Status, Distribution & Conservation

The Monarch Butterfly, Danaus plexippus L., in Canada

International Cooperation and Canadian Conservation Efforts

The Monarch butterfly is the only current example of what has come to be known as an "endangered phenomenon" (Wells et al. 1993; Pyle 1983; Brower & Malcolm 1989; Malcolm 1993). The scope of the migration undertaken by this species - where the return trip to the overwintering roosts is accomplished by butterflies that are five generations removed from those that made the re-colonization trip north the preceding spring (akin to a person having to find the origin of their great-great-great grandparent with no intergenerational information transfer!) - is truly a phenomenon. Brower (1995) fears that the phenomenon of the migration of the Monarch could become extirpated in North America in less than 20 years if nothing is done now. Canada is, in my opinion, the ultimate source of probably 25 to 35% of the eastern migrants which overwinter in Mexico each year, thus, conservation efforts here may have a large impact on recruitment to the overwintering roosts. Recruitment to the overwintering roosts in turn affects the numbers of spring migrants that return to Canada.

Unilateral conservation efforts by Canada will, however, be ineffective in conserving this endangered phenomenon - a concerted international effort is required. Absolute protection of the overwintering sites in Mexico and California is necessary, as are efforts to protect breeding and migratory habitats throughout the United States and Canada. Mexico especially should be encouraged to promote non-consumptive use of the eastern overwintering sites, for example through "controlled" tourism at only one or two of the sites and effective protection of all other roosts. In California, the loss of roosts to urban development must be halted immediately. Throughout the United States and Canada efforts to promote the breeding success of Monarchs, particularly through cessation of wide-scale herbicide/pesticide programs, should be encouraged. Similarly, efforts to protect significant staging areas used in migration should be continued. In all three nations, concerted education efforts - such as the various Monarch programs (Brower & Walton 1996; Hyslop 1996)) already in place and the Canadian Museum of Natures "Butterfly Beyond Borders" travelling exhibit (Hyslop 1996) - should continue and, if possible, be expanded upon.