Adaptive Management and Quail Conservation on Rangelands in the American West

Adaptive management has been and is being practiced with the goal of sustaining populations of wild quails on large areas of rangelands in the American West. Because the current land use practices throughout most of the eastern two-thirds of the United States largely do not promote early-successional vegetation communities, rangelands contain the largest remaining blocks of contiguous (unfragmented) habitat for the northern bobwhite (Colinus virginianus) and the other 5 species of quails found in the western states. Many wildlife professionals on both private and public rangelands are practicing a diverse array of quail habitat and population management actions that could be considered a form of adaptive management—an iterative process used to make decisions in the context of uncertainty. Though this “learning by doing” approach is not always formally labeled adaptive management, these wildlife professionals intuitively recognize the value of the process in sustaining populations of wild quails. We support our assertions about adaptive management with 4 case study examples of adaptive management projects that promote quail conservation—including quail hunting—on both private and public rangelands in the American West. By discussing these scenarios within an adaptive management framework, we hope to highlight current and future opportunities for adaptive management in quail conservation on rangelands and to discuss where adaptive management may be improved or no longer be appropriate

Atubular glomeruli in a rat model of polycystic kidney disease

Atubular glomeruli in a rat model of polycystic kidney disease.BackgroundAutosomal-dominant polycystic kidney disease (ADPKD) is associated with a progressive decline in glomerular filtration rate (GFR) that often leads to end-stage renal disease. The basis for this decline in GFR is poorly understood.MethodsGlomeruli in heterozygous Han:SPRD rats with ADPKD and their normal litter mates were studied by light microscopy, using serial sectioning techniques. The connections of the renal corpuscles to proximal tubules were classified as normal, atrophied, or absent (atubular glomerulus). Renal corpuscles also were examined by scanning electron microscopy. Single nephron glomerular blood flows were determined using microspheres.ResultsIn the kidneys of six-month-old rats with ADPKD, 50% of the glomeruli were atubular and another 26% were associated with atrophied neck segments; these glomeruli were most often smaller in size than normal. About 16% of the glomeruli were hypertrophied and had normal connections to proximal tubules. Sclerotic changes in cystic kidney glomeruli were usually mild or moderate, and belied the failure of glomerular function. Glomerular blood flow in the cystic kidneys averaged half of normal and was markedly heterogeneous; the majority of small glomeruli displayed very low blood flows and a few showed relatively high blood flows. Fewer glomerular abnormalities were found in rats treated for five months with potassium citrate in their drinking water.ConclusionsThe diminished GFR in the rat with ADPKD can be accounted for largely by the formation of atubular glomeruli. Compensatory glomerular hypertrophy also is present and may contribute to the progression of the renal disease

Comparison of Dog Surveys and Fall Covey Surveys in Estimating Fall Population Trends of Northern Bobwhite

The use of fall covey surveys to monitor population trends for northern bobwhite (Colinus virginianus; hereafter bobwhite) have been widely used in bobwhite research. Estimates of relative abundance from this monitoring technique are often important in assessing population responses to management practices or annual variation. However, conducting covey call surveys is labor intensive and typically can only be conducted during a narrow time frame. The use of dogs as a research tool may offer an efficient alternative to monitor bobwhite population trends. While dogs have been used in research for many other gallinaceous species, their application for bobwhite has received minimal research. To compare traditional and novel (dog) methods for both relative population abundance and density estimation, we conducted covey call surveys (50 points) and dog transects (32 km) during the fall (Sep-Oct) season from 2012-2014 at Beaver River WMA, Beaver County, Oklahoma, USA. A total of 306 detections were observed through fall covey count surveys, while only 44 detections were observed through dog transect surveys. Fall covey surveys yielded indices of 1.45, 2.04, and 3.21 detections per point count during 2012, 2013, and 2014, respectively. Dog transects yielded 0.23, 0.34, and 0.67 detections per km during 2012, 2013, and 2014, respectively. A Pearson’s correlation coefficient of 0.996 indicated high correlation between indices estimated between both survey methods. However, the low sample size for detections during dog surveys precluded any analysis that would yield bobwhite density estimates. Our results indicate that dog transects can be a method for estimating abundance indices for bobwhite. However, if estimates of bobwhite densities are of interest, then use of dog transect surveys are not recommended as only under high quail densities or with high observer efforts do enough detections accumulate for robust density estimation unless large effort is expended

Northern Bobwhite Survival Related to Movement on a Reclaimed Surface Coal Mine

Reclaimed coal mines represent opportunity to provide large tracts of early succession habitat essential to northern bobwhite (Colinus virginianus) populations. However, little research has been conducted to explore the potential of reclaimed mine sites and examine bobwhite ecology on these unique areas. Reclaimed mines in Kentucky were planted to non-native species, such as sericea lespedeza (Lespedeza cuneata) and tall fescue (Festuca arundinacea), which do not provide suitable structure for northern bobwhite brood-rearing and movement. Fallow disking (in blocks and linear firebreaks) and planting food plots are part of current management efforts to improve food availability and habitat structure for broods. We trapped and radiomarked 266 northern bobwhites between April 2010 and September 2011 on Peabody Wildlife Management Area, a 3,330-ha reclaimed coal mine in western Kentucky, USA to investigate the effects of current management practices on movement and survival. We calculated seasonal daily movement as the Euclidean distance from a location on day 1 to day 2. Breeding season (1 Apr-30 Sep) movement averaged 128 m in 2010 and 147 m in 2011. Daily movement averaged 163 m during the 2010–2011 non-breeding (1 Oct-31 Mar) season. Multiple regression analysis indicated annual food plots, disk blocks, firebreaks, and roads did not explain variation within daily movement regardless of season (R2 0.04). Individual bird/covey, precipitation, hours between locations, and average temperature also poorly explained movement variation. We used Program MARK to model the effect of season, year, mean daily movement, mean distance to annual food plots, disk blocks, firebreaks, and roads on survival. The season (breeding/non-breeding) model explained 81% of the variation in survival, and the year model explained 13%, suggesting management was not driving survival. We do not believe disking should be discontinued, although it did not influence movement, as it can improve vegetation structure important to nest-site selection and broods

Proximal tubule morphology after single nephron obstruction in the rat kidney

Proximal tubule morphology after single nephron obstruction in the rat kidney. This study examined the effects on proximal tubule morphology of blocking single nephrons with paraffin wax for one day, one week, or one month in the rat. Proximal tubule lumens were blocked with a short column of wax using micropuncture. Chronically blocked and control (normal) tubules were fixed by either intravascular or intraluminal perfusion of glutaraldehyde solution. Proximal tubule segments down-stream to the wax block were examined by light and transmission electron microscopy. Intraluminal Alcian blue dye, serial sectioning, and nephron microdissection techniques were used to identify nephrons. One day after obstruction, all proximal tubule cells downstream to the block were injured. Some recovery was seen. S1 and S2 segments showed more severe damage than S3 segments. Alcian blue, which normally is excluded from cells, entered the cytoplasm of some damaged S1-S2 cells. After one week of obstruction, the tubule appeared to have reconstituted itself, but cells were less differentiated than normal. One month after obstruction, blocked tubules were atrophied. Tubule cells were simplified and were surrounded by a thickened basement membrane. The results suggest that prolonged proximal tubule blockade produces injury and atrophy of the proximal tubule probably due to ischemia and interruption of normal reabsorptive activity

Northern Bobwhite and Fire: A Review and Synthesis

Our understanding of the relationship between northern bobwhite (Colinus virginianus; hereafter, bobwhite) and fire began with Herbert Stoddard’s work in the early 20th century. Research on the topic has continued, but our application of fire is deeply rooted in Stoddard’s work, even as it has become evident that fire regimes must be adapted to variable environmental conditions that are evolving with a changing landscape and climate. A comprehensive review and synthesis of the literature on this topic would help formalize research advancements since Stoddard and identify knowledge gaps for future research. Results from experiments suggest fire creates favorable local habitat conditions for bobwhite such as plant composition, bare ground, and plant structure. Frequent prescribed fire is closely tied to where bobwhite populations are at their greatest (e.g., Red Hills region of Georgia and Florida, USA). However, an empirical gap exists between patch-level conditions and the bobwhite-landscape ecology interface. For example, it is well established that a 2-year fire return interval in pine savanna ecosystems with fertile soil is best for bobwhite. But causal evidence is limited for areas of different soil types, precipitation, and past land use across the bobwhite range. We review the extant literature describing prescribed fire use for bobwhite management, focusing on documented effects of fire on life-history characteristics of bobwhite under different environmental conditions. Habitat outcomes of fire management depend on fire frequency, seasonality, scale, and interaction with other management, and different strategies should be employed depending on the environment and desired effects. Adaptive management strategies will be necessary to address the challenges of rising temperatures associated with a changing climate, which are likely to alter the conditions under which burns occur and increase the difficulty of meeting basic burn criteria. Positive public attitudes toward prescribed fire will be key to developing a policy and management framework that supports efficient prescribed fire application. Our review elucidates range-wide processes and patterns to better inform the site-specific application of fire

Survival of Radio-Marked Versus Leg-Banded Northern Bobwhite in Kentucky

Understanding the impact of radiomarking northern bobwhite (Colinus virginianus) survival is essential because of the widespread reliance on radiotelemetry to assess vital population parameters. We conducted an assessment of bobwhite populations within the Central Hardwoods Bird Conservation Region using leg banding and radiotelemetry on Peabody Wildlife Management Area, a 3,330-ha reclaimed surface mine in western Kentucky. We captured bobwhites using baited funnel traps during a 112-day period (23 Jul-11 Nov 2010) and marked 180 with necklace-style radio-transmitters (6 g) and 256 birds with only leg bands. Eighty-five birds were opportunistically recaptured in funnel traps, of which 81 were used in developing survival estimates. We used the Cormack-Jolly-Seber model in Program MARK to estimate periodic survival rates (PSR) of both sample groups. Candidate models which included body mass as a covariate explained the most variability in survival. The estimated PSR was 0.309 6 0.109 based on the best approximating model and was 0.302 6 0.108 from model averaging. We calculated a point of inflection for this model, which suggested a mass ‘threshold’ of 131g, above which survival improved at a decreasing rate. The model including only the radio-transmitter effect had a DAICc .3 and was considered to be non-plausible. Further research with larger samples is needed to develop more robust survival models to fully assess the effects of radiomarking bobwhites. It does not appear, based on our study, that radio transmitters adversely affect survival of northern bobwhite

Does the presence of oil and gas infrastructure potentially increase risk of harvest in northern bobwhite?

Beyond organisms experiencing direct impacts (mortality) from the presence of anthropogenic features, interactive relationships may exacerbate the effects of anthropogenic disturbance within the context of these features. For example, mortality risk may be affected by the road infrastructure associated with energy development by influencing space use of predators including human hunters. To assess these relationships, we conducted research on northern bobwhite Colinus virginianusacross a hunted and non-hunted area of Beaver River Wildlife Management Area, Oklahoma, using radiotelemetry from 2012–2015. We found that bobwhite mortality risk decreased as the distance from primary roads (m) increased across weeks (hazard ratio [HR] = 1.008, 95% confidence interval [CI] = 1.0003 to 1.0013). The interaction between unit (hunted and non-hunted) and distance from primary roads was not significant (HR = 1.00, 95% CI = 0.999 to 1.001) indicating that hunting pressure was not a likely explanation for the observed decrease in survival related to primary roads. Bobwhite on the hunted unit avoided exposed soil/sparse vegetation ( = -0.01, CI = -0.02 to -0.002) and bare ground ( =-0.01, CI =-0.02 to -0.002) more than bobwhite on the non-hunted unit, however these were weak relationships. No other differences in bobwhite space use were detected related to hunting. Though we were limited to estimating theoretical rather than empirical amounts of hunting pressure during our study, we were unable to detect any negative compounding effects of anthropogenic development and hunting pressure on bobwhite ecology during the hunting season

Invasive woody plants as foci of tick-borne pathogens: Eastern redcedar in the southern Great Plains

Habitat preference and usage by disease vectors are directly correlated with landscapes often undergoing anthropogenic environmental change. A predominant type of land use change occurring in the United States is the expansion of native and non-native woody plant species in grasslands, but little is known regarding the impact of this expansion on regional vector-borne disease transmission. In this study, we focused on the impact of expanding eastern redcedar (Juniperus virginiana; ERC) and tested two hypotheses involving relationships between habitat preferences of adult tick species in rural habitats in central Oklahoma. Using CO2 traps, we collected ticks from two densities of ERC and grassland and screened adult ticks for the presence of pathogen DNA. We found support for our first hypothesis with significantly more Amblyomma americanum (Linnaeus) and Dermacentor variabilis (Say) collected in ERC habitats than in grassland. Our second hypothesis was also supported, as Ehrlichia-and Rickettsia-infected A. americanum were significantly more likely to be collected from ERC habitats than grassland. As the first evidence that links woody plant encroachment with important tick-borne pathogens in the continental United States, these results have important ramifications involving human and companion animal risk for encountering pathogen-infected ticks in the southern Great Plains.Peer reviewedEntomology and Plant PathologyNatural Resource Ecology and Managemen

Monitoring Northern Bobwhite Breeding Populations in the Central Hardwoods Bird Conservation Region

Monitoring northern bobwhite (Colinus virginianus) breeding populations is an important component of the National Bobwhite Conservation Initiative as a means of evaluating success of achieving population goals. Northern bobwhite populations declined by 3.8% from 1980 to 2006 in the Central Hardwoods Bird Conservation Region (CHBCR). Northern bobwhite research in the CHBCR is limited and population trend estimates are based on North American Breeding Bird Survey (BBS) data. Monitoring northern bobwhite populations and developing accurate population estimates by incorporating detection functions and occupancy estimates are important components of the conservation initiative in this region. We documented northern bobwhite abundance throughout the CHBCR via a roadside-based removal and distance sampling survey method, and assessed differences in detection with respect to observer, northern bobwhite relative abundance, and land cover. We also addressed the potential for a roadside survey bias to ascertain if there was a seasonal, or site effect on northern bobwhite detection and occupancy through repeated surveys. Finally, we measured northern bobwhite calling rates by time of day and day of the breeding season to assess bobwhite availability for detection with radiotelemetry data. The spatially-balanced, roadside, monitoring strategy used counties as basic sampling units within bobwhite focal areas in the CHBCR (n 1⁄4 37 counties). We randomly located 5, 15-km monitoring routes in each focal county along secondary roads. We conducted 5-min unlimited distance point counts along each route (30 counts/route) from May through July, 2008–2011. We conducted off-road and radiotelemetry surveys on Peabody Wildlife Management Area (PWMA), and additional off-road surveys on Fort Campbell Military Base, Tennessee-Kentucky and on private lands in Livingston County, Kentucky from May through July, 2010–2011.We detected 6,440 individual northern bobwhite on roadside survey routes; .95% of the survey routes had at least 1 northern bobwhite detection. We developed a suite of 17 a priori removal models in Program MARK to estimate roadside survey detection probabilities. The best model included differences in time interval detection, observer, and 3 covariates: distance from the observer, number of individuals aurally detected, and percent forested habitat within a 100-m radius of the point count. Detection probabilities were greatest during the first minute of detection, and then decreased. Detection probabilities (6 SD) decreased as distance from the observer (b 1⁄4 0.0020 6 0.0005, n 1⁄4 6,440) increased, but increased as the number of individuals detected at a point (b 1⁄4 0.15 6 0.04, n 1⁄4 6,440) increased. We used the most parsimonious model and mean covariate values to generate overall parameter estimates, which differed between observers and time intervals. We detected 637 individual northern bobwhite on 90 off-road transects across 4 sites from 2010 to 2011. We developed a suite of 10 a priori occupancy models in Program MARK to estimate off-road survey detection probabilities and site occupancy. Detection probabilities were greater (.26%) during the second point count visit (q 1⁄4 0.69 6 0.03) versus first (q 1⁄4 0.51 6 0.04) and third (q 1⁄4 0.47 6 0.04) visits (n 1⁄4 270). Detection probability increased as relative abundance increased (b 1⁄4 2.90 6 0.22, n 1⁄4 270). Occupancy was held constant and was not affected by any covariates evaluated. Peak northern bobwhite detection probabilities occurred from 1 to 25 June, an important consideration for population models that use breeding season survey data. Distance from road was not a significant grouping variable in any of the models, suggesting that roadside bias may not be an important consideration in designing bobwhite monitoring strategies. We located 295 radio-marked male bobwhites from 2010 to 2011. Marked males called on 115 of 295 points (39.0%). The furthest distance a radio-marked male moved during the survey period was 60 m, and movement distances were generally small (x ̄ 1⁄4 4.2 6 10.3 m, n 1⁄4 295). We compared 8 a priori time-of-detection models in Program MARK to estimate radiotelemetry survey detection probabilities. We grouped surveys based on year and included time-of-day, and day- of-year as additional temporal covariates. Detection probability was inversely related to time of day (b 1⁄4 0.04 6 0.10, n 1⁄4 105), but positively related to day of year (b 1⁄4 0.010 6 0.008, n 1⁄4 105); b estimates overlapped 0 suggested weak relationships. Our results documented the first attempt to explicitly model differences in northern bobwhite detection related to spatial (potential roadside biases, habitat parameters, northern bobwhite distances), temporal (seasonality, annual fluctuations), and behavioral (observer, northern bobwhite relative abundance) variables. We used a combination of 3 methodologies to estimate detection parameters and will adjust indices of relative abundance and density estimates across a broad spatial extent. Our spatially-balanced roadside survey can be effectively used to monitor northern bobwhite populations across broad spatial extents and incorporates the components of detection to improve estimates of northern bobwhite relative abundance