Northern Bobwhite habitat selection during the nonbreeding season in a riparian corridor in Colorado

BackgroundEfficient movement and energy expenditure are vital for animal survival. Human disturbance can alter animal movement due to changes in resource availability and threats. Some animals can exploit anthropogenic disturbances for more efficient movement, while others face restricted or inefficient movement due to fragmentation of high-resource habitats, and risks associated with disturbed habitats. Mining, a major anthropogenic disturbance, removes natural habitats, introduces new landscape features, and alters resource distribution in the landscape. This study investigates the effect of mining on the movement of an endangered mesopredator, the northern quoll (Dasyurus hallucatus). Using GPS collars and accelerometers, we investigate their habitat selection and energy expenditure in an active mining landscape, to determine the effects of this disturbance on northern quolls.MethodsWe fit northern quolls with GPS collars and accelerometers during breeding and non-breeding season at an active mine site in the Pilbara region of Western Australia. We investigated broad-scale movement by calculating the movement ranges of quolls using utilisation distributions at the 95% isopleth, and compared habitat types and environmental characteristics within observed movement ranges to the available landscape. We investigated fine-scale movement by quolls with integrated step selection functions, assessing the relative selection strength for each habitat covariate. Finally, we used piecewise structural equation modelling to analyse the influence of each habitat covariate on northern quoll energy expenditure.ResultsAt the broad scale, northern quolls predominantly used rugged, rocky habitats, and used mining habitats in proportion to their availability. However, at the fine scale, habitat use varied between breeding and non-breeding seasons. During the breeding season, quolls notably avoided mining habitats, whereas in the non-breeding season, they frequented mining habitats equally to rocky and riparian habitats, albeit at a higher energetic cost.ConclusionMining impacts northern quolls by fragmenting favoured rocky habitats, increasing energy expenditure, and potentially impacting breeding dispersal. While mining habitats might offer limited resource opportunities in the non-breeding season, conservation efforts during active mining, including the creation of movement corridors and progressive habitat restoration would likely be useful. However, prioritising the preservation of natural rocky and riparian habitats in mining landscapes is vital for northern quoll conservation.

Contemporary landscape change driven by socio-economic forces and advances in agricultural technology do not favor northern bobwhites (Colinus virginianus) in the Midwestern United States. The challenge of bobwhite conservation is to provide sufficient quantities of habitat with optimal configurations in proportions that satisfy needs throughout the year on private-owned working lands. We radio-tracked 58 coveys and 98 individual birds throughout the year in 2009-10 and 2010-11 on privately owned farmland in southwestern Ohio. We investigated temporal changes in usable space from use-availability data. Estimated proportions of usable space based on analyses of habitat selection across four study sites were 0.06-0.12 during the non-breeding season compared to 0.10-10.30 during the breeding season. We also modeled probabilities that radio-marked coveys or individual birds used points within individual cover types as a function of distance to other cover types. Locations of radio-marked coveys and individual birds within focal cover types were closer to other cover types compared to random points during breeding (mean = 44 m) and non-breeding (mean = 58 m) seasons. Probability of use within focal cover types declined with distance to other cover types, typically falling below 50% when distances exceeded 9-242 m. Locations of radio-marked coveys were concentrated near edges within used cover types, while locations of individual birds were more dispersed during the breeding season. Estimated proportions of usable space based on distances between locations of radio-marked bobwhites and nearest cover types were higher (0.30-0.53) than estimates based on habitat selection ratios, and were similar between non-breeding and breeding seasons. Potentially usable sites were not fully occupied in either season, but there was no relationship between crude covey densities and proportions of usable space estimated from habitat selection analyses during the breeding and non-breeding seasons across study sites and years (r2 < 0.166, P > 0.316). With distance to cover type estimates of usable space (years combined), two study sites with the highest proportions of usable space (0.43-0.53) also had the largest crude covey densities (0.0065-0.153 coveys/ha) compared to the other two sites with lower proportions of usable space (0.30-0.32) and smaller covey densities (0.004 – 0.006 coveys/ha). Habitat enhancement should focus on providing protective cover near food for coveys during the non-breeding season and protective cover near nesting and brood-rearing habitat during the breeding season. Conserving Midwestern bobwhite populations requires innovative practices that can be implemented on private lands as economic incentives change for farm operators. Improving protective cover along habitat edges can increase usable space by improving cover type juxtaposition (e.g. food near cover) while minimizing impact on farming practices.

We measured the home ranges and habitat use of 11 Red-shouldered Hawks (Buteo lineatus) during the breeding season and 9 during the nonbreeding season in suburban Ohio, using standard telemetry techniques. Mean home ranges, calculated using the adaptive kernel method (95% isopleth), were 90 ha ;pm 11 SE during the breeding season, 189 ha ;pm 33 SE during the nonbreeding season, and 165 ha ;pm 24 SE for the annual home range. Males and females did not differ significantly in home range size. We examined habitat use by hawks by classifying the habitat where birds were observed perching. Habitat used by hawks differed significantly from that available within home ranges for all birds tested. Most Red-shouldered Hawks used riparian zones and pond edges more than expected, based on availability of such habitats within their home ranges; residential areas and lawns were used less than expected or in proportion to their availability.

Riparian systems support disproportionately high biodiversity and are critical for avian conservation in the western United States, yet much historic riparian habitat has been lost or degraded. Restoration of riparian vegetation and associated ecological processes is a high priority, and birds can serve as indicators of restoration success. Here, we analyze data from 17 y of constant-effort mist netting at an urban riparian restoration site to examine changes in capture rates from 2001 to 2017. Capture rates of 4 of 17 species commonly using the site during autumn, and 6 of 14 species using the site during winter, increased over time, and more so in the restored area compared to the mature riparian reference area. This suggests that these birds increased use of the restored habitat area as riparian tree and shrub plantings matured. Birds that responded positively to restoration included several species that breed in and are considered indicators of coniferous forest habitats (Purple Finch, Oregon Junco, Hermit Thrush, and Fox Sparrow) that often inhabit riparian areas during the non-breeding season. Species that breed in riparian habitat did not show as consistent or as strong of a non-breeding season response to restoration. Riparian birds associated with open, wet herbaceous vegetation (Common Yellowthroat and Lincoln's Sparrow) declined in the restored area in autumn while maintaining stable capture rates in the reference area. Three species of finch (Spinus spp.) used the restored habitat, and the site as a whole, in far fewer numbers during the autumn dispersal and migration period in the years following restoration, likely owing to invasive teasel removal efforts. Taken together, these results suggest that restoration actions can result in trade-offs that benefit some birds while reducing suitable habitat for others. Birds complete important activities in the autumn and winter, including dispersal, migration stopover, and molt, so restoration work that supports bird populations during the non-breeding season, even at relatively small urban sites, can make important contributions to their conservation. However, managers should consider the goals of restoration actions in the context of species- or guild-specific responses to restoration-associated changes in vegetation structure.

Northern Bobwhite (Colinus virginianus) Space Use Minimally Affected by Oil and Gas Development

The elegant trogon (Trogon elegans) is a rare Neotropical migrant bird that occurs in southeasteri Arizona, where very little is known about this species in regards to potential threats to it, or habitat resources used by it. Consequently, we studied habitat selection by the elegant trogon at 4 spatial scales (mountain range canyon, home range, nest site) in southeastern Arizona to determine what resources constituted high-quality habitat (i.e., areas related to successful breeding and persistence of elegant trogons). At the broadest scales, elegant trogons were found in 4 mountain ranges. in canyons where there were sycamore trees (Platanus wrightu) in riparian areas. and mesquite (Prosopis spp.) in upland areas. Within home ranges, radiotagged elegant trogons used both riparian and upland areas, and successfully breeding elegant trogons used areas with dense understory vegetation. Nest sites were primarily located in sycamore trees and oaks (Quercus spp.) in riparian areas. Across all scales, elegant trogons were associated with variables describing sycamores. oaks, and pines (Pinus spp.). which indicated the importance of these trees as resources. We suggest management of elegant trogons in Arizona will require consideration of whole watersheds because elegant trogons use both riparian and upland zones, and management should include maintenance of high water tables in canyons to promote growth and recruitment of sycamore trees.

The Middle Spotted Woodpecker (Leiopicus medius) is a strict forest bird whose habitat preferences during the breeding season are well known. However, a lack of information about its habitat selection during the non-breeding season may hamper recommendations for the management and conservation of the species. Here we study habitat selection of this woodpecker at its southwestern boundary range (Izki Natural Park, northern Spain) during the non-breeding season (October–December) by means of a use–availability approach. We also examined seasonal differences in habitat use between the breeding season (April–May) and the non-breeding season. Results of ANOVA and backward-stepwise logistic regression revealed a clear selection of high forest cover, large Pyrenean oaks (Quercus pyrenaica), and presence of dead trees during the non-breeding season. Despite very similar habitat use in both seasons, minor but interesting differences between seasons were observed, with a potential expansion during the non-breeding season into less mature forests (lower forest cover and fewer large trees) with a greater abundance of dead trees. These differences may reflect seasonal changes in the spatial requirements of the species and a decrease in food abundance during autumn–winter. On the basis of these findings, we propose management measures to improve the conservation status of the species in the Iberian Peninsula.

ABSTRACTIf differences in ecological requirements result in juvenile birds using different habitats from breeding birds, then habitat management to protect those birds must protect both breeding and post‐breeding habitats. We examined habitat selection by juvenile black‐capped vireos (Vireo atricapilla) following their independence from parental care, in 2010–2013 on Fort Hood Military Reservation in central Texas, USA. The black‐capped vireo is a federally endangered species that nests almost exclusively in shrub vegetation, but previous anecdotal observations indicate that juveniles may prefer riparian vegetation. We used mist‐net capture rates and radio‐telemetry to determine relative abundance of juvenile vireos across habitats, to quantify movement patterns and habitat selection, and to investigate how vegetation density and arthropod abundance influenced habitat selection. We captured juveniles at similar rates in shrub and riparian vegetation. Radio telemetry data indicated that juveniles selected riparian vegetation over most other available vegetation types, and tended to stay in riparian vegetation upon arrival. Juveniles selected areas characterized by more canopy cover, denser foliage, and more arthropods. Riparian vegetation provides this combination of features more than other vegetation types, indicating that cover and food are the basis for habitat selection by juveniles. Our results indicate that habitat conservation strategies for black‐capped vireos should include protection of riparian vegetation near breeding areas, and more generally, that avian conservation strategies that focus only on breeding areas may potentially overlook other key habitats. © 2014 The Wildlife Society.

Northern bobwhite (Colinus virginianus; hereafter, bobwhite) in the Mid-Atlantic United States have been experiencing precipitous population declines due to a combination of habitat deterioration, urban and suburban sprawl, change in forest management regimes, and farming practices. In recent years, restocking of bobwhite through translocation efforts has gained interest to rebuild local populations. However, empirical studies are warranted to understand the limitations of translocation as it relates to its potential use for long-term population recovery and persistence in this region. Further, few studies nation-wide have evaluated resource use and survival during the non-breeding season on translocated sites. As such, we translocated 360 bobwhites from source populations from southern latitudes during March–April 2015–2017 into 2 different landscape types similar to the source population vegetative communities (agricultural cropland dominated in Maryland, USA versus pine forest dominated in New Jersey, USA) and tested the effects of habitat fragmentation on survival and habitat use during the subsequent non-breeding season. We found habitat fragmentation negatively affecting survival and resource use among translocated bobwhite on fragmented cropland-dominated sites as compared to larger unfragmented forested sites. Survival was lower on cropland sites compared to forested sites such that bobwhite in cropland-dominated landscapes were >125 times less likely to survive the winter than those on forested sites. In our examination of resource use, bobwhite in structurally complex forested sites used cut pine, early-successional woody, early-successional herbaceous, and thinned pine more than what was available on the landscape. On the cropland sites bobwhite used food plots, early-successional woody, and mixed woods more than what was available on the landscape and only food plots at the home range scale. While larger unfragmented forested bobwhite habitat ultimately provided a more successful translocation landscape, birds still had large home ranges and relatively low survival. Therefore, proper pine management may be necessary to optimize habitat availability during the non-breeding season. Our findings provide rare information on demographic resiliency and resource use for translocated bobwhite during the non-breeding season. Further, this research provides valuable information to improve future translocation efforts in the Mid-Atlantic.

We recorded telemetry locations from 1,129 radiotagged turkeys (Meleagris gallopavo intermedia) on 4 study areas in the Texas Panhandle and southwestern Kansas, USA, from 2000 to 2004. Analyses of telemetry locations indicated both sexes selected riparian vegetative zones. Females did not select grazed or nongrazed pastures for daily movements. However, females did select nongrazed pastures for nest sites on 2 study areas and males selected for grazed pastures at one study area during the breeding season. We compared nest sites (n = 351) to random sites using logistic regression, which indicated height of visual obstruction, percent canopy cover, and percent bare ground provided the highest predictive power (P ≤ 0.003) for characteristics describing nest‐site selection. Nest‐site vegetative characteristics between vegetative zones differed primarily in composition: upland zone nest sites had more (P ≤ 0.001) shrubs and riparian zone nest sites had more (P ≤ 0.001) grass. There were no differences in measured nest site vegetative characteristics between pasture types, but there were differences between available nesting cover in grazed and nongrazed pastures. Random plots in grazed pastures had less grass cover (P ≤ 0.001) and more bare ground (P = 0.002). Because of cattle impacts on average grass height and availability, grazing would likely have the highest impact on nesting in riparian zones due to turkey use of grass as nesting cover. An appropriate grazing plan to promote Rio Grande turkey nesting habitat would include grazing upland zones in the spring, when it likely has little impact on nesting‐site selection, and grazing riparian zones following breeding season completion. Grazing at light to moderate intensities with periods of rest did not affect male turkey pasture use and may have continued to maintain open areas used by male turkeys for displaying purposes.

Avifauna of riparian communities were studied in Iowa during late spring and early summer. Birds were censused on 28 study plots representing a habitat gradient from hayfields to closed-canopy woodlands. An index of nesting niche breadth was determined for 18 open-nesting bird species on the basis of vegetation life form(s) used for nesting, and for 10 cavity-nesting species on the basis of type(s) of nest-cavity support. Cavity-nesters preferred soft snags as nest sites. Floodplain woodlands supported higher densities of breeding birds than upland woodland or herbaceous habitats. Bird species richness increased (P < 0.01) with the width of wooded riparian habitats. Wooded habitats supported a maximum of 32 species; herbaceous habitats, 8. Observation frequencies of 41 bird species in 6 general habitat types were used to calculate indices of tolerance to habitat alteration. Microhabitat characteristics selected by each species were determined by comparing bird observation frequencies with 36 vegetation variables, using stepwise multiple regression. The potential effects of 6 alterations to wooded riparian habitats on the 41 species are predicted. J. WILDL. MANAGE. 44(1):1-15 Riparian habitats are critical to wildlife, especially in regions with intensive agriculture where streamside habitat is being depleted rapidly. Nongame birds constitute a major component of riparian wildlife communities, but most research concerning nongame bird management has been local in nature or concerned with endangered species (Robbins and Erskine 1975). Recently, contributors to several symposia have emphasized the need for research on management of all nongame birds (Smith 1975; DeGraaf 1978a,b). Such research is essential to assess the impacts of habitat alterations on the associated wildlife (Lennartz and Bjugstad 1975). Our study is an attempt to satisfy part of that need. Our objectives were to quantify factors critical in nest-site and habitat selection by breeding birds of riparian communities over a range of habitat types and to use the results to evaluate effects of habitat perturbations on avian communities. The results are applicable to both riparian and upland habitats of the Central Plains and, with caution, could be used in other areas as well. We are grateful to the landowners of Guthrie County, Iowa, for their cooperation in all phases of the field work. T. Rosburg and R. Deitchler assisted in collecting field data. D. F. Cox, L. Wolins, M. Hand, and B. J. Meador provided help with the statistics and computer analysis. J. J. Dinsmore, R. B. Dahlgren, and R. Q. Landers reviewed an earlier draft of the manuscript. The manuscript also benefited from the suggestions of 2 anonymous referees.

The Eurasian Otter (Lutra lutra) in the Alpine Arc: Resource selection and habitat suitability models

Examining seasonal patterns of space use to gauge how an accipiter responds to urbanization

Improved control need fuels NMS growth: Able Telecommunications Inc., USA (1988) $2 250

Behavioral Responses at Distribution Extremes: How Artificial Surface Water Can Affect Quail Movement Patterns