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Full-Text Articles in Life Sciences
Genetic And Environmental Drivers Of Migratory Behavior In Western Burrowing Owls And Implications For Conservation And Management, Kelly Barr, Christen M. Bossu, Rachel A. Bay, Eric C. Anderson, Jim Belthoff, Lynne A. Trulio, Debra Chromczak, Colleen L. Wisinski, Thomas B. Smith, Kristen C. Ruegg
Genetic And Environmental Drivers Of Migratory Behavior In Western Burrowing Owls And Implications For Conservation And Management, Kelly Barr, Christen M. Bossu, Rachel A. Bay, Eric C. Anderson, Jim Belthoff, Lynne A. Trulio, Debra Chromczak, Colleen L. Wisinski, Thomas B. Smith, Kristen C. Ruegg
Biology Faculty Publications and Presentations
Migration is driven by a combination of environmental and genetic factors, but many questions remain about those drivers. Potential interactions between genetic and environmental variants associated with different migratory phenotypes are rarely the focus of study. We pair low coverage whole genome resequencing with a de novo genome assembly to examine population structure, inbreeding, and the environmental factors associated with genetic differentiation between migratory and resident breeding phenotypes in a species of conservation concern, the western burrowing owl (Athene cunicularia hypugaea). Our analyses reveal a dichotomy in gene flow depending on whether the population is resident or migratory, …
Illegal Shooting Is Now A Leading Cause Of Death Of Birds Along Power Lines In The Western Usa, Eve C. Thomason, Natalie J. S. Turley, James R. Belthoff, Tara J. Conkling, Todd E. Katzner
Illegal Shooting Is Now A Leading Cause Of Death Of Birds Along Power Lines In The Western Usa, Eve C. Thomason, Natalie J. S. Turley, James R. Belthoff, Tara J. Conkling, Todd E. Katzner
Biology Faculty Publications and Presentations
Human actions, both legal and illegal, affect wildlife in many ways. Inaccurate diagnosis of cause of death undermines law enforcement, management, threat assessment, and mitigation. We found 410 dead birds collected along 196 km of power lines in four western USA states during 2019–2022. We necropsied these carcasses to test conventional wisdom suggesting that electrocution is the leading cause of death of birds at electrical infrastructure. Of 175 birds with a known cause of death, 66% died from gunshot. Both raptors and corvids were more likely to die from gunshot than from other causes, along both transmission and distribution lines. …
American Kestrel Migration: Insights And Challenges From Tracking Individuals Across The Annual Cycle, Anjolene R. Hunt, Jesse L. Watson, Jason M. Winiarski, Ron R. Porter, Julie A. Heath
American Kestrel Migration: Insights And Challenges From Tracking Individuals Across The Annual Cycle, Anjolene R. Hunt, Jesse L. Watson, Jason M. Winiarski, Ron R. Porter, Julie A. Heath
Biology Faculty Publications and Presentations
Natural variation in migratory strategies across the range of the American Kestrel (Falco sparverius) creates a unique opportunity for comparative research of annual cycles. However, it can be logistically and technically challenging to track such a small but highly mobile species. We tagged American Kestrels with light-level geolocators or satellite transmitters with the aim of estimating migration timing and connectivity, and we monitored a subset of satellite-tagged individuals during the breeding season to assess transmitter function and wear. We recovered geolocators from six of 49 (12%) tagged individuals. One geolocator-tagged individual migrated approximately 1235 km from its Idaho …
Phenology Effects On Productivity And Hatching-Asynchrony Of American Kestrels (Falco Sparverius) Across A Continent, Kathleen R. Callery, Sarah E. Schulwitz, Anjolene R. Hunt, Jason M. Winiarski, Christopher J. W. Mcclure, Richard A. Fischer, Julie A. Heath
Phenology Effects On Productivity And Hatching-Asynchrony Of American Kestrels (Falco Sparverius) Across A Continent, Kathleen R. Callery, Sarah E. Schulwitz, Anjolene R. Hunt, Jason M. Winiarski, Christopher J. W. Mcclure, Richard A. Fischer, Julie A. Heath
Biology Faculty Publications and Presentations
Optimal reproductive performance occurs when birds time reproduction to coincide with peak food availability. Deviation from optimal timing, or mismatch, can affect productivity, though birds may mediate some mismatch effects by altering their incubation behavior. We studied the consequences of nesting timing (i.e., clutch initiation relative to an index of spring start) on productivity across the breeding range of American kestrels (Falco sparverius) in the United States and southern Canada, and associations between nesting timing, incubation behavior, and hatching asynchrony. We used observations from long-term nest box monitoring, remote trail cameras, and community-scientist-based programs to obtain data on …
Clock-Linked Genes Underlie Seasonal Migratory Timing In A Diurnal Raptor, Christen M. Bossu, Julie A. Heath, Gregory S. Kaltenecker, Barbara Helm, Kristen C. Ruegg
Clock-Linked Genes Underlie Seasonal Migratory Timing In A Diurnal Raptor, Christen M. Bossu, Julie A. Heath, Gregory S. Kaltenecker, Barbara Helm, Kristen C. Ruegg
Biology Faculty Publications and Presentations
Seasonal migration is a dynamic natural phenomenon that allows organisms to exploit favourable habitats across the annual cycle. While the morphological, physiological and behavioural changes associated with migratory behaviour are well characterized, the genetic basis of migration and its link to endogenous biological time-keeping pathways are poorly understood. Historically, genome-wide research has focused on genes of large effect, whereas many genes of small effect may work together to regulate complex traits like migratory behaviour. Here, we explicitly relax stringent outlier detection thresholds and, as a result, discover how multiple biological time-keeping genes are important to migratory timing in an iconic …
Seasonal Trends In Adult Apparent Survival And Reproductive Trade-Offs Reveal Potential Constraints To Earlier Nesting In A Migratory Bird, Kathleen R. Callery, John A. Smallwood, Anjolene R. Hunt, Emilie R. Snyder, Julie A. Heath
Seasonal Trends In Adult Apparent Survival And Reproductive Trade-Offs Reveal Potential Constraints To Earlier Nesting In A Migratory Bird, Kathleen R. Callery, John A. Smallwood, Anjolene R. Hunt, Emilie R. Snyder, Julie A. Heath
Biology Faculty Publications and Presentations
Birds aim to optimize resources for feeding young and self-maintenance by timing reproduction to coincide with peak food availability. When reproduction is mistimed, birds could incur costs that affect their survival. We studied whether nesting phenology correlated with the apparent survival of American kestrels (Falco sparverius) from two distinct populations and examined trends in clutch-initiation dates. We estimated apparent survival using multi-state mark-recapture models with nesting timing, nesting success, sex, age, and weather covariates. Nesting timing predicted the apparent survival of successful adults; however, the effect differed between populations. Early nesting kestrels had higher apparent survival than later …
Drivers Of Flight Performance Of California Condors (Gymnogyps Californianus), Sophie R. Bonner, Sharon A. Poessel, Joseph C. Brandt, Molly T. Astell, James R. Belthoff, Todd E. Katzner
Drivers Of Flight Performance Of California Condors (Gymnogyps Californianus), Sophie R. Bonner, Sharon A. Poessel, Joseph C. Brandt, Molly T. Astell, James R. Belthoff, Todd E. Katzner
Biology Faculty Publications and Presentations
Flight behavior of soaring birds depends on a complex array of physiological, social, demographic, and environmental factors. California Condors (Gymnogyps californianus) rely on thermal and orographic updrafts to subsidize extended bouts of soaring flight, and their soaring flight performance is expected to vary in response to environmental variation and, potentially, with experience. We collected 6298 flight tracks described by high-frequency GPS telemetry data from five birds ranging in age from 1 to 19 yr old and followed over 32 d in summer 2016. Using these data, we tested the hypothesis that climb rate, an indicator of flight performance, …
Commentary: The Past, Present, And Future Of The Global Raptor Impact Network, James R. Belthoff, Julie A. Heath
Commentary: The Past, Present, And Future Of The Global Raptor Impact Network, James R. Belthoff, Julie A. Heath
Biology Faculty Publications and Presentations
Most raptor populations are declining and nearly a fifth are threatened with extinction; thus there is a need to increase collaboration to ensure efficient and effective research, management, and conservation. Here, we introduce the Global Raptor Impact Network (GRIN; www.globalraptors.org), a tool to enhance collaboration and conservation impact of the raptor research community. We provide an overview of the history and current state of GRIN, including plans for expansion. Predecessors to GRIN include The African Raptor DataBank, which was launched in 2012 to ascertain the conservation status of raptors across Africa; and the Global Raptor Information Network, which was launched …
Golden Eagle Dietary Shifts Following Wildfire And Shrub Loss Have Negative Consequences For Nestling Survivorship, Julie A. Heath, Michael N. Kochert, Karen Steenhof
Golden Eagle Dietary Shifts Following Wildfire And Shrub Loss Have Negative Consequences For Nestling Survivorship, Julie A. Heath, Michael N. Kochert, Karen Steenhof
Biology Faculty Publications and Presentations
Wildfires and invasive species have caused widespread changes in western North America’s shrub-steppe landscapes. The bottom–up consequences of degraded shrublands on predator ecology and demography remain poorly understood. We used a before–after paired design to study whether Golden Eagle (Aquila chrysaetos) diet and nestling survivorship changed following wildfires in southwestern Idaho, USA. We assessed burn extents from 1981 to 2013 and vegetation changes between 1979 (pre-burn) and 2014 (post-burn) within 3 km of Golden Eagle nesting centroids. We measured the frequency and biomass of individual prey, calculated diet diversity indexes, and monitored nestling survivorship at 15 territories in …
The American Kestrel (Falco Sparverius) Genoscape: Implications For Monitoring, Management, And Subspecies Boundaries, Michaela Brinkmeyer, Julie A. Heath
The American Kestrel (Falco Sparverius) Genoscape: Implications For Monitoring, Management, And Subspecies Boundaries, Michaela Brinkmeyer, Julie A. Heath
Biology Faculty Publications and Presentations
Identifying population genetic structure is useful for inferring evolutionary process and comparing the resulting structure with subspecies boundaries can aid in species management. The American Kestrel (Falco sparverius) is a widespread and highly diverse species with 17 total subspecies, only 2 of which are found north of U.S./Mexico border (F. s. paulus is restricted to southeastern United States, while F. s. sparverius breeds across the remainder of the U.S. and Canadian distribution). In many parts of their U.S. and Canadian range, American Kestrels have been declining, but it has been difficult to interpret demographic trends without a …
Patterns And Mechanisms Of Heterogeneous Breeding Distribution Shifts Of North American Migratory Birds, Hanna M. Mccaslin, Julie A. Heath
Patterns And Mechanisms Of Heterogeneous Breeding Distribution Shifts Of North American Migratory Birds, Hanna M. Mccaslin, Julie A. Heath
Biology Faculty Publications and Presentations
There is widespread evidence that species distributions are shifting in response to climate change. Warming temperatures and climate niche constraints are hypothesized drivers of northward shifts in temperate migratory bird breeding distributions, but heterogeneity in the direction of distribution shifts suggests that the climate niche hypothesis does not explain all changes in distributions. We propose that: 1) changes in migration costs and benefits related to dampened seasonal differences between breeding and winter areas, 2) sensitivity to supplemental cues that affect duration of migration and onset of reproduction, 3) a latitudinal mismatch-driven fitness gradient, or a combination of these drivers may …
Dietary Plasticity In A Specialist Predator, The Gyrfalcon (Falco Rusticolus): New Insights Into Diet During Brood Rearing, Bryce W. Robinson, Travis L. Booms, Marc J. Bechard, David L. Anderson
Dietary Plasticity In A Specialist Predator, The Gyrfalcon (Falco Rusticolus): New Insights Into Diet During Brood Rearing, Bryce W. Robinson, Travis L. Booms, Marc J. Bechard, David L. Anderson
Biology Faculty Publications and Presentations
Climate and landscape change are expected to affect species’ distributions and interactions, with potentially harmful consequences for specialist predators. Availability of optimal prey can affect reproductive success in raptors, especially in the Arctic, where dramatic differences in prey availability occur both within and between years. However, behavioral responses of dietary specialist, resident predators such as Gyrfalcons (Falco rusticolus) to changes in prey availability remain poorly understood. To improve understanding of how climate-driven changes in prey availability may affect diet of avian predators in the Arctic, we characterized Gyrfalcon diet on the Seward Peninsula, Alaska, in 2014 and 2015 …
Assessing Patterns Of Barn Owl Tyto Alba Occupancy From Call Broadcast Surveys, Tempe Regan, Christopher J.W. Mcclure, James R. Belthoff
Assessing Patterns Of Barn Owl Tyto Alba Occupancy From Call Broadcast Surveys, Tempe Regan, Christopher J.W. Mcclure, James R. Belthoff
Biology Faculty Publications and Presentations
Owing to habitat loss, changes in farming practices, urbanization, and high mortality through vehicle collisions, barn owls Tyto alba are a species of conservation concern in portions of their range. This species can be secretive and difficult to survey, particularly away from breeding sites, so factors related to barn owl occurrence often remain unknown. We conducted nighttime broadcast surveys for barn owls during the early- and post-breeding seasons and used an occupancy modeling framework to understand how factors related to landcover, landscape features, and human development related to occupancy in southern Idaho, USA. We also assessed the effectiveness of using …
Flushing Responses Of Golden Eagles (Aquila Chrysaetos) In Response To Recreation, Robert J. Spaul, Julie A. Heath
Flushing Responses Of Golden Eagles (Aquila Chrysaetos) In Response To Recreation, Robert J. Spaul, Julie A. Heath
Biology Faculty Publications and Presentations
Disturbance because of human activity, including recreation on wildlands, can affect bird behavior which in turn can reduce breeding success, an important consideration for species of management concern. We observed Golden Eagles (Aquila chysaetos) during the breeding season to determine whether the probability of flushing was affected by the type of recreationist, distance to encounter, eagle nest attendance, or date. We monitored eagles in 23 nesting territories from distant (600-1,200 m) observation points and recorded recreation activity within 1,200 m of eagles in the Owyhee Front of southwestern Idaho. In most (86%, n = 270) encounters, eagles did …
Correlates Of Immune Defenses In Golden Eagle Nestlings, Benjamin M. Dudek, Julie A. Heath
Correlates Of Immune Defenses In Golden Eagle Nestlings, Benjamin M. Dudek, Julie A. Heath
Biology Faculty Publications and Presentations
An individual’s investment in constitutive immune defenses depends on both intrinsic and extrinsic factors. We examined how Leucocytozoon parasite presence, body condition (scaled mass), heterophil-to-lymphocyte (H:L) ratio, sex, and age affected immune defenses in golden eagle (Aquila chrysaetos) nestlings from three regions: California, Oregon, and Idaho. We quantified hemolytic-complement activity and bacterial killing ability, two measures of constitutive immunity. Body condition and age did not affect immune defenses. However, eagles with lower H:L ratios had lower complement activity, corroborating other findings that animals in better condition sometimes invest less in constitutive immunity. In addition, eagles with Leucocytozoon infections had higher …
Simulations Reveal The Power And Peril Of Artificial Breeding Sites For Monitoring And Managing Animals, Christopher J.W. Mcclure, Benjamin P. Pauli, Julie A. Heath
Simulations Reveal The Power And Peril Of Artificial Breeding Sites For Monitoring And Managing Animals, Christopher J.W. Mcclure, Benjamin P. Pauli, Julie A. Heath
Biology Faculty Publications and Presentations
Despite common use, the efficacy of artificial breeding sites (e.g., nest boxes, bat houses, artificial burrows) as tools for monitoring and managing animals depends on the demography of target populations and availability of natural sites. Yet, the conditions enabling artificial breeding sites to be useful or informative have yet to be articulated. We use a stochastic simulation model to determine situations where artificial breeding sites are either useful or disadvantageous for monitoring and managing animals. Artificial breeding sites are a convenient tool for monitoring animals and therefore occupancy of artificial breeding sites is often used as an index of population …
Forecasting Disturbance Effects On Wildlife: Tolerance Does Not Mitigate Effects Of Increased Recreation On Wild Lands, B. P. Pauli, R. J. Spaul, J. A. Heath
Forecasting Disturbance Effects On Wildlife: Tolerance Does Not Mitigate Effects Of Increased Recreation On Wild Lands, B. P. Pauli, R. J. Spaul, J. A. Heath
Biology Faculty Publications and Presentations
There is widespread evidence that human disturbance affects wildlife behavior, but long-term population effects can be difficult to quantify. Individual-based models (IBMs) offer a way to assess population-level, aggregate effects of disturbance on wildlife. We created TRAILS (Tolerance in Raptors and the Associated Impacts of Leisure Sports), an IBM that simulates interactions between recreationists and nesting raptors, to assess the effect of human disturbance on raptor populations and test if changes in tolerance to disturbance could mitigate negative consequences. We used behavioral and demographic data from golden eagles (Aquila chrysaetos), and recreation activity data to parameterize TRAILS and …
Nonmotorized Recreation And Motorized Recreation In Shrub-Steppe Habitats Affects Behavior And Reproduction Of Golden Eagles (Aquila Chrysaetos), Robert J. Spaul, Julie A. Heath
Nonmotorized Recreation And Motorized Recreation In Shrub-Steppe Habitats Affects Behavior And Reproduction Of Golden Eagles (Aquila Chrysaetos), Robert J. Spaul, Julie A. Heath
Biology Faculty Publications and Presentations
Different forms of outdoor recreation have different spatiotemporal activity patterns that may have interactive or cumulative effects on wildlife through human disturbance, physical habitat change, or both. In western North America, shrub-steppe habitats near urban areas are popular sites for motorized recreation and nonmotorized recreation and can provide important habitat for protected species, including golden eagles. Our objective was to determine whether recreation use (i.e., number of recreationists) or recreation features (e.g., trails or campsites) predicted golden eagle territory occupancy, egg-laying, or the probability a breeding attempt resulted in ≥1 offspring (nest survival). We monitored egg-laying, hatching and fledging success, …
Wintering Bald Eagle Count Trends In The Conterminous United States, 1986-2010, Wade L. Eakle, Laura Bond, Mark R. Fuller, Richard A. Fischer, Karen Steenhof
Wintering Bald Eagle Count Trends In The Conterminous United States, 1986-2010, Wade L. Eakle, Laura Bond, Mark R. Fuller, Richard A. Fischer, Karen Steenhof
Biomolecular Research Center Publications and Presentations
We analyzed counts from the annual Midwinter Bald Eagle Survey to examine state, regional, and national trends in counts of wintering Bald Eagles (Haliaeetus leucocephalus) within the conterminous 48 United States from 1986 to 2010. Using hierarchical mixed model methods, we report trends in counts from 11 729 surveys along 844 routes in 44 states. Nationwide Bald Eagle counts increased 0.6% per yr over the 25-yr period, compared to an estimate of 1.9% per yr from 1986 to 2000. Trend estimates for Bald Eagles were significant (P ≤ 0.05) and positive in the northeastern and northwestern U.S. …
Mitigation Effectiveness For Improving Nesting Success Of Greater Sage-Grouse Influenced By Energy Development, Christopher P. Kirol, Andrew L. Sutphin, Laura Bond, Mark R. Fuller, Thomas L. Maechtle
Mitigation Effectiveness For Improving Nesting Success Of Greater Sage-Grouse Influenced By Energy Development, Christopher P. Kirol, Andrew L. Sutphin, Laura Bond, Mark R. Fuller, Thomas L. Maechtle
Biology Faculty Publications and Presentations
Sagebrush Artemisia spp. habitats being developed for oil and gas reserves are inhabited by sagebrush obligate species--including the greater sage-grouse Centrocercus urophasianus (sage-grouse) that is currently being considered for protection under the U.S. Endangered Species Act. Numerous studies suggest increasing oil and gas development may exacerbate species extinction risks. Therefore, there is a great need for effective on-site mitigation to reduce impacts to co-occurring wildlife such as sage-grouse. Nesting success is a primary factor in avian productivity and declines in nesting success are also thought to be an important contributor to population declines in sage-grouse. From 2008 to 2011 we …