Northern Michigan University NMU Commons Journal Articles 1990 Natural History Note: Crotalus Viridis Viridis (Prairie Rattlesnake). Predation. Brent Graves [email protected] Follow this and additional works at: http://commons.nmu.edu/facwork_journalarticles Recommended Citation Graves, Brent, "Natural History Note: Crotalus Viridis Viridis (Prairie Rattlesnake). Predation." (1990). Journal Articles. 308. http://commons.nmu.edu/facwork_journalarticles/308 This Journal Article is brought to you for free and open access by NMU Commons. It has been accepted for inclusion in Journal Articles by an authorized administrator of NMU Commons. For more information, please contact [email protected],[email protected]. More potential refuges seemed to be availa- food are fairly common, observations of prey year old) observed on 13 October 1988 in the ble to the second skink. In addition to the capture are rare, and consequently foraging Museo de Historia Natural, Facultad de Cien- large board near which I first saw it, yucca modes are poorly known (Siegal and Fitch cias Biologicas, Universidad Autonoma de and other terrestrial vegetation was available 1984, Oecologia 61:293-301). Nuevo Le6n, San Nicolas de los Garza, Nuevo a few meters up the gentle slope from the My observations were made on 3 January Leon, Mexico. The snakes were siblings and pond. In both cases, algae and other aquatic 1989 in Everglades National Park (Florida) at were housed in a 5 gallon covered container vegetation obscured my view into the water. the boardwalk in Mahogany Hammock. Habi- laterally perforated. The male had an SVL of Both times I felt around on the bottom of the tat was open mature subtropical hardwood 523 mm; CL = 38 mm; mass = 111.2 g, and the water but was unable to locate either skink, hammock. Filtered sunlight reached the female presented SVL = 435 mm; CL = 25 mm; and did not see either one return to land. ground in several spots in the area snakes mass = 101.3 g. The temperature in the con- were observed. Shade temperature on the tainer was 26° C. Copulation began at 0900 h Submitted by LAUREN J. LIVO, 1215 S. boardwalk at 1400 h was 27.4° C. and ended at 1726 h. The female shed before Osceola Street, Denver, CO 80219, USA • At 1346 h we heard a racer (ca. 100 cm SVL) copulation; the male shed after copulation. emerge from a cabbage palm 6 m W of the We suggest that ecdysis of the female stimu- elevated portion of the boardwalk. It foraged lated copulation in a manner similar to that UTA PALMERI (San Pedro Side-blotched ca. 17 m in 13 min over a slightly circuitous reported for adult snakes. In reptiles, preco- Lizard). CANNIBALISM. Cannibalism in path, passing under the boardwalk, and finally cious sexual behavior has only been observed iguanid lizards, which typically are insecti- investigating and disappearing into an ele- in turtles (Kramer 1987. Joint Ann. Meet. vorous or herbivorous, is infrequently re- vated cavity in a strangler fig at 1359. Veracruz, Mexico. Programs and Abstracts). ported (Polis 1981. Ann. Rev. Ecol. Syst. At 1401 h a slightly larger racer (ca. 105-110 We thank David Lazcano for providing 12:225-251; Polis & Myers 1985. J. Herpetol. cm SVL) emerged from an upturned stump information, and Ivan Parra and Lea An- 19:99-107), although in some populations it about 10 m S along the boardwalk from where dersen for criticism and suggestions. has been observed frequently (J. Stamps, the first snake disappeared. It basked briefly pers. comm). and then foraged 6 m S along the boardwalk. Submitted by MANUEL NEVARES, Facul- On 15 April 1987 we observed an incidence At 1412 the racer dashed forward after a tree- tad de Ciencias Biologicas, Universidad of cannibalism in the insular endemic iguanid frog. The frog jumped from the leaf litter to ca. Autonoma de Nuevo Le6n, San Nicolas de los Uta palmeri by an adult male (75 mm SVL) on 0.5 m up a treetrunk, and thence immediately Garza, Nuevo Le6n, Mexico, and ADRIAN a juvenile (ca. 40-50 mm SVL). We first ob- to leaves of an adjacent shrub. The racer QUIJADA-MASCARENAS, Escuela Superior served the adult carrying the limp body of the simultaneously turned from the treetrunk and de Ecologia, Centro de Estudios Superiores juvenile, biting it at the middle of the trunk. cleanly picked the frog from leaves ca. 0.7 m del Estado de Sonora (CESUES), Calle Ley The male then carried the body several m, off the ground. The snake moved immediately Federal del Trabajo, Col. Apolo. Hermosillo, disappearing under a rock for less than ten to a sunny patch and basked in a loose coil for Sonora, Mexico • sec. He was next seen biting the body by its 14 min (until 1429). It then foraged an addi- tional 6 m S, climbing into a palmetto and head and, after a few seconds, he began CROTALUS VIRIDIS VIRIDIS (Prairie Rat- onto the boardwalk. At 1439 it dashed down engulfment. His forelimbs were not used to tlesnake). PREDATION. Among viperids, the palmetto and seized another fleeing tree- assist in engulfing the body, but we observed mark-recapture studies have suggested that frog. Foraging resumed immediately, and the small, side-to-side head movements during survivorship of young snakes is low, however, snake vanished into a thicket at 1441. this period. little information is available concerning Both treefrogs were brown and ca. 2.5-3 cm The frequency of cannibalism in U. palmeri causes of such mortality. The following SVL, and thus were probably is unknown. Wilcox (1980. PhD Dissertation. Hyla squirella, observations concern prairie rattlesnakes which I have seen in this hammock. In both University of California, San Diego) observed that overwintered in a perennially occupied cases the frog was swallowed less than 5 sec an adult male carrying a dead juvenile, but hibernaculum in Coal Creek Canyon, Carbon after capture. The second frog managed to was unsure if subsequent ingestion occurred. County, Wyoming in the spring of 1986. emit a single squeak before being swallowed. We and our coworkers have conducted over These animals were captured as they I estimate that the foraging racers covered 31 3,000 man-hours of observation on U. palmeri emerged, transported to camp for SVL and linear meters in 25 minutes of movement during two-month field seasons in three dif- mass measurements as well as radio teleme- (1.24 m/min). Both crawled steadily while ferent years (not always the same months ter implants (X mass of telemeters = 3.4 g, darting the head side to side in arcs ca. 15 cm each year), and have seen only this one case range = 3.1 - 3.5 g), then returned to the den wide. They would occasionally stop to inves- of cannibalism. However, only the 1987 field site for release. tigate an area more extensively, probing season coincided with a period when hatch- On 27 May at 1130 h a 14.9 g, 28 cm snake quickly into the leaf litter or investigating a lings and very small juveniles were abun- which had a transmitter implanted surgically log or stump. No rapid movements were seen dant on the study grids. on 7 May was found dead and being eaten by except the two strikes at prey. U. palmeri is substantially larger in body many ants (Formica spp.). It had moved 57 m Over 40 people walked within 2-4 m of the size than other Uta (Ballinger and Tinkle south between 2045 h on 25 May and 1620 h two snakes from 1346-1441, and two walked 1972. Misc. Pub. Mus. Zool. Univ. Mich. 145:1- on 26 May. On 28 May at 2000 h a 14.0 g, 27 cm past while the second snake was on the 83) with adult male body size ranging from snake which had a transmitter implanted sur- boardwalk. Neither species responded visibly 70-80 mm SVL (Hews, unpublished data). gically on 3 May was found dead and being to the other. The snakes seemed conditioned Hatchling size ranges from 27-32 mm (N=7) eaten by Formica. This snake had moved 35 to ignore the steady human traffic, allowing (Hews, unpublished data) and thus a large m east between 1415 and 2000 h on 28 May. us to make these observations. disparity in size between adults and small On 30 May at 1700 h an 18.2 g, 30 cm snake juveniles might facilitate cannibalism in U. that had a transmitter implanted surgically on Submitted by PHILIP C. ROSEN, Depart- palmeri. 28 May was found with its transmitter wedged ment of Ecology and Evolutionary Biology, Submitted by DIANA K. HEWS, Depart- between a rock and a sagebrush. Many For- University of Arizona, Tucson, AZ 85721, ment of Zoology, The University of Texas at mica were on the snake and biting it, and USA • Austin, Austin, TX 78712, USA and JEFFREY there was a column of ants traveling between C. DICKHAUT, 3822 Hope Lane, Erlanger, KY the snake and an ant mound. The snake was 41018, USA • alive, although it responded very sluggishly CROTALUS SCUTULATUS SCUTULATUS. to tactile stimuli. The snake had moved 36 m (Mojave Rattlesnake). MATING BEHAVIOR. southeast between 1000 h on 30 May (when it SERPENTES We have seen references to the minimum was released) and the time of the above length of the gravid rattlesnake (Klauber, observation. Many ants clinging to it by their COLUBER CONSTRICTOR PALUDICOLA L.M. 1972. Rattlesnakes. Univ. Calif. Press, mandibles were removed manually and the (Everglades Racer). FORAGING. Two adult pp. 175-176). However, we have no know- snake was returned to camp where it died racers were observed employing widely search- ledge of reports that indicate the minimum during the night.