When Monarch butterflies come up in conversation, we usually think of the 3,000-mile journey they make between Canada and Mexico east of the Rockies. These Monarchs return each winter to roosts in the hills of Michoacan, Mexico, where they gather by the millions. What people often do not realize is that over a million Monarchs also make a western migration. Monarchs west of the continental divide overwinter along the coast of California and breed on milkweed as far north as British Columbia. Although the winter roosts are not as large as their Mexican counterparts, these magical places may contain tens of thousands of gorgeous butterflies. In fact, many of these West Coast sites are open to the public.

Sadly, many of these sites are threatened by development and loss of the trees that create the unique conditions required by these resting butterflies. The Xerces Society, in cooperation with other conservation groups in California, is reinvigorating our effort to protect these sites and offer expertise regarding their management.

For more information please visit the pages in this website....

Monarchs that survive the winter are more than six months old, with tattered wings and colors that are fading with age, like in this photo taken in late January, 2004 in Pacific Grove, California. Photo by Mace Vaughan