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Role Of Dispersal Timing And Frequency In Annual Grass-Invaded Great Basin Ecosystems: How Modifying Seeding Strategies Increases Restoration Success, Merilynn C. Schantz, Roger L. Sheley, Jeremy J. James, Eric P. Hamerlynck Mar 2016

Role Of Dispersal Timing And Frequency In Annual Grass-Invaded Great Basin Ecosystems: How Modifying Seeding Strategies Increases Restoration Success, Merilynn C. Schantz, Roger L. Sheley, Jeremy J. James, Eric P. Hamerlynck

Western North American Naturalist

Seed dispersal dynamics strongly affect plant community assembly in restored annual grass–infested ecosystems. Modifying perennial grass seeding rates and frequency may increase perennial grass establishment, yet these impacts have not yet been quantified. To assess these effects, we established a field experiment consisting of 288 plots (1 m2) in an eastern Oregon annual grass–dominated shrubsteppe ecosystem. In this study, the amount, timing, and frequency of perennial grass seeding events, soil moisture availability, and annual grass seed bank density were manipulated. We found that more frequent perennial grass seeding events combined with high perennial grass seeding rates produced ...


Population Differentiation In Early Life History Traits Of Cleome Lutea Var. Lutea In The Intermountain West, Lisa Hintz, Magdalena M. Eshleman, Alicia Foxx, Troy E. Wood, Andrea Kramer Mar 2016

Population Differentiation In Early Life History Traits Of Cleome Lutea Var. Lutea In The Intermountain West, Lisa Hintz, Magdalena M. Eshleman, Alicia Foxx, Troy E. Wood, Andrea Kramer

Western North American Naturalist

Large-scale restoration is occurring in many areas of the western United States and the use of genetically appropriate native plant seed is expected to increase the success of restoration efforts. Thus, determining intraspecific variation among populations and its driving forces are the first steps in successful seed sourcing. Here, we examine intraspecific variation of characters expressed in early life history stages of Cleome lutea var. lutea, an annual forb native to the western United States that has attracted increasing attention as a restoration species because it provisions diverse pollinators. We conducted a common garden experiment comprised of 9 populations sourced ...


Use Of Barn Owl (Tyto Alba) Pellets As A Potential Method To Study A Rare Rodent Population In Northeastern New Mexico, Christopher B. Goguen Mar 2016

Use Of Barn Owl (Tyto Alba) Pellets As A Potential Method To Study A Rare Rodent Population In Northeastern New Mexico, Christopher B. Goguen

Western North American Naturalist

In June 2008, I discovered a single jumping mouse (Zapus) cranium in a Barn Owl (Tyto alba) pellet from below an active nest along Cerrososo Creek, Colfax County, northeastern New Mexico. Although the cranium could not be identified to species, this specimen could potentially represent a previously unknown population of the endangered New Mexico meadow jumping mouse (Z. hudsonius luteus). In 2009 and 2010, I collected pellets at 8 Barn Owl nesting or roosting sites along streams in my study area with the following objectives: (1) determine whether Barn Owl pellets could be used to gain information about the abundance ...


Front Matter, Vol. 76 No. 1 Mar 2016

Front Matter, Vol. 76 No. 1

Western North American Naturalist

No abstract provided.


Identification Of Columbian Sharp-Tailed Grouse Lek Sites In South Central Wyoming, Kurt T. Smith, Jeffrey L. Beck, Tony W. Mong, Frank C. Blomquist Mar 2016

Identification Of Columbian Sharp-Tailed Grouse Lek Sites In South Central Wyoming, Kurt T. Smith, Jeffrey L. Beck, Tony W. Mong, Frank C. Blomquist

Western North American Naturalist

The Columbian Sharp-tailed Grouse (Tympanuchus phasianellus columbianus; hereafter CSTG) occupies approximately 10% of its historic range and is a species of conservation concern in 7 U.S. states and British Columbia. Because little is known about the status of CSTG in Wyoming, we sought to model the relative probability of lek site occurrence within the known distribution of CSTG in the state to identify areas that contained previously undocumented lek sites. The proximity of nesting and brood-rearing habitats to leks advocates their use as a focus of conservation for prairie grouse, including CSTG. We modeled a resource selection function (RSF ...


Environmental Influences On Wintering Duck Adundance At Great Salt Lake, Utah, Anthony J. Roberts, Michael R. Conover, Josh L. Vest Mar 2016

Environmental Influences On Wintering Duck Adundance At Great Salt Lake, Utah, Anthony J. Roberts, Michael R. Conover, Josh L. Vest

Western North American Naturalist

North American waterfowl winter throughout a large geographic area, and the choice of wintering site has a direct impact on survival and fitness. Climatic and food variables are the most commonly cited factors influencing abundance and distribution of wintering migratory birds, including waterfowl. We conducted stratified aerial surveys at a northern latitude wintering site, Great Salt Lake (GSL), Utah, to describe the importance of this wintering area and to examine the influence of weather and food on the abundance of total ducks, Northern Shovelers (Anas clypeata), and goldeneye species (Bucephala spp.). Surveys indicated that up to 270,000 ducks use ...


Acoustic Detection Reveals Fine-Scale Distributions Of Myotis Lucifugus, Myotis Septentrionalis, And Perimyotis Subflavus In Eastern Nebraska, Jeremy A. White, Cliff A. Lemen, Patricia W. Freeman Mar 2016

Acoustic Detection Reveals Fine-Scale Distributions Of Myotis Lucifugus, Myotis Septentrionalis, And Perimyotis Subflavus In Eastern Nebraska, Jeremy A. White, Cliff A. Lemen, Patricia W. Freeman

Western North American Naturalist

Before white-nose syndrome arrives in Nebraska, it is important to document the preexposure distributions of cave bats in the state. We examined the distributions ofMyotis lucifugus (little brown myotis), Myotis septentrionalis (northern long-eared myotis), and Perimyotis subflavus (tri-colored bat) in eastern Nebraska by setting acoustic detectors for a single night at 105 sites in wooded habitats during summers of 2012 and 2014. We compared 2 methods of determining presence at each site. Results of our analyses are fine-scale distributional maps for these bats and some range extensions from published records. Results for M. septentrionalis and P. subflavus are largely ...


Biogeochemistry And Nutrient Limitation Of Microbial Biofilms In Devils Hole, Nevada, Hilary L. Madinger, Kevin P. Wilson, Jeffery A. Goldstein, Melody J. Bernot Mar 2016

Biogeochemistry And Nutrient Limitation Of Microbial Biofilms In Devils Hole, Nevada, Hilary L. Madinger, Kevin P. Wilson, Jeffery A. Goldstein, Melody J. Bernot

Western North American Naturalist

Little is known about the role of microbial biofilms in nutrient cycling and ecosystem processes within desert springs. However, biofilms produce microscale physicochemical variation important to ecosystem function. We used microelectrodes to measure microscale physicochemical (temperature, pH, O2, and H2S) heterogeneity in biofilms at Devils Hole, Nevada. Additionally, we measured water column and pore water nutrient concentrations in 2 autotrophic (Spirogyra, cyanobacteria) and 1 heterotrophic (Beggiatoa) biofilm types. Spirogyra and cyanobacteria followed similar physicochemical trends; however, Spirogyra had more pronounced diurnal and seasonal variation. Oxygen concentrations within the biofilms varied with sample month, light availability, and biofilm ...


Ecosystem Engineering Of Harvester Ants: Effects On Vegetation In A Sagebrush-Steppe Ecosystem, Elyce N. Gosselin, Joseph D. Holbrook, Katey Huggler, Emily Brown, Kerri T. Vierling, Robert S. Arkle, David S. Pilliod Mar 2016

Ecosystem Engineering Of Harvester Ants: Effects On Vegetation In A Sagebrush-Steppe Ecosystem, Elyce N. Gosselin, Joseph D. Holbrook, Katey Huggler, Emily Brown, Kerri T. Vierling, Robert S. Arkle, David S. Pilliod

Western North American Naturalist

Harvester ants are influential in many ecosystems because they distribute and consume seeds, remove vegetation, and redistribute soil particles and nutrients. Understanding the interaction between harvester ants and plant communities is important for management and restoration efforts, particularly in systems altered by fire and invasive species such as the sagebrush-steppe. Our objective was to evaluate how vegetation cover changed as a function of distance from Owyhee harvester ant (Pogonomyrmex salinus) nests within a sagebrush-steppe ecosystem. We sampled 105 harvester ant nests within southern Idaho, USA, that occurred in different habitats: annual grassland, perennial grassland, and native shrubland. The influence of ...


Translocation Of The Endangered San Joaquin Kit Fox, Vulpes Macrotis Mutica: A Retrospective Assessment, Jerry H. Scrivner, Thomas P. O'Farrell, Kristie Hammer, Brian L. Cypher Mar 2016

Translocation Of The Endangered San Joaquin Kit Fox, Vulpes Macrotis Mutica: A Retrospective Assessment, Jerry H. Scrivner, Thomas P. O'Farrell, Kristie Hammer, Brian L. Cypher

Western North American Naturalist

In 1988, a study of federally endangered San Joaquin kit foxes (Vulpes macrotis mutica) was initiated to develop techniques for translocating kit foxes onto Naval Petroleum Reserve No. 1 (NPR-1) in California. Our objective is to review the translocation program and provide recommendations for future efforts. There were no problems trapping, translocating, and maintaining foxes in captivity. We released 12 foxes onto NPR-1 in 1989 and 28 foxes in 1990. Of the 12 foxes released in 1989, 10 died within 1 year. Of 28 foxes released in 1990, 1 was still alive, 24 were dead, and the fate of 3 ...


Seasonal Distribution And Routes Of Pronghorn In The Northern Great Basin, Gail H. Collins Mar 2016

Seasonal Distribution And Routes Of Pronghorn In The Northern Great Basin, Gail H. Collins

Western North American Naturalist

Pronghorn (Antilocapra americana) exhibit complex spatial and temporal variation in seasonal movements and range use across their distribution. However, knowledge of seasonal movements, routes, and distribution of pronghorn within the sagebrush-steppe of the northern Great Basin is lacking. From October 2011 to October 2013, I monitored movements of adult female pronghorn across an area of over 1.5 million hectares along the northwestern Nevada and southeastern Oregon border using GPS/VHF-equipped collars. I used 68,834 GPS locations from 32 female pronghorn to determine migration timing, seasonal distributions, individual fidelity to winter and summer ranges, and population-level routes used during ...


Conspecific Pollen Loads On Insects Visiting Female Flowers On Parasitic Phoradendron Californicum (Viscaceae), William D. Wiesenborn Mar 2016

Conspecific Pollen Loads On Insects Visiting Female Flowers On Parasitic Phoradendron Californicum (Viscaceae), William D. Wiesenborn

Western North American Naturalist

Desert mistletoe, Phoradendron californicum (Viscaceae), is a dioecious parasitic plant that grows on woody legumes in the Mojave and Sonoran Deserts, produces minute flowers during winter, and is dispersed by birds defecating fruits. Pollination of desert mistletoe has not been examined despite the species’ reliance on insects for transporting pollen from male to female plants. I investigated the pollination of P. californicum parasitizing Acacia greggii (Fabaceae) shrubs at 3 sites at different elevations in the Mojave Desert of southern Nevada during February 2015. I examined pollen from male flowers, aspirated insects landing on female flowers, and counted pollen grains in ...


Temporary Communal Brooding In Northern Bobwhite And Scaled Quail Broods, Jeremy P. Orange, Craig A. Davis, R. Dwayne Elmore, Samuel D. Fuhlendorf Mar 2016

Temporary Communal Brooding In Northern Bobwhite And Scaled Quail Broods, Jeremy P. Orange, Craig A. Davis, R. Dwayne Elmore, Samuel D. Fuhlendorf

Western North American Naturalist

Communal brooding, which can occur as a result of brood amalgamation or communal parental care, is a common alternative brooding strategy observed in many precocial bird species. Although the occurrence of long-term communal brooding has been documented in numerous waterfowl species, and to a lesser extent in gallinaceous species, the occurrence and mechanisms facilitating temporary or short-term communal broods is less understood. During the 2013 and 2014 breeding seasons, we anecdotally observed temporary communal brooding in 3 Northern Bobwhite (Colinus virginianus) broods and one Scaled Quail (Callipepla squamata) brood. We present 3 mechanisms that may explain the occurrences of temporary ...


Reviewers For 2015 Mar 2016

Reviewers For 2015

Western North American Naturalist

No abstract provided.


End Matter, Vol. 76 No. 1 Mar 2016

End Matter, Vol. 76 No. 1

Western North American Naturalist

No abstract provided.


A New Springsnail (Hydrobiidae: Pyrgulopsis) From The Lower Colorado River Basin, Northwestern Arizona, Robert Hershler, Hsiu-Ping Liu, Lawrence E. Stevens Mar 2016

A New Springsnail (Hydrobiidae: Pyrgulopsis) From The Lower Colorado River Basin, Northwestern Arizona, Robert Hershler, Hsiu-Ping Liu, Lawrence E. Stevens

Western North American Naturalist

We describe a new springsnail species, Pyrgulopsis hualapaiensis, from the Lower Colorado River basin (northwestern Arizona) that has an ovate- to narrow-conic shell and narrow penis ornamented with a small gland on the distal edge of the lobe. This new species differs from closely similar congeners from the Lower Colorado River basin in several details of female reproductive anatomy and in its mtCOI haplotype (3.0%–5.0% mean sequence divergence). Bayesian, maximum parsimony, and distance-based phylogenetic analyses of COI data congruently resolved P. hualapaiensis as sister to a divergent lineage of Pyrgulopsis thompsoni in the middle Gila River watershed ...


Badger Behavior At Anthropogenic Water Sources In The Chihuahuan Desert, Robert L. Harrison Mar 2016

Badger Behavior At Anthropogenic Water Sources In The Chihuahuan Desert, Robert L. Harrison

Western North American Naturalist

Anthropogenic water sources such as tanks and ponds for livestock and troughs for wildlife (guzzlers) have become ubiquitous features of arid landscapes. Many species of wildlife are attracted to guzzlers, but behavior at guzzlers and effects of guzzlers upon wildlife are often poorly understood. I recorded rates of drinking and visitation by American badgers (Taxidea taxus) at guzzlers in the northern Chihuahuan Desert by use of automatic cameras over a 2-year period. Badgers visited guzzlers throughout the year, and visited primarily at night. Badgers averaged 1.87 visits per site-week and drank during only 58% of visits. The rate of ...


A Herpetological Inventory Of Naval Air Station Fallon, Churchill County, Nevada, Jonathan P. Rose, Oliver J. Miano, Gary R. Cottle, Robert E. Lovich, Robert L. Palmer, Brian D. Todd Dec 2015

A Herpetological Inventory Of Naval Air Station Fallon, Churchill County, Nevada, Jonathan P. Rose, Oliver J. Miano, Gary R. Cottle, Robert E. Lovich, Robert L. Palmer, Brian D. Todd

Western North American Naturalist

Much of the western United States is managed by state and federal agencies for multiple uses, including recreation, grazing, extraction, and defense. Biological inventories are integral to proper management and conservation of biodiversity on these lands. We surveyed for amphibians and reptiles occurring on Naval Air Station Fallon (NAS Fallon), Nevada, USA, using a variety of methods. We documented the presence of a majority of the amphibian and reptile species native to this region of the Great Basin. We found 5 species on NAS Fallon that are listed as Species of Conservation Priority by the Nevada Department of Wildlife: the ...


Using Detection Dogs And Rspf Models To Assess Habitat Suitability For Bears In Greater Yellowstone, Jon P. Beckmann, Lisette P. Waits, Aimee Hurt, Alice Whitelaw, Scott Bergen Dec 2015

Using Detection Dogs And Rspf Models To Assess Habitat Suitability For Bears In Greater Yellowstone, Jon P. Beckmann, Lisette P. Waits, Aimee Hurt, Alice Whitelaw, Scott Bergen

Western North American Naturalist

In the northern U.S. Rockies, including the Greater Yellowstone Ecosystem (GYE), connectivity is a concern because large carnivores have difficulties dispersing successfully between protected areas. One area of high conservation value because of its importance for connecting the GYE to wilderness areas of central Idaho is the Centennial Mountains and surrounding valleys (2500 km2) along the Idaho–Montana border just west of Yellowstone National Park. The current expansion of grizzly bears (Ursus arctos) and other large carnivore populations outside protected areas of Yellowstone National Park and Grand Teton National Park has placed a greater emphasis on potential linkage zones ...


Phenetic Analyses And Revised Classification Of The Ptelea Trifoliata Complex (Rutaceae), Erin Skornia, Muxi Yang, Wendy L. Applequist Dec 2015

Phenetic Analyses And Revised Classification Of The Ptelea Trifoliata Complex (Rutaceae), Erin Skornia, Muxi Yang, Wendy L. Applequist

Western North American Naturalist

The current classification of Ptelea divides the widespread and highly variable Ptelea trifoliata L. into 5 subspecies and 11 varieties, while additionally terming many specimens “intermediate.” Although there are visually observable differences among regional variants, principal component analyses of quantitative characters failed to separate subspecies or to even incompletely separate most varieties within subspecies. Some recognized subgroups are also not well distinguished by discontinuous qualitative characters. Where multiple varieties appear to be part of a single continuum of variation or are extremely similar, it is suggested that a reduction in the number of infraspecific taxa would improve the utility of ...


Facing A Changing World: Thermal Physiology Of American Pikas (Ochotona Princeps), Hans W. Otto, James A. Wilson, Erik A. Beever Dec 2015

Facing A Changing World: Thermal Physiology Of American Pikas (Ochotona Princeps), Hans W. Otto, James A. Wilson, Erik A. Beever

Western North American Naturalist

American pikas (Ochotona princeps) are of concern with respect to warming montane temperatures; however, little information exists regarding their physiological ability to adapt to warming temperatures. Previous studies have shown that pikas have high metabolism and low thermal conductance, which allow survival during cold winters. It has been hypothesized that these characteristics may be detrimental, given the recent warming trends observed in montane ecosystems. We examined resting metabolic rate, surface activity, and den and ambient temperatures (Ta) of pikas in late summer (August 2011 and 2012) at 2 locations in the Rocky Mountains. Resting metabolic rate was calculated to be ...


Production And Nutrient Content Of Two Shrub Species Related To Fire In Central Idaho, James M. Peek Dec 2015

Production And Nutrient Content Of Two Shrub Species Related To Fire In Central Idaho, James M. Peek

Western North American Naturalist

Nutrient content and weight of current year’s growth of Cercocarpus ledifolius Nuttall and Physocarpus malvaceus (Greene) Kuntze in central Idaho were obtained during early July in the years 1987–2007. The purpose of this work was to determine whether there was significant variation between years and whether mean monthly temperatures and total monthly precipitation could predict the variation. A wildfire in August 2000 causedP. malvaceus to vigorously resprout. Significant differences between years occurred for all nutrients for both species. October temperatures best predicted weight of current year’s growth in C. ledifolius, whereas prediction equations for nutrients involved ...


Life History, Burrowing Behavior, And Distribution Of Neohermes Filicornis (Megaloptera: Corydalidae), A Long-Lived Aquatic Insect In Intermittent Streams, Matthew R. Cover, Jeong Ho Seo, Vincent H. Resh Dec 2015

Life History, Burrowing Behavior, And Distribution Of Neohermes Filicornis (Megaloptera: Corydalidae), A Long-Lived Aquatic Insect In Intermittent Streams, Matthew R. Cover, Jeong Ho Seo, Vincent H. Resh

Western North American Naturalist

Several species of fishflies (Megaloptera: Corydalidae: Chauliodinae) have been reported from intermittent streams in western North America, but the life histories and distributions of these species are poorly understood. We studied the life history ofNeohermes filicornis (Banks 1903) for 2 years in Donner Creek (Contra Costa County, California), a small intermittent stream that flows for 5–7 months per year. Neohermes filicornis had a 3–4-year life span and larval growth was asynchronous. Analysis of gut contents showed that larvae were generalist predators of aquatic insect larvae including Diptera, Ephemeroptera, and Plecoptera. Final instars dug pupal chambers in the ...


Black-Tailed And White-Tailed Jackrabbits In The American West: History, Ecology, Ecological Significance, And Survey Methods, Matthew T. Simes, Kathleen M. Longshore, Kenneth E. Nussear, Greg L. Beatty, David E. Brown, Todd C. Esque Dec 2015

Black-Tailed And White-Tailed Jackrabbits In The American West: History, Ecology, Ecological Significance, And Survey Methods, Matthew T. Simes, Kathleen M. Longshore, Kenneth E. Nussear, Greg L. Beatty, David E. Brown, Todd C. Esque

Western North American Naturalist

Across the western United States, Leporidae are the most important prey item in the diet of Golden Eagles (Aquila chrysaetos). Leporids inhabiting the western United States include black-tailed (Lepus californicus) and white-tailed jackrabbits (Lepus townsendii) and various species of cottontail rabbit (Sylvilagus spp.). Jackrabbits (Lepus spp.) are particularly important components of the ecological and economic landscape of western North America because their abundance influences the reproductive success and population trends of predators such as coyotes (Canis latrans), bobcats (Lynx rufus), and a number of raptor species. Here, we review literature pertaining to black-tailed and white-tailed jackrabbits comprising over 170 published ...


First Record Of Jaguar (Panthera Onca) From The State Of Hidalgo, México, Melany Aguilar-López, Josefina Ramos-Frías, Alberto E. Rojas-Martínez, Cristian Cornejo-Latorre Dec 2015

First Record Of Jaguar (Panthera Onca) From The State Of Hidalgo, México, Melany Aguilar-López, Josefina Ramos-Frías, Alberto E. Rojas-Martínez, Cristian Cornejo-Latorre

Western North American Naturalist

We documented the first record of jaguar (Panthera onca) in the state of Hidalgo, México. With this record, the gap in the distribution of jaguar between San Luis Potosí and northwestern Puebla is reduced. In July 2013, we found 2 tracks on a trail in a pine-oak forest, and in October, we photographed a jaguar in an oak forest. Both sites are located within the Parque Nacional Los Mármoles in Sierra Gorda of Hidalgo. These records represent the first evidence of the presence of jaguar in Hidalgo, which is among the few states where all 6 species of felids that ...


Front Matter, Vol. 75 No. 4 Dec 2015

Front Matter, Vol. 75 No. 4

Western North American Naturalist

No abstract provided.


End Matter, Vol. 75 No. 4 Dec 2015

End Matter, Vol. 75 No. 4

Western North American Naturalist

No abstract provided.


A Comparison Of Sign Searches, Live-Trapping, And Camera-Trapping For Detection Of American Badgers (Taxidea Taxus) In The Chihuahuan Desert, Robert L. Harrison Dec 2015

A Comparison Of Sign Searches, Live-Trapping, And Camera-Trapping For Detection Of American Badgers (Taxidea Taxus) In The Chihuahuan Desert, Robert L. Harrison

Western North American Naturalist

In communities where they occur, American badgers (Taxidea taxus) play important ecological, economic, and conservation roles. Central to understanding of badger ecology and management are estimates of badger population status. However, few studies have compared methods of detecting badgers for population surveys. I compared searches for burrows and diggings, live-trapping, and the use of automatic cameras at scent lures, bait stations, and anthropogenic permanent and temporary wildlife water sources in the Chihuahuan Desert of southern New Mexico. Searches for confirmed badger burrows and diggings yielded 0.14–0.88 detections per kilometer of transect. Badgers were trapped in 1.6 ...


Maternity Roost Selection By Fringed Myotis In Colorado, Mark A. Hayes, Rick A. Adams Dec 2015

Maternity Roost Selection By Fringed Myotis In Colorado, Mark A. Hayes, Rick A. Adams

Western North American Naturalist

Fringed myotis (Myotis thysanodes) is a bat species of conservation concern in western North America that may be impacted by increased recreational activity near roost sites, changes in water resource availability caused by increased urban and agricultural water use, and anthropogenic climate change. Our purpose was to describe and model maternity roost use by fringed myotis in Colorado. We compared differences between roosts occupied by maternal fringed myotis and randomly selected potential roosting locations that were not known to be occupied by this species during the maternity period. We evaluated the strength of evidence for competing hypotheses on 2 scales ...


Comparative Nest-Site Habitat Of Painted Redstarts And Red-Faced Warblers In The Madrean Sky Islands Of Southeastern Arizona, Joseph L. Ganey, William M. Block, Jamie S. Sanderlin, Jose M. Iniguez Oct 2015

Comparative Nest-Site Habitat Of Painted Redstarts And Red-Faced Warblers In The Madrean Sky Islands Of Southeastern Arizona, Joseph L. Ganey, William M. Block, Jamie S. Sanderlin, Jose M. Iniguez

Western North American Naturalist

Conservation of avian species requires understanding their nesting habitat requirements. We compared 3 aspects of habitat at nest sites (topographic characteristics of nest sites, nest placement within nest sites, and canopy stratification within nest sites) of 2 related species of ground-nesting warblers (Red-faced Warblers,Cardellina rubrifrons, n = 17 nests; Painted Redstarts, Myioborus pictus, n = 22 nests) in the Sky Island mountain ranges of southeastern Arizona. These species nested in several forest and woodland cover types that occurred along an elevational gradient. Red-faced Warblers nested primarily toward the upper end of that gradient, in pine (Pinus spp.)–oak (Quercus spp.) and ...