Armando J. Contreras-Balderas

ERADICATION OF SPOTTED JEWELFISH, HEMICHROMIS GUTTATUS, FROM POZA SAN JOSÉ DEL ANTEOJO, CUATRO CIÉNEGAS BOLSÓN, COAHUILA, MEXICO

Abstract We report an apparently successful effort to restore native fishes to a pool in the Cuatro Ciénegas Bolsón, Coahuila, Mexico. The results demonstrate the feasibility, in small, confined systems, of eliminating a recently introduced nonnative fish, the spotted jewelfish (Hemichromis guttatus), and transplanting a native fish assemblage from nearby areas. We recommend that similar removal and restoration activities be conducted to protect the unique, highly endemic Cuatro Ciénegas fish fauna.

NICHE SEGREGATION WITHIN A DUNE LIZARD COMMUNITY IN COAHUILA, MEXICO

Abstract We studied niche segregation among 3 syntopic lizards, Uta stejnegeri, Uma exsul, and Aspidoscelis marmorata, in the sand dunes of Viesca, Coahuila, Mexico. In 2004, we analyzed both microhabitat and substrate niches during a warm season and a cold season. Niche breadth and overlap were calculated, and a selection index was used. Each lizard species selected microhabitats that focused on a single perennial plant species and a specific range of sand compactness. Uta stejnegeri was highly associated with the perennial Suaeda nigrescens and highly compacted sand. Uma exsul was associated with sites with deep, loosely compacted sand and Larrea tridentata. Aspidoscelis marmorata was associated with the occurrence of Prosopis glandulosa and moderately compacted sand. Associations described here could help to develop a future conservation and management program for these sand dunes, where the endemic U. exsul and other species are protected.

ADDITIONAL RECORDS OF BIRDS FROM CUATRO CIÉNEGAS BASIN, NATURAL PROTECTED AREA, COAHUILA, MEXICO

Abstract We recorded for the first time in Cuatro Cienegas Basin, Coahuila, Mexico, 43 species, 33 of them represented by specimens and 10 only by visual observations. These records increase the species known for the basin by 38.4%. The fieldwork was conducted during 1996 and 1997. Two species are new records for the state of Coahuila: Larus atricilla and Camptostoma imberbe.

MAMMALS OF THE CUATRO CIENEGAS BASIN, COAHUILA, MEXICO

Abstract The current (1996–1997 survey) mammalian fauna of the Cuatro Ciénegas Basin, Coahuila, Mexico, is compared with records of the past century as well as records from undated (pre-1953) owl-pellet records and undated (pre-1700) archaeological remains. The basin supports one of the largest freshwater areas in the deserts of northern Mexico and is located along the Sierra del Carmen–Sierra Madre Oriental Filter-Barrier, between the arid Chihuahuan and tropical Tamaulipan biotic provinces. The freshwater environment has remained remarkably stable through Pleistocene climatic oscillations, but more recently has been subjected to human-induced impact. Comparison of archaeological, historical, and current mammalian fauna depicts the well-known extirpation of larger carnivores and ungulates by humans; the shift to a drier, more Chihuahuan environment; and loss of species during the past century, including the apparent and unexplained disappearance of 4 species of rodents from the basin.

AGGREGATION OF SCELOPORUS MINOR (SAURIA: PHRYNOSOMATIDAE) FROM CERRO EL POTOSI, NUEVO LEON, MEXICO

Abstract We report for the first time aggregation behavior in the lizard Sceloporus minor. The behavior was recorded at Galeana, Nuevo León, Mexico, where a group of ca. 30 individuals were observed under a rock associated with a stone wall. Weight, sex, snout-vent length, and total length were recorded for 22 individuals. Means of traits were: males—weight  =  18.9 g, snout-vent length  =  80.5 mm, total length  =  173.3 mm; females—weight  =  13.9 g, snout-vent length  =  72.9 mm, total length  =  161.1 mm. Sex ratio was 16 males∶6 females. Our observation extends the known elevational range of the species from ca. 3,000 m to 3,470 m.

Red Crossbill (Loxia curvirostra) in Nuevo León, Mexico

Abstract This study documents the red crossbill (Loxia curvirostra) from the Cerro El Potosí region, Nuevo León, Mexico. Adults were observed at different sites and elevations in December 2006 and again in July and August 2007. A juvenile male was observed in August 2007. These multiple seasonal observations, as well as presence of a juvenile, indicate an established population in the area of Cerro El Potosí. This report adds the red crossbill to the list of permanent avian residents for Nuevo León.

VARIATION IN HOME RANGE OF THE SIDE-BLOTCHED LIZARD, UTA STEJNEGERI, IN COAHUILA, MEXICO

Abstract We studied seasonal variation in size and fidelity of home range in a population of eastern side-blotched lizards, Uta stejnegeri, in southern Coahuila, Mexico. Field work was carried out during the active seasons of 2002–2004. Home ranges during breeding and non-breeding seasons were larger for males than females and were reduced in both sexes during non-breeding months (autumn). There was greater intersexual overlap of home range during summer and less in autumn. Intrasexually, males had more overlap in home range than females (particularly during summer), which could be related to their large home ranges during that season. Fidelity to home range from one season to the next in a given year was similar in males and females. Although males had greater length and mass than females, neither measure correlated with size of home range. Density of adult lizards was negatively correlated with size of home range during the reproductive period. During non-reproductive months, density of all age classes combined was negatively correlated with size of home range. Our results indicate that home range sizes of U. stejnegeri vary considerably over the year and diverse factors are involved.

Herpetofauna of the Cerro El Potosi Natural Protected Area of Nuevo Leon, Mexico: Status of the Ecological and Altitudinal Distribution

ABSTRACT: Cerro El Potosi is a Natural Protected Area under State jurisdiction and it is one of the highest peaks of the Sierra Madre Oriental. It is an interesting area as its flora and fauna are distributed along a 2000–3750 m altitudinal gradient. The purpose of this study was to conduct an inventory of the herpetofauna and to describe its distribution in relation to plant communities and altitude. In addition, we address the risk of extirpation of some of the species. Twenty-five field trips of three to four days each were made between October 2006 and October 2008. A total of 268 individuals of amphibians and reptiles were observed. The sampled plant communities and number of herpetofaunal species found were: farming areas, eight species; submontane scrubland, four; chaparral, five; Quercus spp, six; Pinus pseudostrobus, eight; Pinus ayacahuite-, five; Pseudotsuga menziesii, five; Pinus hartwegii, five; Pinus strobiformis, two; Pinus culminicola, five; and catastrophic fire deforestation areas, three. According to the literature, 41 species are known from the area, while only 16 taxa were found during this study. The non-parametric estimators for species diversity indicated that the number of species tend to rise as sampling increases; the curve has not reached totality. Its asymptote represents 84.21% of herpetofauna for the mountain.

SECOND UNUSUAL RECORD OF COMMON LOON, GAVIA IMMER, FOR COAHUILA, MEXICO, AND ITS FIRST REPORT FOR THE CUATRO CIÉNEGAS BASIN

Abstract The common loon (Gavia immer) has occasionally been reported inland in northern Mexico. The first record in Coahuila, Mexico, was collected at El Tulillo reservoir in November 1986. The present record is more unusual, because it was collected on 12 June 2003, a late date for any location at this latitude. Damage caused by shotgun pellets to the ventral surface of both wings apparently prevented flight. This represents the second record for the state of Coahuila and the first record for the Cuatro Ciénegas Valley.

Black-Capped Vireo (Vireo atricapilla) in Urban Areas of Monterrey, Nuevo León, Mexico

Abstract We document breeding behavior of the endangered black-capped vireo (Vireo atricapilla) in urban areas of Monterrey, Nuevo León, Mexico. More surveys are needed to locate breeding populations in submontane scrublands near urban areas. Resumen Documentamos el comportamiento reproductivo del Vireo Gorra Negra en áreas urbanas de Monterrey en Nuevo León, México. Más muestreos son necesarios para localizar poblaciones anidantes en matorrales submontañosos cercanos a áreas urbanas.