Thamnophis marcianus (Checkered Gartersnake). USA: Arizona: Yuma and La Paz Counties: Colorado River
No abstract available.
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No abstract available.
Lithobates sylvaticus is the second most widely distributed anuran in North America (Martof and Humphries 1959. Am. Midl. Nat. 61:350–389), and its habitat use reflects the environmental variation that exists across its geographic range (Semlitsch et al. 2009. BioScience 59:853–862). Although L. sylvaticus post-breeding habitat selection has been described in Missouri (Rittenhouse and Semlitsch 2007. J. Herpetol. 41:645–653) and Maine (Baldwin et al. 2006. J. Herpetol. 40:442–453; Blomquist and Hunter 2010. Ecoscience 17:251–264), these studies did not report the species’ use of glacial erratics, or boulders. We conducted our study in Maine’s Nahmakanta Public Reserved Land (45.68210°N, 69.12940°W, WGS84; 407–530 m elev.), which is located in the Quebec/New England Boundary Mountains ecoregion.
No abstract available.
The globally widespread amphibian fungal pathogen Batrachochytrium dendrobatidis (Bd) has been linked to amphibian declines worldwide (Lips et al. 2006; Skerratt et al. 2007). In Louisiana, USA, Bd has been found in several amphibian species (Chatfield et al. 2012; Rothermel et al. 2008), but to our knowledge no population-level die-offs have been observed. Published literature on Bd prevalence in Louisiana is scant for some amphibian species and completely absent for many others. This trend is likely driven by the perception that Bd is not a major problem in this area due to a lack of observed dieoffs attributable to chytridiomycosis.
Thamnophis hammondii is considered one of the most aquatic of the gartersnakes and is closely associated with creeks and impoundments (Fitch 1940. Univ. California Publ. Zool. 44:1–150) with a diet consisting largely of both the larvae and transformed stages of amphibians (Spea, Bufo, Rana, Pseudacris) and small fish (Oncorhynchus, Gasterosteus, Eucyclogobius, and Cottus) (Jennings and Hayes 1994. Amphibian and Reptile Species of Special Concern in California. Final report contract no. 8023, California Department of Fish Game. 255 pp.; Rossman et al. 1996. The Garter Snakes: Evolution and Ecology. Univ. of Oklahoma Press, Norman. 332 pp.). Little is known regarding the foraging behavior of T. hammondii (Rossman et al., op. cit.). Herein, we describe the details of a predation sequence (approach, strike, and capture) observed in a natural setting.
We present observations of overwintering behavior in Taricha torosa torosa larvae at two independent sites. We define overwintering larvae as newts that spend the entire winter season in the larval form. The winter season (December, January, and February) represents the average three coldest months for the southern California coastal region (Felton 1965. California’s Many Climates. Pacific Books. 169 pp.).
American Alligators are opportunistic predators and their food habits have been well studied (Elsey et al. 1992. Proc. Annu. Conf. Southeast. Assoc. Fish Wildl. Agencies 46:57–66, and references therein and below). Composition of A. mississippiensis diet often varies due to regional limitation in prey availability (Neill 1971. The Last of the Ruling Reptiles. Alligators, Crocodiles, and their Kin. Columbia University Press, New York. 486 pp.; Gabrey 2010. Herpetol. Conserv. Biol. 5:241–250). Additionally, differential digestion rates can lead to over-representation of materials resistant to digestion or under-representation of rapidly digested soft-bodied prey items (Jackson et al. 1974. J. Herpetol. 8:378–381; Garnett 1985. J. Herpetol. 19:303–304; Delany and Abercrombie 1986. J. Wildl. Manage. 50:348–353; Platt et al. 1990. Northeast. Gulf Sci. 11:123–130). We herein report on a novel prey item for A. mississippiensis, which to our knowledge has not previously been reported.
No abstract available.
Commensalism is a relationship between two organisms whereby one benefits without negatively affecting the other. Like other horned lizards, Phyrnosoma hernandesi feeds primarily on ants, but will take other insects (Powell and Russell 1983. Can. J. Zool. 62:428–440). Here we describe apparent com-mensalism between P. hernandesi and Lark Buntings (Calamo-spiza melanocorys).
On 3 June 2015 at 1024 h, a team of U.S. Geological Survey scientists located an immature Gopherus agassizii (Agassiz’s desert tortoise) at Joshua Tree National Park, near the southern Cottonwood Canyon entrance. The habitat in the area is typical of the Sonoran Desert in that part of California with various trees and shrubs including Larrea tridentate (creosote bush), Parkinsonia florida (blue palo verde), Olneya tesota (ironwood), Fouquieria splendens (ocotillo) and Psorothamnus spinosus (smoketree), as well as numerous species of cacti, herbaceous plants and shrubs. The 89.4 mm in carapace length G. agassizii was estimated to be four years old by counting growth rings on the plastron, and weighed 160g. It was found basking on a flat spot on a north-facing, steep, rocky slope with a Ferocactus cylindraceus (California barrel cactus) spine impaling the G. agassizii under the right leg.
A variety of snake species employ head hiding as defensive behavior (Greene 1973. J. Herpetol. 7:143–161), but such behavior seems to be rarely observed in rattlesnakes. A recent report (Medica 2009. Herpetol. Rev. 40:95–97) presented observations on Crotalus scutulatus scutulatus and cited cases of similar behavior involving C. atrox , C. ruber , and C. viridis viridis . Here we report an encounter on 28 May 2016 with a C. oreganus lutosus (total length ca. 900 mm) observed 16 km S of Fallon, Churchill County, Nevada, USA. At 0925 h this snake was spotted by AKJ near the edge of the pavement on U.S. Hwy. 95. When approached, the snake presented typical active defensive behavior, with the rattle elevated (although not rattling), striking occasionally, and frequently flicking its conspicuous lavender and black tongue. As AKJ continued to take pictures the snake coiled more tightly (Fig. 1A), maintaining its rattle concealed and finally hiding its head beneath its coils (Fig. 1B). After photographing this pose AKJ made his first physical contact with the snake by scooping it up with a small shovel and placing it off the road. At this point the snake recovered its feisty attitude and would not retreat despite attempts to move it further away from the road. The snake did not rattle during the entire encounter (which lasted less than 5 min). Head hiding as a “last resort” in response to a persistent unavoidable threat may be more widespread within the family Crotalidae than previously documented.
Many species of snakes display arboreal behavior and are often found in vegetation many meters above ground. Mojave Desert snake species rarely get very far above the ground surface and are perhaps limited by predominantly low growing vegetation. Coluber flagellum piceus is considered strictly diurnal and although may ascend vegetation while active, is thought to retreat to subterranean refugia at night. Werler and Dixon (2000. Texas Snakes: Identification, Distribution, and Natural History. University of Texas Press, Austin. 437 pp.) stated “The western coachwhip is active above ground only during daylight hours. It almost invariably retires to depths of an animal burrow before sundown, where it spends the night.” The normal morning activity period for C. flagellum appears to be from approximately 0700–1000 h from June through September (Jones and Whitford 1989. Southwest. Nat. 34:460–467). Secor and Nagy (1994. Ecology 75:1600–1614), and Secor (1995. Herpetol. Monogr. 9:169–186) determined that the average body temperature for active above ground activity of C. flagellum was (33.1°C + 0.1°C, range of 24.0°C–40.8°C, N = 502), stating that coachwhip snakes were seldom active on the surface with body temperatures below 28°C. Here, I report a C. f. piceus that apparently spent the night draped in a Creosote Bush ( Larrea tridentata ).
No abstract available.