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Geology topics

David A. Haukos

Publications and source records attributed to David A. Haukos.

At least 91 records · Page 5Linked to original sources
USGS2016

Landscape composition creates a threshold influencing Lesser Prairie-Chicken population resilience to extreme drought

Habitat loss and degradation compound the effects of climate change on wildlife, yet responses to climate and land cover change are often quantified independently. The interaction between climate and land cover change could be intensified in the Great Plains region where grasslands are being converted to row-crop agriculture concurrent with increased frequency of extreme drought events. We quantified the combined effects of land cover and climate change on a species of conservation concern in the Great Plains, the Lesser Prairie-Chicken ( Tympanuchus pallidicinctus ). We combined extreme drought events and land cover change with lek count surveys in a Bayesian hierarchical model to quantify changes in abundance of male Lesser Prairie-Chickens from 1978 to 2014 in Kansas, the core of their species range. Our estimates of abundance indicate a gradually decreasing population through 2010 corresponding to drought events and reduced grassland areas. Decreases in Lesser Prairie-Chicken abundance were greatest in areas with increasing row-crop to grassland land cover ratio during extreme drought events, and decreased grassland reduces the resilience of Lesser Prairie-Chicken populations to extreme drought events. A threshold exists for Lesser Prairie-Chickens in response to the gradient of cropland:grassland land cover. When moving across the gradient of grassland to cropland, abundance initially increased in response to more cropland on the landscape, but declined in response to more cropland after the threshold ( δ=0.096 , or 9.6% cropland). Preservation of intact grasslands and continued implementation of initiatives to revert cropland to grassland should increase Lesser Prairie-Chicken resilience to extreme drought events due to climate change.

Kansas↗
USGS2016

Effectiveness of vegetation buffers surrounding playa wetlands at contaminant and sediment amelioration

Playa wetlands, the dominant hydrological feature of the semi-arid U.S. High Plains providing critical ecosystem services, are being lost and degraded due to anthropogenic alterations of the short-grass prairie landscape. The primary process contributing to the loss of playas is filling of the wetland through accumulation of soil eroded and transported by precipitation from surrounding cultivated watersheds. We evaluated effectiveness of vegetative buffers surrounding playas in removing metals, nutrients, and dissolved/suspended sediments from precipitation runoff. Storm water runoff was collected at 10-m intervals in three buffer types (native grass, fallow cropland, and Conservation Reserve Program). Buffer type differed in plant composition, but not in maximum percent removal of contaminants. Within the initial 60 m from a cultivated field, vegetation buffers of all types removed >50% of all measured contaminants, including 83% of total suspended solids (TSS) and 58% of total dissolved solids (TDS). Buffers removed an average of 70% of P and 78% of N to reduce nutrients entering the playa. Mean maximum percent removal for metals ranged from 56% of Na to 87% of Cr. Maximum removal was typically at 50 m of buffer width. Measures of TSS were correlated with all measures of metals and nutrients except for N, which was correlated with TDS. Any buffer type with >80% vegetation cover and 30–60 m in width would maximize contaminant removal from precipitation runoff while ensuring that playas would continue to function hydrologically to provide ecosystem services. Watershed management to minimize erosion and creations of vegetation buffers could be economical and effective conservation tools for playa wetlands.

Journal of Environmental Management↗
USGS2016

Lesser prairie-chicken avoidance of trees in a grassland landscape

Grasslands are among the most imperiled ecosystems in North America. Reasons that grasslands are threatened include conversion to row-crop agriculture, fragmentation, and changes in fire regimes. The reduction of fire processes in remaining prairies has resulted in tree encroachment and establishment in grasslands, further reducing grassland quantity and quality. Grassland birds have been experiencing precipitous population declines in recent decades, commensurate with landscape changes to grasslands. The lesser prairie-chicken ( Tympanuchus pallidicinctus Ridgway) is a declining species of prairie grouse of conservation concern. We used second- and third-order habitat selection metrics to test if female lesser prairie-chickens avoid grasslands where trees were present. Our results indicated that female lesser prairie-chickens selected habitats avoiding the nearest trees by 283 m on average, nearly twice as far as would be expected at random. Lesser prairie-chickens were 40 times more likely to use habitats with tree densities of 0 trees ∙ ha − 1 than habitats with 5 trees ∙ ha − 1 . Probability of use indicated that lesser prairie-chickens were 19 times more likely to use habitats 1000 m from the nearest tree when compared with using habitats 0 m from the nearest tree. Nest survival was not affected at densities < 2 trees ∙ ha − 1 ; however, we could not test if nest survival was affected at greater tree densities as no nests were detected at densities > 2 trees ∙ ha − 1 . Avoidance of trees could be due to perceived increased predation risk, reduced habitat quality, or a combination of these potentially confounding factors. Preventing further establishment and expansion of trees in landscapes occupied by lesser prairie-chickens could contribute to the continued persistence of the species. Additionally, restoring grasslands through tree removal may facilitate conservation efforts for grassland species such as the lesser prairie-chicken by improving habitat quality and promoting expansion of occupied range.

Kansas↗
USGS2016

Use of free water by nesting lesser prairie-chickens

The lesser prairie-chicken ( Tympanuchus pallidicinctus ) is a grassland grouse of semiarid regions. Use of free water has been hypothesized as necessary for egg formation during drought. We assessed the use of hydrogen isotopes (deuterium, δ 2 H) to determine if female lesser prairie-chickens use and incorporate free water during egg formation by testing the relationship between isotope ratios in available free water and eggshells. We collected eggshells from 124 nests and 282 free water samples from three sites in Kansas in 2013 and 2014. Eggshells had δ 2 H values similar to free water in the year of severe drought but were dissimilar the year with lessened drought severity. With an established link between lesser prairie-chicken eggshells and free water during severe drought, we have identified a mechanism behind observations of lesser prairie-chicken water use. We have demonstrated that hydrogen isotopes can be used to test research questions related to use of free water.

Southwestern Naturalist↗
USGS2016

Restoring sand shinnery oak prairies with herbicide and grazing in New Mexico

Sand shinnery oak ( Quercus havardii ) prairies are increasingly disappearing and increasingly degraded in the Southern High Plains of Texas and New Mexico. Restoring and managing sand shinnery oak prairie can support biodiversity, specific species of conservation concern, and livestock production. We measured vegetation response to four treatment combinations of herbicide (tebuthiuron applied at 0.60 kg/ha) and moderate-intensity grazing (50% removal of annual herbaceous production) over a 10-year period in a sand shinnery oak prairie of eastern New Mexico. We compared the annual vegetation response to the historical climax plant community (HCPC) as outlined by the U.S. Department of Agriculture Ecological Site Description. From 2 to 10 years postapplication, tebuthiuron-treated plots had reduced shrub cover with twice as much forb and grass cover as untreated plots. Tebuthiuron-treated plots, regardless of the presence of grazing, most frequently met HCPC. Tebuthiuron and moderate-intensity grazing increased vegetation heterogeneity and, based on comparison of the HCPC, successfully restored sand shinnery oak prairie to a vegetation composition similar to presettlement.

New Mexico↗
USGS2016

Ecology and conservation of Lesser Prairie-Chickens in sand shinnery oak prairies

Sand shinnery oak (Quercus havardii) prairies are unique ecosystems endemic to sandy soils of eastern New Mexico, northwestern Texas, and western Oklahoma; the historic and current distribution of the Lesser Prairie-Chicken (Tympanuchus pallidicinctus) overlaps these prairie systems. Lesser Prairie-Chicken populations in sand shinnery oak prairies of the Southern Great Plains have declined substantially since the late 1980s, most likely due to conversion of nesting and brood-rearing habitat to row-crop agriculture and extended periods of drought. In addition to threats universal throughout the species distribution, this population is susceptible to a changing climate in an area that is already representative of an extreme environment for ground-nesting birds. Recent studies of Lesser Prairie-Chicken ecology in sand shinnery oak prairies have expanded our knowledge on the ecology and management of the species, but a thorough review of the historic and current literature is lacking. In addition, current management guidelines exist for Lesser Prairie-Chickens in mixed grass and sand sagebrush prairies, but there are no comprehensive management guidelines for the species in sand shinnery oak prairies. This information is paramount given unique aspects of the vegetation community, relative ecosystem drivers, and environmental variation in sand shinnery oak prairie and the species’ current status as a proposed threatened species under the United States Endangered Species Act. Herein, we provide a thorough synthesis of literature pertaining to the life history, habitat requirements, habitat management, and population management for Lesser Prairie-Chickens in sand shinnery oak prairie, provide management guidelines and recommendations for the species in this ecoregion, and highlight current and future research needs. Within our objectives, we place emphasis on two recently completed long-term investigations into Lesser Prairie-Chicken ecology in sand shinnery oak prairie - a 10-year vegetation data set collected in Roosevelt County, New Mexico, 2001–2011 and a 6-year Lesser Prairie-Chicken data set collected in Roosevelt County, New Mexico and Cochran, Hockley, Terry, and Yoakum counties, Texas, 2006–2012.

Book chapter↗
USGS2016

Harvest

No abstract available.

Book chapter↗
USGS2015

Factors affecting female space use in ten populations of prairie chickens

Conservation of wildlife depends on an understanding of the interactions between animal movements and key landscape factors. Habitat requirements of wide-ranging species often vary spatially, but quantitative assessment of variation among replicated studies at multiple sites is rare. We investigated patterns of space use for 10 populations of two closely related species of prairie grouse: Greater Prairie-Chickens ( Tympanuchus cupido ) and Lesser Prairie-Chickens ( T. pallidicinctus ). Prairie chickens require large, intact tracts of native grasslands, and are umbrella species for conservation of prairie ecosystems in North America. We used resource utilization functions to investigate space use by female prairie chickens during the 6-month breeding season from March through August in relation to lek sites, habitat conditions, and anthropogenic development. Our analysis included data from 382 radio-marked individuals across a major portion of the extant range. Our project is a unique opportunity to study comparative space use of prairie chickens, and we employed standardized methods that facilitated direct comparisons across an ecological gradient of study sites. Median home range size of females varied ~10-fold across 10 sites (3.6–36.7 km 2 ), and home ranges tended to be larger at sites with higher annual precipitation. Proximity to lek sites was a strong and consistent predictor of space use for female prairie chickens at all 10 sites. The relative importance of other predictors of space use varied among sites, indicating that generalized habitat management guidelines may not be appropriate for these two species. Prairie chickens actively selected for prairie habitats, even at sites where ~90% of the land cover within the study area was prairie. A majority of the females monitored in our study (>95%) had activity centers within 5 km of leks, suggesting that conservation efforts can be effectively concentrated near active lek sites. Our data on female space use suggest that lek surveys of male prairie chickens can indirectly assess habitat suitability for females during the breeding season. Lek monitoring and surveys for new leks provide information on population trends, but can also guide management actions aimed at improving nesting and brood-rearing habitats.

Ecosphere↗
USGS2015

Baseline blood Pb levels of black-necked stilts on the upper Texas coast

There are no known biological requirements for lead (Pb), and elevated Pb levels in birds can cause a variety of sub-lethal effects and mortality. Historic and current levels of Pb in mottled ducks ( Anas fulvigula ) suggest that environmental sources of Pb remain available on the upper Texas coast. Because of potential risks of Pb exposure among coexisting marsh birds, black-necked stilt ( Himantopus mexicanus ) blood Pb concentrations were measured during the breeding season. Almost 80 % (n = 120) of 152 sampled stilts exceeded the background threshold (>20 &mu;g/dL) for Pb exposure. However, blood Pb concentrations did not vary by age or gender, and toxic or potentially lethal concentrations were rare (<5 %). Consistent, low-level blood Pb concentrations of black-necked stilts in this study suggest the presence of readily bioavailable sources of Pb, although potential impacts on local stilt populations remain unclear.

Bulletin of Environmental Contamination and Toxico↗
USGS2015

Opinion: Endogenizing culture in sustainability science research and policy

Integrating the analysis of natural and social systems to achieve sustainability has been an international scientific goal for years ( 1 , 2 ). However, full integration has proven challenging, especially in regard to the role of culture ( 3 ), which is often missing from the complex sustainability equation. To enact policies and practices that can achieve sustainability, researchers and policymakers must do a better job of accounting for culture, difficult though this task may be. The concept of culture is complex, with hundreds of definitions that for years have generated disagreement among social scientists ( 4 ). Understood at the most basic level, culture constitutes shared values, beliefs, and norms through which people “see,” interpret, or give meaning to ideas, actions, and environments. Culture is often used synonymously with “worldviews” or “cosmologies” ( 5 , 6 ) to explain the patterned ways of assigning meanings and interpretations among individuals within groups. Used in this way, culture has been found to have only limited empirical support as an explanation of human risk perception ( 7 , 8 ) and environmentalism ( 9 ).

Proceedings of the National Academy of Sciences of↗
USGS2015

Evaluation of capture techniques on lesser prairie-chicken trap injury and survival

Ethical treatment of research animals is required under the Animal Welfare Act. This includes trapping methodologies that reduce unnecessary pain and duress. Traps used in research should optimize animal welfare conditions within the context of the proposed research study. Several trapping techniques are used in the study of lesser prairie-chickens, despite lack of knowledge of trap injury caused by the various methods. From 2006 to 2012, we captured 217, 40, and 144 lesser prairie-chickens Tympanuchus pallidicinctus using walk-in funnel traps, rocket nets, and drop nets, respectively, in New Mexico and Texas, to assess the effects of capture technique on injury and survival of the species. We monitored radiotagged, injured lesser prairie-chickens 7&ndash;65 d postcapture to assess survival rates of injured individuals. Injuries occurred disproportionately among trap type, injury type, and sex. The predominant injuries were superficial cuts to the extremities of males captured in walk-in funnel traps. However, we observed no mortalities due to trapping, postcapture survival rates of injured birds did not vary across trap types, and the daily survival probability of an injured and uninjured bird was &ge;99%. Frequency and intensity of injuries in walk-in funnel traps are due to the passive nature of these traps (researcher cannot select specific individuals for capture) and incidental capture of individuals not needed for research. Comparatively, rocket nets and drop nets allow observers to target birds for capture and require immediate removal of captured individuals from the trap. Based on our results, trap injuries would be reduced if researchers monitor and immediately remove birds from walk-in funnels before they injure themselves; move traps to target specific birds and reduce recaptures; limit the number of consecutive trapping days on a lek; and use proper netting techniques that incorporate quick, efficient, trained handling procedures.

Journal of Fish and Wildlife Management↗
USGS2015

Blood lead exposure concentrations in mottled ducks ( Anas fulvigula ) on the upper Texas coast

The mottled duck (Anas fulvigula) is a non-migratory waterfowl species dependent upon coastal marsh systems, including those on the Texas Chenier Plain National Wildlife Refuge (NWR) Complex, and considered a regional indicator species of marsh habitat quality. Research from the early 1970s, 1990s, and early-2000s indicated that mottled ducks continued to exhibit elevated wing-bone lead (Pb) concentrations, decades after implementation of non-toxic shot regulations. However, wing-bone concentrations reflect lifetime accumulation of Pb, whereas blood Pb concentrations reflect more recent exposure. To identify current potentially relevant temporal windows of Pb exposure, we collected 260 blood samples from mottled ducks during summer (n=124) and winter (n=136) from 2010&ndash;2012 on the Texas Chenier Plain NWR Complex. We quantified baseline blood Pb concentrations for all ages of mottled ducks, and hypothesized that blood lead concentrations would remain elevated above background levels (200 &micro;g L&ndash;1) despite the 1983 and 1991 lead shot bans. Blood Pb concentrations ranged from below detection limits to >12,000 &micro;g L&ndash;1, where >200 &micro;g L&ndash;1 was associated with exposure levels above background concentrations. Male mottled ducks had the greatest blood Pb concentrations (30 times greater than females) with concentrations greater during winter than summer. Likewise, the proportion of exposed (>200 &micro;g L&ndash;1) females increased from 14%&ndash;47% from summer to winter, respectively. Regardless of sex, adult mottled duck blood Pb concentrations were five times greater than juveniles, particularly during winter. We identified five plausible models that influenced blood Pb levels where year, site, and interactions among age*sex*season and between age*season were included in the top-ranked models. Frequency of exposure was greatest during winter, increasing from 12% in summer to 55% in winter, indicating that a temporal exposure window to environmental Pb exists between nesting and hunting seasons. Blood Pb concentrations remain elevated in mottled ducks despite Pb shot bans enacted >25 years prior to this study. If Pb levels in mottled ducks becomes a conservation concern, regional monitoring of blood Pb concentrations would be appropriate with a focus upon elucidating potential reasons for the variation among age and sex groups. Finally, identifying potentially available sources of environmental Pb may be key to minimizing this apparently persistent threat to mottled ducks on the upper Texas coast.

Journal of the Southeastern Association of Fish an↗
USGS2015

Survival and recovery rates of mottled ducks banded in Texas and Louisiana

The Western Gulf Coast population of the mottled duck (Anas fulvigula) is dependent on the Gulf coastal marsh to complete its entire life cycle. Band recovery data can be used to monitor mottled duck populations by estimating annual survival, indexing harvest rate, and assessing movements. Band returns from hunting seasons 1997–2013 were used to evaluate factors influencing annual survival, recovery rates, and movements of mottled ducks in Texas and Louisiana. For banding years of 1997–2013, 58,349 normal, wild mottled ducks were banded and released in Texas and Louisiana. Since 2002, 86% of mottled duck bandings have occurred on the Chenier Plain of Texas and Louisiana. Hunters shot, recovered, and reported 7,061birds with bands during this period. Direct recovery rates were greater for juveniles than adults but changed little since the 1970s. Estimates of annual survival did not differ between Texas and Louisiana, but did among years and between sex and age classes. Adult male and juvenile female mottled ducks had the greatest and lowest annual survival rates, respectively. Recovery of birds banded on the Chenier Plain was four times greater for birds banded in Texas and harvested in Louisiana than banded in Louisiana and harvested in Texas. Much of the current inference of results from banding mottled ducks is limited to the Chenier Plain. To monitor the entire Western Gulf Coast population of mottled ducks, managers can consider expanding operational banding operations with annual quotas, which would improve survival and recovery estimates and allow for inference beyond the Chenier Plain region.

Louisiana, Texas↗
USGS2015

Duckling survival, fecundity, and habitat selection of mottled duck broods on the upper Texas Gulf Coast

Mottled ducks (Anas fulvigula) on the western Gulf Coast have exhibited a steep population decline since the mid 1990s. Low rates of breeding incidence and nest success have been implicated in this decline, but duckling survival and the habitat needs of broods have not been previously investigated in this region. We fitted mottled duck ducklings and adult females with radio transmitters and tracked broods to estimate duckling survival and brood habitat selection on the upper Texas Gulf Coast. Duckling survival to 30 days was high (range among models 0.354–0.567) compared to other dabbling duck species. Estimated fecundity was low, (range among models 0.398–0.634) however, indicating that overall reproductive output is low. Within coastal marsh, broods selected home ranges with more water cover and less upland and fresh marsh landcover than was available in the study area. Within coastal marsh home ranges, broods selected for water cover relative to other landcover types, and there was some evidence that broods avoided unvegetated landcover. Although high quality brood habitat is undeniably important, management efforts to increase mottled duck population growth on the western Gulf Coast may best be spent on increasing nesting habitat quality to increase nest success and breeding incidence.

Texas↗
USGS2015

Mottled duck (Anas fulvigula) movements in the Texas Chenier Plain Region

As a surrogate species for Strategic Habitat Conservation, the mottled duck (Anas fulgivula) is an indicator species to coastal marsh health and function. Currently, biologists have a relatively poor understanding of regional mottled duck movements. We outfitted adult female mottled ducks with solar satellite transmitters during summer 2009–2011. Movement patterns were measured among years and phenology, in relation to available habitat at the landscape level, and in association to potential disturbance. Movement distances were measured in ArcGIS and then evaluated using analysis of variance for independent variables of year, month, biological time period, and season. Average weekly distances traveled by mottled ducks were relatively short (<5,000m) compared to other waterfowl. Movement occurrence and distance were linked to biological season with longest distances documented during the molt period. Movements also differed among years, with drought conditions associated with longer movement distances. Magnitude of movements may be an indicator of habitat quality for mottled ducks in the Texas Chenier Plain Region. By focusing on providing large freshwater pools and fresh/intermediate marsh during the molt period, managers could positively impact mottled ducks.

Texas↗
USGS2014

Northern Pintail

This medium-sized dabbling duck of slender, elegant lines and conservative plumage coloration is circumpolar in distribution and abundant in North America, with core nesting habitat in Alaska and the Prairie Pothole Region of southern Canada and the northern Great Plains. Breeders favor shallow wetlands interspersed throughout prairie grasslands or arctic tundra. An early fall migrant, the species arrives on wintering areas beginning in August, after wing molt, often forming large roosting and feeding flocks on open, shallow wetlands and flooded agricultural fields. The birds consume grains, marsh plant seeds, and aquatic invertebrates throughout fall and winter. Northern Pintails are among the earliest nesting ducks in North America, beginning shortly after ice-out in many northern areas. Individuals form new pair bonds each winter but are highly promiscuous during the nesting season, with mated and unmated males often involved in vigorous, acrobatic Pursuit Flights. Annual nest success and productivity vary with water conditions, predation, and weather. Females build nests on the ground, often far from water. Only the female incubates; her mate leaves shortly after incubation begins. Ducklings hatch together in one day, follow the female to water after a day in the nest, and fledge by July or August. Adults and ducklings consume mainly aquatic invertebrates during the breeding season. Predators and farming operations destroy many thousands of Northern Pintail nests annually; farming has also greatly reduced the amount of quality nesting cover available. Winter habitats are threatened by water shortages, agricultural development, contamination, and urbanization. Periods of extended drought in prairie nesting regions have caused dramatic population declines, usually followed by periods of recovery. Over the long term, however, the continental population of Northern Pintails has declined significantly from 6 million birds in the early 1970s to less than 3 million in the late 1980s and early 1990s. Since then, the population appears to have stabilized; in 2013, the estimate was 3.3 million birds, a large number but below conservation goals despite favorable wetland conditions in much of the prairie breeding region. Ongoing conservation measures, however, such as habitat restoration and enhancement of agricultural lands, as well as prudent harvest management, suggest that Northern Pintails should have a secure future in North America.

The Birds of North America↗