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Geology topics

David M. Leslie

Publications and source records attributed to David M. Leslie.

At least 37 records · Page 2Linked to original sources
USGS2012

Spatio-temporal variations in age structures of a partially re-established population of northern river otters ( Lontra canadensis )

Examination of age structures and sex ratios is useful in the management of northern river otters ( Lontra canadensis ) and other furbearers. Reintroductions and subsequent recolonizations of river otters have been well documented, but changes in demographics between expanding and established populations have not been observed. As a result of reintroduction efforts, immigration from Arkansas and northeastern Texas, and other efforts, river otters have become partially reestablished throughout eastern and central Oklahoma. Our objective was to examine age structures of river otters in Oklahoma and identify trends that relate to space (watersheds, county) and time (USDA Animal and Plant Health Inspection Service county trapping records). We predicted that river otters in western areas of the state were younger than river otters occurring farther east. From 2005&ndash;2007, we obtained salvaged river otter carcasses from federal and state agencies, and we live-captured other river otters using leg hold traps. Seventy-two river otters were sampled. Overall, sex ratios were skewed toward females (1F∶0.8M), but they did not differ among spatiotemporal scales examined. Teeth were removed from salvaged and live-captured river otters (n = 63) for aging. One-year old river otters represented the largest age class (30.2%). Proportion of juveniles (<1 y old) in Oklahoma (19.0%) was less than other states. Mean age of river otters decreased from east-to-west in the Arkansas River and its tributaries. Mean age of river otters differed between the Canadian River Watershed (0.8 y) and the Arkansas River Watershed (2.9 y) and the Canadian River Watershed and the Red River Watershed (2.4 y). Proportion of juveniles did not differ among spatiotemporal scales examined. Similar to age structure variations in other mammalian carnivores, colonizing or growing western populations of river otters in Oklahoma contained younger ages than more established eastern populations.

American Midland Naturalist↗
USGS2012

Mammals of Red Slough Wildlife Management Area, with comments on McCurtain County, Oklahoma

Red Slough Wildlife Management Area (RSWMA) is located in the southeastern corner of Oklahoma, McCurtain County, and represents the extreme northwestern extent of the South Central Plains (SCP) ecoregion. Previous mammal research in southeastern Oklahoma has focused mostly on the Ouachita Mountains to the north of RSWMA. As a result, of the 69 species of mammals potentially occurring in McCurtain County, only 48 species represented by 599 voucher specimens reside in natural history collections. We present results from a mammal survey of RSWMA conducted from December 2009 to August 2010. We captured 574 non-volant small mammals in 9,115 trap-nights, 11 bats in 17 net-nights, and seven salvaged meso-mammals resulting in 157 voucher specimens of 22 mammal species, including the first specimen of Castor canadensis for McCurtain County, and photographic vouchers for eight additional species from RSWMA. These results provide a baseline for future studies on RSWMA and substantially increase our natural history knowledge for many relatively under-studied mammals in southeastern Oklahoma

Oklahoma↗
USGS2011

Restoration of the fire-grazing interaction in Artemisia filifolia shrubland of the Southern Great Plains, North America

1. &ensp;Patterns of landscape heterogeneity are crucial to the maintenance of biodiversity in shrublands and grasslands, yet management practices in these ecosystems typically seek to homogenize landscapes. Furthermore, there is limited understanding of how the interaction of ecological processes, such as fire and grazing, affects patterns of heterogeneity at different spatial scales. 2. &ensp;We conducted research in Artemisia filifolia (Asteraceae) shrublands located in the southern Great Plains of North America to determine the effect of restoring the fire&ndash;grazing interaction on vegetation structure. Data were collected for 3 years in replicated pastures grazed by cattle Bos taurus where the fire&ndash;grazing interaction had been restored (fire and grazing = treatment pastures) and in pastures that were grazed but remained unburned (grazing only, no fire = control pastures). The effect of the fire&ndash;grazing interaction on heterogeneity (variance) of vegetation structure was assessed at scales from 12&middot;5 m 2 to 609 ha. 3. &ensp;Most measurements of vegetation structure within treatment pastures differed from control pastures for 1&ndash;3 years after being burned but were thereafter similar to the values found in unburned control pastures. 4. &ensp;Treatment pastures were characterized by a lower amount of total heterogeneity and a lower amount of heterogeneity through time. 5. &ensp;Heterogeneity of vegetation structure tended to decrease as the scale of measurement increased in both treatment and control pastures. There was deviation from this trend, however, in the treatment pastures that exhibited much higher heterogeneity at the patch scale (mean patch size = 202 ha) of measurement, the scale at which patch fires were conducted. 6. Synthesis and applications .&ensp;Vegetation structure in A. filifolia shrublands of our study was readily altered by the fire&ndash;grazing interaction but also demonstrated substantial resilience to these effects. The fire&ndash;grazing interaction also changed the total amount of heterogeneity characterizing this system, the scale at which heterogeneity in this system was expressed and the amount of heterogeneity expressed through time. Land managers seeking to impose a shifting mosaic of heterogeneity on this vegetation type can do so by restoring the fire&ndash;grazing interaction with potential conservation benefits similar to what has been achieved in other ecosystems where historic cycles of disturbance and rest have been restored.

Oklahoma↗
USGS2011

Fire tolerance of a resprouting Artemisia (Asteraceae) shrub

In North America, most Artemisia (Asteraceae) shrub species lack the ability to resprout after disturbances that remove aboveground biomass. We studied the response of one of the few resprouting Artemisia shrubs, Artemisia filifolia (sand sagebrush), to the effects of prescribed fires. We collected data on A. filifolia density and structural characteristics (height, canopy area, and canopy volume) in an A. filifolia shrubland in the southern Great Plains of North America. Our study sites included areas that had not been treated with prescribed fire, areas that had been treated with only one prescribed fire within the previous 5 years, and areas that had been treated with two prescribed fires within the previous 10 years. Our data were collected at time periods ranging from 1/2 to 5 years after the prescribed fires. Density of A. filifolia was not affected by one or two fires. Structural characteristics, although initially altered by prescribed fire, recovered to levels characteristic of unburned areas in 3-4 years after those fires. In contrast to most non-sprouting North American Artemisia shrub species, our research suggested that the resprouting A. filifolia is highly tolerant to the effects of fire. ?? 2011 Springer Science+Business Media B.V.

Plant Ecology↗
USGS2011

Rusa unicolor (Artiodactyla: Cervidae)

Rusa unicolor (Kerr, 1792), or sambar, is the largest Oriental deer. Seven subspecies occur in varied habitats and elevations from India and Sri Lanka throughout southeastern Asia. Body mass and antler length decrease from west to east. R. unicolor is considered ancestral relative to the form of its male-only antlers and social behavior. Populations are vulnerable because of overexploitation for subsistence and markets in meat and antlers. R. unicolor was elevated by the International Union for Conservation of Nature and Natural Resources from no status in 2006 to “Vulnerable” in 2008 because of >50% decline in many populations over the past 3 generations. It is well represented in zoos and private collections and is introduced in Australia, New Zealand, South Africa, and the United States.

Mammalian Species↗
USGS2011

Rhinoceros sondaicus (Perissodactyla: Rhinocerotidae)

Rhinoceros sondaicus Desmarest, 1822, commonly called the Javan rhinoceros or lesser one-horned rhinoceros, is the most critically endangered large mammal on Earth with only 40-50 extant individuals in 2 disjunct and distant populations: most in Ujung Kulon, West Java, and only 2-6 (optimistically) in Cat Loc, Vietnam. R. sondaicus is polytypic with 3 recognized subspecies: R. s. sondaicus (currently West Java), R. s. inermis (formerly Sunderbunds; no doubt extinct), and R s. annamiticus (Vietnam; perhaps now extinct). R. sondaicus is a browser and currently occupies lowland semievergreen secondary forests in Ja va and marginal habitat in Vietnam; it was once more widespread and abundant, likely using a greater variety of habitats. R sondaicus has a very spotty history of husbandry, and no individuals are currently in captivity. Conservation focuses on protection from poaching and habitat loss. Following decades-long discussion of captive breeding and establishment of a 3rd wild population, conservation and governmental agencies appear closer to taking such seriously needed action on the latter.

Mammalian Species↗
USGS2011

Cerulean Warbler occurrence and habitat use in Oklahoma

Dendroica cerulea (Cerulean Warbler) is a migrant songbird that has declined rangewide in recent decades. We surveyed 150 sites in 2006&ndash;2007 to determine if this species still occupied its former breeding range in Oklahoma. We located Cerulean Warblers at 5 sites and confirmed breeding on north slopes of two heavily forested ridges in the Ouachita Mountains. We did not encounter Cerulean Warblers in any bottomland hardwoods, despite the former widespread distribution and abundance of the species in such habitats. While habitat loss and degradation may limit occurrence of Cerulean Warbler in some areas, the pattern of decline for this species at the edge of its range in Oklahoma is also consistent with abandonment of peripheral range as the range-wide population declines.

Oklahoma↗
USGS2010

Testing a Mahalanobis distance model of black bear habitat use in the Ouachita Mountains of Oklahoma

Regional wildlife&ndash;habitat models are commonly developed but rarely tested with truly independent data. We tested a published habitat model for black bears ( Ursus americanus ) with new data collected in a different site in the same ecological region (i.e., Ouachita Mountains of Arkansas and Oklahoma, USA). We used a Mahalanobis distance model developed from relocations of black bears in Arkansas to produce a map layer of Mahalanobis distances on a study area in neighboring Oklahoma. We tested this modeled map layer with relocations of black bears on the Oklahoma area. The distributions of relocations of female black bears were consistent with model predictions. We conclude that this modeling approach can be used to predict regional suitability for a species of interest.

Oklahoma↗
USGS2010

Procapra picticaudata (Artiodactyla: Bovidae)

Procapra picticaudata Hodgson, 1846, is commonly called the Tibetan gazelle, goa (= Tibetan), or zang yuan ling (= Chinese) and is monotypic. It is a high-elevation specialist endemic to the Tibetan Plateau where it prefers alpine meadow and alpine steppe but uses other lower-elevation plains and valleys. It is partial to good grasslands with high diversity of forbs. There have been no systematic estimates of total numbers of P. picticaudata. Populations are currently widespread but have been reduced from historic levels and are vulnerable because of poaching in remote areas and competition with livestock of pastoralists. P. picticaudata is uncommon in zoos and private collections. It is a threatened Class II species in China and considered &ldquo;Near Threatened" by the International Union for Conservation of Nature and Natural Resources.

Mammalian Species↗
USGS2010

Current distribution of North American river otters in central and eastern Oklahoma, with seven new county records

In 1984 and 1985, the Oklahoma Department of Wildlife Conservation reintroduced North American river otters (Lontra canadensis) from coastal Louisiana into eastern Oklahoma. Those reintroductions and immigration from Arkansas and possibly northeastern Texas allowed river otters to become reestablished in eastern Oklahoma. Our goals were to determine the contemporary distribution of river otters in central and eastern Oklahoma with voucher specimens, sign surveys, and mail surveys and to compare proportion of positive detections among watersheds. We report new distributional records with voucher specimens from seven counties (Adair, Bryan, Coal, Johnston, McIntosh, Okfuskee, Tulsa) in Oklahoma. We also provide locality information for specimens collected from four counties (Haskell, McCurtain, Muskogee, Wagoner) where river otters were described in published literature but no voucher specimens existed. During winter and spring 2006 and 2007, we visited 340 bridge sites in 28 watersheds in eastern and central Oklahoma and identified river otter signs in 16 counties where river otters were not previously documented in published literature or by voucher specimens. Proportion of positive sites within each watershed ranged 0&ndash;100%. Mail surveys suggested that river otters occurred in eight additional counties where they were not previously documented by published literature, voucher specimens, or sign-survey efforts.

Oklahoma↗
USGS2009

Conservation genetics of the alligator snapping turtle: cytonuclear evidence of range-wide bottleneck effects and unusually pronounced geographic structure

A previous mtDNA study indicated that female-mediated gene flow was extremely rare among alligator snapping turtle populations in different drainages of the Gulf of Mexico. In this study, we used variation at seven microsatellite DNA loci to assess the possibility of male-mediated gene flow, we augmented the mtDNA survey with additional sampling of the large Mississippi River System, and we evaluated the hypothesis that the consistently low within-population mtDNA diversity reflects past population bottlenecks. The results show that dispersal between drainages of the Gulf of Mexico is rare ( F ST msat = 0.43, &Phi; STmtDNA = 0.98). Past range-wide bottlenecks are indicated by several genetic signals, including low diversity for microsatellites (1.1&ndash;3.9 alleles/locus; H e = 0.06&ndash;0.53) and mtDNA ( h = 0.00 for most drainages; &pi; = 0.000&ndash;0.001). Microsatellite data reinforce the conclusion from mtDNA that the Suwannee River population might eventually be recognized as a distinct taxonomic unit. It was the only population showing fixation or near fixation for otherwise rare microsatellite alleles. Six evolutionarily significant units are recommended on the basis of reciprocal mtDNA monophyly and high levels of microsatellite DNA divergence.

Gulf of Mexico↗
USGS2009

Bos grunniens and Bos mutus (Artiodactyla: Bovidae)

Bos grunniens Linnaeus, 1766, and Bos mutus (Przewalski, 1883) are the domestic and wild forms, respectively, of the bovid commonly called the yak. B. mutus inhabits remote high-elevation alpine meadows and alpine steppe in rolling to mountainous terrain in the Tibetan Plateau, and B. grunniens is maintained widely in China and other parts of Central Asia, and uncommonly elsewhere in the world. Populations of B. mutus are substantially reduced and fragmented throughout its remaining range; the largest numbers occur in northern Tibet and western Qinghai. B. mutus is vulnerable because of poaching and competition with domestic livestock. Although no complete survey of B. mutus has been conducted, there are probably no more than 15,000 remaining in remote areas of the Tibetan Plateau; B. grunniens numbers about 14 million.

Mammalian Species↗
USGS2009

Influence of Old World bluestem (Bothrichloa ischaemum) monocultures on breeding density of three grassland songbirds in Oklahoma

Despite persistent and widespread declines of grassland birds in North America, few studies have assessed differences between native grasslands and seeded monocultures as songbird habitat. In the Great Plains, many fields enrolled in the Conservation Reserve Program have been seeded to Old World bluestems (OWB), but there is evidence to suggest that OWB may not provide suitable conditions for several grassland bird species. Our objectives were to investigate the influence of OWB monocultures on vegetation structure, composition, and breeding densities of three common grassland bird species. In 2007, we used distance sampling to survey breeding songbirds in 6 native mixed grass prairie and 6 OWB fields in Garfield, Grant, and Alfalfa counties, Oklahoma. Native mixed grass prairie supported taller and denser vegetation, as well as greater forb cover than OWB fields. Breeding density of Grasshopper Sparrow ( Ammodramus savannarum ) was higher in OWB monocultures, while density of Dickcissel ( Spiza americana ) and Eastern Meadowlark ( Sturnella magna ) was similar among field types.

Oklahoma↗
USGS2008

Subspecific affinities and conservation genetics of western big-eared bats (Corynorhinus townsendii pallescens) at the edge of their distributional range

Subspecific affinities, determination of population boundaries, and levels of population connectedness are of critical importance for the development of management and conservation planning. We used variation at a mitochondrial locus and 5 biparentally inherited nuclear loci to determine partitioning of genetic variation of western big-eared bats (Corynorhinus townsendii) within and among caves occurring in a fragmented landscape of gypsum deposits in western Oklahoma. To accomplish this objective, we first performed a phylogenetic analysis based on the mitochondrial locus of western big-eared bats from a large portion of their range. This analysis indicated that western big-eared bats at the periphery of the distribution in western Oklahoma share phylogenetic affinities with the most geographically restricted subspecies, C. t. pallescens. Because C. townsendii is rare in Oklahoma and is listed as a species of special concern, this finding provides additional support for the continued protection of this species in Oklahoma. Within western Oklahoma, we failed to detect significant differentiation among any caves for the biparentally inherited microsatellite data. However, the mitochondrial locus exhibited significant levels of genetic differentiation among caves, with the highest level of differentiation occurring between caves within the disjunct distributions of gypsum (??ST = 38.76%). Although a significant amount of genetic differentiation was detected between populations on the 2 disjunct distributions of gypsum deposits, Analysis with the program Migrate suggested high levels of asymmetric gene flow among some populations. Our results provide a greater understanding of the population dynamics of western big-eared bats on the periphery of their range and highlight the importance of continued monitoring and study of this taxon. ?? 2008 American Society of Mammalogists.

Journal of Mammalogy↗
USGS2008

Relative abundance of mesopredators and size of oak patches in the cross-timbers ecoregion

Mesopredators (e.g., raccoon Procyon lotor, Virginia opossum Didelphis virginiana, striped skunk Mephitis mephitis) have received considerable attention because of links to population declines in birds via increased nest predation, especially in landscapes fragmented by anthropogenic forces. Relationships of abundance of mesopredators to size of habitat patches have received less attention than relationships to other metrics of fragmentation, particularly edge characteristics. We tested the hypothesis that relative abundance of mesopredators (e.g., raccoons and Virginia opossums) was related negatively to size of forest patch. We delineated 15 patches of oak (Quercus) forest ranging from 0.2 to 55.3 ha within a grassland-woodland mosaic in the cross-timbers ecoregion of Oklahoma. Scent stations and live traps within these patches were used to index relative abundance of mesopredators in summers 2003 and 2004. Both indices of relative abundance were related weakly and negatively to area of forest patch. However, rate of capture and visitation to scent station were not correlated consistently throughout the study. Our results suggested that the two methods to index abundance provided separate information on functional and numerical responses to size of patch. Our evidence that mesopredators within the cross timbers were more likely to be in smaller patches of oak forest may have implications to success of avian nesting in these patches.

Southwestern Naturalist↗
USGS2008

Invertebrate community response to a shifting mosaic of habitat

Grazing management has focused largely on promoting vegetation homogeneity through uniform distribution of grazing to minimize area in a pasture that is either heavily disturbed or undisturbed. An alternative management model that couples grazing and fire (i.e., patch burning) to promote heterogeneity argues that grazing and fire interact through a series of positive and negative feedbacks to cause a shifting mosaic of vegetation composition and structure across the landscape. We compared patch burning with traditional homogeneity-based management in tallgrass prairie to determine the influence of the two treatments on the aboveground invertebrate community. Patch burning resulted in a temporal flush of invertebrate biomass in patches transitional between unburned and patches burned in the current year. Total invertebrate mass was about 50% greater in these transitional patches within patch-burned pastures as compared to pastures under traditional, homogeneity-based management. Moreover, the mosaic of patches in patch-burned pastures contained a wider range of invertebrate biomass and greater abundance of some invertebrate orders than did the traditionally managed pastures. Patch burning provides habitat that meets requirements for a broad range of invertebrate species, suggesting the potential for patch burning to benefit other native animal assemblages in the food chain.

Rangeland Ecology and Management↗