Ornithology Commons^™

The Distribution And Reproductive Success Of The Western Snowy Plover Along The Central And Southern Oregon Coast - 2025, David J. Lauten, Kathleen A. Castelein, Mary Lee, Jessica Burr, Marty R. Mccamant, Eleanor P. Gaines

Institute for Natural Resources Publications

We monitored the distribution, abundance and productivity of the federally threatened Western Snowy Plover (Anarhynchus nivosus nivosus) along the central and south coast of Oregon from 3 April – 10 September 2025. We surveyed and monitored plover activity in a project area that included, from north to south, Sutton Beach, Siltcoos River estuary, the Dunes Overlook, North Tahkenitch Creek, Tenmile Creek, Coos Bay North Spit (CBNS), Bandon Snowy Plover Management Area (SPMA), New River Habitat Restoration Area (HRA) and adjacent lands, and Floras Lake. Our objectives for the project area in 2025 were to: 1) estimate the size of the …

Oregon State Rank Assessment For Brandt's Cormorant (Phalacrocorax Penicillatus), Misty Nelson, Eleanor P. Gaines

Institute for Natural Resources Publications

Oregon state conservation status assessment for Brandt's cormorant (Phalacrocorax penicillatus) using NatureServe methodology, 2024.

Oregon State Rank Assessment For Black-Backed Woodpecker (Picoides Arcticus), Eleanor P. Gaines

Institute for Natural Resources Publications

Oregon state conservation status assessment for Black-backed woodpecker (Picoides arcticus) using NatureServe methodology, 2024.

Assessment Of Avian Community Structure And Habitat Connectivity In The Fanno Creek Corridor Bird Surveys, Habitat Assessment, And Management Recommendations, Grace Hall

Environmental Science and Management Professional Master's Project Reports

Urbanization can significantly impact habitat quality and connectivity for avian communities, decreasing species richness and diversity. However, in highly fragmented habitats, urban parks and riparian zones can provide important habitat corridors for birds that facilitate movement and access to essential resources. On the west side of greater Portland, Oregon, Fanno Creek may serve as a habitat corridor for birds and other local wildlife.

Fanno Creek is a 25-kilometer tributary of the Tualatin River that runs through the cities of Portland, Beaverton, Tigard, and Durham in northwestern Oregon. The land surrounding the creek includes residential, commercial, and industrial properties as well …

Oregon State Rank Assessment For Oak Titmouse (Baeolophus Inornatus), Misty Nelson

Institute for Natural Resources Publications

Oregon state conservation status assessment for Oak Titmouse (Baeolophus inornatus) using NatureServe methodology, 2024.

The Distribution And Reproductive Success Of The Western Snowy Plover Along The Central And Southern Oregon Coast - 2023, David J. Lauten, Kathleen A. Castelein, Mary Lee, Jacey Corrente, Marty R. Mccamant, Eleanor P. Gaines

Institute for Natural Resources Publications

We monitored the distribution, abundance and productivity of the federally threatened Western Snowy Plover (Anarhynchus nivosus nivosus) along the central and south coast of Oregon from 4 April – 15 September 2023. We surveyed and monitored plover activity in a project area that included, from north to south, Sutton Beach, Siltcoos River estuary, the Dunes Overlook, North Tahkenitch Creek, Tenmile Creek, Coos Bay North Spit, Bandon Snowy Plover Management Area, New River Habitat Restoration Area (HRA) and adjacent lands, and Floras Lake. Our objectives for the project area in 2023 were to: 1) estimate the size of the adult Snowy …

Oregon State Rank Assessment For Yellow-Billed Cuckoo (Coccyzus Americanus), Misty Nelson

Institute for Natural Resources Publications

Oregon state conservation status assessment for Yellow-billed cuckoo (Coccyzus americanus) using NatureServe methodology, 2023.

Oregon State Rank Assessment For Blue-Gray Gnatcatcher (Polioptila Caerulea), Misty Nelson

Institute for Natural Resources Publications

Oregon state conservation status assessment for Blue-gray gnatcatcher (Polioptila caerulea) using NatureServe methodology, 2023.

Oregon State Rank Assessment For Lark Sparrow (Chondestes Grammacus), Misty Nelson

Institute for Natural Resources Publications

Oregon state conservation status assessment for Lark sparrow (Chondestes grammacus) using NatureServe methodology, 2023.

Oregon State Rank Assessment For American Three-Toed Woodpecker (Picoides Dorsalis), Misty Nelson

Institute for Natural Resources Publications

Oregon state conservation status assessment for American three-toed woodpecker (Picoides dorsalis) using NatureServe methodology, 2023.

The Distribution And Reproductive Success Of The Western Snowy Plover Along The Oregon Coast - 2022, David J. Lauten, Kathleen A. Castelein, Daniel Farrar, Mary Lee, Eleanor P. Gaines

Institute for Natural Resources Publications

We monitored the distribution, abundance and productivity of the federally threatened Western Snowy Plover (Charadrius nivosus nivosus) along the central and south coast of Oregon from 1 April – 15 September 2022. We surveyed and monitored plover activity in a project area that included, from north to south, Sutton Beach, Siltcoos River estuary, the Dunes Overlook, North Tahkenitch Creek, Tenmile Creek, Coos Bay North Spit, Bandon Snowy Plover Management Area, New River Habitat Restoration Area (HRA) and adjacent lands, and Floras Lake. Our objectives for the project area in 2022 were to: 1) estimate the size of the adult Snowy …

Urban Nesting Biology, Population Viability And Ecology Of The Willow Flycatcher, Empidonax Traillii, Stephanie Alexandra Byrne Doorly

Dissertations and Theses

Reproductive success, in any species, relies both on the habitat utilized to reproduce and on the successful reproductive output of individual animals within a population. Populations in turn rely on the reproductive fitness of the individual. Whether populations remain stable, grow, or decline ultimately relies on the combined reproductive output of the individuals within that population.

We studied the Willow Flycatcher (Empidonax traillii; henceforth WIFL), a well-studied Neartic-Neotropical migrant passerine whose breeding range extends from the east to west coast of North America. Across much of their range, and in particular in the western regions, breeding population are …

Inter- And Intracontinental Migration By The Eastern Kingbird (Tyrannus Tyrannus), Daniel H. Kim, Lucas J. Redmond, James R. Fox, Michael T. Murphy

Biology Faculty Publications and Presentations

We recovered 12 archival geolocators deployed on Eastern Kingbirds (Tyrannus tyrannus) breeding in New York (NY; n¼3, 2 with 2 years of data), Nebraska (NE; n¼6, 1 with 2 years of data), and Oregon (OR; n¼3) to describe migratory routes, timing and rates of migration, nonbreeding season distributions, and migratory connectedness. NY fall migrants migrated along the Atlantic coast to Florida, flew either nonstop across the Gulf of Mexico (GoM; 2 of 3 birds) or stopped once along the way (Cuba and Cayman Islands in different years) to land in Yucatan/Central America. Fall birds from NE and OR arrived at …

Effects Of Management For Productivity On Adult Survival Of Snowy Plovers, Eleanor P. Gaines, Stephen J. Dinsmore, Michael T. Murphy

Biology Faculty Publications and Presentations

Understanding the factors contributing to variation in demographic parameters and their influences on population growth is fundamental to effective conservation of small populations, but this information is often not available. Among shorebirds, population growth is generally most sensitive to changes in adult survival so understanding the factors affecting this vital rate is important. We used a long‐term mark–resight dataset and Program MARK to examine the effect of management actions, initiated to improve nesting productivity, on adult survival in a threatened population of Snowy Plovers (Charadrius nivosus ) in Oregon, USA. Apparent adult survival averaged 0.71 ± 0.01 (SE), but …

Follow The Rain? Environmental Drivers Of Tyrannus Migration Across The New World, Maggie P. Macpherson, Alex E. Jahn, Michael T. Murphy, Daniel H. Kim, Victor R. Cueto, Diego T. Tuero, Elliot D. Hill

Biology Faculty Publications and Presentations

Predictable seasonal changes in resources are thought to drive the timing of annual animal migrations; however, we currently understand little about which environmental cues or resources are tracked by different migratory bird species across the planet. Understanding which environmental cues or resources birds track in multiple migratory systems is a prerequisite to developing generalizable conservation plans for migratory birds in a changing global environment. Within the New World, climatic differences experienced by Nearctic–Neotropical migratory (NNM; i.e. breed in North America and spend the nonbreeding period in the Neotropics) and Neotropical austral migratory (NAM; i.e. breed and spend the nonbreeding period …

Winter Diet Of Bobolink, A Long-Distance Migratory Grassland Bird, Inferred From Feather Isotopes, Rosalind B. Renfrew, Jason M. Hill, Daniel H. Kim, Christopher Romanek, Noah G. Perlut

Biology Faculty Publications and Presentations

Effective conservation of migratory bird populations depends on advancements in our understanding of processes throughout the life cycle. Fundamental information about wintering ecology (e.g., habitat use and diet composition) remains limited, which limits assessment of threats to populations during winter. Bobolink (Dolichonyx oryzivorus) is a year-round grassland obligate and Nearctic-Neotropical migrant that undergoes 2 complete molts each year, including a complete prealternate molt on the South American wintering grounds. This unusual winter molt provides a rare opportunity to examine, using stable isotope analysis, the timing and contribution of foraging resources in the Bobolink diet prior to northbound migration from disparate …

Factors Affecting Snowy Plover Chick Survival In A Managed Population, Stephen J. Dinsmore, Eleanor P. Gaines, Scott F. Pearson, David J. Lauten, Kathleen J. Castelein

Institute for Natural Resources Publications

Understanding survival of precocial chicks in the period immediately following hatching has important conservation implications because population growth is often sensitive to post-hatching survival. We studied federally threatened Western Snowy Plover (Charadrius nivosus nivosus) broods at the northern limit of their range in coastal Oregon (n ¼ 1,157) and Washington (n ¼ 84) from 1991 to 2011 in an attempt to understand seasonal, annual, and spatial patterns of chick survival. In Oregon, plover chick survival increased with age, varied between sites, and was greater at sites with predator management. The mean probability of surviving from hatch to fledging at 28 …

Empirical Evidence For The Scale Dependence Of Biotic Interactions, Jonathan Belmaker, Phoebe Zarnetske, Sara Zonneveld, Sydne Record, Angela L. Strecker, Lydia Beaudrot

Environmental Science and Management Faculty Publications and Presentations

Aim: Although it is recognized that ecological patterns are scale dependent, the exact scales over which specific ecological processes operate are still a matter of controversy. In particular, understanding the scales over which biotic interactions operate is critical for predicting changes in species distributions in the face of the ongoing biodiversity crisis. It has been hypothesized that biotic interactions operate predominately at fine grains, yet this conjecture has received relatively little empirical scrutiny. We use US woodpeckers as a model system to assess the relative importance of biotic interactions, environmental suitability and geographic proximity to other intraspecific occurrence sites, …

Experimental Analysis Of Nest-Site Choice And Its Relationship To Nest Success In An Open-Cup–Nesting Passerine, Sarah Cancellieri, Michael T. Murphy

Biology Faculty Publications and Presentations

Nest placement presumably reflects selection for secure sites to minimize failure. Most tests of this hypothesis, however, have failed to support it. We used artificial nests (ARTs) to experimentally evaluate nest-site-choice behavior by an open-cup–nesting bird, the Eastern Kingbird (Tyrannus tyrannus). In 2010 and 2011, we placed ARTs in trees in the riparian zone at Malheur National Wildlife Refuge, Oregon, USA, to test whether (1) characteristics describing the physical location in trees of used and unused ARTs differed, (2) used ART sites more closely resembled naturally chosen sites, (3) successful natural nests (NATs) and successful ARTs were similarly …

Residential Edges As Ecological Traps: Postfledgling Survival Of A Ground-Nesting Passerine In A Forested Urban Park, Amy A. Shipley, Michael T. Murphy, Adam H. Elzinga

Biology Faculty Publications and Presentations

Substantial offspring mortality can occur during the postfledging period of birds, but few postfledging survival studies have been conducted within the context of habitat suitability. We conducted a 2-year radiotelemetry study of Spotted Towhee (Pipilo maculatus) reproductive success and fledgling survival in a 24-ha forested park in a residential area of Lake Oswego, Oregon. In corroboration of previous research on this species, we found (1) that Spotted Towhees nested closer to the edge between the park and residential neighborhoods than expected by chance, and (2) that pairs nesting near edges produced the largest and most offspring. However, fates were reversed …

Migration Timing And Wintering Areas Of Three Species Of Flycatchers (Tyrannus) Breeding In The Great Plains Of North America, Alex E. Jahn, Victor R. Cueto, James W. Fox, Michael S. Husak, Daniel H. Kim, Diane V. Landoll, Jesús Pinto Ledezma, Heather K. Lepage, Douglas J. Levey, Michael T. Murphy, Rosalind B. Renfrew

Biology Faculty Publications and Presentations

Descriptions of intra- and interspecific variation in migratory patterns of closely related species are rare yet valuable because they can help assess how differences in ecology and life-history strategies drive the evolution of migration. We report data on timing and location of migration routes and wintering areas, and on migratory speed and phenology, of Eastern Kingbirds (Tyrannus tyrannus) from Nebraska and Oklahoma and of Western Kingbirds (T. verticalis) and Scissor-tailed Flycatchers (T. forficatus) from Oklahoma. Eastern Kingbirds primarily departed the breeding site in September, migrating to the Amazon Basin (Bolivia and Brazil), >6,400 km …

An Experimental Investigation Of Nest Reuse And Nest Site Selection In An Open-Cup Nesting Passerine, Sarah A. Cancellieri

Dissertations and Theses

Eastern Kingbirds (Tyrannus tyrannus) breed from coast to coast in North America and build open-cup nests in trees. They have been extensively studied across most of their range and have only on occasion been documented to reuse a nest from a previous season. However, at Malheur National Wildlife Refuge (MNWR), located in southeastern Oregon, ~10 % of female Eastern Kingbirds reuse old nests of mainly American Robins (Turdus migratorius). In an attempt to address why nest reuse is so common at MNWR, I used artificial nests to evaluate two hypotheses as to why nest reuse is common in this breeding …

Site Selection By Migratory Shorebirds In Oregon Estuaries Over Broad And Fine Spatial Scales, Aileen Kilpatrick Miller

Dissertations and Theses

Many migratory shorebirds rely on estuaries as stop-over sites to refuel during migration, and the loss of stop-over sites is a primary threat to shorebird populations on the West Coast of the United States (e.g. Calidris alpina pacifica, C. mauri). Conservation and research has focused on the largest of these sites; however, smaller estuaries also host thousands of migratory shorebirds. Furthermore, the reasons for site selection are largely unknown. Estuarine inter-tidal microhabitats are non-uniform and both abiotic and biotic factors may serve as predictors of whether an abundance of shorebirds will use a site. I investigated shorebird site selection on …

The Breeding Biology Of The Northern Pygmy Owl: Do The Smallest Of The Small Have An Advantage?, John F. Deshler, Michael T. Murphy

Biology Faculty Publications and Presentations

We explored the breeding biology of the Northern Pygmy-Owl (Glaucidium gnoma) from 2007 to 2009 in a forested reserve in Portland, Oregon. Large body size is often assumed to give animals reproductive advantages, and we tested whether body size affected timing of breeding and examined variation in diet, breeding date, clutch size, and reproductive success to explore whether the presumed benefits of large body size are evident in this species. The average size of 13 clutches was 5.8, and nest success was high (92%); 22 successful nests fledged an average of 5.2 young. Dates of first laying varied …

Multistate Mark-Recapture Analysis Reveals No Effect Of Blood Sampling On Survival And Recapture Of Eastern Kingbirds (Tyrannus Tyrannus), Lucas J. Redmond, Michael T. Murphy

Biology Faculty Publications and Presentations

The experimentally supported and prevailing opinion is that blood sampling has few to no long-term effects on survival of birds when conducted properly, and blood sampling has become a vital addition to the toolbox of many ornithologists. However, many of the studies that concluded that blood sampling had negligible effects on birds used approaches that did not account for temporary emigration and probability of capture. To date, the only study to have done so found that blood sampling had a strong negative effect on survival. We conducted a mark–recapture analysis of 8 years of banding and bleeding data on Eastern …

Fecal-Sac Ingestion By Spotted Towhees, Jenny E. Mckay, Michael T. Murphy, Sarah Bartos Smith, Jennifer K. Richardson

Biology Faculty Publications and Presentations

Altricial nestlings encase excrement in fecal sacs that parents remove by either ingesting them or transporting them away from the nest. Ingestion may allow energetically or nutritionally deprived parents to recapture energy or nutrients that might be lost because of nestlings' inefficient digestion (the "parental-nutrition hypothesis"), but ingestion may also permit parents to avoid flights from the nest that interfere with parental care (e.g., brooding young; the "economic-disposal hypothesis"). We used a hypothetico-deductive approach to test the two hypotheses' ability to account for fecal-sac ingestion by the Spotted Towhee (Pipilo maculatus). We confirmed the parental-nutrition hypothesis' predictions that …

Lifetime Reproductive Success Of Female Eastern Kingbirds (Tyrannus Tyrannus): Influence Of Lifespan, Nest Predation And Body Size, Michael T. Murphy

Biology Faculty Publications and Presentations

I report on the lifetime reproductive success (LRS) of female Eastern Kingbirds (Tyrannus tyrannus) in central New York. I investigated the major correlates of LRS and specifi cally tested the hypothesis that small body size yields reproductive benefi ts. Lifetime reproductive success varied widely: 15–20% of females failed to fledge young over their life, whereas 50% of young were fledged by 20% of females. Female lifespan varied between one and eight years, and females that died after one breeding season tended to be smaller-bodied than long-lived females (≥2 seasons). I therefore conducted analyses of LRS for the entire sample and …

A Cautionary Tale: Cryptic Sexual Size Dimorphism In A Socially Monogamous Passerine, Michael T. Murphy

Biology Faculty Publications and Presentations

Among socially monogamous birds, standard metrics suggest that males are only ∼5% larger than females. An untested assumption is that, with the exception of reproductive systems, males and females are scaled mirror images of one another. I used external morphological and skeletal data, and information on muscle mass and organ size, to test this assumption in a population of breeding Eastern Kingbirds (Tyrannus tyrannus). Male and female Eastern Kingbirds exhibited no differences in body mass or standard measures of size, except in a longer (∼6%) wing chord and tail in males. However, keel length, a character rarely measured …

Nest Reuse By Eastern Kingbirds: Adaptive Behavior Or Ecological Constraint?, Lucas J. Redmond, Michael T. Murphy, Amy C. Dolan

Biology Faculty Publications and Presentations

The reuse of old nests by open-cup nesting passerines is a seemingly rare but potentially adaptive behavior if, as a consequence, females begin to breed earlier, lay larger clutches, or fledge more young. We report an unusually high rate of nest reuse (~10% of 341 nests) for Eastern Kingbirds (Tyrannus tyrannus) breeding at Malheur National Wildlife Refuge, Oregon. We found no difference in availability of nesting habitat or food abundance in territories in which nests were and were not reused. We also found no support for the hypotheses that kingbirds benefited from nest reuse by breeding earlier, laying …

Avian Population Trends Within The Evolving Agricultural Landscape Of The Eastern And Central United States, Michael T. Murphy

Biology Faculty Publications and Presentations

State-level Breeding Bird Survey (1980-1998) and U.S. Department of Agriculture statistics were used to test the hypothesis that changes in agricultural land use within the eastern and central U.S. have driven population trends of grassland and shrub habitat birds over the past two decades. The degree to which population trends differed between grassland and shrub habitats was evaluated with respect to migratory and nesting behavior. Grassland birds declined significantly between 1980 and 1999, but, on average, shrub habitat species did not. Grassland-breeding, long-distance migrants exhibited the strongest negative trends. Most species (78%; n = 63) exhibited at least one significant …