Geology Reports⌕ Search

USGS · 5210409

Buteos

Abstract

Red-tailed, red-shouldered, and broad-winged hawks nest throughout the 11 northeastern states, and red-tailed, red-shouldered, and rough-legged hawks winter in this region. Historical and present ranges of these species are similar, although red-shouldered and broad-winged hawk ranges now have more vacant patches at a local and regional level. Only the red-shouldered hawk is of special concern or officially listed as threatened by some state agencies. Analysis of Breeding Bird Survey (BBS) data indicated positive trends in counts of red-tailed hawks along the more developed Northeast corridor. No trends were found in analyses of BBS data for red-shouldered hawks in either more- or less-developed regions of the Northeast. Based on the BBS, we found a decreasing trend in counts of broad-winged hawks along the more-developed Northeast corridor, and an increasing trend in less-developed regions of the Northeast. Our analyses of Christmas Bird Count data indicated no trend in counts of red-shouldered nor rough-legged hawks, but an increase in counts of red-tailed hawks from 1962 to 1983. Many individuals believe that species such as the red-shouldered hawk are declining in the Northeast, but no trends were detected in our analyses.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

K. Titus, M.R. Fuller, D.F. Stauffer, J.R. Sauer. 1989. Buteos. https://pubs.usgs.gov/publication/5210409

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related USGS reports

Ground failure resulting from earthquake ground motions

The ground failure resulting from an earthquake, at all scales, is ultimately controlled by the details of near-surface earthquake ground motions, the spatially distributed mechanical characteristics of surface materials and how the two interact. This chapter introduces the aspects of ground-motion seismology that are most relevant to the triggering of different types of ground failure, such as landslides and liquefaction. In particular, the chapter focuses on different sources of local modification (e.g. amplification) of earthquake ground motions in the shallow subsurface, known as site effects. The chapter ends with an overview of the controls on, general spatial patterns of, and approaches to regional modelling of the manifestation of ground failure that may be triggered by an earthquake.

Book chapter↗

Loma salmonae and related species

Loma salmonae is a microsporidium that infects Pacific salmon and causes a gill inflammatory syndrome known as microsporidial gill disease of salmon. This disease has been mostly associated with netpen-farmed Chinook salmon ( Oncorhynchus tshawytscha ) in British Columbia, Canada. Clinical, diagnostic, pathological aspects of disease, as well as approaches for disease avoidance in salmon aquaculture are discussed. A laboratory infection model in rainbow trout was used to determine life cycle-stages, transmission dynamics, pathophysiology, influence of temperature, and to test therapeutics applicable to aquaculture. This experimental model has been informative on various approaches of disease control, including the development of a promising vaccine. In addition to improving fish health in salmon farming in North America, this L. salmonae model will be applicable to other microsporidial diseases that may be encountered in emerging aquaculture regions.

Book chapter↗

Cumulative effects of multiple stressors on marine mammals: Elephant seals as a model system

Noise exposure is a potential stressor for free-ranging marine mammals and is often studied in the absence of other environmental factors. Here, a multi-investigator, interdisciplinary effort was undertaken to examine the response of elephant seals to multiple stressors. An integrated physiological and ecological approach was taken, including immunology, stress physiology, toxicology, animal behavior, population biology, and life history theory, to examine the cumulative effects of exposure to multiple stressors in elephant seals. While we measured the response of individual animals, a population response can be predicted by incorporating these results into the long-term data on elephant seal demographics.

Book chapter↗