Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock () or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Ed Pfeifer of the USGS Southwest Geographic Science Team surveying alpine vegetation during a field study of Dall sheep habitat in Denali National Park, Alaska, on July 28, 2009.
Public Domain.
