Guadalupe Mountains National Park Research Articles

Restoring historical grasslands in a desert national park: Resilience or unrecoverable states in an emerging climate?

Ecosystems that supported multiple biological communities during the Holocene and that form alternative stable states pose challenges for identifying appropriate and feasible target communities for ecological restoration and conservation strategies for climate adaptation. In the Chihuahuan Desert, shrubland and perennial grassland alternatively dominated for millennia. However, grassland declined beginning 100–150 years ago during concomitant change in both climate and anthropogenic land use, making it unclear whether restoring grassland is appropriate or feasible in the emerging climate. In Guadalupe Mountains National Park, Texas, USA, we characterized remnant grasslands and performed experiments including outplanting and shrub reduction to assess feasibility and techniques for restoring desert grassland. In remnant patches, grass cover was more temporally variable than shrub cover, as grass cover varied 1.5× between years. Survival of outplanted grasses, either under Larrea tridentata shrubs or in the open with or without woody material encircling outplants for protection, was high (95 %) after seven months but declined to 2 % after 19 months. Response of perennial grass cover was variable after shrub and litter removal on soil surfaces varying in stoniness. Results suggest that 1) restoration can increase native desert grasses but gains may be intermittent; 2) reducing shrubs to facilitate natural expansion of remnant grasses and propagules may be more effective than outplanting grasses; and 3) restoring native grassland by reducing shrubs appears feasible even in dry conditions projected for the emerging climate. Findings that native grasses can increase at least intermittently suggest that practitioners have multiple candidate communities for conservation management and climate change adaptation as grassland, shrubland, and mixed communities each provide unique habitat.

Observations of the chemistry and concentrations of reactive Hg at locations with different ambient air chemistry

The Hg research community needs methods to more accurately measure atmospheric Hg concentrations and chemistry. The Reactive Mercury Active System (RMAS) uses cation exchange, nylon, and PTFE membranes to determine reactive mercury (RM), gaseous oxidized mercury, and particulate-bound mercury (PBM) concentrations and chemistry. New data for Atlanta, Georgia (NRGT) demonstrated that particulate-bound Hg was dominant and the chemistry was primarily N and S HgII compounds. At Great Salt Lake, Utah (GSL), RM was predominately PBM, with NS > organics > halogen > O HgII compounds. At Guadalupe Mountains National Park, Texas (GUMO), halogenated compound concentrations were lowest when air interacting with the site was primarily derived from the Midwest, and highest when the air was sourced from Mexico. At Amsterdam Island, Southern Indian Ocean, compounds were primarily halogenated with some N, S, and organic HgII compounds potentially associated with biological activity. The GEOS-Chem model was applied to see if it predicted measurements at five field sites. Model values were higher than observations at GSL, slightly lower at NRGT, and observations were an order of magnitude higher than modeled values for GUMO and Reno, Nevada. In general, data collected from 13 locations indicated that N, S, and organic RM compounds were associated with city and forest locations, halogenated compounds were sourced from the marine boundary layer, and O compounds were associated with long-range transport. Data being developed currently, and in the past, suggest there are multiple forms of RM that modelers must consider, and PBM is an important component of RM.

Low-Severity Wildfire Shifts Mixed Conifer Forests toward Historical Stand Structure in Guadalupe Mountains National Park, Texas, USA

Wildfire is an important natural disturbance agent, shaping mixed conifer forest structure throughout the Southwestern United States. Yet, fire exclusion caused by late 19th century livestock grazing followed by human fire suppression has altered forest structure by increasing forest density, basal area, and canopy cover in recent decades. Changes in the abundance and vertical and horizontal continuity of fuels have increased the potential for high-severity fire, which construes a major regional forest management concern. In May 2016, the Coyote Fire burned through a network of permanent forest monitoring plots in Guadalupe Mountains National Park. This study employed a repeated-measures sampling design to quantify the effects of low- to moderate-severity wildfire on forest stand structure, species composition, fuels, and tree mortality using hierarchical cluster analysis, non-metric multidimensional scaling (nMDS), and paired t-tests. The 2016 Coyote Fire reduced live tree density in small-diameter size classes, but produced minimal changes in canopy stand structure and fuel loadings, despite nearly a century of fire exclusion and pre-fire tree densities that were four-times higher they were prior to last major wildfire in the early 1900s. Small-diameter surface fuel loadings (1 h and 10 h fuels) did not significantly change after fire, although 1000 h fuels increased significantly (p < 0.05), likely from the addition of new fuel from fire-caused tree mortality. While the wildfire reduced live tree density, the nMDS analysis indicated that the wildfire did not trigger major shifts in tree species composition. However, the wildfire triggered significant decreases in seedlings and small-diameter trees (<30 cm DBH) (p < 0.05). Although the fire thinned the forest, the persistence of fuels and increases in dead small-diameter trees heighten the need for additional fuel reduction treatments to mitigate the risk of future high-severity fire under extreme fire weather. Management of low-severity fire in this forest type may provide opportunities to reduce fuels and restore more desirable stand structure to enhance forest resilience to landscape fire.

Guadalupe Mountains National Park: An Environmental History of the Southwest Borderlands

The story of American national parks has long consisted of layered histories of ecological changes, social collisions, forceful dispossessions, and persistent controversies over conservation and preservation. Many historians have carved out helpful environmental and public history narratives of parklands in the West. Scholars have recently moved beyond these approaches to consider parks as regional and global borderlands to understand new relationships and conflicts between the ecological, the political, and the personal. Jeffrey P. Shepherd joins this effort with Guadalupe Mountains National Park by tracing the ways many of these factors intersect in national park mountain lands that have long been borderlands for environmental, social, and political relationships. Shepherd argues that the history of the Guadalupe Mountains National Park helps us better understand the ways “people interact with their natural environments: how they perceive and misperceive them, try to control and transform them, and in this case, how they ultimately decide to live with and in them” (p. vii).

Progradational slope architecture and sediment distribution in outcrops of the mixed carbonate-siliciclastic Bone Spring Formation, Permian Basin, west Texas

AbstractSediment transport and distribution are the keys to understanding slope-building processes in mixed carbonate-siliciclastic sediment routing systems. The Permian Bone Spring Formation, Delaware Basin, west Texas, is such a mixed system and has been extensively studied in its distal (basinal) extent but is poorly constrained in its proximal upper-slope segment. Here, we define the stratigraphic architecture of proximal outcrops in Guadalupe Mountains National Park in order to delineate the shelf-slope dynamics of carbonate and siliciclastic sediment distribution and delivery to the basin. Upper-slope deposits are predominantly fine-grained carbonate lithologies, interbedded at various scales with terrigenous (i.e., siliciclastic and clay) hemipelagic and gravity-flow deposits. We identify ten slope-building clinothems varying from terrigenous-rich to carbonate-rich and truncated by slope detachment surfaces that record large-scale mass wasting of the shelf margin. X-ray fluorescence (XRF) data indicate that slope detachment surfaces contain elevated proportions of terrigenous sediment, suggesting that failure is triggered by changes in accommodation or sediment supply at the shelf margin. A well-exposed terrigenous-rich clinothem, identified here as the 1st Bone Spring Sand, provides evidence that carbonate and terrigenous sediments were deposited contemporaneously, suggesting that both autogenic and allogenic processes influenced sediment accumulation. The mixing of lithologies at multiple scales and the prevalence of mass wasting acted as primary controls on the stacking patterns of terrigenous and carbonate lithologies of the Bone Spring Formation, not only on the shelf margin and upper slope, but also in the distal, basinal deposits of the Delaware Basin.

First Record and Diet of the Tri-Colored Bat (Perimyotis subflavus) from Guadalupe Mountains National Park and Culberson County, Texas

The tri-colored bat (Perimyotis subflavus) occurs throughout the eastern United States, from Canada to south Florida and westward to eastern New Mexico, central Colorado, and western Texas. In this study, we document the first record of P. subflavus for both Guadalupe Mountains National Park and Culberson County, Texas. Our record extends the range of P. subflavus into the Trans-Pecos region of Texas. We also examined the diet of this individual and observed that it consisted of Lepidoptera, Coleoptera, and Hemiptera. Our observations of the diet of P. subflavus correspond with results of previous studies from more eastern portions of the species' range.

Guadalupe Mountains National Park: An Environmental History of the Southwest Borderlands. By Jeffrey P. Shepherd

Guadalupe Mountains National Park: An Environmental History of the Southwest Borderlands. By Jeffrey P. Shepherd

Guadalupe Mountains National Park: An Environmental History of the Southwest Borderlands. By Jeffrey P. Shepherd. Amherst: University of Massachusetts Press, 2019. xii +227 pp. Illustrations, maps, notes, and index. Paper $29.95.

<i> Guadalupe Mountains National Park: An Environmental History of the Southwest Borderlands. </i> By Jeffrey P. Shepherd. Amherst: University of Massachusetts Press, 2019. xii +227 pp. Illustrations, maps, notes, and index. Paper $29.95.

High-precision U-Pb zircon age constraints on the Guadalupian in West Texas, USA

The Guadalupian Epoch was characterized by major changes in paleogeography, paleoclimate, and biodiversity. Yet, the paucity of precise and accurate radioisotopic dates from the Guadalupian stages in their type area, Guadalupe Mountains National Park in West Texas has rendered their calibration inadequate. In this study, we report high-precision U-Pb zircon geochronology by the CA-ID-TIMS method from three ash beds (2σ internal errors only) in the Rader Member of the Bell Canyon Formation at the Back Ridge Section (262.127 ± 0.097 Ma, MSWD = 0.89, n = 3), the lower Pinery Member of the Bell Canyon Formation at the Frijole Section (264.23 ± 0.13 Ma, MSWD = 0.89, n = 8) and the basal South Wells Member of the Cherry Canyon Formation at the Monolith Canyon Section (266.525 ± 0.078 Ma, MSWD = 0.62, n = 5). The Bayesian interpolation statistics method is used to establish an age-stratigraphy model that estimates the base of the Capitanian to be 264.28 ± 0.16 Ma, serving as the best age estimate for the Capitanian Stage at present. In addition, we review the existing geochronology from the Guadalupian Series in West Texas and seek to propose more precise temporal estimates of Guadalupian geological and biological events. These data constrain the high-frequency sequences of the Cherry Canyon and Bell Canyon formations in the Guadalupe Mountains National Park area. Accordingly, the base of the Wordian is estimated at 266.9 ± 0.4 Ma and the Illawarra geomagnetic polarity reversal in West Texas at 267.4 ± 0.4 Ma to 266.5 ± 0.3 Ma. The global end-Guadalupian extinction began in the conodont zone of Jinogondolella altudaensis above the base of the Reef Trail Member of the Bell Canyon Formation and might continue to the Clarkina postbitteri postbitteri Zone in the earliest Wuchiapingian. The conodonts display a rapid evolutionary rate during this interval. This constrains the biotic crisis from ca. 260 Ma to 259 Ma based on our conodont age estimation. The emplacement of the Emeishan Large Igneous Province (ELIP) in South China has been constrained to ca. 260 Ma to 257.4 Ma based on zircon U-Pb geochronology by the CA-ID-TIMS method, overlapping with the end-Guadalupian extinction, which provides support for the temporal relationship between them. Additionally, the ELIP persisted into the early Wuchiapingian and may have hampered ecosystem restoration during the post-extinction interval.

Guadalupe Mountains National Park: An Environmental History of the Southwest Borderlands by Jeffrey P. Shepherd

Reviewed by: Guadalupe Mountains National Park: An Environmental History of the Southwest Borderlands by Jeffrey P. Shepherd Glen Sample Ely Guadalupe Mountains National Park: An Environmental History of the Southwest Borderlands. By Jeffrey P. Shepherd. (Amherst: University of Massachusetts Press, 2019. Pp. 227. Notes, index.) Jeffrey Shepherd’s instructive environmental history is a valuable resource for anyone who wants to gain a deeper understanding of the Guadalupe Mountains, its fragile, arid ecosystem, and how humans have interacted with and impacted their environment over the millennia. Guadalupe Mountains National Park, located in Texas, is smaller than 90,000 acres. Confronted with such a limited geographical area, Shepherd frames his narrative within the larger context of the Southwest Borderlands. His focus is a zone bounded by Roswell, New Mexico, 135 miles to the north, the Pecos River, sixty-five miles to the east, and El Paso, Texas, 115 miles to the west and south. After introducing the geology, flora, and fauna of the Guadalupes, the author moves to the area’s first inhabitants, who lived here more than 10,000 years ago. Next are Spanish exploration and settlement of the region during the sixteenth and seventeenth centuries. Following the U.S.–Mexico War, the United States sent topographic engineers to explore the Trans-Pecos region, including the Guadalupe Mountains, home of the highest point in Texas. These explorations, combined with railroad surveys during the 1850s, greatly expanded the existing knowledge of the area’s geography, natural resources, and inhabitants. Shepherd’s discussion of the Mescalero Apaches, their cultural lifeways, and the U.S. Army’s military engagements with this tribe, is a highlight. By the 1880s, the Southern Pacific and Texas and Pacific railways spanned West Texas, spurring area development and settlement. Soon vast cattle herds were grazing regional grasslands, and farmers were irrigating crops from the Pecos River. Another of the book’s standout chapters features gritty profiles of early homesteaders and settlers, scrappy men and women who adapted to their stark, remote environs. In the 1920s and 1930s, a flurry of oil exploration transformed West Texas and southern New Mexico. Conservation of the region’s outstanding scenic and environmental assets came later than in other parts of the Southwest, finally gaining traction with the establishment of Guadalupe Mountains National Park in 1966. [End Page 463] In widening his lens to focus on a larger study area, however, Shepherd overlooks some of the more important environmental concerns closer to home in the Guadalupes. One issue is the significant degradation and desertification of area grasslands by livestock overgrazing. Another is water. For the past sixty years, agricultural concerns in Dell City, located on the west side of the park, have aggressively pumped the Bone Spring-Victorio Peak Aquifer. This has lowered the water table on average by thirty feet, drying up significant, historic water sources such as Crow Spring. In addition, the city of El Paso is actively buying up water rights in the region to ensure its continued growth. How will all of this affect the Guadalupes? Discussions of nearby oil boom towns such as Mentone and Orla are absent from Shepherd’s story, as are the current environmental impacts of the Permian shale boom on the Guadalupe Mountains, including area work camps, heavy truck traffic, and considerable nighttime light pollution from Orla. There are also big changes in land ownership. The park’s immediate neighbor to the south is Amazon founder Jeff Bezos, who owns 400,000 acres and has built a space-rocket launching port on the old Figure 2 Ranch and adjacent land. These points notwithstanding, Shepherd’s thoughtful and informative work of the Guadalupe Mountains is a welcome addition to the growing historiography on the Texas Trans-Pecos. Glen Sample Ely Grand Junction, Colorado Copyright © 2020 The Texas State Historical Association

Large-Scale Inflections in Slope Angle Below the Shelf Break: A First Order Control On the Stratigraphic Architecture of Carbonate Slopes: Cutoff Formation, Guadalupe Mountains National Park, West Texas, U.S.A.

Abstract A large-scale inflection (LSI) in the slope profile may develop as a carbonate platform is drowned and abandoned basinward of the active shelf break. The impact of LSIs on the sediment dispersal patterns and stratigraphic architecture of carbonate slopes remains understudied. Outcrops of the Lower–middle Permian Cutoff Formation in the Guadalupe Mountains National Park provide a good view of a mixed carbonate and siliciclastic slope system modified by an LSI during the accumulation of a 2–4 My composite sequence (Permian composite sequence 9, PCS9). Processes of channelization, bypass, and slope failure associated with the LSI contribute to the development of basin-restricted carbonate, shale, and sandstone strata which demonstrate apparent onlap to the relict platform. Correlation of high-frequency sequences between the slope and shelf-equivalent strata demonstrates that channels incising the relict platform LSI served as conduits for confined gravity flows and depocenters for organic-rich shale throughout the transgression and much of the ensuing highstand of PCS9. In the latest highstand regression, an increase in the production of carbonate mud by the active shelf system contributed to the complete filling of channels across the LSI and accumulation of carbonate mud-dominated mass-transport deposits basinward of the LSI. A critical review of previous studies reveals that LSIs are common in the geologic record, across multiple basins and time periods. LSIs that developed due to drowning of carbonate platforms demonstrate dimensions and stratal patterns comparable to the relict Leonardian platform. LSI development in the identified examples occurred in association with 1) the transgressive stages of 10–100 My (second order) sequences, 2) ocean anoxic events, or 3) times of concomitant sea-level rise and ocean anoxic events.

Using Genetic Analysis to Evaluate Hybridization as a Conservation Concern for the Threatened SpeciesQuercus hinckleyiC.H. Muller (Fagaceae)

Premise of research. Hybridization among oaks is well documented and is of special concern in conservation efforts directed toward threatened or endangered Quercus, species such as Quercus hinckleyi.Methodology. This study uses DNA microsatellite analysis to characterize hybridization between the threatened oak Q. hinckleyi C.H. Muller and two putative hybridizing species, Quercus pungens Liebmann and Quercus vaseyana Buckley. The two potential hybridizers were sampled at Guadalupe Mountains National Park (GUMO), approximately 320 km from the current range of Q. hinckleyi. Quercus pungens and two possible hybrids located in near proximity to the relict populations of Q. hinckleyi were also sampled.Pivotal results. Genetic variability was high in all three species, with mean number of alleles per locus ranging from 12.625 to 17.875, mean observed heterozygosity from 0.734 to 0.807, and mean expected heterozygosity from 0.851 to 0.869. Quercus hinckleyi is genetically differentiated from the putative hybrid...

A new shelf-to-basin timeline for the Middle Permian (Guadalupian) Capitan Depositional System, West Texas and Southeastern New Mexico, USA

The correlation of the Rader Limestone Member of the Bell Canyon Formation to its shelf equivalent has varied over the years. Some models have equated it with the Seven Rivers Formation, and others to the Yates Formation, or a position straddling both units. More recent workers have used sequence stratigraphic models to refine this shelf-to-basin correlation, placing the “lower” part of the Rader Limestone Member in the Y3 high frequency sequence within the Yates Formation. Despite the presence of bentonites in both the Rader Limestone Member and the Yates Formation, and the potential to add a numerical age datum to the sequence stratigraphic hierarchy, geochemical tephrochronologic techniques have not yet been applied to the deposits. To address these issues, apatite phenocryst trace element chemistry was determined by electron microprobe analysis for samples from three bentonites collected from outcrop localities in Guadalupe Mountains National Park and two from the Gulf PDB-04 research well. Results are interpreted to indicate a correlation between a bentonite 16.5m above the base of the Rader at Back Ridge in the Patterson Hills of Guadalupe Mountains National Park, and one at 1956ft core depth in the PDB-04 core. Careful examination of the gamma-ray log for the well indicates that the 1956ft interval is in the Y3 high frequency sequence of Osleger and Tinker (1999). Further refinement can be made to the third cycle set of this high frequency sequence. Determining whether the bentonite at Back Ridge is in the “lower” or “upper” part of the Rader Member will require additional work. This correlation links the primary reference section for the basal through middle Capitanian Stage being established at Back Ridge with the shelf defined sequence stratigraphic framework. The sample from the Rader is the focus of U-Pb radioisotopic dating (Nicklen et al. in preparation) and would provide the first shelf-to-basin absolute age datum for the Capitan depositional system.

Tephrochronology of the Manzanita Limestone in the Middle Permian (Guadalupian) Type Area, West Texas and southeastern New Mexico, USA

Despite being recognized for many years, bentonites in the Guadalupian (Middle Permian Series) type area of West Texas and southeastern New Mexico have received little research attention. These important deposits offer opportunities for long distance stratigraphic correlation and high-precision radioisotopic age dating. In this study, apatite phenocryst chemistry is used to establish a tephrochronologic framework for the Manzanita Limestone Member of the Cherry Canyon Formation. Samples were collected from bentonites in one core and five field localities including Nipple Hill, which is the site of the Late Guadalupian (Capitanian Stage) GSSP and located in Guadalupe Mountains National Park. Apatite phenocrysts from these samples were analyzed for minor, trace, and rare earth element chemistry using electron microprobe techniques. Results indicate the presence of three patterns or trends of data that are repeated at multiple localities. These groups of data are interpreted to represent coeval deposits and are correlated among several localities to form a tephrochronologic framework. This framework links the strata on Nipple Hill with that of several other Guadalupian type area localities. Absolute age time control for the Guadalupian is poor, and the precise stratigraphic position of the existing radioisotopic date from Nipple Hill is uncertain. Based on a review of published reports and a new measured section of Nipple Hill presented herein, the most accurate position is in the Manzanita Member. That placement adjusts the only radioisotopic age constraint for the Capitanian GSSP lower in the Wordian Stage than previously reported. The bentonite correlations proposed herein constrain this position to the Mz-3 cycle of the Manzanita High Frequency Sequence and allow it to be traced to several outcrop localities, and across the Delaware Basin in the subsurface. Based on the correlation of a bentonite from its locus typicus near Casey’s Last Chance Well in Culberson County, Texas, the type specimen of the biostratigraphically significant ammonoid Newellites richardsoni is confirmed to have been recovered from the basal Manzanita Member (Wordian Stage), stratigraphically underlying the radioisotopic age date. The type locality of this ammonoid has been inconsistently reported in museum records and in the literature.

Assessing the feasibility for reintroducing desert bighorn sheep to Guadalupe Mountains National Park: Habitat, migration corridors and challenges

Desert bighorn sheep were once part of the Guadalupe Mountains ecosystem but were extirpated in the 1930s due to disease transmittance from domestic sheep and goats, habitat loss, and unregulated hunting. The Guadalupe Mountains (Texas) are now managed by the National Parks Service which wishes to restore native species to their historical range. A habitat suitability study is an important step in restoring desert bighorn sheep to the mountains since restoration efforts are labor intensive and costly. This study uses Geographic Information System (GIS) modeling to identify suitable areas within the park for bighorn sheep and evaluate possible migration corridors between the park and a nearby mountain range (Sierra Diablo) that currently supports more than 400 bighorn sheep. Landscape analysis was conducted to compare the spatial attributes of the habitat areas in the Guadalupe Mountains to those in the Sierra Diablo Mountain Range and assess habitat quality. Our results found 79.95km2 of suitable habitat for desert bighorn sheep in Guadalupe Mountains National Park which exceeds the established size to support a minimum viable population size of bighorn sheep (100–125 individuals). Landscape analysis indicated a larger area of optimal habitat at the park with larger mean patch size, lower edge density, and shorter mean nearest neighbor distance than in the Sierra Diablo mountain range. The Sierra Diablo was found to have a larger area of suitable habitat which may indicate that the park may be able to support a smaller population if water development mirrors that of the Sierra Diablo. Several migration corridors were identified between the park and areas with a viable population of bighorn sheep and this connectivity is important for migration and gene flow. Considerations should be given to water development, non-native, competitor species (Barbary sheep) and predators (mountain lions).

Magnetostratigraphy susceptibility for the Guadalupian series GSSPs (Middle Permian) in Guadalupe Mountains National Park and adjacent areas in West Texas

AbstractHere we establish a magnetostratigraphy susceptibility zonation for the three Middle Permian Global boundary Stratotype Sections and Points (GSSPs) that have recently been defined, located in Guadalupe Mountains National Park, West Texas, USA. These GSSPs, all within the Middle Permian Guadalupian Series, define (1) the base of the Roadian Stage (base of the Guadalupian Series), (2) the base of the Wordian Stage and (3) the base of the Capitanian Stage. Data from two additional stratigraphic successions in the region, equivalent in age to the Kungurian–Roadian and Wordian–Capitanian boundary intervals, are also reported. Based on low-field, mass specific magnetic susceptibility (χ) measurements of 706 closely spaced samples from these stratigraphic sections and time-series analysis of one of these sections, we (1) define the magnetostratigraphy susceptibility zonation for the three Guadalupian Series Global boundary Stratotype Sections and Points; (2) demonstrate that χ datasets provide a proxy for climate cyclicity; (3) give quantitative estimates of the time it took for some of these sediments to accumulate; (4) give the rates at which sediments were accumulated; (5) allow more precise correlation to equivalent sections in the region; (6) identify anomalous stratigraphic horizons; and (7) give estimates for timing and duration of geological events within sections.

Late Wisconsin Mammalian Fauna from Dust Cave, Guadalupe Mountains National Park, Culberson County, Texas

Three caves in Guadalupe Mountains National Park, Culberson County, Texas, are closely grouped spatially, and their fossil-bearing sediments are about the same late Pleistocene age. Publications concerning two of the caves, Upper Sloth Cave and Lower Sloth Cave, list and discuss their fossil faunas. Here, we add identifications of mammals from the third site, Dust Cave, and briefly comment on selected taxa. Tamias canipes or T. quadrivittatus (gray-footed or Colorado chipmunk), Tamias minimus (least chipmunk), Reithrodontomys (harvest mouse), Sigmodon ochrognathus (yellow-nosed cotton rat), Aztlanolagus agilis (Aztlán rabbit), and Sorex nanus (dwarf shrew) are added to the faunal list of the cave complex. More questionable identifications of taxa not recorded from the other caves include Ictidomys tridecemlineatus (thirteen-lined ground squirrel), Thomomys talpoides (northern pocket gopher), and Capromeryx (miniature pronghorns). Reexamination of several taxa from the Sloth caves did not confirm published records of Cryptotis parva (least shrew), but added Sorex merriami (Merriam's shrew) and confirmed the presence of Neotoma mexicana (Mexican woodrat) and Sorex cinereus (masked shrew).Tres cuevas en el Parque Nacional Guadalupe Mountains, condado de Culberson, Texas, están cerca de si, y sus sedimentos con fósiles representan aproximadamente el mismo periodo del pleistoceno tardío. Las publicaciones con respecto a dos de las cuevas, Upper Sloth Cave y Lower Sloth Cave, enlistan y discuten su fauna fósil. Aquí, agregamos identificaciones de mamíferos de la tercera cueva, Dust Cave, y brevemente comentamos sobre algunos taxa seleccionados. Tamias canipes o T. quadrivittatus (ardilla de pata gris o ardilla de Colorado), Tamias minimus (ardilla rayada menor), Reithrodontomys (ratón de cosecha), Sigmodon ochrognathus (rata algodonera de nariz amarilla), Aztlanolagus agilis (conejo de Aztlán), y Sorex nanus (musaraña enana) son añadidas a la lista de la fauna del complejo de cuevas. Identificación menos confiable de otros taxa que no fueron registrados para las otras cuevas incluyen Ictidomys tridecemlineatus (ardilla de tierra de trece líneas), Thomomys talpoides (tuza norteña), y Capromeryx (antílope miniatura). La revisión de varios taxa de las dos cuevas de Sloth no confirmó los registros publicados de Cryptotis parva (musaraña menor), pero agregó Sorex merriami (musaraña de Merriam) y confirmó la presencia de Neotoma mexicana (rata maderera) y Sorex cinereus (musaraña enmascarada).

Cougars in Guadalupe Mountains National Park, Texas: Estimates of Occurrence and Distribution Using Analysis of DNA

Abstract We used non-invasive genetic techniques to investigate the number and distribution of cougars (Puma concolor) inhabiting Guadalupe Mountains National Park, Texas. During 8 years, ≥31 resident and transient cougars were identified genetically and ≥15 individuals used the park in 2002. Based on estimates of size of home ranges of males and females, the park should support 4–6 resident adults. Genetic data suggest a high number of transients and, perhaps, an unstable population that may be the result of intense hunting pressure outside protected areas. Analysis of genetic diversity indicates restricted gene flow between the park and other populations in western Texas.

Status of Red Squirrels in Guadalupe Mountains National Park, Texas

The Pinaleno Mountains of southeastern Arizona contain the southernmost populatio no f red squirrels (Tamiasciurus hudsonicus) in North America. Red squirrels historically inhabited the Guadalupe Mountains in Trans-Pecos Texas during the Pleistocene and the possibility that red squirrels currently persist has been suggested by several biologists visiting the upper-elevation forests. Herein, we report results of an assessment of small mammals in coniferous forest where we used observational line transects, playback calls, and live trapping to determine status of red squirrels. We surveyed 132 ha of coniferous forest along 8.9 km of transects and observed and found evidence of 10 species of mammals. We detected no evidence of red squirrels inhabiting high-elevation coniferous forest.

Resolution of Respect: Professor Paul Schultz Martin 1928–2010

Resolution of Respect: Professor Paul Schultz Martin 1928–2010