Increasingly, endangered vertebrate species are being maintained in captive breeding programs as a method of ensuring their survival. Despite these increasing numbers of captive breeding colonies, there have been few studies designed to examine the long-term success of these programs at maintaining genetic diversity. To elucidate the effectiveness of a captive breeding colony of the endangered species Sauromalus varius (the San Esteban Chuckwalla) at maintaining genetic variation over time, we employed seven polymorphic microsatellite loci. F-statistics and analysis of molecular variance strongly suggest that the colony is exhibiting genetic signs of inbreeding. Genetic variation within the colony has decreased by an average of 12.2% within the colony between the 2 y sampled with an average loss of 30.5% of genetic variation within offspring. This study provides an important test of the effectiveness of captive breeding colonies at maintaining genetic variation within a vertebrate group over time.

The American beaver (Castor canadensis) has been promoted as a tool for restoring aquatic and riparian ecosystems in Western North America. However, little is known about the ecology of beavers in arid environments. The purpose of this study was to examine selection of habitat and woody forage species during winter along the Rio Grande in southern New Mexico. We compared habitat characteristics at sites where beavers were present and absent and evaluated forage selection of woody plants at presence sites. Beavers occurred at sites that retained water over winter and that had larger pools, higher cover of sedges (Cyperaceae), higher abundance of narrowleaf willow (Salix exigua) stems, and higher diversity of woody stems. For foraging, beavers strongly selected Rio Grande cottonwood (Populus deltoides) and Russian olive (Elaeagnus angustifolia) and used willows slightly more than available proportionately. We concluded that, while cottonwoods might require protection from beaver foraging, beavers were not having a negative impact on willows and did not promote saltcedars via ecological release.

We characterized the species richness, diversity, and distribution of amphibians and reptiles inhabiting El Monte Valley, a heavily disturbed, alluvium-filled basin within the lower San Diego River in Lakeside, California. This rare habitat type in coastal southern California is designated as a critical sand resource by the state of California and is currently under consideration for a large-scale sand mining operation with subsequent habitat restoration. We conducted field surveys from June 2015 to May 2016 using drift fence lines with funnel traps, coverboard arrays, walking transects, and road driving. We recorded 1,208 total captures, revealing high species richness and diversity, but with marked unevenness in species' abundances. Snakes were the most species-rich taxonomic group (13 species representing 11 genera), followed by lizards (11 species representing 9 genera). After the southern Pacific rattlesnake (Crotalus oreganus helleri), the California glossy snake (Arizona elegans occidentalis) was the second most frequently detected snake species (n = 23 captures). Amphibian species richness was limited to only three species in three genera. Despite the relatively limited 12-month sampling period, a longstanding drought, and severe habitat disturbance, our study demonstrates that El Monte Valley harbors a rich herpetofauna that includes many sensitive species.

Adult northern bobwhites (Colinus virginianus) are largely granivorous, primarily eating seeds produced from grasses and forbs. Our objective was to determine northern bobwhite preference among seeds of 45 plant species associated with sand sagebrush (Artemisia filifolia)–mixed prairie. A preference existed among the 45 plant species by weight of seed consumed and percentage of seed in diet (P ≤ 0.05) and on the basis of a cluster analysis of these variables. Five species were categorized into most preferred for food. These included, in order of preference: switchgrass (Panicum virgatum), Rocky Mountain bee plant (Peritoma serrulata), annual sunflower (Helianthus annuus), sand lovegrass (Eragrostis trichodes), and false sunflower (Heliopsis helianthoides). Thirteen plants were categorized into intermediately preferred for food, and 27 species were categorized into least preferred for food. The sand sagebrush–mixed prairie community supports a broad range of plants and animals. Improving rangeland conditions by employing conservative grazing management, especially during drought, or by planting a greater variety of native grasses, sunflowers, shrubs, forbs, and legumes, when reestablishing marginal crop lands, would improve the habitat and diet quality for northern bobwhite and other wildlife species.

In the Western Breeding Bird Survey Region, and in Colorado, breeding populations of the western wood-pewee (Contopus sordidulus) have decreased, and with global climate change their breeding range is predicted to decrease during this century. In addition, their breeding biology has not been commonly studied. From 1992–1998 and in 2001 and 2004, we studied the breeding biology and nest survival of this species in southwestern Colorado. During our study, timing of clutch initiation for the first seven nests within a breeding season advanced significantly earlier in the year from 14 June 1992 to 4 June 2004. Clutch size was typically three eggs that resulted in 2.48 (±0.08) fledglings from successful nests. Parasitism by brown-headed cowbirds (Molothrus ater) was infrequent with ∼5% of nests parasitized, but no parasitic young successfully fledged. Using Program MARK, the most-supported models to describe nest survival (n = 114 nests) in western wood-pewees used a varying daily survival rate during the breeding season along with some combination of the three covariates of year, the ratio of nest height to substrate (nest tree) height, and substrate (nest tree) height. Nest survival decreased with the breeding season. Also, nest concealment (determined in 1998, 2001, and 2004) was not significantly different between successful and unsuccessful nests of western wood-pewees.

We confirmed the breeding of the Common Yellowthroat (Geothlypis trichas) during 2008–2015 at Santa Ana National Wildlife Refuge and presented measurement evidence that individuals belong to the Brownsville Common Yellowthroat, Geothlypis trichas insperata. This expands the known breeding distribution for this rare and local subspecies.

Parasites were harvested from lungs and gastrointestinal tracts of Alligator mississippiensis from Texas. We compared our results with previous parasitism findings from alligators harvested in 2011 in Louisiana and Florida. Florida alligators exhibited the greatest pentastomid prevalence and mean intensity and illustrated higher stomach prevalence and intensity than other locations. Prevalence and mean intestinal parasitism of western Louisiana alligators differed significantly from other locations. Collectively, 14 species of trematodes and 7 species of nematodes were identified among Texas, Louisiana, and Florida. Differences in the parasite infracommunity structure across the alligators' geographic range likely reflects abiotic-biotic variation among the hosts' environment.

We report a previously unknown population of Poeciliopsis occidentalis occidentalis in La Barge Creek, a tributary stream to the Salt River in Arizona. The population inhabits a slick rock canyon with four permanent pools of water. Previous translocation efforts for P. o. occidentalis occurred more than 7 km upstream of the described location in Charlebois Spring; however, this species has not been observed at the translocation site recently. It is possible that the LaBarge Creek population emigrated from Charlebois Spring. Additional sampling is necessary to determine the source of this population.

The coccidian parasite Eimeria vilasi is reported for the first time from the round-tailed ground squirrel, Xerospermophilus tereticaudus. This coccidian was found in 9 of 94 (10%) round-tailed ground squirrels captured in Arizona. Sporulated oocysts were ovoidal, 20.1 × 18.1 (18–25 × 14–22) μm, with a length:width ratio of 1.1 (1.1–1.2). Sporocysts were ellipsoidal, 10.4 × 6.2 (8–13 × 5–7) μm, with a length:width ratio of 1.7 (1.3–2.2). The measurements and structural features of these oocysts were similar to those reported for E. vilasi from other marmotine rodents. Eimeria callospermophili was also recovered from 58 of 94 (62%) round-tailed ground squirrels.

The California vole, Microtus californicus, from the high-altitude meadows of the Sierra San Pedro Mártir, Baja California, Mexico had not been documented in 90 y and was thought to be extinct from this locality. In July of 2015, we documented an active, but reduced, population at one of its early collection sites. This population appears to be extremely restricted and should be protected and monitored.

Recent studies have identified an expanding range of Hemidactylus turcicus in southwestern Oklahoma. In 2015, researchers added nine additional Oklahoma county records to the known range of H. turcicus. Due to this new distribution, we conducted a statewide survey of Oklahoma for H. turcicus activity. We successfully identified 16 new county records for H. turcicus and 20 Oklahoma counties without H. turcicus activity.

Species geographic limits can be shaped by unfavorable conditions beyond range edges, and observations from peripheral habitats provide opportunities to assess individuals' capacity to tolerate environmental change. I monitored an extralimital breeding pair of Western burrowing owls (Athene cunicularia hypogea) in an eastern Kansas tallgrass prairie in 2013 using still and video photography. I quantified (1) the relative importance of different prey types in their diet, and (2) the timing and prevalence of a novel sunbathing behavior and discuss its possible adaptive significance. Owls in tallgrass prairie consumed more arthropods than vertebrates, with the latter contributing the most biomass in their diet. However, arthropods contributed more biomass than reported in studies that used indirect prey remains analyses. Owls sunbathed during midday when conditions were hot and dry, but never during cool periods or following rain events. I suggest owls in tallgrass prairie may sunbathe to shed ectoparasites.