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James M. Walker

Publications and source records attributed to James M. Walker.

3 recordsLinked to original sources
USGS2020

Body sizes in upper elevation populations of whiptail lizards: Aspidoscelis inornatus (Squamata: Teiidae) in central and northern Arizona, USA

The binational distribution of the gonochoristic (i.e., diploid bisexual) Aspidoscelis inornatus (Little Striped Whiptail) complex extends from parts of Arizona, New Mexico, and Texas in the USA (Taylor 1965; Stevens 1983; Wright and Lowe 1993; Sullivan 2009; Walker et al. 2012) southward into parts of the Mexican states Chihuahua, Coahuila, Durango, Nuevo León, Zacatecas, San Luis Potosí, and Tamaulipas (Axtell 1961; Wright and Lowe 1993; Farr et al. 2009; Walker et al. 2009). Within this vast distributional area, mean and maximum snout vent length (SVL) of A. inornatus varies geographically based in part on the types of habitats and climatic regimens occupied (Wright and Lowe 1993; Walker et al. 2009; Rosenblum and Harmon 2010).

Arizona↗
USGS2007

Distribution, habitat, size, and color pattern of Cnemidophorus lemniscatus (Sauria: Teiidae) on Cayo Cochino Pequeño, Honduras

Cayo Cochino Pequeño is a 0.64-km 2 Caribbean island in the Cayos Cochinos archipelago, Department of Islas de la Bahía, Honduras. One published report noted the presence of the rainbow whiptail ( Cnemidophorus lemniscatus ) on Cayo Cochino Pequeño, but nothing is known about the biology of this insular population. During a part of the dry season in July and August 2004, we used drift fences, pitfall traps, and separate observational transects to elucidate the distribution and habitat use of C. lemniscatus on the island. The only population of this species was located in a narrow coastal zone (width to 60 m and length to 450 m) on the southern half of the eastern windward side of the island. We analyzed the percentage of the canopy cover and the percentage of 4 ground coverage types along 2 transects 200 m long in this area to understand the basis of the suitability of the habitat for C. lemniscatus . Descriptively, the area harboring this species on Cayo Cochino Pequeño consisted of the remnants of a coconut palm grove with low-lying herbaceous vegetation and grasses, in which a mosaic of small, open areas of sandy soil and coral fragments, with or without accumulations of debris, were the foci of lizard activities. Also observed in this habitat were 2 individuals of the brown racer ( Dryadophis melanolomus ), an actively foraging snake and likely predator on C. lemniscatus . Data obtained on rainbow whiptails captured in pitfall traps and subsequently released were used to determine the size and color patterns of hatchlings and adult males and females.

Cayo Cochino Pequeno↗