. 0. 1967. Plant-Water Relationships. Aca- to collect data on life history and activity patterns. demic Press, New York. The study site was an area approximately 5000 m2 VOS, C. C., AND J. P. CHARDON. 1998. Effects of habitat located on the southern side of Lake Demorest, Ha- fragmentation and road density on the distribution bersham County, Georgia. This area is north-facing pattern of the moor frog Rana arvalis. J. Appl. Ecol. with a gentle slope (< 15?) abutting a marshy swamp 35:44-56. on its northern edge. The area is covered by a largely VOS, C. C., AND A. H. P. STUMPEL. 1995. Comparison deciduous forest. The most common trees are, in de- of habitat-isolation parameters in relation to frag- creasing order of abundance, tulip poplar (Liriodendron mented distribution patterns in the tree frog (Hyla tulipifera), short-leaf pine (Pinus echinata), red maple arborea).Land. Ecol. 11:203-214. (Acer rubrum), dogwood (Cornusflorida), beech (Fagus WEINTRAUB, J. D. 1980. Selection of daytime retreats grandifolia),and southern red oak (Quercusfalcata). The by recently metamorphosed Scaphiopusmultiplica- area is bisected by a north-flowing swampy stream, tus. J. Herpetol. 14:83-84. whose associated bottoms are dominated by Chinese WHITFORD, W. G., AND K. H. MELTZER. 1976. Changes privet (Lugustrum sinense). Much of the forest floor is in 02 consumption, body water and lipid in bur- densely covered with English ivy (Hedera helix). The rowed desert juvenile anurans. Herpetologica 32: southern end terminates at a south-facing roadbank, 23-25. which is approximately 45? and has a substrate of WILLIAMS,D. A. 1976. Improved likelihood ratio tests mowed grass and exposed soil. for complete contingency tables. Biometrika 63:33-37. We captured lizards using a drift fence similar to WILSON, L. D., AND L. PORRAS. 1983. The Ecological that described by Gibbons and Semlitsch (1981). The Impact of Man on the South Florida Herpetofauna. fence was 25 cm high with regularly spaced (approx- Univ. Kans. Mus. Nat. Hist. Monogr. no. 9, imately 5-m intervals) bucket stations. Each bucket sta- Lawrence, Kansas. tion consisted of a pair of four-liter buckets, each of on the side of the fence WOODWARD,B. D. 1983. Predator-preyinteractions and which was placed opposite from the other. The of the fence breeding-pond use of temporary-pond species in a longest part (100 m) the roadbank 10 m inside desert anuran community. Ecology 64:1549-155. paralleled approximately

Accepted: 3 May 2000. 1 Corresponding Author.