Several aspects of the ecology of coyotes (Canis latrans) have been studied in cities (i.e., diet, use and selection of habitat, movements), but additional knowledge will assist persons that are responsible for management of urban predators. We studied coyotes in central Tucson, Pima Co., Arizona, during November 2005–November 2006. Our objectives were to monitor radiocollared coyotes to determine size of home range, to ascertain use of habitat based on land-use categories and movements, and to describe a den of urban coyotes. Average size of home range calculated using the 95% fixed-kernel method was 26.8 ± 5.1 SE km² for resident coyotes. Overall, land categories used most often were washes, medium-density residential areas, and low-density residential areas. Movements were <520 m/h within land-use categories used most often during day and night (i.e., medium-density residential areas and washes) and >800 m/h in areas that were used most during the night (i.e., high-density residential and commercial areas). Coyotes were able to meet their life-history requirements in central Tucson likely due to available resources and a diversity of land-use categories, especially washes.

Assessing numerical response of northern bobwhites (Colinus virginianus) to habitat improvement in semi-arid rangeland often is confounded by responses of populations to highly variable patterns of rainfall. During 2 years of above-average rainfall, we investigated abundance of northern bobwhites relative to type of range and treatments to reduce brush on seven ranches in southern Texas. We expected response of populations to treatment of land to be more evident when northern bobwhites were released from constraints of low precipitation. However, main factors dominating abundance were rainfall during the previous growing season and type of range. Greatest numbers of calls were in mid-productivity rangeland (potential production of forage 2,000–3,900 kg/ha), especially sandy loam, clay loam, sandy, and gravelly ridge. Treatments to reduce brush increased abundance of northern bobwhites to a limited extent and were most effective when large blocks of land were treated. Techniques that kill brush (root-plowing) were more successful in increasing populations than top-removal methods (roller-chopping). Leaving strips or mottes (large clumps of living brush and trees) in cleared areas did not enhance populations, although we caution that retaining some brush cover may be important to survival of northern bobwhites in drier years and in situations where herbaceous cover is less abundant.

We studied 403 colonies of black-tailed prairie dogs (Cynomys ludovicianus) in a 28,927-km², 12-county area of the southern High Plains, and we examined the distribution, area of colonies, size of populations, and association of these colonies with playa lakes. We used visual counts and estimated size of populations based on modeling of the proportion of a population of prairie dogs above ground at the times of surveys. Colonies in the southern High Plains were small (median  =  8.8 ha), with generally small populations (median  =  68), and average densities of 14 ± 22 prairie dogs/ha. Colonies were closer to playa lakes than would be expected by chance (P < 0.001), with 40% of colonies built in the basin, slopes, or both, of playa lakes compared to only 3% of 1,000 random points. The association of prairie dogs with playa lakes in the heavily cultivated area of the southern High Plains suggests that playas are a major portion of the habitat of black-tailed prairie dogs in the region.

The calling song of the cicada Beameria venosa is a continuous train of sound pulses produced at a rate of 385 ± 29.5 pulses/s, with peak energy at 16.96 ± 1.76 kHz. The long-range sound field of B. venosa is symmetrical, but modified by interaction with vegetation and wind in the environment. High frequency of the call of B. venosa has a selective advantage with respect to avoidance of predators, permitting this cicada to be unnoticed by predators, principally birds and lizards, which cannot hear the call. As a result, the predation pressure on this cicada is decreased.

The New Mexico meadow jumping mouse (Zapus hudsonius luteus) is endemic to riparian habitats in the American Southwest. We evaluated current status and habitat of this species in the Jemez and Sacramento mountains, New Mexico. We compiled historical capture localities and conducted field surveys at historical and potential new localities during 2005 and 2006. We did not find the species or its habitat at 73% of historical localities surveyed in the Jemez Mountains and 94% of historical localities surveyed in the Sacramento Mountains. It persisted in two drainages (five localities) in the Jemez Mountains and two small, isolated localities in the Sacramento Mountains. Zapus h. luteus was associated with tall, dense, herbaceous riparian vegetation, especially areas dominated by sedges. The lower bound to the 95% confidence interval for vertical cover at localities where Z. h. luteus was captured was 63 cm. Decline in distribution was due to loss of this habitat, primarily as a result of livestock grazing. However, drought, development, recreation, forest fire, and loss of the American beaver (Castor canadensis) also contributed. We recommend that conservation of Z. h. luteus will require establishment of refugial areas of suitable habitat through protection from livestock grazing.

Sonoran pronghorns (Antilocapra americana sonoriensis) have been listed as endangered since 1967, yet relatively little is known about their behavior. Knowledge of behavior is essential to understanding their ecology, but these data are difficult to obtain for Sonoran pronghorns due to land-use restrictions and large, inaccessible range. However, with establishment of a semi-captive breeding facility (260 ha) for Sonoran pronghorns in southern Arizona, behavioral studies are feasible. We studied diurnal activity budgets of six adult female Sonoran pronghorns during January–December 2005 by recording behavior (i.e., foraging, bedding, standing, traveling, other) with instantaneous sampling at 2-min intervals. We observed pronghorns on 148 days during the year for a total of 49,035 observations. Pronghorns exhibited seasonal and diurnal differences in activity budgets. Behavior was constrained by temperature in spring and summer, and by availability of forage in autumn. These data are the first regarding detailed behavior of Sonoran pronghorns and are valuable to their management and conservation by providing more information on constraints faced by the subspecies.

The minimum length of stem required for production of flowers in the C₃ desert shrub ocotillo (Fouquieria splendens) has been widely accepted as 1 m since 1943. Long-term studies in the Chihuahuan Desert indicate that this threshold is no longer acceptable. During 2003–2006, 15 ocotillo stems shorter than 1 m produced 1–32 flowers each. The shortest stem on which flowers were produced was 62 cm long. Although fully capable of producing flowers, the contribution of stems <1 m long to overall production of flowers was small, accounting for only 0.49% of all flower-bearing stems. Stems <1 m long can no longer be excluded from studies of allocation to reproduction in ocotillo because of their assumed inability to produce flowers.

We studied effects of parasitism by brown-headed cowbirds (Molothrus ater) on three frequent hosts from a pinyon-juniper (Pinus-Juniperus) community in New Mexico. During 1993–1999 and 2001–2002, we measured frequencies of parasitism and examined how differences in size of host, life-history traits, and behavior, as well as aspects of behavior of brown-headed cowbirds (i.e., removal of eggs of host and multiple parasitism), influenced reproductive success of blue-gray gnatcatchers (Polioptila caerulea), plumbeous vireos (Vireo plumbeus), and western tanagers (Piranga ludoviciana). Brown-headed cowbirds parasitized 79% of 288 nests of blue-gray gnatcatchers, 84% of 170 nests of plumbeous vireos, and 76% of 129 nests of western tanagers. Parasitism reduced productivity of hosts through removal of eggs, reduced hatching success, reduced survival of nestlings, and desertion of nest. Relative to unparasitized nests, size of clutch of singly parasitized nests was reduced, on average, by 0.3 eggs for the plumbeous vireo and by 0.8 eggs for the two other species. Both blue-gray gnatcatchers and plumbeous vireos rarely fledged any of their own young from parasitized nests, whereas western tanagers did so regularly. All three species deserted some nests in association with parasitism, but the primary response to parasitism was acceptance of eggs from brown-headed cowbirds. Multiple parasitism was common, however, mean number of young of hosts that fledged only differed between singly and multiply parasitized nests for the western tanager due to high costs of single parasitism for the blue-gray gnatcatcher and plumbeous vireo. Overall, costs of parasitism were negatively correlated to body size of host; parasitism caused failure of 58% of nests of blue-gray gnatcatchers, 49% of nests of plumbeous vireos, and 22% of nests of western tanagers.

Much of the historic habitat of the red-billed pigeon (Patagioenas flavirostris) in southern Texas has been lost to agriculture, urban expansion, and changes in water flow in the Rio Grande. Populations in Texas have been declining since the 1920s. Our objectives were to quantify vegetational parameters in areas along the Rio Grande where red-billed pigeons were observed breeding and areas where they were not observed breeding. We conducted our study May–September, 2000 and 2001, along 30-km of the Rio Grande below Falcon Lake Dam in southern Texas. We used line-intercept transects to collect vegetational data in three areas where breeding activity was observed and in three areas where breeding activity was not observed. We compared length of transect, height of plants, width of canopy, density of plants, relative density of plants, and percent ground cover among and within areas. We also tested for relationships between height of trees and width of canopy. Height of trees and width of canopy were greater in breeding areas. The riparian zone was wider in breeding areas and there was greater heterogeneity in length of riparian zone within non-breeding areas. Breeding areas had high importance values for Mexican ash (Fraxinus berlandieriana), willow (Salix nigra), and Texas ebony (Pithocellobium ebano), and a low value for honey mesquite (Prosopis glandulosa). Mature stands of riparian habitat appeared to be favored by breeding red-billed pigeons. However, this habitat is declining along the Rio Grande and more information is needed to aid conservation efforts for this species in the United States.

We describe the first occurrence of the extinct dire wolf, Canis dirus, from the late Pleistocene deposits of east-central Sonora, Mexico. Remains include a partially complete left mandible and a left distal fragment of humerus collected from the deposits at Térapa. Local environments are interpreted to have been a tropical marsh with thorn-scrub to deciduous forest including some component of a nearby grassland. Although the mandible is nearer to the size of other large species of Canis known to occur in Mexico, the deep and robust mandible, presence of an accessory cuspid on the p2, an enlarged and robust p4, and accessory cuspids on the posterior margin of the trigonid ally the Canis from Térapa with C. dirus. Length of p4 suggests a possible closer affiliation to C. d. guildayi than to C. d. dirus.

We compared incidence and average size of melanistic, adult male Trachemys scripta among three populations in Oklahoma. Proportion and size of melanistic males differed among two uncontaminated sites and one site contaminated with heavy metals. Average size of melanistic animals collected from one locality were larger than melanistic animals collected at the same locality 50 years ago; however, minimum size of melanistic males at all sites was consistent with published values for populations of T. scripta throughout its range. The proportion of melanistic males among the three sites differed significantly and the smallest proportion of melanistic males was in a population of T. scripta from Tar Creek Superfund Site, Ottawa Co., Oklahoma, an area contaminated with heavy metals.

An American kestrel and barn owl were captured and eaten by red-tailed hawks during two separate encounters on San Clemente Island, California. There are few reports in the literature documenting red-tailed hawks taking other raptors as food items. These depredation events are likely rare, with one occurrence caused by human disturbance.

The northern pygmy mouse (Baiomys taylori), fulvous harvest mouse (Reithrodontomys fulvescens), and Merriam's pocket mouse (Perognathus merriami) are new to the diet of the western burrowing owl (Athene cunicularia hypugaea). All three species were identified from remains in regurgitated pellets collected from roost sites of burrowing owls in southern Texas over a period of 4 winters. Together, northern pygmy mice and fulvous harvest mice represented 58% of mammals identified in 182 pellets regurgitated by western burrowing owls. Merriam's pocket mouse accounted for only 4% of identified mammalian prey. Frequency of occurrence in pellets was 16% for northern pygmy mice, 11% for fulvous harvest mice, and 3% for Merriam's pocket mice. The primary reason for absence of these species in previous studies of foods of western burrowing owls is that most were conducted in latitudes north of these southern-distributed species of mammals.

Breeding birds of riparian forests and other habitats in the Ciudad Victoria area were studied, mainly in June 2003 and 2006. Olivaceous woodcreeper (Sittasomus griseicapillus), mangrove swallow (Tachycineta albilinea), and scrub euphonia (Euphonia affinis; nesting) extended their range north to the Ciudad Victoria area. Western kingbird (Tyrannus verticalis) nested for the first time in Tamaulipas and occurred south to the Ciudad Victoria area, and European starlings (Sturnus vulgaris) nested in south-central Tamaulipas for the first time. Great curassow (Crax rubra) and crested guan (Penelope purpurascens) were rediscovered in the Ciudad Victoria area for the first time since 1909. Distributions of many species in the state of Tamaulipas are changing, as tropical species move north and temperate-zone species move south.

Playas represent the only natural source of above-ground freshwater in the southern High Plains of North America; there are >20,000 such wetlands in the Panhandle of Texas (area of the highest concentration of playas). Many organisms use these small, ephemeral ponds during some stage of their life histories; e.g., dragonflies and damselflies (class Insecta, order Odonata, and suborders Anisoptera and Zygoptera, respectively) of this otherwise semi-arid region require these aquatic habitats for larval development. Relatively few distributional records have been established for Odonata in this region, so we conducted a baseline survey to assess distributional patterns of odonates in playas. Five seasons of observation and collection yielded important presence-absence data, resulting in 110 county records for the 16 counties in the study area.

We presented a new trap for pocket gophers and compared its effectiveness with the Baker and Williams live trap. Our box trap readily captured juveniles ≥44 g and adults ≤294 g. We had ≤50% capture success. In general, capture success was similar to the Baker and Williams live trap. However, analyses suggested that our trap was superior in some aspects, e.g., capture of heavier pocket gophers and males. Our trap was user friendly and could be employed to equally capture all portions of a population of pocket gophers.

Diet of the barn owl (Tyto alba) has been well studied in temperate regions of the world, but there is a notable paucity of dietary data from the Neotropics. In this study, we examined diet of barn owls at Gold Button Lagoon in northern Belize. Pellets and prey remains were collected at roosting sites during 1997–1998. Diet was composed primarily of small mammals. Sigmodon hispidus was the most common prey in terms of frequency of occurrence and biomass, with lesser numbers of other rodents being consumed. Similar to other reports for the Neotropics, barn owls in our study consumed relatively larger prey than conspecifics inhabiting temperate regions. Birds and amphibians were a minor component of diet.

In the spring of 1848, Phillip G. Ferguson wrote in his diary of having seen a number of “small fishes…many of them having glittering blue backs” in a warm spring a short distance south of El Carrizal in northern Chihuahua, for what we presume to be the first record of pupfishes (Cyprinodon) in that state or perhaps anywhere in Mexico. Here we discuss this, other 19^th-century, and subsequent occurrences of the genus in that region of North America, including our views on the species that Ferguson may have encountered, the scarcity of historical records of these fishes in Chihuahua, and possible reasons for the latter situation.