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[EN]: From surveys in many countries, we report raptors using unusual nesting materials (e.g., paper money, rags, metal, antlers, and large bones) and unusual nesting situations. For example, we documented nests of Steppe Eagles [Aquila nipalensis] and Upland Buzzards [Buteo hemilasius] on the ground beside well-traveled roads, Saker Falcon [Falco cherrug] eyries in attics and a cistern, and Osprey [Pandion haliaetus] nests on the masts of boats and on a suspended automobile. Other records include a Golden Eagle [A. chrysaetos] nest 7.0 m in height, believed to be the tallest nest ever described, and, for the same species, we report nesting in rudimentary nests. Some nest sites are within a few meters of known predators or competitors. These unusual observations may be important in revealing the plasticity of a species' behavioral repertoire., [ES]: A partir de censos realizados en muchos países, documentamos el uso de materiales inusuales (e.g., billetes, trapos, metal, cuernos de ciervos y huesos grandes) para la construcción de los nidos y de situaciones de anidación inusuales por parte de las rapaces. Por ejemplo, documentamos nidos de Aquila nipalensis y de Buteo hemilasius en el suelo al lado de caminos muy transitados, de Falco cherrug en áticos y en una cisterna, y de Pandion haliaetus en los mástiles de barcos y en un automóvil suspendido. Otros registros incluyen nidos de A. chrysaetos a 7.0 m de altura, lo que se cree es el registro más alto descrito hasta la fecha y, para la misma especie, documentamos anidación en nidos rudimentarios. Algunos sitios de anidación están a pocos metros de depredadores o competidores conocidos. Estas observaciones inusuales pueden ser importantes en revelar la plasticidad del repertorio de comportamientos de la especie., Publication costs were paid by NASA-Goddard Space Flight Center, U.S. Geological Survey Forest and Rangeland Ecosystem Science Center, U.S. Geological Survey Southwest Biological Research Center, and Bureau of Land Management, Central Yukon Field Office.

A breeding population of red—shouldered hawks (Buteo lineatus) along the Patuxent River in central Maryland was studied during the interval 1943—71. Numbers of breeding pairs remained unchanged or increased on the PWRC (Patuxent Wildlife Research Center) and an adjoining area where habibat was not altered. A reduction in breeding pairs occurred on the third study area where large portions of the habitat had been destroyed. Basic information on 74 nests was obtained and the annual number of breeding pairs on the PWRC ranged from a low of four to a high of nine during the study. Nesting success of this highly territorial species decreased significantly as the distance between adjacent nest sites decreased (Errington's principle of inversity). Since 1960, the recruitment rate during high density years was 1.34 young fledged per pair as opposed to 1.95 during optimum (1943 and 1947 levels) density years. The 1.95 figure compared favorably with the estimated recruitment rate necessary for maintaining a stable ...

Gizzards of 934 sora rails (Porzana carolina) collected in Maryland (767) and Missouri (167) were examined for ingested shot. Ingested shot were found in 12.3 percent of the Maryland sample and 1.8 percent of the Missouri birds. Individual Maryland birds had ingested up to 28 pellets. None of the lead pellets examined was larger than a No. 71/ shot. Maryland ingestion rates did not differ by age or sex, but significant differences between collection areas, groups of years, and collection periods within years were indicated. This exploratory work points out a potential lead poisoning prob- lem among sora rails. J. WILDL. MANAGE. 39(3):514-519 Although the incidence of ingested lead shot and knowledge of its adverse effects have been well documented for many Anat- idae, most non-waterfowl reports are based on small samples, and evidence of the effects of lead shot is largely circumstantial.