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Browse more than 160,000 publications authored by our scientists over the past 100+ year history of the USGS.  Publications available are: USGS-authored journal articles, series reports, book chapters, other government publications, and more.

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Economic effects assessment approaches: US National Parks approach

This chapter discusses the data and methods used by the US National Park Service to estimate the economic effects of National Park visitor spending to local and regional economies. Topics covered include a summary of economic effects analyses, required data for analysis (visitor count data, trip characteristics and spending patterns, and regional economic multipliers) and how these data are combin

Changes in seabed mining

Chapter 23 of the First World Ocean Assessment (WOA I) focused on marine mining, and particularly on established extractive industries, which are predominantly confined to near-shore areas, where shallow-water, near-shore aggregate and placer deposits, and somewhat deeper water phosphate deposits are found (United Nations, 2017a). At the time of publication, there were no commercially developed de

Golden Eagle

The Golden Eagle inhabits a wide range of latitudes and habitats throughout the Palearctic and into northern Africa, where it is largely resident. In North America, its breeding distribution includes most of Canada and Alaska, as well as the western half of the United States and northern and western Mexico. Most eagles that nest in northern Canada and interior and northern Alaska migrate thousands

Lake trout rehabilitation in Lake Ontario, 2020

Each year we report on the progress toward rehabilitation of the Lake Ontario lake trout (Salvelinus namaycush) population, including the results of stocking, annual assessment surveys, creel surveys, and evidence of natural reproduction observed from standard surveys performed by USGS and NYSDEC. Response to the COVID-19 pandemic limited survey effort such that spring and summer bottom trawl sur

GIS object data properties

Data properties are characteristics of GIS attribute systems and values whose design and format impacts analytical and computational processing.  Geospatial data are expressed at conceptual, logical, and physical levels of database abstraction intended to represent geographical information. The appropriate design of attribute systems and selection of properties should be logically consistent and s

Reduced quality and synchronous collapse of forage species disrupts trophic transfer during a prolonged marine heatwave

The Gulf of Alaska forage fish community includes a few key species that differ markedly in their timing of spawning, somatic growth and lipid storage, and in their migration behavior. This diversity in life history strategies facilitates resilience in marine food webs because it buffers predators against the naturally high variance in abundance of pelagic forage fish populations by decreasing the

Life history and population dynamics

Lake charr Salvelinus namaycush life history and population dynamics metrics were reviewed to evaluate populations inside (n = 462) and outside (n = 24) the native range. Our goals were to create a database of metrics useful for evaluating population status and to test for large-scale patterns between metrics and latitude and lake size. An average lake charr grew from a 69-mm length at age-0 (L0)

Trophic ecology

The trophic ecology of lake charr Salvelinus namaycush morphotypes from small and large lakes within their native and introduced ranges is reviewed over the past 50 years. The lake charr is an apex predator in most habitats it occupies, where it plays a significant role in defining food webs. While often considered piscivores, lake charr feed on a range of aquatic prey throughout their life histor


The lake charr Salvelinus namaycush is restricted in its native distribution to oligotrophic fresh waters of northern North America largely within the extent of the Pleistocene glaciations. It is the only freshwater species in northwest North America that does not occur in Siberia. A GIS-based native occurrence map linked to the HydroLAKES database does not extend the lake charr range but provides