Sustainability at UD

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Health Status of Northern Bobwhite Quail (Colinus virginianus) in Eastern Kansas
(Avian Diseases, 2000) Williams, Christopher K.; Davidson, William R.; Lutz, R. Scott; Applegate, Roger D.
SUMMARY. The health status of wild northern bobwhite quail (Colinus virginianus) from Lyon County, Kansas, was evaluated by conducting comprehensive health assessments on 25 birds. Gross lesions indicative of avian pox, ulcerative enteritis, and quail bronchitis were not present. Serologic tests for antibodies to Salmonella pullorum, Salmonella gallinarum, Pasteurella multocida, Mycoplasma gallisepticum, Mycoplasma synoviae, and avian adenoviruses were all negative. Intestinal coccidia (Eimeria spp.) were found in 36% of the birds. Only three species of helminth parasites were found: Dispharynx nasuta in two birds, Cyrnea colini in one bird, and larval Physaloptera sp. in four birds. Arthropod parasites (ticks, lice, mites, and/ or chiggers) were present on 96% of the birds examined. Compared with wild bobwhite populations in the southeastern United States, the diversity, prevalence, and intensities of microbial and parasitic agents were low. RESUMEN. Nota de Investigacion-Estado de salud de la codorniz blanca del Norte en el oriente de Kansas. Se realiz6 un estudio detallado del estado de salud de la codorniz silvestre blanca del norte (Colinus virginianus) en el condado de Lyon, Kansas en 25 aves. Las lesiones a la necropsia indicaron que la viruela aviar, la enteritis ulcerativa y la bronquitis de la codorniz no estaban presentes. Las pruebas serologicas para anticuerpos contra Salmonella pullorum, Salmonella gallinarum, Pasteurella multocida, Mycoplasma gallisepticum, Mycoplasma synoviae y adenovirus aviares fueron negativas. Se observ6 coccidia intestinal (Eimeria spp.) en 36% de las aves. Se encontraron tres especies de helmintos uinicamente, Dispharynx nasuta en dos aves, Cyrnea colini en un ave y un estado larvario de Physaloptera sp. en cuatro aves. Los parasitos artropodos (garrapatas, piojos, acaros y niguas) estuvieron presentes en el 96% de las aves examinadas. La diversidad, la prevalencia y la intensidad de agentes parasiticos y microbianos fue baja, comparada con las poblaciones silvestres de codornices blancas en el sureste de los Estados Unidos.
A comparison of raptor densities and habitat use in Kansas cropland and rangeland ecosystems
(Journal of Raptor Research, 2000-09) Williams, Christopher K.; Applegate, Roger D.; Lutz, R. Scott; Rusch, Donald H.
We counted raptors on line transects along roads to assess densities, species diversity, and habitat selection of winter raptors between cropland and rangeland habitats in eastern Kansas. We conducted counts every 2 wk between September-March 1994-98. Species diversity indices did not differ between the two habitats (P -- 0.15). We calculated density estimates and cover type selection for Red- tailed Hawks (Buteojamaicensis), Northern Harriers (Circus cyaneus), and American Kestrels (Falco sparv- erius). Red-tailed Hawks and Northern Harrier densities were higher in cropland, while kestrel densities did not differ between the two habitats. All three species across both habitats had a general preference for idleland habitat. We believe three factors could explain the higher raptor densities in cropland: increased prey abundance, increased visibility of prey associated with harvested agriculture fields, and/ or a higher relative amount of preferred hunting habitat.
A Quantitative Summary of Attitudes toward Wolves and Their Reintroduction (1972-2000)
(Wildlife Society Bulletin, 2002) Williams, Christopher K.; Ericsson, Göran; Heberlein, Thomas A.
This paper reports an analysis of support for wolves (Canis spp.) reported in 38 quantitative surveys conducted between 1972 and 2000. Of 109 records reported in these surveys, a majority (51 %) showed positive attitudes toward wolves and 60% supported wolf restoration. Attitudes toward wolves had a negative correlation with age, rural residence, and ranching and farming occupations, and positive correlation with education and income. Thirty-five percent of ranchers and farmers surveyed had positive attitudes toward wolves. Among surveys of the general population samples, 61 % expressed positive attitudes. Surveys of environmental and wildlife groups showed an average of 69% support. Surveys in the lower 48 states showed higher proportions of positive attitudes than surveys in Scandinavia and Western Europe, where a majority did not support wolves. Among all surveys, 25% of respondents had neutral attitudes toward wolves. Positive attitudes toward wolves did not appear to be increasing over time. Because attitudes toward wolves are often not strong among the general public, they have the potential to change rapidly if linked to other, stronger attitudes and beliefs. We expect that progress in education and urbanization will lead to increasingly positive attitudes over time. Negative attitudes associated with age are probably a cohort effect, and we should not expect the aging populations in the United States and Europe to lead to more negative wolf attitudes. Paradoxically, successful wolf reintroductions are likely to reduce general positive sentiment, since the presence of wolves gives people a more balanced experience with the animals. Traditionally, people with the most positive attitudes toward wolves have been those with the least experience.
A portable aviary for field observations of behavior
(Journal of Field Ornithology, 2002-01-01) Van Why, Kyle R.; Williams, Christopher K.; Applegate, Roger D.; Flock, Brian E.
We describe a lightweight, portable, and inexpensive field aviary that was designed for observing Northern Bobwhite (Colinus virginianus) vigilance and feeding behavior. The general construction details of this aviary are easily modified to accommodate a variety of bird species and research objectives. SINOPSIS. Aviario portatil para hacer observaciones en el campo sobre la conducta de aves Describimos un aviario porta´til, liviano y de bajo costo disen˜ado para hacer estudios sobre la conducta alimentaria de Colinus virginianus. Los detalles en generales de construccio´n de este aviario se puede modificar fa´cilmente para acomodar una gran variedad de aves y diferentes objetivos de investigacio´n.
The effect of flooding on northern bobwhite
(Western North American Naturalist, 2002-04) Applegate, Roger D.; Williams, Christopher K.; Lutz, R. Scott
Effects of flooding on mammals (Yeager and Anderson 1944) and reptiles (Stickel 1948) have been documented, and Northern Bob- whites ( Colinus virginianus) have been known to drown (Schorger 1946, Mullan and Apple- gate 1969). However, on landscape and population scales, the implications of mortality from extensive flooding are undocumented for birds. We document mortality of bob whites, possibly by drowning, because of flooding in east central Kansas.
Population dynamics across geographical ranges: time-series analysis of three small game species
(Ecology, 2003-10-01) Williams, Christopher K.; Ives, Anthony R.; Applegate, Roger D.
Little is known about how density-independent and density-dependent processes affecting population dynamics vary geographically across species' ranges. To address this problem for three vertebrate species (Northern Bobwhite [Colinus virginianus], Ring-necked Pheasants [Phasianus colchicus], and eastern cottontails [Sylvilagus floridanus]), we examined spatially subdivided, long-term (1966–2001), seasonal (January, April, July, and October), time-series data from the Kansas Rural Mail Carrier Survey, USA. All three species have range boundaries in Kansas, with population abundances declining toward the periphery of their ranges. We quantified the strengths of density-dependent and density-independent processes affecting the dynamics of 10 populations of each species ranging from low (peripheral) to high (central) mean abundance using first-order autoregressive models that incorporate measurement error. For all three species, peripheral populations with lower mean abundance tended to have greater population variability. This pattern could potentially be explained by peripheral regions experiencing either weaker density dependence or greater environmentally driven density-independent fluctuations in per capita population growth rates. In general, density dependence did not vary among geographic regions, although there was a trend for smaller, peripheral populations to exhibit stronger density dependence. Density-independent variability in per capita population growth rates was higher in peripheral populations. Furthermore, density-independent fluctuations in per capita population growth rates were weakly correlated with temperature and precipitation and were highest for the period October through January, identifying fall as the period of greatest environmentally driven variability in population dynamics. Per capita population growth rates fluctuated in moderate synchrony among regions, especially for more abundant, nonperipheral populations in close geographical proximity. The strong density-dependent and stronger density-independent processes in smaller, peripheral populations suggest that the greater variability in peripheral populations' densities is caused by greater population sensitivity to environmental fluctuations. This may make peripheral populations more likely to go extinct and leads to the prediction that, if these species decline to the point of becoming endangered, this decline will be accompanied by a contraction in their geographical ranges.
Assuring the future of prairie grouse: dogmas, demagogues, and getting outside the box
(Wildlife Society Bulletin, 2004-03) Applegate, Roger D.; Williams, Christopher K.; Manes, Robert R.
We discuss the necessity of a paradigm shift among managers toward dealing with the recovery and management of prairie grouse (Tympanuchus spp). To assure the future of these species, we will need to test dogmatic assumptions about grouse and their management and challenge the demagogues who insist on perpetuating untested “principles.” Tolerance for descriptive and qualitative studies is needed. Additionally, managers will need to remove themselves from the box and embrace landowners, theoretical biologists, economists, human-dimensions researchers, marketing and advertising specialists, and many other professionals outside the normal sphere of wildlife management. There is crucial need for a willingness to devise, test, and apply innovative ideas that are not normally considered in the management of grouse species, especially applying management to large areas within ecosystems. A comprehensive plan is needed to guide rangewide prairie grouse management. Planned management systems are needed to provide operational guidance in implementing species plans.
The northern bobwhite decline: scaling our management for the twenty-first century
(Wildlife Society Bulletin, 2004-09) Williams, Christopher K.; Guthery, Fred S.; Applegate, Roger D.; Peterson, Markus J.
Northern bobwhites (Colinus virginianus) are one of the most broadly researched and intensively managed species in North America. However, we argue that a disadvantage of this status is that traditional management principles currently are incompatible with the spatial scale necessary to address the nationwide decline in bobwhite abundance. We maintain that halting or reversing this decline will entail 2 principal changes in the scale of management. Primarily we suggest that habitat oversight must switch from historical fine-scale management (promotion of edge habitat, weedy fencelines, disked strips, living hedges, and food plots) to regional management of usable space. Secondly, within these regional management areas, we should apply harvest management that employs risk-sensitive strategies that conservatively avoid undermining the primary goal. This entails narrowing the scale of harvest management from statewide to regional levels. If these ideological changes cannot be made and historical policies remain in force, we risk failing to stabilize, let alone increase, bobwhite populations.
Phylogenetic Measures of Biodiversity
(The American Naturalist, 2007-01-17) Helmus, Matthew R.; Bland, Thomas J.; Williams, Christopher K.; Ives, Anthony R.
We developed a theoretical framework based on phylogenetic comparative methods to integrate phylogeny into three measures of biodiversity: species variability, richness, and evenness. These metrics can be used in conjunction with permutation procedures to test for phylogenetic community structure. As an illustration, we analyzed data on the composition of 58 lake fish communities in Wisconsin. The fish communities showed phylogenetic underdispersion, with communities more likely to contain closely related species. Using information about differences in environmental characteristics among lakes, we demonstrated that phylogenetic underdispersion in fish communities was associated with environmental factors. For example, lakes with low pH were more likely to contain species in the same clade of acid‐tolerant species. Our metrics differ from existing metrics used to calculate phylogenetic community structure, such as net relatedness index and Faith’s phylogenetic diversity. Our metrics have the advantage of providing an integrated and easy‐to‐understand package of phylogenetic measures of species variability, richness, and evenness with well‐defined statistical properties. Furthermore, they allow the easy evaluation of contributions of individual species to different aspects of the phylogenetic organization of communities. Therefore, these metrics should aid with the incorporation of phylogenetic information into strategies for understanding biodiversity and its conservation.
The northern bobwhite of the Mid-Atlantic: a landowners guide to their ecology and management
(Cooperative Extension of the University of Delaware, 2010) Colavecchio, Ashley; Williams, Christopher K.
Northern bobwhite (Colinus virginianus) have long been aesthetically and economically prized gamebirds in North America. Historically, bobwhite flourished in traditional farmlands where farming and grazing practices created an early successional patchwork of agriculture, grasslands, old fields, and woody edges; under persistent social and biological pressures like predation and hunting, suitable habitat was bobwhite’s safeguard against obliteration. Since WWII, however, farming practices have changed, and the bobwhite’s habitat has changed with them. For those who grew up before the 1960’s the “bob-white” song echoing over the farmlands of eastern America provides a nostalgic memory of a landscape that is quickly disappearing. Current trends toward cleaner farming, larger plot sizes and conversion to non-native grasses or crowded pine stands, and conversion to suburbia have reduced the amount of habitat available to bobwhite nesting and escape cover. For states such as New Jersey, which is the most developed state in the Union, these habitat conversions are especially drastic. Consequently, for at least half a century, bobwhite numbers have followed a downward trend throughout the bird’s range.
Do Invasive Fire Ants Affect Habitat Selection within a Small Mammal Community?
(International Journal of Ecology, 2010-12-27) Holtcamp, Wendee N.; Williams, Christopher K.; Grant, William E.
Animals must balance foraging with the need to avoid predators and risky habitats that decrease their fitness, and at the same time they must cope with competitors vying for habitat and resources. We examined how habitat selection and population density of four native small mammals were altered by the presence of red imported fire ants (Solenopsis invicta). When population size was low, hispid cotton rats (Sigmodon hispidus) and pigmy mice (Baiomys taylori) as well as white-footed mice (Peromyscus leucopus) used the “safe”, low fire ant habitat, as predicted by theories of density-dependent habitat selection. However, as fire ant population sizes expanded, cotton rats appeared to displace pigmy mice into the fire ant-dense grassland drainage while white-footed mice (Peromyscus leucopus) displaced all the other small mammals from low fire ant forest/brushland habitat.
Mid-Atlantic Regional Issues in Bobwhite Conservation
(National Bobwhite Technical Committee Technical Publication, 2011) Long, Bob; Williams, Christopher K.
The Mid-Atlantic region encompasses 5 states (Delaware, Maryland, New Jersey, Pennsylvania, West Virginia) and portions of 3 BCRs. The NBCI has identified 4.6 million, high-priority acres for bobwhite and bird conservation in these states totaling 14 million acres. Although these states lie on the northern fringe of current bobwhite range bobwhites were historically widespread and abundant in the region. Some of the steepest population declines have been recorded in the Mid-Atlantic region of the U.S. For example since 1996 bobwhite populations in the Mid-Atlantic have declined 6%/year; within that, there are worrisome declines such as a 13%/year decline in New Jersey since 1980. The regional declines are especially troublesome when in 1966 the national Breeding Bird Survey recorded the highest densities of bobwhite in the country right in Delaware (Figure 22).
Observed Herring Gull Kleptoparasitism of American Black Ducks
(Journal of Fish and Wildlife Management, 2011-12-01) Jones, Orrin E.; Castelli, Paul M.; Williams, Christopher K.
Herring gulls Larus argentatus were observed to kleptoparasitize American black ducks Anas rubripes feeding on fiddler crabs Uca pugnax in coastal New Jersey. Although widespread in Laridae, kleptoparasitism has never been described between these two species. Over two winters of intensive 24-hour behavioral observations, this interaction was observed on two occasions during similar tidal conditions. Although this appears to be a rare interaction with limited energetic consequences, we note that quantifying these uncommon interspecific interactions is a benefit of thorough behavior observations, which may refine estimates of daily energy expenditure.
A Mid-Atlantic and a National Population Model of Northern Bobwhite Demographic Sensitivity
(National Quail Symposium Proceedings, 2012) Williams, Christopher K.; Sandercock, Brett K.; Lohr, Michael; Castelli, Paul M.
Numerous field studies have estimated fecundity and survival rates for northern bobwhites (Colinus virginianus), but a synthetic population model based on life-stage simulation analysis (LSA) was only recently developed to examine demographic sensitivity of the finite rate of population change. We compare local demographic parameters of bobwhite versus a national compilation to identify limiting demographic factors for improved regional habitat planning and management. The national compilation provided a useful overview but combined parameters across populations at different latitudes and under different management regimes. We parameterized our LSA model to examine the sensitivity of the finite rate of growth (k) to simulated variation in 9 demographic parameters primarily estimated from field studies for one population in regional decline in New Jersey. Our model results predicted population declines in New Jersey (k 1⁄4 0.55) comparable to the national estimate (k 1⁄4 0.54), but notable differences occurred in sensitivity of demographic variables. The national model predicted winter survival of adults made the greatest contribution to variance of k (r2 1⁄4 0.42) followed by summer survival of adults (r2 1⁄4 0.13), and survival of chicks (r2 1⁄4 0.11). Our regional model for New Jersey also predicted winter and summer survival of adults would make the greatest contribution to variance of k (r2 1⁄4 0.33 and r2 1⁄4 0.13). The New Jersey model, in contrast to the national model, showed that annual variation in components of fecundity had a large effect on Var(k): including clutch size (r2 1⁄4 0.18 vs. national r2 1⁄4 0.01), nest success (r2 1⁄4 0.20 vs. national r2 1⁄4 0.06), and the number of young produced per nest that survived 30 days (r2 1⁄4 0.53 vs. national r2 1⁄4 0.16). Slopes of linear regression between simulated variation in each demographic variable against k were similar between the national and regional models. The slope for number of young produced per nest that survived 30 days with one exception was lower in the New Jersey data indicating more young are required to realize a stationary population. Our simulation results suggest management practices that improve winter survival or the number of young surviving 30 days will have the greatest potential to increase bobwhite population growth rate in New Jersey. Future linkage of models of demographic performance to experimental habitat manipulations will aid regional scientific planning to improve necessary habitat management.
Do Resident and Non-Resident Northern Bobwhite Hunters Self-Regulate Harvest Based on Population Size?
(National Quail Symposium Proceedings, 2012) Williams, Christopher K.; Applegate, Roger D.
A variety of factors influence the relative strength of additive and compensatory mortality of harvest on northern bobwhite (Colinus virginianus) including covey dynamics, habitat fragmentation, and timing of harvest. State wildlife agencies have long believed regulations could be liberal because hunters will self-regulate effort when populations decrease. A confounding observation is that with lower population abundances, hunter skill and harvest rate increases because the more novice hunters do not participate. This raises the question whether non-resident small game hunters could have a larger impact at lower population levels if they have (1) more money to dedicate to out of state licenses and travel/lodging, and (2) time to dedicate to the hunting experience? We examined long-term bobwhite population and harvest data from Kansas (1966–1999) to learn if self-regulation differed between resident and non-resident small game hunters. The number of resident and non-resident small game hunters was related to their respective harvest of northern bobwhites. Decreasing October population index was associated with a decline in the number of resident bobwhite hunter days and harvest. Conversely, increasing numbers of non-resident hunters participated in the hunting season with higher hunter efficiency and a larger harvest at lower October population index levels. Total relative harvest decreased overwinter (Oct–Jan) survival. The Kansas resident bobwhite harvest is probably self-regulatory but non-resident harvest is not. Future harvest regulations should consider the impact of non-resident harvest.
Determining Effective Riparian Buffer Width for Nonnative Plant Exclusion and Habitat Enhancement
(International Journal of Ecology, 2012-03-18) Ferris, Gavin; D'Amico, Vincent; Williams, Christopher K.
Nonnative plants threaten native biodiversity in landscapes where habitats are fragmented. Unfortunately, in developed areas, much of the remaining forested habitat occurs in fragmented riparian corridors. Because forested corridors of sufficient width may allow forest interior specializing native species to retain competitive advantage over edge specialist and generalist nonnative plants, identifying appropriate corridor widths to minimize nonnative plants and maximize ecosystem integrity is of habitat management concern. We measured the occurrences of 4 species of nonnative plants across the widths of 31 forested riparian corridors of varying widths in the White Clay Creek watershed of Pennsylvania and Delaware. Using repeated measures ANOVA, Japanese honeysuckle (Lonicera japonica) and multiflora rose (Rosa multiflora) prevalence did not significantly decline across buffer widths. However, garlic mustard (Alliaria petiolata) and oriental bittersweet (Celastrus orbiculatus) declined strongly within the first 15–25 m. Managing for riparian corridor widths a minimum of 15–25 m has the potential to enhance habitat quality but no corridor width (≤55 m) will exclude all invasive plants.
Effects of broadcasting calls during surveys to estimate density and occupancy of northern bobwhite
(Wildlife Society Bulletin, 2012-03-23) Duren, Kenneth R.; Buler, Jeffrey J.; Jones, William L.; Williams, Christopher K.
We assessed the effects of using a broadcast caller during surveys and increasing survey duration to estimate northern bobwhite (Colinus virginianus) density and occupancy. From 15 May 2009 to 15 August 2009, we conducted repeat-visit breeding bobwhite surveys at 180 sites in Delaware, USA. Increasing survey duration from 3 min to 7 min, or using a broadcast caller, improved detection probability for a single visit by 52% and 42%, respectively. However, density estimates when using a broadcast caller were biased high—≥3 times greater compared to passive-listening surveys. Density estimates for 3-min and 7-min passive surveys were not different. Additionally, bobwhite occupancy was similar among all 3 survey treatments. Use of a broadcast caller to survey for bobwhites appears to violate the assumption of distance sampling that an individual is detected prior to movement. Use of a broadcast caller is inappropriate for determining density estimates through distance sampling, but may be appropriate for determining site occupancy. © 2011 The Wildlife Society.
Evaluation of a clutch-containment method during hatch in geese: Using resident Canada geese as an example
(Wildlife Society Bulletin, 2012-04-10) Guerena, Katherine B.; Castelli, Paul M.; Nichols, Theodore C.; Williams, Christopher K.
Disruption associated with nest visits during the hatch period of waterfowl can cause partial abandonment of hatchlings, potentially causing bias in the survival of marked birds. We evaluated the use of a mesh clutch-containment bag to capture and mark entire broods of 151 resident Canada goose (Branta canadensis) nests, prior to hatch, while minimizing observer-caused disruption during brooding. The study was conducted in New Jersey, USA, from April to June 2010. No differences were found in hatch success or the number of hatchlings marked between contained clutches and the control group. Although this technique was not beneficial in studying gosling survival in temperate nesting populations, it may be effective in sub-Arctic nesting conditions where nest visits are conducted using a more invasive approach such as a helicopter. © 2012 The Wildlife Society.
Estimating habitat carrying capacity for migrating and wintering waterfowl: considerations, pitfalls and improvements
(Wildfowl, 2014) Williams, Christopher K.; Dugger, Bruce D.; Brasher, Michael G.; Coluccy, John M.; Cramer, Dane M.; Eadie, John M.; Gray, Matthew J.; Hagy, Heath M.; Livolsi, Mark; McWilliams, Scott R.; Petrie, Mark; Soulliere, Gregory J.; Tirpak, John M.; Webb, Elizabeth B.
Population-based habitat conservation planning for migrating and wintering waterfowl in North America is carried out by habitat Joint Venture (JV) initiatives and is based on the premise that food can limit demography (i.e. food limitation hypothesis). Consequently, planners use bioenergetic models to estimate food (energy) availability and population-level energy demands at appropriate spatial and temporal scales, and translate these values into regional habitat objectives. While simple in principle, there are both empirical and theoretical challenges associated with calculating energy supply and demand including: 1) estimating food availability, 2) estimating the energy content of specific foods, 3) extrapolating site-specific estimates of food availability to landscapes for focal species, 4) applicability of estimates from a single species to other species, 5) estimating resting metabolic rate, 6) estimating cost of daily behaviours, and 7) estimating costs of thermoregulation or tissue synthesis. Most models being used are daily ration models (DRMs) whose set of simplifying assumptions are well established and whose use is widely accepted and feasible given the empirical data available to populate such models. However, DRMs do not link habitat objectives to metrics of ultimate ecological importance such as individual body condition or survival, and largely only consider food-producing habitats. Agent-based models (ABMs) provide a possible alternative for creating more biologically realistic models under some conditions; however, ABMs require different types of empirical inputs, many of which have yet to be estimated for key North American waterfowl. Decisions about how JVs can best proceed with habitat conservation would benefit from the use of sensitivity analyses that could identify the empirical and theoretical uncertainties that have the greatest influence on efforts to estimate habitat carrying capacity. Development of ABMs at restricted, yet biologically relevant spatial scales, followed by comparisons of their outputs to those generated from more simplistic, deterministic models can provide a means of assessing degrees of dissimilarity in how alternative models describe desired landscape conditions for migrating and wintering waterfowl.
Spatially-explicit land use effects on nesting of Atlantic Flyway resident Canada geese in New Jersey
(Wildlife Biology, 2014-04-01) Guerena, Katherine B.; Castelli, Paul M.; Nichols, Theodore C.; Williams, Christopher K.
Atlantic Flyway resident population (AFRP) Canada geese Branta canadensis in New Jersey, USA, have grown dramatically during the last thirty years and are considered as overabundant in many areas. Development of corporate parks and urban areas with manicured lawns and artificial ponds offer ideal nesting habitat for AFRP geese, with limited pressure from hunting or natural predators. As a result, spatial heterogeneity in reproduction must be taken into account in managing the population. We identified the site and landscape spatial scale extents at which land use features influenced nest site selection and nest success. Nest searches were conducted throughout the State during 2009—2010, and 309 nests were monitored through hatch to determine their fates. We ran a spatial correlation analysis of land use composition to identify spatial scale extents at which geese most considerably respond to their environment for nest site selection and nest success. All significant spatial scale extents were at or below 2.25 km for the five classified land use types. We emphasize that habitat-goose associations in densely urban areas were strongest at extents < 1 km, while rural and natural areas were strongest at extents > 1 km. Geese responded to human-dominated land uses at a smaller spatial scale extent than land uses with low human density. The strength of all nest-land use univariate relationships was low; however, our primary objective was to identify the scales extent at which geese associate with land use, rather than the intensity. We encourage managers to consider these scale-dependent associations in identifying important habitat variables in multivariate models; and if population control of AFRP Canada geese is of primary interest, then focusing on local habitat management will most likely have the largest influence in managing this population.

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