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At least 937 records · Page 52Linked to original sources
USGS1991

[Book review] The known birds of North and Middle America: Distribution and variation, migrations, changes, hybrids, etc, Part I, Hirundinidae to Mimidae, Certhiidae

"Known Birds" is the culmination of Allan Phillips' long and productive career in elucidating the taxonomy and relationships of North American, particularly Mexican, birds. It reflects many years of largely independent work in the field, museum, and library. Although Part I includes contributions by Robert W. Dickerman, Amadeo M. Rea, and J. Dan Webster, the series (Part II will be available by the time this long-overdue review of Part I appears) reflects Phillips' views of avian systematics and his idiosyncratic scientific philosophy.

The Auk↗
USGS1992

Geographic Variation in Hirundo pyrrhonota (Cliff Swallow) from Northern North America

The number of subspecies recognized in Hirundo pyrrhonota Vieillot (Cliff Swallow) from Alaska, Canada, and the northern contiguous United States ranges from one (Peters 1960) to three (e.g., Jewett et al. 1953, Oberholser, 1920, breeding from central Alaska to the central Great Basin, and two disjunct populations of nominate pyrrhonota , breeding on the west coast and east of the Rocky Mountains. Although various authors have reported measurements of wing chord, they have not provided quantitative data for other plumage characters, and they disagree in the characterizations and ranges of the subspecies they recognize. Because of this, I reviewed the geographic variation among the northern populations. My study is confined to specimens from Alaska, Canada, and the contigeous United States south to Merced County in California, both slopes of the Rocky Mountains from Montana and Colorado, and northern half of the eastern United States from Kansas east to Virginia (Figure 1). The A.O.U. (1957) gave the breeding range of hypopolia as extending from Alaska and Mackenzie to southeastern British Columbia, the eastern parts of Washington, Oregon, and central-eastern California, central Nevada, northern Utah, Montana, and northwestern Wyoming, and the range of nominate pyrhonota as from southwestern British Columbia, western Oregon and Washington to southern California, southern Nevada, southern and eastern Utag, and east of the Rocky Mountains. I excluded specimens of H. p. ganieri Phillips, 1986, a subspecies (Browning 1990) that breeds from at least west-central Tennessee to Texas, and H. p. tachina Oberholser, 1903 (sensu Phillips 1986), which breeds north to central California, Utah, Arizona, and new Mexico. I follow Phillips (1973) for the use of the generic name Hirundo for the Cliff Swallow, Hellmayr (1935) for the use of the specific name pyrrhonota .

Western Birds↗
USGS2016

Assessing the seismic risk potential of South America

We present here a simplified approach to quantifying regional seismic risk. The seismic risk for a given region can be inferred in terms of average annual loss (AAL) that represents long-term value of earthquake losses in any one year caused from a long-term seismic hazard. The AAL are commonly measured in the form of earthquake shaking-induced deaths, direct economic impacts or indirect losses caused due to loss of functionality. In the context of South American subcontinent, the analysis makes use of readily available public data on seismicity, population exposure, and the hazard and vulnerability models for the region. The seismic hazard model was derived using available seismic catalogs, fault databases, and the hazard methodologies that are analogous to the U.S. Geological Survey’s national seismic hazard mapping process. The Prompt Assessment of Global Earthquakes for Response (PAGER) system’s direct empirical vulnerability functions in terms of fatality and economic impact were used for performing exposure and risk analyses. The broad findings presented and the risk maps produced herein are preliminary, yet they do offer important insights into the underlying zones of high and low seismic risks in the South American subcontinent. A more detailed analysis of risk may be warranted by engaging local experts, especially in some of the high risk zones identified through the present investigation.

Conference Paper↗