631 research outputs found
Review of \u3ci\u3eTexas Bobwhites: A Guide to Their Foods and Habitat Management.\u3c/i\u3e By Jon A. Larson, Timothy E. Fulbright, Leonard A. Brennan, Fidel Hernandez, and Fred C. Bryant.
Texas Bobwhites: A Guide to Their Foods and Habitat Management is a pictorial guide to the identification of seeds commonly consumed by northern bobwhites (Colinus virginianus)-- and the plants that produce them--in Texas. The authors hope that interest in what constitutes good bobwhite habitat among hunters and nature enthusiasts will be enhanced by this guide to the identification of seeds eaten by quail. Targeting this lay audience leads to certain constraints regarding how the text, particularly, is presented. Regardless, because Texas includes much of the southern terminus of the Great Plains, this book is directly relevant to readers of Great Plains Research interested in bobwhite conservation, identifying seeds eaten by bobwhites and other wildlife, and identifying the plants that produce these seeds
Is Quail Hunting Self-Regulatory? Northern Bobwhite and Scaled Quail Abundance and Quail Hunting in Texas
Wildlife managers often maintain that quail hunting is self-regulatory because they assume hunters spend fewer days hunting, and bag fewer quail per day, when hunting is poor, while hunting more frequently, and bagging more quail per day, when hunting is good. For this reason, managers conclude that minor changes in hunting season length and bag limit are inconsequential. We used August quail abundance (1978-1996) and harvest (1981-1983, 1986---1996) data collected by Texas Parks and Wildlife Department biologists to test the self-regulatory hypothesis for both northern bobwhites (Colinus virginianus) and scaled quail (Callipepla squamata). First, we tested the hypothesis that quail abundance in August was sufficient to account for the total number of quail bagged by hunters during the subsequent hunting season. We then tested the hypotheses that quail abundance could predict: (1) the number of days people hunted quail; (2) the number of quail bagged per hunter per day; and (3) the number of quail hunters during the subsequent hunting season. Quail abundance in August was correlated with the number of northern bobwhite and scaled quail bagged during the following hunting season (r2 = 0.769 and 0.874, P \u3c0.0005, respectively). Texas hunters typically hunted quail about 2.5 to 3 days annually regardless of quail abundance. Quail abundance in August, however, was correlated with the number of quail bagged per hunter per day and the number of quail hunters during the subsequent hunting season (northern bobwhite: r2 = 0.895 and 0.868, P \u3c0.0005, respectively; scaled quail: r2 = 0.833 and 0.740, P \u3c 0.0005, respectively). These results are consistent with the hypothesis that both northern bobwhite and scaled quail abundance can regulate quail hunting effort and success within the framework of the hunting regulations that have been in effect in Texas since the early l 980\u27s
Long-Term Climate Trends and Northern Bobwhite Populations in South Texas
Because climate change and its associated weather changes may influence population trends of birds, we analyzed northern bobwhite (Colinus virginianus; bobwhite hereafter) age ratios and abundance in relation to climate trends during 1908-1997 in south Texas. Weather variables included regional mean temperature maxima for June, July, and August, and precipitation totals for autumn (Sep-Nov), winter (Dec-Feb), spring (Mar-May), and summer (Jun-Aug). Long-term temporal trends for these weather variables were estimated with a linear regression. Yearly weather data were used to predict bobwhite age ratios (juv/ad in autumn and winter) and abundance between 1908 and 1997 using neural network models. We compared these predictions with data available from various bobwhite surveys in south Texas over the period 1940-1999. Means for daily maximum temperature during summer declined at rates between 1.6 and 2.3°C/century. No temporal trends were detected for seasonal precipitation (1908-1997), age ratios (1940-1999), or abundance (1977-1998). Neural models developed independently to predict bobwhite age ratios and bobwhite abundance from weather data produced predictions that were consistent with each other. Years with high age ratios tended to coincide with or precede years of high abundance
Integrating social power and political influence into models of social–ecological systems
Shaping policy for environmental sustainability depends upon decision-makers conceptualizing problems in ways that are either shared or similar enough to communicate about, diagnose, and act. The quality of this shared mental model of a social–ecological system (SES) is paramount to its effectiveness. Fundamentally, the mental model must integrate multiple kinds of knowledge about the system. If the decision-making body's assumptions about, description of, and solution for a problem do not to reflect the many ways stakeholders know a system, then the products of that decision-making process are viewed as illegitimate. Sustainability policy must fit the often subtle social order of the communities expected to implement it. In this essay, we discuss how a systems-based perspective can be a versatile tool for tackling these challenges of knowledge integration and decision-making in the context of a complex SES. Using social theory of Pierre Bourdieu, we construct a conceptual model that illustrates a route for integrating locally known social complexities (power, influence) gleaned from stakeholder interviews (N = 57). Stakeholders and end-user groups may dismiss any model that they perceive fails to satisfactorily account for specific, locally salient social nuances. Our approach leverages the overlapping notion of “capital” in social and ecological theory to demonstrate how reciprocal interactions between human and ecological systems can be adopted into tools for reaching viable solutions to SES problem
A Comparison of Two Quail Abundance Indices and Their Relationship to Quail Harvest in Texas
Surveys are used to monitor status and trends of animal populations. However, different surveys may give conflicting results for the same species and population being surveyed. Therefore, we compared results of the North American Breeding Bird Survey (BBS) and Texas Parks and Wildlife (TPW) roadside counts for scaled quail (Callipepla squamata) and northern bobwhite (Colinus virginianus) in Texas. Surveys were compared on both an ecoregion and statewide basis. The BBS and TPW surveys gave similar trends for bobwhites and scaled quail for 5 of 8, and 3 of 5 ecoregions, respectively. Survey trends differed at the statewide scale for both species. We compared estimated statewide harvest as an independent index of quail population status in Texas with results from both surveys. The TPW roadside survey was more closely related to estimated statewide harvest for northern bobwhites (R2 = 0.86, P \u3c= 0.001) and scaled quail (R2 = 0.75, P = 0.0001) than the BBS survey (R2 = 0.60, P = 0.001; and R2 = 0.35, P = \u3c0.0001, respectively). Survey methods, sampling frameworks, and issues of scale are important variables to consider when interpreting survey results. The BBS provides useful data on quail populations at a multi-state or national scale. However, most state wildlife agencies require surveys that provide information at finer spatial scales
Helminth Community Dynamics in Populations of Blue-Winged Teal (Anas discors) Using Two Distinct Migratory Corridors
The influence of spatially distinct host subpopulations on helminth community structure and pattern was examined in a migratory avian host species. Forty helminth species represented by 24,082 individuals were collected from 184 blue-winged teal (Anas discors; BWT) from 2 primary migratory corridors in Florida (eastern migratory corridor; EMC) and Louisiana and Texas (western migratory corridor; WMC). Mean species richness was greater in BWT from the WMC (x̅±SE = 10.2 ± 0.3 species) than the EMC (8.6 ± 0.2). The helminth community from the WMC had higher abundances of 6 common/intermediate species. Corridor helminth communities were similar in species composition but less similar when incorporating abundances of those species. Overlapping distributions of phylogenetically related host species that share generalist helminth species across ecologically similar habitats seem to mitigate the isolating mechanisms that are necessary for the distinct coevolutionary pathways to develop between adjacent corridors
Landscape-Scale Land-Cover Change and Long-Term Abundance of Scaled Quail and Northern Bobwhite in Texas
Between 1978 and 1998, scaled quail (Callipepla squamata) abundance in the Rolling Plains ecological region declined (r1 = -0.85, P \u3c 0.001), while no trend (P = 0.74) was exhibited in the South Texas Plains. Northern bobwhites (Colinus virginianus) exhibited no trend (P \u3e 0.10) in either ecological region. Changes in land-cover between 1976 and 1998 indicated a loss of Savannah and Shrubland and an increase in Parkland cover types in the Rolling Plains. In the South Texas Plains, Woodland and Brush/Shrubland decreased between 1976 and 1998, whereas Brush/Shrub Parkland and Parkland increased. We examined land-cover change as a possible component in the scaled quail decline in the Rolling Plains. Loss of the Shrubland cover type may explain the decline of scaled quail in the Rolling Plains. Our results further suggest intraspecific spatial usability boundaries. These boundaries differed by species, with scaled quail associated with dense structure near the ground, whereas northern bobwhite were less abundant in areas dominated by scattered shrubs and trees, and large expanses of short, close-canopy cover types. A method is proposed for quickly obtaining data on land-cover changes on time
Interacting Effects of Newcastle Disease Transmission and Illegal Trade on a Wild Population of White-Winged Parakeets in Peru: A Modeling Approach
Impacts of Habitat Fragmentation on Northern Bobwhites in the Gulf Coast Prairie Landscape Conservation Cooperative
The northern bobwhite (Colinus virginianus) has experienced range wide declines over the last several decades, primarily due to loss and fragmentation of habitat. As populations decline, there is a need for understanding factors that impact bobwhite population persistence at local and regional spatial scales. Our goal was to assess changes in land use and their relationship to bobwhite declines at 3 different spatial scales (region, county, and home range) in Texas, Oklahoma, and Louisiana. We used North American Breeding Bird Survey (BBS) data from 1974-2014 to create abundance maps and trends. At the regional scale, we compared bobwhite abundance with road density (2000, 2010), human population (1970-2010), and land use (1974-2012). We then used the BBS data to identify counties with stable and declining bobwhite abundance, and then compared bobwhite abundance to land use at metapopulation (800-9600 ha) and home range scales (15 ha). Bobwhite populations decreased from 45.93 ± 1.01 birds/count in 1970 to 11.55 ± 0.64 birds/count in 2012. as road density and human population increased. Pasture and other land increased, woodland was relatively stable, and cropland decreased in 2012. At the metapopulation level, declining populations had higher road density, more edge and patch area for pasture, and larger patches of cropland compared to stable populations. At the home range scale, declining populations had significantly fewer, and smaller, woody patches, more herbaceous habitat, and less bare ground. This study demonstrates that while on a small scale managers can provide woody cover and reduce cropland effects to support stable populations, the large-scale drivers of bobwhite decline, namely human population growth and the resulting loss of habitat, will be critical to quail management in the future
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