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The first live photos of the canyon pygmy mole cricket, Ellipes monticolus Günther, are presented, with preliminary observations on the habitat and behavior of populations in the Chiricahua Mountains of southeastern Arizona. The species was previously known solely from the original description in 1977, which included only drawings of the structure of the genitalia and almost no natural history information. This paper provides the first look at this species' biology and provides a framework for future studies on Tridactylidae of the southwestern United States. [ABSTRACT FROM AUTHOR]

We examined the response of Arizona cypress (Hesperocyparis arizonica) to the 2011 Horseshoe Two Megafire in the Chiricahua Mountains, Arizona, USA. We documented cover type, fire severity, cypress mortality and seedling establishment in 60 plots. In plots subject to severe fire, most mature cypresses were killed, the canopy opened and seedlings established abundantly. These results were consistent across three canyons differing in topography and vegetation. Successful regeneration of Arizona cypress contrasts with low seedling establishment for pines in the same area after the Horseshoe Two Fire, a difference possibly explained by abundant serotinous seed production in cypress or its preference for riparian sites protected from extreme fire. Our results firmly establish Arizona cypress as a fire-sensitive but fire-embracing species that depends on stand-replacing fire for regeneration. Given the fire sensitivity of Arizona cypress, however, recent increases in the frequency of high-severity fires in the south-west USA could pose a threat to the long-term viability of this species by preventing individuals from reaching sexual maturity during fire intervals. This scenario, termed the 'interval squeeze', has been documented in tecate cypress (H. forbesii) in California. A drier future with more frequent wildfires could pose serious threats to all New World cypresses. Our research firmly establishes Arizona cypress as a fire-sensitive but fire-embracing tree species dependent on stand-replacing fires for regeneration. Given its fire sensitivity, however, recent increases in fire frequency in the south-west USA could threaten the viability of this species by preventing the tree from reaching maturity between fires. [ABSTRACT FROM AUTHOR]

Fire regimes have changed dramatically in most dry woodlands and forests of the American Southwest from frequent surface fires prior to Euro-American settlement, to fire suppression in the 20th century, to a current era characterized by large, higher-severity wildfires. The recent increase in fire activity and consequent changes in forest communities are key management concerns across the region. We use sampling from before and after the 1994 Rattlesnake and 2011 Horseshoe Two Wildfires in the Chiricahua Mountains to address the extent to which higher-severity fire is converting Madrean pine-oak forest to oak shrubland in the Sky Islands of Arizona. Plant communities changed from mixed pine-oak forest before the wildfires to oak shrublands and grasslands by 2016 where fires burned at high-severity. In those sites, nearly all stems were killed above ground, oaks regenerated vigorously, mainly by resprouting, and pines recruited at very low levels. These patterns were consistent after each fire and for up to 14 years after the Rattlesnake Fire. Across the Horseshoe Two Fire, seedling recruitment of pines and oaks declined with increasing fire-severity, but oak resprouting increased. Differential recruitment success of oaks over pines was amplified by their far greater juvenile height and more ramets per resprouting genet. Resprouting in Pinus leiophylla (Chihuahua pine) after top-kill was low, but sufficient to suggest that this behavior may maintain this species at low density after high-severity fire. The impact of fire depended on topography, as less exposed plots (e.g. in drainages) experienced lower-severity fire and less conversion to oak shrublands, suggesting that these sites provided refugia for species, such as pines, sensitive to high-severity fire. Low pine recruitment occurred in all plots, not only in sites subject to high-severity fire, suggesting that vegetation conversion may have been exacerbated by the extreme drought of the past two decades. Given the episodic nature of their regeneration, pine recovery is possible in the future, but projections call for intensification of aridity and fire activity in the Southwest, which could lead to continued transition of Madrean pine-oak forests to more fire- and drought-resilient communities dominated by oaks. The results of this study point to the need for protective vegetation management and restoration experiments targeting pines. [ABSTRACT FROM AUTHOR]

Flooding and erosion after wildfires present increasing hazard as climate warms, semi-arid lands become drier, population increases, and the urban interface encroaches farther into wildlands. We quantify post-wildfire erosion in a steep, initially unchannelized, 7.5 ha headwater catchment following the 2011 Horseshoe 2 Fire in the Chiricahua Mountains of southeastern Arizona. Using time-lapse cameras, rain gauges, and repeat surveys by terrestrial laser scanner, we quantify the response of a burned landscape to subsequent precipitation events. Repeat surveys provide detailed pre-and post-rainfall measurements of landscape form associated with a range of weather events. The first post-fire precipitation led to sediment delivery equivalent to 0.017 m of erosion from hillslopes and 0.12 m of erosion from colluvial hollows. Volumetrically, 69% of sediment yield was generated from hillslope erosion and 31% was generated from gully channel establishment in colluvial hollows. Processes on hillslopes included erosion by extensive shallow overland flow, formation of rills and gullies, and generation of sediment-laden flows and possibly debris flows. Subsequent smaller rain events caused ongoing hillslope erosion and local deposition and erosion in gullies. Winter freeze-thaw led to soil expansion, likely related to frost-heaving, causing a net centimeter-scale elevation increase across soil-mantled slopes. By characterizing landscape form, the properties of near-surface materials, and measuring both precipitation and landscape change, we can improve our empirical understanding of landscape response to environmental forcing. This detailed approach to studying landscape response to wildfires may be useful in the improvement of predictive models of flood, debris flow and sedimentation hazards used in post-wildfire response assessments and land management, and may help improve process-based models of landscape evolution. [ABSTRACT FROM AUTHOR]

In this article, the author reflects on the aspects of seed collection trips during the autumn season of 2012 in Arizona. He informs about his first visits to Chiricahua Mountains in Cochise County, Arizona. He highlights that during second trips his group visited to Lyman Lake State Park located in Apache County. He further informs about the collection of seeds from several plant species including Chamaecrista nictitans, Indigofera sphaerocarpa and Rumex hymenosepalus.

Human suppression of fire has resulted in altered species composition and dense forest stands across the western United States. Accumulation of understory shrubs makes forests vulnerable to catastrophic fire and can impact animal use, whereas fire prescription can ameliorate negative impacts of suppression. We used radiotelemetry to determine patterns of habitat use and survival of Mexican fox squirrels (Sciurus nayaritensis chiricahuae)i n fire-suppressed and fire-prescribed areas of the Chiricahua Mountains, Arizona. Core areas of squirrels within fire-suppressed areas were larger and contained more understory shrubs than core areas of squirrels in fire- prescribed areas. Shrub cover and canopy heterogeneity influenced core-area size and distance traveled, and squirrels that were depredated traveled farther than conspecifics that survived, but shrub cover and canopy heterogeneity were not directly associated with squirrel survival. Suppression-induced increases in understory vegetation might force squirrels to travel greater distances to meet energetic requirements and thereby increase predation risk. Retention of mature forested canyons and restoration of natural fire regimes will be important for the persistence of Mexican fox squirrels. [ABSTRACT FROM AUTHOR]

The population-level dynamics of maternally transmitted endosymbionts, including reproductive parasites, depends primarily on the fitness effects and transmission fidelity of these infections. Although experimental laboratory studies have shown that within-host endosymbiont density can affect both of these factors, the existence of such effects in natural populations has not yet been documented. Using quantitative PCR, we survey the density of male-killing Wolbachia in natural populations of Drosophila innubila females from the Chiricahua Mountains of Arizona. We find that there is substantial (20 000-fold) variation in Wolbachia density among wild flies and that within-host Wolbachia density is positively correlated with both the efficacy of male killing and maternal transmission fidelity. Mean Wolbachia density increases three- to five-fold from early to late in the season. This pattern suggests that Wolbachia density declines with fly age, a conclusion corroborated by a laboratory study of Wolbachia density as a function of age. Finally, we suggest three alternative hypotheses to account for the approximately lognormal distribution of Wolbachia density among wild flies. [ABSTRACT FROM AUTHOR]

We explored use of non-invasive track and camera surveys to provide baseline information on distribution, activity, and habitat associations of mammalian carnivores within the Chiricahua and Peloncillo mountains of southeastern Arizona. In total, track and camera stations recorded 241 and 149 detections, respectively, of carnivores and other vertebrates in both mountain ranges. In order of frequency of detections, we recorded gray foxes (112 track and camera detections), white-nosed coatis (33), large skunks (25), ringtails (13), domestic dogs (13), coyotes (9), cougars (7), bobcats (3), and western spotted skunks (2) in both the Chiricahua and Peloncillo mountains, and one American black bear was photographed in the Chiricahua mountains. Other vertebrates detected included cattle (12), deer (10), and a variety of small rodents (83), birds (33), lizards (22), and lagomorphs (12). The combination of track and camera data were effective at detecting a variety of species in a range of habitat types, and emphasized the importance of deciduous riparian habitat for carnivores as well as other vertebrates. [ABSTRACT FROM AUTHOR]

Drosophila innubila is a mushroom-feeding member of the quinaria group, found in the woodlands and forests of the ‘sky islands’ in Arizona and New Mexico and extending south into central Mexico. Here, we describe and characterize 30 polymorphic microsatellite loci from D. innubila collected in the Chiricahua Mountains in Arizona. The number of alleles ranged from three to 21, and observed heterozygosity ranged from 0.0513 to 0.9737. Six loci were putatively X-linked, six departed from Hardy–Weinberg equilibrium, seven had evidence of null alleles, and six showed evidence of linkage disequilibrium. These markers will be useful for examining population structure of D. innubila and its association with male-killing Wolbachia. [ABSTRACT FROM AUTHOR]

I examined song variation within and among 23 individual Buff-breasted Flycatchers (Empidonax fulvifrons) recorded in the Chiricahua and Huachuca mountains of Arizona in 1999. I recorded two distinct song types from each individual during intense pre-dawn singing. I used both spectrographic cross correlation (SPCC) of entire songs and discriminant function analysis (DFA) of temporal and frequency measurements to examine whether songs were individually distinctive, and whether songs differed between the two localities. Similarity values of pairs of songs from SPCC were significantly greater for within-male than for between-male comparisons for both song types. Mean similarity values for the two song types did not overlap between these comparison categories. Similarity values between songs of pairs of males from the same mountain range were not greater than for comparisons between pairs of males from different ranges. All temporal and frequency measures for both song types varied significantly more among than within individuals. DFA of principal component scores derived from these measures assigned 85% of Type 1 and 86% of Type 2 songs to the correct individual. Only three frequency variables measured from Type I songs differed significantly between birds from the two mountain ranges. DFA assigned only 61% of songs of either type to the correct mountain range, not significantly greater than expected by chance. Thus, both techniques demonstrate significant individual distinctiveness in songs of this species, and neither suggests any geographic structuring of song variation between the two mountain ranges. However, SPCC is considerably more efficient and has greater potential to assign unknown recordings to known individuals correctly, and to detect recordings of "new" individuals not included in the reference sample. [ABSTRACT FROM AUTHOR]

Ant communities often consist of many species with apparently similar niches. We present a mathematical model of the dominance-discovery trade-off, the trade-off between the abilities to find and to control resources, showing that it can in principle facilitate the coexistence of large numbers of species. Baiting studies of dominance and discovery abilities in an ant community from the Chiricahua Mountains of Arizona indicate that real communities fail to fit the assumptions of the simple model in several ways: (1) dominance depends on the size of the food resource; (2) for some ants, dominance depends on the presence or absence of specialist parasitoids; (3) pairwise dominance is not an all-or-nothing trait; and (4) a consistent negative relationship between pairwise differences in per capita discovery rates and dominance can be detected for only one bait type. Extended models incorporating these factors successfully predict the coexistence of five of the six most abundant members of this community but fail to accurately predict their relative abundances. Sensitivity analysis indicates that each complicating factor enhances the extent of coexistence. [ABSTRACT FROM AUTHOR]

Acorn woodpeckers (Melanerpes formicivorus) were studied during the summers of 1976 and 1977 in the Chiricahua Mountains of Arizona to determine the ecological correlates of variations in unit size, storage behavior, and home range. Unit size varied from two to five adults, acorn storage capacity varied from 0 to 5,000 individual holes per unit, and home range size varied from 5.2 to 51.2 ha. There was a consistent but nonsignificant trend for units inhabiting pine-oak woodland to be larger and to maintain more food storage holes than units in oak-juniper or oak woodland. Pine-oak woodland had the highest oak species number, density, and basal area of any community in the study area, and showed the least annual variation in percent of oaks producing acorns during the study. However, pine-oak woodland also had the lowest acorn productivity per hectare. More than four times as many oak trees produced acorns in 1977 than in 1976. Following the poor 1976 crop, unit home range size increased so that the mean number of oaks contained per home range size increased more than three and a half times in 1977. The number of woodpecker units containing nonbreeding adults decreased from 90% in 1976 to 20% in 1977. These data suggest that the size and reliability of acorn crops control the composition of acorn woodpecker social units. A comparison of acorn woodpecker population parameters in the Chiricahua Mountains and at the Hastings Reservation, California, was made, using data of MacRoberts and MacRoberts (1976). The California population was significantly more dense and maintained more storage trees and more individual storage holes per unit, but there was no evidence that more California units contained nonbreeding adults than did Chiricahua units. A model is presented that emphasizes the importance of acorn crop reliability as the major determinant of acorn woodpecker social organization (Fig. 2). Annual crop fluctuations affect the winter survival and dispersion of woodpecker units, and the density of the population in the following spring. Bad acorn years will result in decreased saturation of woodpecker nesting habitat by established groups. The model predicts a corresponding decrease in the frequency of units with helpers, as young adults take advantage of opportunities to breed on their own. Longer-term crop reliability determines the benefit-cost ratio for establishing and maintaining food storage facilities. The observed geographic variation in storage behavior between California and Arizona populations is suggested to reflect differences in the long-term return on investment in expensive storage facilities. [ABSTRACT FROM AUTHOR]

We report the first record of the rare carpenter ant ( Camponotus microps) from the states of Guanajuato and Querétaro, México. This species was previously known only from the type series from the Chiricahua Mountains of southeastern Arizona, USA. This species is a member of the picipes species complex, and can be easily separated from the similar common Camponotus festinatus, as well as other members of the complex, by the short antennal scapes. [ABSTRACT FROM AUTHOR]

Take a hike in the Chiricahua Mountains of southern Arizona, and a procession of white-nosed coatis trooping across the trail may be spotted. Ranging from South America into the southwestern United States, these nosy cousins of the raccoon feast on fruit and small animals. For more on the coati and over 400 other species, from bats to whales, scurry over to North American Mammals. The web site, web4.si.edu/mna, from the Smithsonian Institution melds graphics with the hallmarks of a traditional field guide, such as range maps, drawings, photos, and species descriptions.