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Book Chapters

Browse more than 5,500 book chapters authored by our scientists over the past 100+ year history of the USGS and refine search by topic, location, year, and advanced search.

Filter Total Items: 6158

Change-in-ratio Change-in-ratio

Change-in-ratio (CIR) methods are used to estimate parameters for ecological populations subject to differential removals from population subclasses. Subclasses can be defined according to criteria such as sex, age, or size of individuals. Removals are generally in the form of closely monitored sport or commercial harvests. Estimation is based on observed changes in subclass proportions...
Authors
Mark S. Udevitz

Change-in-ratio methods for estimating population size Change-in-ratio methods for estimating population size

Change-in-ratio (CIR) methods can provide an effective, low cost approach for estimating the size of wildlife populations. They rely on being able to observe changes in proportions of population subclasses that result from the removal of a known number of individuals from the population. These methods were first introduced in the 1940’s to estimate the size of populations with 2...
Authors
Mark S. Udevitz, Kenneth H. Pollock

Chemical regulation of spawning in the zebra mussel (Dreissena polymorpha) Chemical regulation of spawning in the zebra mussel (Dreissena polymorpha)

Previous literature suggests that spawning in bivalves is chemically regulated, both by environmental chemical cues and by internal chemical mediators. In a model proposed for zebra mussels, chemicals from phytoplankton initially trigger spawning, and chemicals associated with gametes provide further stimulus for spawning. The response to environmental chemicals is internally mediated by...
Authors
Jeffrey L. Ram, S. Jerrine Nichols

Comparison of neotropical migrant landbird populations wintering in tropical forest, isolated forest fragments, and agricultural habitats Comparison of neotropical migrant landbird populations wintering in tropical forest, isolated forest fragments, and agricultural habitats

Neotropical migrant bird populations were sampled at 76 sites in seven countries by using mist nets and point counts during a six-winter study. Populations in major agricultural habitats were compared with those in extensive forest and isolated forest fragments. Certain Neotropical migrants, such as the Northern Parula, American Redstart, and the Black-throated Blue, Magnolia, Black-and...
Authors
C.S. Robbins, B.A. Dowell, D.K. Dawson, J.A. Colon, R. Estrada, A. Sutton, R. Sutton, Dieter Weyer

Cortisol measurements in fish Cortisol measurements in fish

No abstract available
Authors
Z. Janey, G. Jeney, A.G. Maule

Dispersion in tidally averaged transport equation Dispersion in tidally averaged transport equation

A general governing inter-tidal transport equation for conservative solutes has been derived without invoking the weakly nonlinear approximation. The governing inter-tidal transport equation is a convection-dispersion equation in which the convective velocity is a mean Lagrangian residual current, and the inter-tidal dispersion coefficient is defined by a dispersion patch. When the...
Authors
R. T. Cheng, V. Casulli

Duck virus enteritis Duck virus enteritis

No abstract available.
Authors
D. E. Docherty, J. C. Franson
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