Short Term Movements of the Snakes Chironius Carinatus, Helicops Angulatus and Bothrops Atrox in Amazonian Peru Author(S): Robert W
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Herpetologists' League Short Term Movements of the Snakes Chironius carinatus, Helicops angulatus and Bothrops atrox in Amazonian Peru Author(s): Robert W. Henderson, Max A. Nickerson and Sherman Ketcham Source: Herpetologica, Vol. 32, No. 3 (Sep., 1976), pp. 304-310 Published by: Herpetologists' League Stable URL: http://www.jstor.org/stable/3891457 . Accessed: 23/08/2013 11:07 Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at . http://www.jstor.org/page/info/about/policies/terms.jsp . JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact [email protected]. Herpetologists' League is collaborating with JSTOR to digitize, preserve and extend access to Herpetologica. http://www.jstor.org This content downloaded from 128.227.142.231 on Fri, 23 Aug 2013 11:07:36 AM All use subject to JSTOR Terms and Conditions 304 HERPETOLOGICA [Vol. 32, No. 3 STOCK, C. 1930. Quaternary antelope remains WELLS, P. V. 1966. Late Pleistocene vegetation from a second cave in the Organ Mountains, and degree of pluvial change in the Chihuahuan New Mexico. Los Angeles Cty. Mus. Publ. 2: Desert. Science 153:970-975. 1-18. WILLIAMS, E. E. 1950. Testudo cubensis and 1932. A further study of the Quater- the evolution of western hemisphere tortoises. nary antelopes of Shelter Cave, New Mexico. Bull. Am. Mus. Nat. Hist. 95:1-36. Los Angeles Cty. Mus. Publ. 3:1-45. WOODBURY, A. M., AND R. HARDY. 1948. Studies VAN DEVENDER, T. R., W. G. SPAULDING, AND of the desert tortoise, Gopherus agassizi. Ecol. A. M. PHILLIPS,III. In press. Late Pleistocene Monogr. 18:145-200. plant communities in the Guadalupe Mountains, Culberson County, Texas. Symposium volume Received: 23 May 1975 on biological investigations in the Guadalupe Accepted: 22 August 1975 Mountains National Park, Texas. U.S. National Park Service, Washington, D. C. (TRVD and KBM) Departmentof Geo- WEBB, S. D. 1974. Pleistocene llamas of Flor- sciences, University of Arizona, Tucson, ida, with a brief review of the Ilami, p. 170- Arizona85721, and (AHH) Museum 213. In: S. D. Webb [ed.] Pleistocene mam- USA, mals of Florida. Univ. Florida Press, Gaines- of Arid Land Biology, Universityof Texas, ville. El Paso, Texas 77968, USA SHORT TERM MOVEMENTS OF THE SNAKES CHIRONIUS CARINATUS, HELICOPS ANGULATUS AND BOTHROPS ATROX IN AMAZONIAN PERU ROBERT W. HENDERSON, MAx A. NICKERSON AND SHERMAN KETCHAM ABSTRACT: Short term movements and habitat utilization of the colubrid snakes Chironius carinatus and Helicops angulatus and the viperid Bothrops atrox were studied using radiotelemetric methods in Amazonian Peru. The snakes were monitored for periods ranging from 50-111.5 h and the areas uti- lized by the snakes were 119.0 m' for C. carinatus, 29.1 m' for H. angulatus, and 43.0 m' for B. atrox. All three snakes moved in three dimensions. Chironius carinatus was diurnal and primarily arboreal and H. angulatus was nocturnal and highly aquatic. Bothrops atrox was nocturnal and at least young and subadult individuals are probably highly arboreal and might make daily vertical migra- tions between the ground and arboreal vegetation. Daily movements are comparable to those of some temperate zone species. Radiotelemetry appears to be a feasible means of studying the movements of rain forest snakes. LL1TLE is known about the movements, a degree that two individuals of the same activity range and habitat utilization in species may not be found for months. For Neotropical snakes. Information is avail- this reason the mark and recapture tech- able only for Boa constrictor (Henderson, nique used in most temperate studies on 1976), Leimadophis zweifeli (Test et snake movements is not feasible in the trop- al., 1966), and Oxybelis aeneus (Hender- ical rain forest habitat. son, 1974). Boa constrictor and 0. aeneus Using radiotelemetry we studied the were studied at mangrove edge in Belize movements of two colubrids (Chironius and L. zweifeli was studied in Venezuelan carinatus and Helicops angulatus) and one cloud forest. viperid (Bothrops atrox) in the Amazon Movements of Neotropical rain forest Basin of Peru. The goal of the project was snakes have not been previously studied. to determine the applicability of telemetry Rain forest snakes are found at low popula- to the study of rain forest snakes for future tion densities and/or are secretive to such studies over longer time periods. HERPETOLOGICA 32:304-310. September 1976 This content downloaded from 128.227.142.231 on Fri, 23 Aug 2013 11:07:36 AM All use subject to JSTOR Terms and Conditions September 1976] HERPETOLOGICA 305 MATERIALS AND METHODS lo Snakes' movements were studied with radiotelemetry equipment. Each snake was marked with a transmitter (Model SM1- Mouse style; AVM Instrument Co., Cham- paign, Ill.) with an internal antenna and which weighed 0.8 g. The transmitters broadcast in the 150 MHz range and each was equipped with a mercury battery (either an RM 575 or an MP 675). Both transmitter and battery were encapsulated with epoxy. Unfortunately, epoxy was not 2 = HIR-ONIUS CARINATUS N a satisfactory encapsulating substance, and FIG. 1.-Points at which the marked Chironius the' Chironius and Bothrops both appar- carinatus was radiolocated. Point 0 was the cap- ently digested the epoxy and the signals ture and release point, and radiolocation sites are numbered in chronological sequence. See the text from their transmitters were lost in a short for details. time. The transmitter and battery placed in the Helicops was coated with clear acrylic fingernail polish in addition to the ground on a bush in an aguajal swamp epoxy and the transmitter was still func- in disturbed closed canopy rain forest tioning after 4.5 days when it became dominated by the aguaje palm (Mauritia necessary to terminate the project. flexuosa). Aguajales always have stand- The transmitter-batte'rycapsule was lubri- ing water and become flooded after every cated with petroleum jelly and then force- rain (Dixon and Soini, 1975). Canopy was fed to the snake. A string was tied around broken allowing sunlight to penetrate and the snake's body immediately anterior to there were heavy tangles of undergrowth. the capsule to retard disgorgement of the Figure 1 shows points at which this snake capsule. After capsule placement snakes was radiolocated. On 2 November at 1325 were calmed by keeping them confined for h she was released where caught (Point at least 1 h before being released at the 0). She immediately moved down to the capture sites. ground and out of sight through the under- Signals were directionally received with growth headed southward. At 1550 h she a receiver (Model LA 12, AVM Inst. Co.) was located, but not seen, at Point 1, and a handheld, 3-element yagi antenna. 15 m from the release point and 2-3 m Signals were received from distance's of above the ground in a tangle of vegetation. 100-200 m depending upon the vertical lo- At 1900 h she was still at Point 1 and on cation of the snake. 3 November was located there three times Areas used by the snakes during track- between 0600 and 1600 h. A heavy rain ing were plotted on paper and were' mea- occurred between 0800 and 1130 h. At sured, as convex polygons, with a compen- 1515 h on 4 November she had crossed a sating polar planimeter. trail clearing on the ground and was lo- cate at Point 2. Chironius is diurnal and RESULTS the move was probably made sometime between daybreak and 1515 h. It was Chironiuscarinatus (Linnaeus) above ground in a mass of leaves, branches A female C. carinatus 90 cm snout-vent and vines. The sky was clear. On 5 No- length (SVL), was captured on 1 Novem- vember at 0845 h it was still at Point 2 and ber 1974 at 1300 h along a trail 1.0 km S the sky was overcast. On 6 November at of the village of Mishana on the' Rio Nanay, 0630 h the snake was located at Point 3 Loreto, Peru. The snake was 1 m above above the ground, probably at 2-3 m and This content downloaded from 128.227.142.231 on Fri, 23 Aug 2013 11:07:36 AM All use subject to JSTOR Terms and Conditions 306 HERPETOLOGICA [Vol. 32, No. 3 in the pond and the aquatic frog Pipa pipa was also taken there. The pond was regu- POND larly visited by humans for laundry, bath- ing, swimming and watering of livestock. The study animal, a female 31 cm SVL, was collected on 27 November at 1835 h GRASS (- 20 min after dark) within 1-2 m of a similar-sized H. angulatus and a H. poly- 9 * BUSHES lepis at the' pool edge close to aquatic vegetation. Only 5 min previously the \ 6 '. *22 " 1t4 snakes had not been there, and possibly .7 @ they had spent the day in the vegetation . 5 and had just moved into the pool when HELICOPS ANGULATUS found. Figure 2 shows points at which the snake FIG. 2.-Points at which the marked Helicops was radiolocated. It was released at the angulatus was radiolocated. Point 0 designates capture point (Point at 1610 h on the capture and release site, and radiolocation 0) 29 sites are numbered in chronologicalsequence. See November and immediately swam toward text for details. the aquatic grass along the "shelf" of the pond edge. It surfaced 1.5 m from Point 0 at the pond edge, remained motionless on the same side of the trail as Point 2 and for 2.0 min then subme'rged and swam 1 m from the trail.