No. 50: Mar-Apr 1987
Contrary to the report in SF#49, at least one tagged monarch butterfly has been found among the wintering colonies in Mexico. In early 1976, a tagged individual from Chaska, Minnesota, was indeed found among a huge cluster in Mexico. Also, a few butterflies tagged in the northern states have turned up in Texas, well on their way to Mexico.
(Urquhart, Fred A.; "Found at Last: The Monarch's Winter Home," National Geographic Magazine, August 1976. Cr. B. Ickes)
Comment. So, it seems that A.M. Wenner, the University of California researcher, will have to correct his records and perhaps modify his theory.