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Milpitas, CA, United States

Carmi O.,San Francisco State University | Carmi O.,California Academy of Sciences | Witt C.C.,University of New Mexico | Jaramillo A.,San Francisco Bay Bird Observatory | And 2 more authors.
Molecular Phylogenetics and Evolution | Year: 2016

The Vermilion Flycatcher (Pyrocephalus rubinus) is a widespread species found in North and South America and the Galápagos. Its 12 recognized subspecies vary in degree of geographic isolation, phenotypic distinctness, and migratory status. Some authors suggest that Galápagos subspecies nanus and dubius constitute one or more separate species. Observational reports of distinct differences in song also suggest separate species status for the austral migrant subspecies rubinus. To evaluate geographical patterns of diversification and taxonomic limits within this species complex, we carried out a molecular phylogenetic analysis encompassing 10 subspecies and three outgroup taxa using mitochondrial (ND2, Cyt b) and nuclear loci (ODC introns 6 through 7, FGB intron 5). We used samples of preserved tissues from museum collections as well as toe pad samples from museum skins. Galápagos and continental clades were recovered as sister groups, with initial divergence at ~1 mya. Within the continental clade, North and South American populations were sister groups. Three geographically distinct clades were recovered within South America. We detected no genetic differences between two broadly intergrading North American subspecies, mexicanus and flammeus, suggesting they should not be recognized as separate taxa. Four western South American subspecies were also indistinguishable on the basis of loci that we sampled, but occur in a region with patchy habitat, and may represent recently isolated populations. The austral migrant subspecies, rubinus, comprised a monophyletic mitochondrial clade and had many unique nuclear DNA alleles. In combination with its distinct song, exclusive song recognition behavior, different phenology, and an isolated breeding range, our data suggests that this taxon represents a separate species from other continental populations. Mitochondrial and nuclear genetic data, morphology, and behavior suggest that Galápagos forms should be elevated to two full species corresponding to the two currently recognized subspecies, nanus and dubius. The population of dubius is presumed to be extinct, and thus would represent the first documented extinction of a Galápagos-endemic bird species. Two strongly supported mitochondrial clades divide Galápagos subspecies nanus in a geographic pattern that conflicts with previous hypotheses that were based on plumage color. Several populations of nanus have recently become extinct or are in serious decline. Urgent conservation measures should seek to preserve the deep mitochondrial DNA diversity within nanus, and further work should explore whether additional forms should be recognized within nanus. Ancestral states analysis based on our phylogeny revealed that the most recent common ancestor of extant Vermilion Flycatcher populations was migratory, and that migratory behavior was lost more often than gained within Pyrocephalus and close relatives, as has been shown to be the case within Tyrannidae as a whole. © 2016 Elsevier Inc. Source

Raimilla V.,University of Los Lagos | Hauenstein E.,Catholic University of Temuco | Norambuena H.V.,Programa de Conservacion de Aves Rapaces y Control Biologico | Jaramillo A.,San Francisco Bay Bird Observatory
Ornitologia Neotropical | Year: 2012

The Hellmayr's Pipit (Anthus hellmayri) is a poorly known species distributed through southern South America. It is represented by three subspecies; one of them, A. h. dabbenei, is considered migratory. Although it is believed that A. h. dabbenei is migratory in Chile, there is insufficient evidence to its status. In the period between 2010 and 2011 we conducted an exhaustive search for this species in the Araucania Region of south-central Chile. In addition, historical and previous records by the authors were included in the analysis. In total, we recorded 57 individuals from sea level to 1400 m a.s.l., found in the period between September and March in the years 2003-2011. These findings support what appears to be regular migratory behavior of a summer resident species in Chile, not a vagrant as suggested by previous works. The habitats used in Chile are similar to those reported in Argentina and Uruguay, and can be categorized as grasslands dominated by annual plants, and with the presence of isolated shrubs. We also discuss reproduction and seasonality of Hellmayr's Pipit in Chile. © The Neotropical Ornithological Society. Source

Goodman R.E.,San Francisco State University | Lebuhn G.,San Francisco State University | Seavy N.E.,PRBO Conservation Science | Gardali T.,PRBO Conservation Science | Bluso-Demers J.D.,San Francisco Bay Bird Observatory
Global Change Biology | Year: 2012

There has been a growing interest in whether established ecogeographical patterns, such as Bergmann's rule, explain changes in animal morphology related to climate change. Bergmann's rule has often been used to predict that body size will decrease as the climate warms, but the predictions about how body size will change are critically dependent on the mechanistic explanation behind the rule. To investigate change in avian body size in western North America, we used two long-term banding data sets from central California, USA; the data spanned 40 years (1971-2010) at one site and 27 years (1983-2009) at the other. We found that wing length of birds captured at both sites has been steadily increasing at a rate of 0.024-0.084% per year. Although changes in body mass were not always significant, when they were, the trend was positive and the magnitudes of significant trends were similar to those for wing length (0.040-0.112% per year). There was no clear difference between the rates of change of long-distance vs. short-distance migrants or between birds that bred locally compared to those that bred to the north of the sites. Previous studies from other regions of the world have documented decreases in avian body size and have used Bergmann's rule and increases in mean temperature to explain these shifts. Because our results do not support this pattern, we propose that rather than responding to increasing mean temperatures, avian body size in central California may be influenced by changing climatic variability or changes in primary productivity. More information on regional variation in the rates of avian body size change will be needed to test these hypotheses. © 2011 Blackwell Publishing Ltd. Source

Spotswood E.N.,University of California at Berkeley | Goodman K.R.,University of California at Berkeley | Carlisle J.,Boise State University | Cormier R.L.,PRBO Conservation Science | And 4 more authors.
Methods in Ecology and Evolution | Year: 2012

The capture of birds using mist nets is a widely utilized technique for monitoring avian populations. While the method is assumed to be safe, very few studies have addressed how frequently injuries and mortalities occur and the associated risks have not been formally evaluated. We quantified the rates of mortality and injury at 22 banding organizations in the United States and Canada and used capture data from five organizations to determine what kinds of incidents occur most frequently. Analyses focused on passerines and near-passerines, but other groups were included. We evaluated whether body mass, age, sex, mist net mesh size, month and time of day or frequency of capture are related to the risk or type of incident. We also compared the recapture histories over time between birds that were injured and those that were never injured for 16 species. The average rate of injury was 0·59%, while mortality was 0·23%. Birds captured frequently were less at risk to incident. Body mass was positively correlated with incident and larger birds were at greater risk to predation, leg injuries, broken legs, internal bleeding and cuts, while smaller birds were more prone to stress, tangling-related injuries and wing strain. Rates of incident varied among species, with some at greater risk than others. We found no evidence for increased mortality over time of injured birds compared with uninjured birds. We provide the first comprehensive evaluation of the risks associated with mist netting. Our results indicate that (1) injury and mortality rates below one percent can be achieved during mist netting and (2) injured birds are likely to survive in comparable numbers to uninjured birds after release. While overall risks are low, this study identified vulnerable species and traits that may increase a bird's susceptibility to incident that should be considered in banding protocols aimed at minimizing injury and mortality. Projects using mist nets should monitor their performance and compare their results to those of other organizations. © 2011 The Authors. Methods in Ecology and Evolution © 2011 British Ecological Society. Source

Harrison P.,Swingates | Sallaberry M.,University of Chile | Gaskin C.P.,400 Leigh Road | Baird K.A.,Forest and Bird | And 9 more authors.
Auk | Year: 2013

We describe a new species of storm-petrel, Oceanites pincoyae (Pincoya Storm-Petrel), from the Puerto Montt and Chacao channel area, Chile. The description is based on 1 specimen collected at sea in Seno Reloncavi on 19 February 2011 and 11 other individuals that were caught, examined, and released. The new taxon's foraging ecology and behavioral habits are unique among the southern Oceanitinae, including "mouse-runs" and repeated diving beneath the surface to retrieve food items. Its distinctive appearance includes bold white ulnar bars, extensive white panels to the underwing, and white to the lower belly and vent. Among species of Oceanites, it is unique in showing white outer vanes to the outer two pairs of rectrices. It further differs from all other storm-petrels in having a distinctive juvenile plumage. Morphometrically it is distinct from Oceanites gracilis gracilis (Elliot's Storm-Petrel) and smaller than O. oceananicus chilensis (the Fuegian form of Wilson's Storm-Petrel), having a shorter tarsus and longer middle toe. There also appear to be differences in the timing of breeding and molt between the new taxon and both O. o. chilensis and O. g. gracilis. We estimate the population size of the new species as ~3,000 individuals. Copyright © 2013 by The American Ornithologists' Union. Source

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