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The Honors College at Texas A&M University-Kingsville was established in 2010. At that time, student retention rate at Texas A&M-Kingsville was at 56%, one of the lowest rates in Texas. In an effort to determine if the establishment of the Honors College on campus has made a positive impact on First Time In College (FTIC) student retention rates, data on all FTIC students between 2005 and 2014 was collected, which included: ethnicity (Hispanic/nonHispanic), first generation/non-first generation, ACT/SAT scores, if the student participated in the Honors College or not during their first year, and if the student was retained to the sophomore year at Texas A&M-Kingsville. Results indicate that the Honors College has had a positive impact on retention rates of FTIC students in the Honors College compared to the general student population. Retention rates since 2010 have increased for the entire university, with a retention rate of 69% for all FTIC students in the 2014 cohort. On average, the Honors College improved retention rates for Honors College students 25% compared to the general student population, 27% for first generation students, and 26% for Hispanic students. Likewise, the Honors College improved retention rates for Honors College students 11.5% compared to students on campus who could have joined the Honors College given their SAT/ACT scores. The results of this study show that the Honors College has had a positive impact at a rural, Hispanic Serving Institution and could serve as a model for other universities with similar student demographics to help boost retention rates of high-achieving students.

Rangelands in the southwestern United States represent a current stronghold for northern bobwhite (Colinus virginianus); however, bobwhite populations in rangelands exhibit extreme inter‐annual variability in abundance in relation to fluctuating weather patterns. Recent declining bobwhite population trends within this region have led to the supposition that landscape‐scale processes, such as habitat loss and fragmentation and predation from increased raptor abundance, may be acting in conjunction with weather to reduce bobwhite populations. Our objective was to determine the relative effects of these factors on bobwhite populations in the rangeland environments of Texas and Oklahoma, USA. We obtained publicly available datasets for bobwhite counts (Breeding Bird Survey, state‐agency roadside counts), weather (PRISM), land cover (National Land Cover Database), and raptors (Christmas Bird Counts) for 3 5‐year periods (1990–1994, 1999–2003, 2009–2013). Data were collected at route and landscape scales based on routes within the Rio Grande Plains region of Texas and the Central Mixed Grass Prairie region of Texas and Oklahoma. We used generalized linear mixed models with a backward selection approach to determine top models for each dataset based on scale and ecoregion. Covariate relationships with bobwhite abundance followed expected patterns, with positive relationships with habitat, precipitation, and minimum temperatures and negative relationships with maximum temperatures and raptor abundance. Weather variables were the factors most consistently selected within both regions, while minimum winter temperature was overall the top variable. These relationships occurred within a landscape still containing relatively vast amounts of unfragmented bobwhite habitat (>60% rangeland; >15 million ha). Management within these regions should be focused on retaining habitat at a broad scale, while managing for suitable cover at a local scale to help mitigate weather effects. [ABSTRACT FROM AUTHOR]

Climate change is altering biodiversity of ecosystems worldwide by causing shifts in species' home ranges, potential extinctions of species, and Extreme Climatic Events (ECEs), such as hurricanes and extreme temperatures. The purpose of this study was to examine effects of two extreme weather events on butterfly populations in the Gulf Prairies and Marshes ecoregion in Willacy and Kenedy Counties, TX, USA. These weather events occurred during an ongoing study of effects of prescribed burning during summer or winter on butterfly populations. We tested effects of Category 1 Hurricane Hanna by comparing butterfly abundance in the month prior to and following the hurricane (July and August 2020). We tested effects of Winter Storm Uri by comparing butterfly abundance in the three months following the storm (March through May 2021) with abundance during the same period in the previous year (March through May 2020). We measured no effect of the Category 1 hurricane on butterfly populations overall and across all prescribed fire regimes. There was a significant reduction in butterfly abundance following the 2021 winter storm, and effects depended on prescribed fire regime. Our findings indicate that extremely cold temperatures in subtropical regions will likely have greater negative effects on butterfly populations than low-magnitude hurricanes. Implications for insect conservation: With extreme climate events (ECEs) predicted to increase in the future, measures should be taken to provide protection and refugia for butterflies, particularly from prolonged, uncharacteristically low temperatures. Protection includes maintaining undisturbed areas with accumulated plant matter, in preparation for these unpredictable events. [ABSTRACT FROM AUTHOR]

Plant species richness is an important property of ecosystems that is altered by grazing. In a semiarid environment, we tested the hypotheses that (1) small‐scale herbaceous plant species richness declines linearly with increasing grazing intensity by large ungulates, (2) precipitation and percent sand interact with grazing intensity, and (3) response of herbaceous plant species richness to increasing intensity of ungulate grazing varies with patch productivity. During January–March 2012, we randomly allocated 50, 1.5‐m × 1.5‐m grazing exclosures within each of six 2500 ha study sites across South Texas, USA. We counted the number of herbaceous plant species and harvested vegetation in 0.25‐m2 plots within exclosures (ungrazed control plots) and in the grazed area outside the exclosures (grazed treatment plots) during October–November 2012–2019. We estimated percent use (grazing intensity) based on the difference in herbaceous plant standing crop between control plots and treatment plots. We selected the negative binomial regression model that best explained the relationship between grazing intensity and herbaceous plant species richness using the Schwarz‐Bayesian information criterion. After accounting for the positive effect of precipitation and percent sand on herbaceous plant species richness, species richness/0.25 m2 increased slightly from 0% to 30% grazing intensity and then declined with increasing grazing intensity. Linear and quadratic responses of herbaceous plant species richness to increasing grazing intensity were greater for the least productive patches (<15.7 g/0.25 m2) than for productive patches (≥15.7 g/0.25 m2). Our results followed the pattern predicted by the intermediate disturbance hypothesis model for the effect of grazing intensity on small‐scale herbaceous plant species richness. [ABSTRACT FROM AUTHOR]

Identification of buildings from remotely sensed imagery in urban and suburban areas is a challenging task. Light detection and Ranging (LiDAR) provides an opportunity to accurately identify buildings by identification of planar surfaces. Dense vegetation can limit the number of light particles that reach the ground, potentially creating false planar surfaces within a vegetation stand. We present an application of discriminant analysis (a commonly used statistical tool in decision theory) to classify polygons (derived from LiDAR) as either buildings or a non-building planar surfaces. We conducted our analysis in southern Texas where thornscrub vegetation often prevents a LiDAR beam from fully penetrating the vegetation canopy in and around residential areas. Using discriminant analysis, we grouped potential building polygons into building and non-building classes using the point densities of ground, unclassified, and building points. Our technique was 95% accurate at distinguishing buildings from non-buildings. Therefore, we recommend its use in any locale where distinguishing buildings from surrounding vegetation may be affected by the proximity of dense vegetation to buildings. [ABSTRACT FROM AUTHOR]

Wildlife-vehicle collisions can have a substantial influence on the mortality rates of many wildlife populations. Crossing structures are designed to mitigate the impact of road mortality by allowing safe passage of wildlife above or below roads, and connect to suitable areas on both sides of the road. Ocelots (Leopardus pardalis) are a federally endangered felid in the United States, with remnant populations of <80 individuals remaining in the Lower Rio Grande Valley of South Texas. Vehicle collisions are the greatest known source of mortality for ocelots in Texas. Crossing structures designed for ocelot use have been implemented throughout South Texas since the 1990s, however, ocelots rarely use them. We compared landscape characteristics between ocelot crossing structures and ocelot-vehicle collision sites. We quantified the spatial distribution of woody and herbaceous cover types surrounding ocelot crossing structures (n = 56) and ocelot-vehicle collision sites (n = 26) at multiple spatial extents and compared landscape metrics between these location types. The landscape surrounding ocelot crossing structures had 17–22% more open herbaceous cover >1,050 m from the road, and 1.2–5.8 ha larger herbaceous patches >450 m from the road compared to ocelot-vehicle collision sites. Additionally, many crossing structures installed during the 1990's are situated >100 km away from an extant ocelot population. Results from this study can guide conservation planners to place future road crossing structures in areas more likely to be used by ocelots. Our results also emphasize that reliable scientific data must be used for effective mitigation efforts. In the absence of data, post-installation assessments can improve the placement of future structures. [ABSTRACT FROM AUTHOR]

Rainfall is a strong driver of quail populations on southwestern rangelands and can account for a large portion (~70–95%) of the variability in regional quail production and abundance. Landowners have attempted to moderate these boom‐and‐bust fluctuations via management; however, presently it is unknown whether management can increase or stabilize quail populations in semiarid environments or whether rainfall remains as influential at small spatial extents. Our objectives were to evaluate the efficacy of management at mitigating the effects of rainfall on northern bobwhite (Colinus virginianus) populations on semiarid rangelands and to quantify the influence of rainfall on bobwhite density at smaller spatial extents. We conducted a study to evaluate these objectives during 2014–2020 in the Rio Grande Plains (n = 11 sites; 1,100‒6,500 ha) and Rolling Plains (n = 4 sites; 1,900‒4,000 ha) of Texas, USA. We estimated bobwhite density during late autumn (Dec‒Jan) on all sites using helicopter surveys within a distance‐sampling framework. We also obtained site‐level seasonal rainfall (Apr‒Aug) and quantified management intensity via landowner surveys and a scoring rubric to categorize sites into 3 classes (low, medium, and high management intensity). Bobwhite populations during this study experienced a boom‐bust cycle in both the Rio Grande Plains and Rolling Plains, with mean bobwhite density fluctuating considerably (0.57‒2.96 bobwhites/ha and 0.02‒2.88 bobwhites/ha, respectively). In the Rio Grande Plains, mean bobwhite density significantly increased from low to high management intensity in 2015 (1.12 ± 0.17 bobwhites/ha vs. 2.87 ± 0.39 bobwhites/ha, respectively), 2016 (1.06 ± 0.20 bobwhites/ha vs. 2.96 ± 0.36 bobwhites/ha, respectively), 2017 (0.73 ± 0.16 bobwhites/ha vs. 1.91 ± 0.32 bobwhites/ha, respectively), and 2019 (0.42 ± 0.14 bobwhites/ha vs. 1.01 ± 0.26 bobwhites/ha, respectively; P < 0.05). In addition, rainfall at the site level accounted for a low amount of the variation in bobwhite density (r2 = 0.09; P < 0.01). Similarly, in the Rolling Plains, mean bobwhite density significantly increased from low to high management intensity in 2015 (1.30 ± 0.27 bobwhites/ha vs. 2.20 ± 0.29 bobwhites/ha, respectively) and 2016 (1.26 ± 0.26 bobwhites/ha vs. 2.88 ± 0.34 bobwhites/ha, respectively; P < 0.05). Rainfall at the site level also accounted for a low amount of the variation in bobwhite density (r2 < 0.02; P = 0.82). Our findings suggest that management can increase bobwhite density beyond that of less‐managed properties but does not completely eliminate inter‐annual fluctuations in semiarid environments. In addition, rainfall appears to exert less of an influence on bobwhite density at a site level (e.g., 2,000 ha) than has been documented at a regional level (e.g., ≥8 million ha). [ABSTRACT FROM AUTHOR]

Non-native, invasive grasses can pose a threat to biodiversity in the southern U.S. Pennisetum ciliare (buffelgrass) is an example of an introduced invasive grass that has established in southwestern rangelands and negatively influenced biodiversity. Since its introduction, millions of hectares in the southwestern U.S. have been planted with, or invaded by, buffelgrass. Buffelgrass can form monocultures that not only reduce biodiversity but can also change ecosystem processes. Native-grassland restorations may be able to mitigate such negative impacts of non-native grasses. We conducted a study to document the response of herbaceous plants (grasses and forbs) and wildlife (grassland breeding birds, grassland wintering birds, and butterflies) to a 118-ha grassland restoration (involving prescribed fire, multiple discing and herbicide applications, and native-plant seeding) in La Salle County, Texas during 2013–2019. In general, we documented a numerical increase for all three taxa (native plants, birds, and butterflies) in species richness and relative abundance on the restoration site compared to a control. Our results suggest that native-grassland restoration is possible in a landscape dominated by buffelgrass. These restoration efforts can increase plant and wildlife diversity, although the time and expense required to achieve such responses are great. [ABSTRACT FROM AUTHOR]

Ecological light pollution is now recognized as a significant source of ecosystem alteration. We documented that holiday lights are a seasonal source of light pollution that constitute an ecological trap for eastern fox squirrels (Sciurus niger). Texas A&M University-Kingsville (TAMUK) wildlife students surveyed a 2-km walking transect 5 times per month each month for the relative abundance and diel behavior of eastern fox squirrels and feral cats (Felis catus) on the TAMUK campus during 2018-2019. Eastern fox squirrels exhibited diurnal behaviors throughout the year but extended their foraging behavior nearly 4 hours after sunset with the addition of holiday lights. Feral cats and owls (Strigiformes) exhibited diurnal and nocturnal behaviors but conducted the majority of their hunting during crepuscular hours. We documented that monthly squirrel mortality increased 7-fold with the addition of holiday lights, possibly due to the extension of foraging time by squirrels. Although seasonal lighting is intended to be festive for humans, it can have negative consequences for eastern fox squirrels. Educating the public concerning the issue of light pollution on wildlife species is needed because the majority of the public appears unaware that bright lights can negatively alter wildlife behaviors. Reducing light intensity by either using less outdoor lights or perhaps using colored lights rather than clear white bulbs may lessen the negative effect on foraging behavior of squirrels. [ABSTRACT FROM AUTHOR]

Montezuma quail (Cyrtonyx montezumae) inhabit oak (Quercus spp.)‐juniper (Juniperus spp.) woodlands throughout Mexico and the southwestern United States. In Texas, USA, Montezuma quail occur in the Edwards Plateau and Trans‐Pecos Mountains and Basins (Trans‐Pecos), 2 ecoregions with contrasting juniper patterns. Ashe juniper (Juniperus ashei) dominates in the Edwards Plateau and has been increasing over decades, whereas alligator juniper (Juniperus deppeana) is a co‐dominant in the Trans‐Pecos and appears to have stable Montezuma quail populations. Our objectives were to compare between ecoregions the relative abundance and habitat use of Montezuma quail in relation to juniper and quantify the influence of juniper on key features of Montezuma quail habitat (grass height, grass cover, forb cover, and forb species richness). We conducted a study from March–August 2018‒2020 in the Edwards Plateau (Kinney and Edwards counties) and Trans‐Pecos ecoregions (Jeff Davis County) to evaluate these objectives. We conducted call‐back surveys to estimate relative abundance (number of detections/hr) of Montezuma quail and identify used locations. We collected vegetation data at a micro‐scale (16‐m) at used (n = 32–30 points) and random locations (n = 70–60 points) in each ecoregion. Relative abundance of Montezuma quail was considerably lower in the Edwards Plateau (0.06 ± 0.01 detections/survey hr; x̅± SE) than in the Trans‐Pecos (1.10 ± 0.30 detections/survey hr). In addition, Montezuma quail selected areas of low Ashe juniper cover (<23% cover), density (<7 trees/80 m2), and height (<2 m) in the Edwards Plateau but selected areas of high alligator juniper cover (>18% cover), density (>4 trees/80 m2), and height (2–8 m) in the Trans‐Pecos. Moreover, Ashe juniper cover had a significant, negative influence on herbaceous features, whereas alligator juniper exerted little to no influence. Our results suggest that these 2 juniper species have contrasting effects on Montezuma quail space use and their habitat, possibly as a result of the contrasting influence of these junipers on herbaceous understory. Creating habitat for Montezuma quail in the Edwards Plateau generally will involve the reduction of Ashe juniper and creating patches that possess juniper trees of small stature (<2 m) with low amounts of cover (<23%) and density (<7 trees/80 m2), whereas management in the Trans‐Pecos will require site‐specific assessments based on current alligator juniper influence. © 2021 The Wildlife Society. [ABSTRACT FROM AUTHOR]

The northern bobwhite (Colinus virginianus; bobwhite) exists at the edge of its thermal tolerance in southern Texas, USA, a region characterized by extreme heat and periodic drought. Extreme heat and drought events are predicted to increase in frequency and intensity in semi‐arid regions, leading biologists to emphasize management of thermal cover. The degree to which temperatures within patches of woody vegetation vary and the specific vegetation structural characteristics that create cooler microclimates within these patches are unknown. We evaluated temperature variation between selected and available sites, vegetation characteristics facilitating cooler microsites, and whether these characteristics in addition to temperature were important predictors of microsite selection within woody patches. We radio‐tracked 83 bobwhites 2–3 times/week during April–August 2017–2018. We recorded operative and ground surface temperatures and measured woody and herbaceous vegetation height, canopy density, and overlapping woody and herbaceous cover at used and paired random locations. Within the same woody patch, 80% of used locations contained operative temperatures lower than or equal to random locations. There was a weak relationship between the vegetation variables we measured and temperature at paired locations, indicating that none of the vegetation variables alone can effectively reduce temperatures. Temperatures within woody patches are likely strongly tied to diurnal variation in solar angle and ability to create shade. Cooler temperatures, dense canopies, and overlapping woody vegetation had the greatest effects on relative probability of microsite use during the middle of the day, whereas warmer temperatures and taller woody vegetation had the greatest relative effects during the morning and evening. Our results suggest that temperature was influential across diurnal periods but foraging and predation avoidance may have also been important. Maintenance and preservation of dense woody vegetation and diverse shrub understories must be prioritized in habitat management for bobwhites in semi‐arid regions. © 2021 The Wildlife Society. Our study examined the vegetation characteristics creating suitable thermal refugia for northern bobwhites in southern Texas. Our results suggest that not all woody cover can serve as thermal cover, and managers must prioritize the preservation of microsites containing dense overhead canopies and overlap between woody plant species. [ABSTRACT FROM AUTHOR]

Context: Road networks can negatively impact wildlife populations through habitat fragmentation, decreased landscape connectivity, and wildlife-vehicle collisions, thereby influencing the spatial ecology and population dynamics of imperiled species. The ocelot (Leopardus pardalis) is a federally endangered wild felid in South Texas, with a high mortality rate linked to vehicle collisions. Objectives: Using a multi-scale approach, we quantified and examined landscape spatial structure at ocelot roadkill locations, and between roadkill locations of male and female ocelots. Methods: We quantified the spatial distribution of land cover types at 26 ocelot–vehicle collision sites in South Texas that occurred from 1984–2017. We compared landscape metrics of woody, herbaceous, and bare ground cover types across multiple spatial scales at roadkill locations to those from random road locations, and between male and female ocelots. Results: Roadkill sites consisted of 13–20% more woody cover than random locations. Woody patches at roadkill sites were 7.1–11% larger (2.4 ha) closer to roads and spaced 10–16 m closer together farther away from roads compared to random locations. Percent woody cover was the best indicator of ocelot–vehicle collision sites; there were no differences in woody cover between male and female road mortality locations. Conclusion: These findings suggest that ocelots are likely struck by vehicles while crossing between habitat patches. Roads that bisect areas of woody cover have negative impacts on ocelots by increasing habitat fragmentation and vulnerability to vehicle collisions. Crossing structures should be placed in areas with ≥ 30% woody cover and 3.5 ha woody patches. [ABSTRACT FROM AUTHOR]

Populations of northern bobwhites (Colinus virginianus; hereafter bobwhite) have been declining across their geographic range in North America, prompting consideration of the role parasites may play. We conducted this study to learn about the helminth fauna in South Texas, a region that supports a sustainable bobwhite population. Helminths were examined from 356 bobwhites collected during the 2014–2015 (n = 124) and 2015–2016 (n = 232) hunting seasons, when increasing trends in precipitation were observed in comparison with the previous two years. Ten helminth species were found, consisting of 14,127 individuals. Of these, all are heteroxenous parasites and three are pathogenic (Dispharynx nasuta, Tetrameres pattersoni and Oxyspirura petrowi). Aulonocephalus pennula numerically dominated the component community (81% prevalence, 99% of the total helminths found), whereas each of the remaining species occurred rarely (≤9% prevalence) and contributed few individuals (≤0.4%) to the helminth community. Prevalence and abundance of A. pennula were not influenced by host age, sex or body mass, but abundance was higher during the 2014–2015 than the 2015–2016 hunting season. Our findings indicate that the helminth community in bobwhites from South Texas can vary during long-term, highly variable precipitation conditions and these communities are more similar to those found in the Rolling Plains of Texas than those found in the eastern part of the bobwhite's geographic range in the US. [ABSTRACT FROM AUTHOR]

Sympatric ocelots (Leopardus pardalis) and bobcats (Lynx rufus) in South Texas show substantial overlap in body size, food habits, and habitat use. Consequently, we explore whether temporal niche partitioning may explain ocelot and bobcat coexistence. We investigated the influence of sun angle, lunar illumination, and maximum diurnal temperature on temporal movement rates of sympatric ocelots (n = 8) and bobcats (n = 6) using a combination of high-frequency GPS locations and bi-axial accelerometer data. We demonstrated that accelerometer data could be used to predict movement rates, providing a nearly continuous measure of animal activity and supplementing GPS locations. Ocelots showed a strong nocturnal activity pattern with the highest movement rates at night whereas bobcats showed a crepuscular activity pattern with the highest movement rates occurring around sunrise and sunset. Although bobcat activity levels were lower during the day, bobcat diurnal activity was higher than ocelot diurnal activity. During warmer months, bobcats were more active on nights with high levels of lunar illumination. In contrast, ocelots showed the highest nocturnal activity levels during periods of low lunar illumination. Ocelots showed reduced diurnal activity on hotter days. Our results indicate that ocelot and bobcat coexistence in South Texas can be partially explained by temporal niche partitioning, although both felids showed periods of overlapping activity during nocturnal and crepuscular periods. [ABSTRACT FROM AUTHOR]

One hundred and sixty-one northern bobwhites (Colinus virginianus ; hereafter 'bobwhite') were examined from the Rolling Plains ecoregion of Texas and western Oklahoma from 2011 to 2013. Complete necropsies yielded 13 species, of which two are new host (Gongylonema phasianella) and region (Eucoleus contortus) records and three (Dispharynx nasuta , Tetrameres pattersoni and Oxyspirura petrowi) are known to cause morbidity and mortality. Of the species found, Aulonocephalus pennula commonly occurred, Oxyspirura petrowi was intermediate in prevalence, and the remaining species were rare. Species richness was similar compared to studies from the southeastern U.S., but higher than studies from the same region. In addition, 12 of the 13 species were heteroxenous helminths, supporting the theory that heteroxenous helminths in semi-arid regions are more successful than monoxenous helminths. Prevalence and abundance of A. pennula and O. petrowi were higher in adult bobwhites than in juveniles. Abundance of A. pennula and O. petrowi was higher at southern locations compared to northern locations in the study area. Our study is the first to provide a current assessment of the bobwhite helminth community across the Rolling Plains ecoregion of the U.S. [ABSTRACT FROM AUTHOR]

Visual methods of species identification are used both in research and recreational contexts because they are inexpensive, non-invasive, and believed to be effective among uniquely identifiable individuals. We examined the ability of the general public to identify live snakes (Serpentes) that are native to the United States using an online snake identification search engine (SISE) produced by the North America Brown Tree Snake Control Team (NABTSCT) website, http://www.nabtsct.net. The SISE consisted of participants answering 7 descriptive questions concerning a snake and then reviewing photographs of snakes that matched that description. Using 3 species of snakes native to Texas, USA, 21% of 395 participants were able to correctly identify all of the snakes using the online SISE, 54% correctly identified 2 snakes, 18% correctly identified 1 snake, and only 7% could not identify any snakes. Participants identified the distinctly marked checkered garter snake (Thamnophis marcianus) more readily (87% of participants) than the gopher snake (Pituophis catenifer) and Trans-Pecos rat snake (Bogertophis subocularis; 55% and 46% of participants, respectively). The probability of participants correctly identifying a snake using the online SISE increased substantially if ≥4 of the 7 descriptive questions were answered correctly. The age of participants and affinity toward snakes affected participant ability to correctly answer questions about snake morphology and identify snakes. In general, participants who displayed fear of snakes were less likely to correctly identify snake species than those who expressed a snakeneutral or enthusiast attitude. Additionally, younger participants performed better, on average, than older participants. Most participants (97%) claimed they would be able to use the online SISE to correctly identify other snakes in the future. We believe the public can use the online SISE to identify snakes, and hence, it can be an educational tool for the public to learn about an often neglected wildlife suborder. [ABSTRACT FROM AUTHOR]

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The population rebound of the American alligator (Alligator mississippiensis; hereafter, alligator), with the rapid growth of populations throughout its range, has caused an influx of human-alligator conflicts. We quantified 5,838 nuisance alligator reports from 2000 to 2011 to develop more site-specific strategies of management and to determine where management should be focused to minimize the conflict. We also surveyed the general public's attitude toward and knowledge of alligators (n = 98) as a technique to better understand human dimensions of nuisance alligator management in Texas. Counties that received the largest numbers of nuisance alligator reports were Jefferson (16%), Fort Bend (14%), Matagorda (11%), Brazoria (10%), Harris (7%), Jackson (5%), Orange (5%), Chambers (5%), Calhoun (5%), and Liberty (3%) counties. We found that of the nuisance alligators reported, 45% were male, 18% were female, and 38% were reported as unknown. Most residential situations occurred in Fort Bend County, while more roadway and worksite situations occurred in Jefferson County, and more livestock depredation occurred in Matagorda County. Conflict resolution differed by alligator size. Most (41%) alligators <1.5 m in length were relocated, and most (66%) alligators >1.5 m in length were removed through lethal means. Most (93%) survey responders would support an alligator removal program that conducted capture and relocation, but they were unwilling to have alligators relocated near their homes. Only 15% of survey responders would support an alligator management program that utilized lethal removal. Visitors with more education (bachelor's degree or higher) were more willing to support lethal control of alligators. We determined that survey responders had some knowledge of alligators and that an alligator educational program targeted to residents of the northern Texas Gulf Coast could help reduce the number of human-alligator conflicts. [ABSTRACT FROM AUTHOR]

Managing highway rights-of-way (HROW) for safety depends upon the annual precipitation received and vegetation mowing practices. This study was conducted along a precipitation gradient in Texas, USA, to evaluate how precipitation and mowing treatments influence vegetation heights. The experiment was initiated in spring 1999 and completed in autumn 2002. Each site had ten treatments with four replications and consisted of forty 15 m × 6 m subplots. Commercial highway mowing equipment was used to mow the subplots at 5-, 10-, or 20-cm heights with an annual mowing frequency of one, two, or three times per year and a non-mowed control. A vegetation height of >30 cm is generally considered a safety hazard. Control subplot vegetation heights increased along the annual precipitation gradient. Most of the subplot vegetation heights at the more arid Andrews site (35 cm precipitation year) were <30 cm. Subplot vegetation heights at the Tahoka (50 cm precipitation year), Brady (66 cm precipitation year), and Lufkin (109 cm precipitation year) locations exceeded 30 cm, regardless of mowing frequency or height. Mowing treatments for HROW safety must be based on site-specific conditions. In areas that receive <35 cm precipitation year, mowing treatments have little effect on vegetation height, and management practices do not necessarily affect visual safety. In areas that receive >35 cm precipitation year, mowing three or less times per year, regardless of mowing height, makes it unfeasible to maintain the vegetation heights of <30 cm needed to maintain the HROW visual safety criterion. [ABSTRACT FROM AUTHOR]

Arid and semiarid rangelands are suitable for responsible biosolids application. Topical application is critical to avoid soil and vegetation disturbance. Surface-applied biosolids have long-lasting effects in these ecosystems. We conducted a 10-year research program investigating effects of biosolids applied at rates from 0 to 90 dry Mgha-1 on soil water infiltration; runoff and leachate water quality; soil erosion; forage production and quality; seedling establishment; plant physiological responses; nitrogen dynamics; biosolids decomposition; and grazing animal behavior and management. Biosolids increased soil water infiltration and reduced erosion. Effects on soil water quality were observed only at the highest application rates. Biosolids increased soil nitrate-nitrogen. Biosolids increased forage production and improved forage quality. Biosolids increased leaf area of grasses; photosynthetic rates were not necessarily increased by biosolids. Biosolids effects on plant establishment are expected only under moderately favorable conditions. Over an 82-mo exposure period, total organic carbon, nitrogen, and total and available phosphorus decreased and inorganic matter increased. Grazing animals spent more time grazing, ruminating, and resting in biosolids-treated areas; positive effects on average daily gain were observed during periods of higher rainfall. Our results suggest that annual biosolids application rates of up to 18Mg ha-1 are appropriate for desert rangelands. [ABSTRACT FROM AUTHOR]

Prescribed fire is a common land management tool used to reduce undesirable shrubs, improve forage quality, and enhance wildlife habitat for game species. However, it also has impacts on nongame species. We examined whether a prescribed fire would affect the abundance of lizards and invertebrates in central Texas. In February 2004, four sites were treated with low-intensity prescribed fires; four adjacent non-burned sites served as controls. Vegetation structure (litter depth, percent canopy cover, visual obstruction) and foliar cover were recorded prior to and seasonally following the burn. Lizards and potential invertebrate prey were collected from all plots between March and August 2004 (152 traps, 5908 trap nights). Lizard numbers were not significantly (P > 0.312) affected by the fire, nor were their potential prey or habitat greatly affected. Burning reduced numbers of Homoptera (P < 0.031), and Diptera were more abundant in burned plots in May (P < 0.002), but no other effects were detected (P <0.05 for all other taxa). Burning did not affect vegetation structure (P > 0.25 for all measures); however, foliar cover of Texas wintergrass was lower in burned plots in March but recovered to non-burned levels by May. Our results suggest that small-scale, low-intensity fires have minimal impact on central Texas lizards, the vegetation structure of their habitat, or the invertebrates of their diet. [ABSTRACT FROM AUTHOR]

Black bears (Ursus americanus) began recolonizing the Trans-Pecos region of Texas from Mexico in the late 1980s after a 30-year absence. This region is predominately a ranching community and knowledge of landowner attitudes is essential to development of management plans for this population. We surveyed 1,100 landowners in the region to measure their response toward the natural recolonization of black bear in the Trans-Pecos. More positive scores toward black bear recolonization came from younger, more educated landowners who had owned land for less than three generations. Of the landowners against recolonization most (52%) believed that livestock losses would be excessive. Managers would benefit by focusing their efforts on increasing awareness of methods for preventing black bear damage to landowners with negative attitudes and those owning large parcels (>4,048 ha) of land possibly containing potential bear habitat. It is important that managers consider and incorporate landowners when managing this increasing black bear population. [ABSTRACT FROM AUTHOR]

Some diurnal raptors are frequently observed at prairie dog (Cynomys sp.) colonies. As a result, some military installations have conducted prairie dog control activities to reduce the bird-aircraft strike hazard (BASH) potential of low-flying aircraft. To evaluate the validity of this management strategy, we assessed raptor associations with prairie dog colonies at 2 short-grass prairie study areas: southern Lubbock County, Texas, USA, and Melrose Bombing and Gunnery Range in east-central New Mexico, USA. We quantified diurnal raptors (i.e., Falconiformes) at plots occupied (colony plots) and unoccupied (noncolony plots) by black-tailed prairie dogs (Cynomys ludovicianus) at both sites throughout 2002. We compared the number of individual birds of a given species at colony and noncolony plots within each study area by season. Ferruginous hawks (Buteo regalis) and northern harriers (Circus cyaneus) were more abundant at colony plots, whereas Swainson's hawks (B. swainsoni) and American kestrels (Falco sparverius) were more abundant at noncolony plots. Red-tailed hawk (B. jamaicensis) abundance did not differ between the 2 plot types. Our results suggest prairie dog control as a method of reducing BASH potential may be effective at some sites but may be ineffective or even increase the BASH potential at others. Thus, bird-avoidance models assessing the BASH potential should be conducted on a site-specific basis using information on relative and seasonal abundances of individual raptor species and the relative strike risks they pose to aircraft. [ABSTRACT FROM AUTHOR]

Examines the effect of two- to seven-year exposure times on the composition of single applications of biosolids in western Texas. Reason behind the total organic C decrease; Loss of copper and zinc from biosolids through leaching or runoff.

The application of unmanned aerial vehicles (UAVs) in the monitoring and management of rangelands has exponentially increased in recent years due to the miniaturization of sensors, ability to capture imagery with high spatial resolution, lower altitude platforms, and the ease of flying UAVs in remote environments. The aim of this research was to develop a method to estimate forage mass in rangelands using high-resolution imagery derived from the UAV using a South Texas pasture as a pilot site. The specific objectives of this research were to (1) evaluate the feasibility of quantifying forage mass in semi-arid rangelands using a double sampling technique with high-resolution imagery and (2) to compare the effect of altitude on forage mass estimation. Orthoimagery and digital surface models (DSM) with a resolution <1.5 cm were acquired with an UAV at altitudes of 30, 40, and 50 m above ground level (AGL) in Duval County, Texas. Field forage mass data were regressed on volumes obtained from a DSM. Our results show that volumes estimated with UAV data and forage mass as measured in the field have a significant relationship at all flight altitudes with best results at 30-m AGL (r2 = 0.65) and 50-m AGL (r2 = 0.63). Furthermore, the use of UAVs would allow one to collect a large number of samples using a non-destructive method to estimate available forage for grazing animals. [ABSTRACT FROM AUTHOR]

We studied breeding season communities of grassland birds on short-grass and mixed-grass prairie sites during the second and third breeding seasons following two large wildfires in March 2006 in the Texas panhandle, USA. There was an apparent temporary shift in avian community composition following the fires due to species-specific shifts associated with life-history traits and vegetation preferences. Species that prefer sparse vegetation and bare ground on short-grass sites, such as Homed Lark (Eremophila alpestris), benefited from wildfires, while others, such as Western Meadowlark (Sturnella neglecta), that prefer more dense vegetation, were negatively impacted. Mixed-grass sites had species-specific shifts in 2007, two breeding seasons after the fires; grassland bird communities on burned plots were similar by 2008 to those on unburned plots. Avian communities appeared to return to pre-burn levels within 3 years following wildfires. Many of the responses in our study of wildfire were similar to those reported following prescribed fires elsewhere. Prescribed fires appear to have similar effects on the avian community despite differences in intensity and environmental conditions during wildfires. [ABSTRACT FROM AUTHOR]

Abstract Invasive plants are a serious concern throughout many rangelands in North America because of their detrimental effects on vegetation community composition, diversity and wildlife habitat. Growing evidence shows that invasive plants affect ecosystem processes such as energy and nutrient cycling and soil microbial associations. Tanglehead (Heteropogon contortus [L.] P. Beauv. ex Roem and Schult.) is a C 4 , perennial caespitose grass that is rapidly increasing throughout the Coastal Sand Plain in southern Texas. In a field study, we examined the response of soil microbial community size and structure over a 3-year period (2013–2015) along a tanglehead invasion gradient represented by the natives-without-tanglehead plant communities (<15% tanglehead), natives-with-tanglehead mixtures (15–70% tanglehead), and tanglehead-dominated (>70% tanglehead) plant communities. Soil microbial size [microbial biomass carbon (MBC), nitrogen (MBN), and total fatty acid methyl esters (FAME)] differed between natives-without-tanglehead and tanglehead-dominated sites in 2013 and 2015 (dry years). MBC averaged ~200 mg kg−1 soil in natives-without-tanglehead sites but <70 mg kg−1 soil in invaded sites, and total FAME averaged 36 and 41 nmol g−1 soil in native-without-tanglehead and invaded sites, respectively, in 2013 and 44 and 55 nmol g−1 in 2015. Invaded sites had higher saprophytic fungi:bacteria ratios than sites with <15% tanglehead (0.64 vs. 0.53) over all 3 years. We conducted a separate inoculation experiment where tanglehead was planted in native soils that lacked tanglehead to investigate effects of tanglehead inoculation on soil microbial community dynamics; introduction of tanglehead to native soils did not change microbial community structure, size, or relative abundance of key microbial FAME indicators over the course of 18 months. Field study results revealed different soil microbial communities associated with tanglehead, but at what point these communities change during invasion is not clear, and how these effects are related to overall habitat degradation associated with this invasive plant requires further study. [ABSTRACT FROM AUTHOR]

Falco sparverius (American Kestrel) and Lanius ludovicianus (Loggerhead Shrike) have undergone major population declines, which may be partially due to habitat changes on their wintering grounds. The objectives of this study were to compare quantitative habitat metrics and landcover data at sites used by American Kestrels and Loggerhead Shrikes during the winter. We conducted this study by observing individuals of both species along private and public roads across 8 counties in South Texas and recording GPS coordinates and various habitat characteristics at each location. We calculated woody canopy cover by digitizing all woody cover within 100 m of the sighting locations and at random points, and obtained landcover data from the National Land Cover Database (NLCD) for 2001 and 2011. Female American Kestrels were associated with shorter herbaceous height (median = 7.4 cm) than male American Kestrels (16.4 cm) or Loggerhead Shrikes (13.6 cm). Woody canopy cover was lower around sites used by female American Kestrels (q0.9 = 1.9%), compared to sites used by male American Kestrels (q0.9 = 17.8%), Loggerhead Shrikes (q0.9 = 21.3%), or at random points (q0.9 = 51.6%). Although cultivated crops were the most common cover type within 100-m radius buffers of each species group, this cover type was more abundant (73.2% ± 1.5) in sites used by female American Kestrels than sites used by male American Kestrels (47.7% ± 4.1) or Loggerhead Shrikes (41.1% ± 2.7). In contrast, sites used by female American Kestrel had lower amounts of pasture/hay, grassland/ herbaceous, and shrub/scrub types compared to those used by male American Kestrels or Loggerhead Shrikes. Two of the most important cover classes for American Kestrels and Loggerhead Shrikes, cultivated crops and pasture/hay, still comprised 26.0% (481,882 ha) and 22.3% (413,396 ha) of these 8 South Texas counties in 2011, but had decreased by 0.77% and 0.84% since 2001. Medium- and high-intensity development has increased, for a total of 3360 ha (15.49% change), over the same timeframe. Slowing the loss of these favorable open-cover habitat types should be a priority for the conservation of American Kestrels and Loggerhead Shrikes in South Texas. [ABSTRACT FROM AUTHOR]

Soil disturbances that accompany energy development can damage local habitats. Prior to oil and gas extraction, it is commonly recommended that topsoil stockpiles be created to aid future restoration. Our study area, a retired fracking pond in the western Rio Grande Plains, Texas, was restored in 2017 with stockpiled topsoil that was collected in 2013. We segregated the existing stockpile into three layers that were ∼1.5 m in thickness and distributed these layers, along with a non-amended control surface (consisting of former subsoil that made up the perimeter of the fracking pond), in strips over the restoration area. Each of the four surfaces was seeded with a mixture of (1) 13 native grasses, (2) 13 native grasses plus an annual warm-season grass cover crop, or (3) non-seeded. We monitored plant density and species composition two through five years post-restoration. The non-amended control surface had higher seeded grass density during the final 2 sampling periods; stockpiled surfaces seldom differed from each other. Previous year's competing plant density had little effect on restoration success. Providing supplemental seed initially increased seeded plant density but benefits diminished over time; adding a cover crop was not advantageous. Changes in community composition over time were similar on stockpile surfaces but more variable than observed on the control surface. Results suggest that stockpiling topsoil may not be necessary, but that supplemental seeding was beneficial, to restoration success. • Energy extraction affects ecosystems by disturbing topsoils and plant communities • We monitored vegetation on a retired fracking pond in years 2–5 post-restoration • Stockpiling topsoils for future restoration may not enhance restoration success • Seeding locally-adapted native grasses promotes restoration success [ABSTRACT FROM AUTHOR]

Geomys personatus maritimus (Maritime Pocket Gopher) is a genetically distinct subspecies that only occurs in deep sandy soils of Nueces and Kleberg counties of southern Texas. The US Fish and Wildlife Service has considered recommending the Maritime Pocket Gopher for federal listing. Because a large proportion of this gopher’s current range occurs on US Navy (hereafter, Navy) property, active management by the Navy plays a key role in the conservation of this subspecies. Therefore, our objective was to assess the distribution and habitat preferences of Maritime Pocket Gophers on Navy properties in southern Texas. We conducted a strip-transect survey to evaluate the number and distribution of gopher mounds on the Navy base. We created GIS layers of the different disturbance types and plant communities, and overlaid them onto the mapped gopher-mound density layer. If the proportion of available area used by Maritime Pocket Gophers was below or above the corresponding 90% confidence interval, we categorized disturbance types and plant communities as used more often or less often, respectively. The distribution of Maritime Pocket Gophers was influenced by soil-particle size, plant community, type of habitat disturbance, and quantity of leaf litter. Maritime Pocket Gophers favored areas with sandy soil in frequently mowed native prairie, restoration fields, and Cynodon dactylon (Bermuda Grass) with little to no ground litter (i.e., dead vegetation, debris). [ABSTRACT FROM AUTHOR]