Piranga Ludoviciana Research Articles

Emergence phenology of the giant salmonfly and responses by birds in Idaho river networks

Emergence of adult aquatic insects from rivers is strongly influenced by water temperature, and emergence timing helps to determine the availability of this ephemeral food resource for birds and other terrestrial insectivores. It is poorly understood how spatial heterogeneity in riverine habitat mediates the timing of emergence. Such spatiotemporal variation may have consequences for terrestrial insectivores that rely on aquatic-derived prey resources. We investigated emergence phenology of the giant salmonfly, Pteronarcys californica, at three spatial scales in two Idaho river networks. We examined the influence of tributary confluences on salmonfly emergence timing and associated insectivorous bird responses. Salmonfly emergence timing was highly variable at the basin-scale during the period we sampled (May–June). Within sub-drainage pathways not punctuated by major tributaries, emergence followed a downstream-to-upstream pattern. At the scale of reaches, abrupt changes in thermal regimes created by 10 major tributary confluences created asynchrony in emergence of 1–6 days among the 20 reaches bracketing the confluences. We observed 10 bird species capturing emerged salmonflies, including 5 species typically associated with upland habitats (e.g., American robin, red-tailed hawk, American kestrel) but that likely aggregated along rivers to take advantage of emerging salmonflies. Some birds (e.g., Lewis’s woodpecker, western tanager, American dipper) captured large numbers of salmonflies, and some of these fed salmonflies to nestlings. Emergence asynchrony created by tributaries was associated with shifts in bird abundance and richness which both nearly doubled, on average, during salmonfly emergence. Thermal heterogeneity in river networks created asynchrony in aquatic insect phenology which prolonged the availability of this pulsed prey resource for insectivorous birds during key breeding times. Such interactions between spatial and temporal heterogeneity and organism phenology may be critical to understanding the consequences of fluxes of resources that link water and land. Shifts in phenology or curtailment of life history diversity in organisms like salmonflies may have implications for these organisms, but could also contribute to mismatches or constrain availability of pulsed resources to dependent consumers. These could be unforeseen consequences, for both aquatic and terrestrial organisms, of human-driven alteration and homogenization of riverscapes.

Diet-Related Plumage Erythrism in the Western Tanager and Other Western North American Birds

Consumption of the berries of two exotic bush honeysuckles (genus Lonicera) containing the red carotenoid pigment rhodoxanthin has resulted in abnormal erythristic plumages in several species of birds in eastern North America. Here we report 12 examples of plumage erythrism in the Western Tanager (Piranga ludoviciana), in both live birds (5) and museum specimens (7), that we suspect have the same etiology. The erythristic tanagers feature overtly orange to red feathers variously scattered on the head, rump, wing coverts, and/or underparts, areas of the plumage normally colored by carotenoid pigments. All were in their year of hatching, so the reddened feathers, including replaced median coverts with orange tips, represent formative plumage grown on or near the breeding grounds where berries containing rhodoxanthin are available. By contrast, adult Western Tanagers undergo body molt primarily in the Mexican monsoon region in fall and on their winter grounds in early spring where bush honeysuckles are nonexistent. We also report examples of Red-breasted Sapsuckers (Sphyrapicus ruber) with anomalous red pigmentation on their backs and of Cedar Waxwings (Bombycilla cedrorum) with orange tail bands, as previously documented in the East. In these species, the reddened areas are typically yellow or green, colors based on carotenoid pigments that can be altered through the consumption of fruits containing rhodoxanthin. We conclude that these reddened feathers are the result of the consumption of honeysuckle berries or possibly the red arils of the Pacific Yew (Taxus brevifolia), representing a first report of diet-related erythrism in western North America.

Overlap of Molt and Fall Migration of the Western Tanager and Warbling Vireo in Southern California

Overlap of Molt and Fall Migration of the Western Tanager and Warbling Vireo in Southern California

Posible incidencia de viruela u otro patógeno de aves en Guatemala

Durante enero y febrero de 2019 hicimos observaciones casuales y documentamos aves con lesiones macroscópicas, aparentemente por viruela o algún tipo de tumor en la cabeza. Los individuos eran de ocho especies (cinco migratorias y tres residentes), las observamos en tres localidades distintas de Guatemala. Las especies migratorias fueron Passerina ciris (Cardinalidae), Catharus ustulatus (Turdidae), Oreothlypis peregrina (Parulidae), Piranga ludoviciana (Cardinalidae) y Pheucticus ludovicianus (Cardinalidae), y las residentes, Cyanerpes cyaneus (Thraupidae), Euphonia luteicapilla (Fringilidae) y Thraupis episcopus (Thraupidae). Aunque las lesiones se ven similares a las de la viruela, ninguno de estos individuos fue capturado, por esta razón no se ha establecido un diagnóstico definitivo. Actualmente estamos trabajando en un proyecto de investigación para tomar muestras patológicas y confirmar el diagnóstico; sin embargo, consideramos que la comunidad científica debe estar alerta respecto a esta situación, pues tanto las especies migratorias como las residentes están siendo afectadas y todavía no sabemos las consecuencias que esto podría tener en la avifauna y los ecosistemas en general.

A new species of Proctophyllodes Robin, 1868 (Acari: Proctophyllodidae) from two tanagers of the genus Piranga Vieillot (Passeriformes: Cardinalidae) from North America

ABSTRACTA new feather mite species, Proctophyllodes pirangae sp. n. (Acari: Proctophyllodidae) is described from two tanagers of the genus Piranga Vieillot, 1808 (Passeriformes: Cardinalidae) in North America: the Scarlet Tanager, Piranga olivacea (Gmelin) and the Western Tanager, Piranga ludoviciana (Wilson) (Passeriformes: Cardinalidae) from North America. The new species belongs to the anthi species group and differs from the most similar species, Proctophyllodes polyxenus Atyeo and Braasch, by having in males, the aedeagus and genital sheath extending to or slightly beyond the level of setae g, the anterior margin of the opisthogastric shield shallowly concave, and its posterior margin nearly square-shaped, and the lamellae smaller; in females, both the lobar cleft and the transverse band of soft tegument at level of setae h1 are considerably narrower.www.zoobank.org/urn:lsid:zoobank.org:pub:29B3D157-8114-48EC-AF31-61A99F6D0C3B

Using automated recorders and occupancy models to monitor common forest birds across a large geographic region

ABSTRACTAutomated recorders and occupancy models can be used together to monitor population trends of multiple avian species across a large geographic region. Automated recorders are an attractive method for monitoring birds, because they leave a record that can be independently validated and multiple units can be programmed to repeatedly survey different locations at the same daily times. We assessed the use of automated recorders and single‐species, single‐season occupancy models to monitor common forest birds across a 5.4‐million‐ha region of northern California. Using a survey protocol of 5‐minute recordings at 3 times of the morning repeated over 3 consecutive days at 453 sites, we detected 32 species at >10% of these sites. Five of these species (Steller's jay [Cyanocitta stelleri], mountain chickadee [Poecile gambeli], red‐breasted nuthatch [Sitta canadensis], dark‐eyed junco [Junco hyemalis], and western tanager [Piranga ludoviciana]) were dominant with occupancies >0.5. We also modeled occupancy associations with elevation and canopy cover for brown creeper (Certhia americana), MacGillivray's warbler (Geothlypis tolmiei), and western tanager and found the environmental conditions at which occupancy was maximized differed by up to 399 m in elevation and 17.9% canopy cover for these species. Given a sampling effort of 100 new sites per year, we demonstrated 80% power (α = 0.1) to detect occupancy declines as small as 2.5% per year over 20 years for the 32 most common species. The effective radius of automated recorder surveys was approximately 50 m. In a field test, surveys conducted concurrently using automated recorders and point counts yielded similar occupancy estimates despite differences in detection probability. Our results suggest that automated recorders, used alone or in conjunction with point counts, can provide a practical means of monitoring common forest birds across a large geographic area. © 2014 The Wildlife Society.

Costs of multiple parasitism for an avian brood parasite, the Brown-headed Cowbird (Molothrus ater)

The Brown-headed Cowbird ( Molothrus ater (Boddaert, 1783)) is a generalist brood parasite that often lays into nests that contain conspecific eggs. Although it has often been assumed that this multiple parasitism reduces Cowbird survival, this has rarely been evaluated. We measured Cowbird survival in nests of the Blue-gray Gnatcatcher ( Polioptila caerulea (L., 1766)), Plumbeous Vireo ( Vireo plumbeus Coues, 1866), and Western Tanager ( Piranga ludoviciana (A. Wilson, 1811)) in New Mexico, USA. Our objectives were to measure the costs of intraspecific competition on Cowbird survival in multiply-parasitized nests, evaluate if these costs were related to host size, and to compare the costs of multiple parasitism relative to other mortality sources that occur over the entire nesting cycle. Intraspecific competition reduced Cowbird survival during the nestling period in nests of all three hosts, and was of particular importance in nests of the two smaller hosts. When all sources of egg mortality were considered, however, the costs of multiple parasitism were small compared with the large effects of predation and nest desertion. Given that multiple parasitism reduces Cowbird egg survival, it is unclear why Cowbirds multiply-parasitize. Possible explanations depend on an improved understanding of fecundity and level of host nest selectivity by female Cowbirds.

Four new species of Aulonastus Kethley, 1970 (Acari: Syringophilidae) from North American passerines

Four new species belonging to Aulonastus Kethley, 1970 (Acari: Prostigmata: Syringophilidae), which are found inside the quills of body feathers of North American passerines (Aves: Passeriformes), are described and figured: A. emberizicus n. sp. from Ammodramus savanarum (Gmelin) (Emberizidae) (type-host) in Texas, Zonotrichia atricapilla (Gmelin) (Emberizidae) in California and Passerculus sandwichensis (Gmelin) (Emberizidae) in Texas; A. euphagus n. sp. from Euphagus cyanocephalus (Wagler) (Icteridae) in California; A. pirangus n. sp. from Piranga ludoviciana (Wilson) (Cardinalidae) in California; and A. sturnellus n. sp. from Sturnella magna (Linnaeus) (Icteridae) in Texas. A key to females of the known species of Aulonastus is presented.

Community-level patterns of population recruitment in a generalist avian brood parasite, the brown-headed cowbird

The brown-headed cowbird (Molothrus ater) is a generalist brood parasite that typically parasitizes many host species in a single bird community. Population recruitment in a generalist parasite should be diverse with respect to host species; however, host-specific rates of cowbird recruitment have not been reported in any host community, and the determinants of host quality are poorly known. We studied the combined influence of parasitism level, nest abundance, and host quality on community-level patterns of cowbird recruitment in New Mexico, USA. Our objectives were to: (1) evaluate patterns of host use and quality; (2) compare cowbird egg investment and recruitment among host species; (3) identify host species of most importance to cowbird recruitment. Cowbirds parasitized 11 host species, with five "major" hosts experiencing high parasitism levels (>or=1 cowbird egg/nest) and six minor hosts experiencing low parasitism levels (<0.3 cowbird eggs/nest). Parasitism level was not correlated with host species abundance, host mass, host nestling period length, or host success at fledging cowbirds. However, tree-nesting hosts were parasitized more than ground-nesters, and foliage-gleaners more than sally-foragers and ground-foragers. Average estimated survival to fledging of cowbird eggs laid in active host nests was 0.19. Cowbird recruitment was diverse with respect to hosts but was less evenly distributed across the host community than was cowbird egg investment because western tanagers (Piranga ludovicianus) fledged cowbirds more successfully than other hosts. This success in western tanagers was due to high cowbird survivorship in tanager nests and may be associated with the larger body size of tanagers relative to other hosts.

An Updated Catalogue of the Birds from the Carpinteria Asphalt, Pleistocene of California

Abstract Published accounts of the Carpinteria avifauna, collected from an upper Pleistocene asphalt deposit near Carpinteria, California, were based on only a small portion of the collection. The present paper is a complete review of the avifauna, including information on previously unpublished and unidentified material. The avifauna contains 79 species, twenty-seven of which have been added to the published avifauna from the deposits. Included among these are the first fossil records of Rallus limicola, Tringa melanoleuca, Tyrannus verticalis, and Piranga ludoviciana. Specimens from the deposit previously assigned to Corvus caurinus are referred to C. brachyrhynchos.

Mites of the GenusTorotrogla(Prostigmata: Syringophilidae) From North American Passerines

Five new quill mite species of the genus Torotrogla Kethley, 1970 (Acari: Syringophilidae) are described from North American passerines: T. aphelocoma sp.n. from Aphelocoma californica (Corvidae) and T. cardinalis sp.n. from Cardinalis cardinalis (Cardinalidae) in Texas; and T. coccothraustes sp.n. from Coccothraustes vespertinus (Fringillidae), T. cyanocitta sp.n. from Cyanocitta stelleri (Corvidae), and T. piranga sp.n. from Piranga ludoviciana (Thraupidae) in California. A key to females of all known Torotrogla spp. and a table with their host associations and distributions are given.

Effects of Parasitism by Brown-Headed Cowbirds (MOLOTHRUS ATER) on Reproductive Success of Three Frequent Hosts in New Mexico

Abstract We studied effects of parasitism by brown-headed cowbirds (Molothrus ater) on three frequent hosts from a pinyon-juniper (Pinus-Juniperus) community in New Mexico. During 1993–1999 and 2001–2002, we measured frequencies of parasitism and examined how differences in size of host, life-history traits, and behavior, as well as aspects of behavior of brown-headed cowbirds (i.e., removal of eggs of host and multiple parasitism), influenced reproductive success of blue-gray gnatcatchers (Polioptila caerulea), plumbeous vireos (Vireo plumbeus), and western tanagers (Piranga ludoviciana). Brown-headed cowbirds parasitized 79% of 288 nests of blue-gray gnatcatchers, 84% of 170 nests of plumbeous vireos, and 76% of 129 nests of western tanagers. Parasitism reduced productivity of hosts through removal of eggs, reduced hatching success, reduced survival of nestlings, and desertion of nest. Relative to unparasitized nests, size of clutch of singly parasitized nests was reduced, on average, by 0.3 eggs for th...

Bird occupancy and richness in ponderosa pine forests with contrasting forest structure and fire historyThis article is one of a selection of papers from the Special Forum on Ecological Studies in Interior Ponderosa Pine — First Findings from Blacks Mountain Interdisciplinary Research.

We compared the effects of two contrasting silvicultural treatments and prescribed fire on bird occupancy at Blacks Mountain Experimental Forest. Each silvicultural treatment was applied to two approximately 100 ha units within each of three blocks. Prescribed burning was applied to one-half of each silvicultural treatment in a split-plot design. Occupancy was estimated at eight points in each plot for 11 bird species and three foraging guilds (bark gleaners, woodpeckers, and foliage gleaners). The frequencies of species detections on the point counts were used to estimate species richness on each plot. Occupancy did not differ among treatments for any of the guilds. Four of the 11 bird species, the American robin ( Turdus migratorius L., 1766), the chipping sparrow ( Spizella passerina (Bechstein, 1798)), the white-breasted nuthatch ( Sitta carolinensis Latham, 1790), and the western tanager ( Piranga ludoviciana (A. Wilson, 1811)), showed responses to the treatments. Species richness did not differ between the silvicultural or the burn treatments. The general lack of response of the bird community to the silvicultural and burn treatments is likely a result of the relatively large size of the trees and snags retained on both silvicultural treatments, the low intensity of the prescribed burns, and the lack of a strong contrast in tree density between the silvicultural treatments.

Short‐Term Response of Land Birds to Ponderosa Pine Restoration

AbstractWe monitored the short‐term (&gt;3 years) response of land birds to forest restoration treatments in Ponderosa pine forests located on the east slope of the North Cascade Range. Restoration treatments were designed to create stand structure and composition similar to pre‐settlement forests, which were influenced by a frequent fire regime. Overall, avian community composition was changed as a result of the treatments. Cassin’s Finch, Chipping Sparrow, and Yellow‐rumped Warbler were found at higher densities in treated stands, whereas Mountain Chickadee, Western Tanager, and Red‐breasted Nuthatch had higher densities in untreated stands. White‐headed Woodpecker and Western Bluebird were only detected in the treated stands. Brown‐headed Cowbird showed no response to treatments. We detected changes in the density of four of five foraging guilds in response to restoration treatments. Tree seedeaters, low understory and ground insectivores, and aerial insectivores all increased in density in treated stands. Overall, bark insectivores showed no density response to treatments. Tree foliage insectivore density was lower in treated than in untreated stands. Overall avian density, density of neotropical migrants, and density of some focal species were higher in treated stands. Monitoring should be continued to understand the longer‐term (5–10 year) responses of land birds and to guide future forest restoration efforts.

HOST USE BY SYMPATRIC COWBIRDS IN SOUTHEASTERN ARIZONA

Abstract Sympatric avian brood parasites may compete for the same nests to parasitize. Host-resource partitioning, or “alloxenia,” is exhibited by several Old World cuckoos where they are sympatric in Africa, Japan, and Australia. I examined host use by sympatric Brown-headed Cowbirds (Molothrus ater) and Bronzed Cowbirds (M. aeneus) from 1997 to 1999 in pine-oak and montane riparian forests in southeastern Arizona. Bronzed and Brown-headed cowbirds partitioned hosts by host body size. Brown-headed Cowbirds did not parasitize larger hosts (i.e., Western Tanager, Piranga ludoviciana; and Hepatic Tanager, P. flava), while Bronzed Cowbirds did not parasitize smaller hosts (i.e., Painted Redstarts, Myioborus pictus; and Bell's Vireos, Vireo bellii). Although there was some host overlap (only 2/7 parasitized host species were parasitized by both cowbird species), only 3/48 nests (all Plumbeous Vireo, V. plumbeus) contained eggs of both parasite species. Parasitism by sympatric cowbirds in southeastern Arizona ...

RESPONSE OF BIRDS TO THINNING YOUNG DOUGLAS‐FIR FORESTS

Silvicultural practices, such as thinning, are increasingly performed both for commodity production and to help achieve biodiversity goals and promote ecological restoration. However, relatively little research has examined effects of thinning conifer forests on vertebrates. We experimentally manipulated stands using a randomized block design to evaluate influences of two thinning intensities on populations of diurnal breeding birds in western Oregon. We conducted point counts of birds seven times each year in 1994 (prior to treatment) and from 1995 through 2000 (subsequent to treatment). We analyzed data using multiple linear regression and information‐theoretic approaches to model selection. Of the 22 species for which we had sufficient data for analysis, detections of nine species decreased and eight species increased in thinned stands relative to controls, and there was no strong evidence that thinning influenced numbers of five species. Of the 17 species that responded to thinning, the magnitude of response of eight species varied with thinning intensity; for each of these species, response was greatest in the more heavily thinned stands. Although no species was extirpated from stands following thinning, detections of Hutton's Vireos (Vireo huttoni), Golden‐crowned Kinglets (Regulus satrapa), Brown Creepers (Certhia americana), Black‐throated Gray Warblers (Dendroica nigrescens), and Varied Thrushes (Ixoreus naevius) decreased to less than half of the detections in controls in one or more treatment types, suggesting thinning significantly reduces their numbers. In contrast, American Robins (Turdus migratorius), Townsend's Solitaires (Myadestes townsendi), and Hammond's Flycatchers (Empidonax hammondii) were rare or absent in controls but regularly present in thinned stands, and detections of Western Tanagers (Piranga ludoviciana), Evening Grosbeaks (Coccothraustes vespertinus), and Hairy Woodpeckers (Picoides villosus) increased by threefold or more in thinned stands relative to controls. Only Pacific‐slope Flycatchers (Empidonax difficilis), Warbling Vireos (Vireo gilvus), and Western Tanagers showed strong evidence of temporal trends in response. For these species, differences between numbers in controls and treated stands became more extreme through time. Our findings suggest that thinning densely stocked conifer stands in landscapes dominated by younger stands enhances habitat suitability for several species of birds, but that some unthinned patches and stands should be retained to provide refugia for species that are impacted by thinning.

A phylogenetic analysis of the emberizid sparrows based on three mitochondrial genes

Previous molecular phylogenetic studies have examined the taxonomic relationships among a number of typical emberizid sparrow genera. To help clarify these relationships, we sequenced a 1673 base pair fragment for the complete sequence of three mitochondrial genes: adenosine triphosphatase ( Atp8 and Atp6) and cytochrome oxidase subunit III (COIII) for 38 sparrow species, along with Passerina amoena (Cardinalidae) and Piranga ludoviciana (Thraupidae) which were selected as the outgroups. Our analysis confirms the monophyly of traditional genera such as Junco, Melospiza, and Zonotrichia. Although Calcarius and Plectrophenax are often thought to be putative emberizids, all our analyses placed these genera basal to all other sparrows examined. As observed with Calcarius, Spizella did not form a monophyletic group, with S. arborea being the sister-taxon to Passerella iliaca. Our analyses also suggest that Aimophila ruficeps is probably more closely related to the “brown towhees” ( Pipilo aberti, P. crissalis, and P. fuscus) than its putative congeners. The genus Ammodramus was also not monophyletic, since it appears that Passerculus sandwichensis is more closely related to A. henslowii and A. leconteii then either one is related to its congener A. savannarum. Finally, our analyses exhibited other unsuspected associations, such as the sister-taxon relationships between Amphispiza bilineata and the Chondestes grammacus/ Calamospiza melanocorys clade, and Amphispiza belli and Pooecetes gramineus.

Molt-Migration in Western Tanagers (Piranga Ludoviciana): Age Effects, Aerodynamics, and Conservation Implications

AbstractWe describe timing and location of the prebasic molt in Western Tanagers (Piranga ludoviciana), focusing on age class differences in premolt movements. Most adults migrate south to the American Southwest where they stop to molt before moving on to their wintering grounds. Molting adults are found in southern mountain regions (Sierra Madres and southern Rockies) and in the Mexican monsoon region, where late summer rains cause a substantial increase in productivity. In contrast, juvenile Western Tanagers move to nearby montane habitats to molt before migrating, a previously undocumented strategy in western passerines that show molt-related movements. By molting in nearby montane habitats, juveniles avoid the aerodynamic cost of migrating in their “fluffy”, aerodynamically inefficient juvenal plumage. Western Tanagers are the fifth species known to use the Mexican monsoon region during the prebasic molt, further affirming the importance of that area to the conservation of Neotropical migrants that breed in western North America.

MOLT-MIGRATION IN WESTERN TANAGERS (PIRANGA LUDOVICIANA): AGE EFFECTS, AERODYNAMICS, AND CONSERVATION IMPLICATIONS

We describe timing and location of the prebasic molt in Western Tanagers (Piranga ludoviciana), focusing on age class differences in premolt movements. Most adults migrate south to the American Southwest where they stop to molt before moving on to their wintering grounds. Molting adults are found in southern mountain regions (Sierra Madres and southern Rockies) and in the Mexican monsoon region, where late summer rains cause a substantial increase in productivity. In contrast, juvenile Western Tanagers move to nearby montane habitats to molt before migrating, a previously undocumented strategy in western passerines that show molt-related movements. By molting in nearby montane habitats, juveniles avoid the aerodynamic cost of migrating in their “fluffy”, aerodynamically inefficient juvenal plumage. Western Tanagers are the fifth species known to use the Mexican monsoon region during the prebasic molt, further affirming the importance of that area to the conservation of Neotropical migrants that breed in western North America.

HABITAT OF BIRDS IN PONDEROSA PINE AND ASPEN/BIRCH FOREST IN THE BLACK HILLS, SOUTH DAKOTA

Birds with both eastern and western distributions occur in the Black Hills of western South Dakota. This forest is mostly ponderosa pine (Pinus ponderosa) and is managed for timber. Logging alters forest characteristics and the bird community. We studied habitat relations of breeding songbirds at the stand- and site-level scales in ponderosa pine and quaking aspen (Populus tremuloides)/paper birch (Betula papyrifera) forest. Sixty bird species were observed ≤50 m from count points. Species richness was greater in aspen/birch than in ponderosa pine. Species richness was generally lower in ponderosa pine with >40% overstory canopy cover (OCC) than in ponderosa pine with ≤40% OCC and than aspen/birch of any structural stage. Seven bird species were associated with the ponderosa pine, while four species were associated with aspen/birch. Bird associations at the stand-level were further refined by OCC and diameter-at-breast-height (DBH) structural stage of each forest type. Habitats for most birds in the Black Hills can be managed using current forest inventory descriptions that include OCC and DBH. However, Red-naped Sapsuckers (Sphyrapicus nuchalis), Red-breasted Nuthatches (Sitta canadensis), White-breasted Nuthatches (S. carolinensis), Ovenbirds (Seiurus aurocapillus), and Western Tanagers (Piranga ludoviciana) were strongly associated with site-level vegetation characteristics. Snag density, snag condition, and deciduous trees beneath the ponderosa pine canopy should be included in forest inventories to better quantify habitats for these birds.