Core distribution of <a href="//commons.wikimedia.org/w/index.php?title=Bull_trout&amp;action=edit&amp;redlink=1" class="new" title="Bull trout (page does not exist)">bull trout</a> (<i>Salvelinus confluentus</i>) in United States lower 48 states from the 5 year Reivew U.S. Fish and Wildlife Service.  2005.  Bull Trout Core Area Conservation Status Assessment. U.S. Fish and Wildlife Service, Portland, Oregon.
US Fish and Wildlife Service
<a rel="nofollow" class="external free" href="https://www.fws.gov/pacific/bulltrout/Maps/MapCs.pdf">http://www.fws.gov/pacific/bulltrout/Maps/MapCs.pdf</a>