I grew up in Southern California, amidst orange groves (all gone now) and eucalyptus trees. There were always monarch butterflies around. Sometimes there were only a few. Other times, during their annual migration to and from South America, they would become dense. I remember biking through a eucalyptus grove on the UC San Diego campus and the monarchs were so thick that I got off my bike and walked to try to minimize the number that I would run over.
There are also lots of eucalyptus trees here on the island. Some Australian seedling salesman really got around. Unexpectedly, though, there are also monarch butterflies. What are they doing here, thousands of miles away from the migratory paths of monarchs in America? Unlike their American cousins, they don’t migrate thousands of miles along the west coast of the American continents, though apparently they do move from microclimate to microclimate.
—2p