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.
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.
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.
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
Links to information on species of frogs, toads, and salamanders located in the southeastern United States and the U.S. Virgin Islands, with information on appearance, habitats, calls, and status, plus photos, glossary, and provisional data.
We removed non-native fish from a section of the river and the endangered native species humpback chub increased in abundance. But it is not yet clear that decreased competition explains the rebound in population.