Main page for accessing links for information and data on the San Francisco Bay estuary and its watershed with links to highlights, water, biology, wetlands, hazards, digital maps, geologic mapping, winds, bathymetry and overview of the Bay.
Doppler radar imaging is used for tracking the migration and behavior of bird populations. With the U.S. Fish and Wildlife Service and other agencies, USGS uses this technology to assist decision makers balance natural and industrial concerns
Clearinghouse for the description and availability of multiple geospatial datasets relating to Alaska from many federal, state and local cooperating agencies under the coordination of the Alaska Geographic Data Committee.
Links to volcanism, volcanic history, volcanic rocks, and general geology by state, by region, national parks and national monuments and a brief introduction to volcanism around the U.S. entitled: Windows into the past.
Homepage for the Dept. of the Interior's Initiative coordinated by the USGS, for amphibian (frogs, toads, salamanders and newts) monitoring, research, and conservation. Links to National Atlas for Amphibian Distribution, photos, and interactive map serve
They're abundant in this area, but hard to count reliably. We outline a procedure for estimating the population sizes so that we can determine whether they're increasing or dwindling. We must both listen for their calls and visually confirm them.