Milkweed and Monarch Butterflies

This week, the University of Guelph, Ontario published a study on the relationship between the reduction in milkweed plants and the decline of monarch butterflies. See news story "Habitat Loss on Breeding Grounds Cause of Monarch Decline" . The full text of the article is available for purchase through the Journal of American Ecology. Although the loss of wintering breeding grounds in Mexico is certainly one factor impacting their survival, this article suggests that more resources should be spent on restoration of milkweed habitat. Monarch caterpillars only feed on milkweed plants which sustain the larvae and help protect monarch's from predators.  The toxins from the plant that are consumed by the caterpillar carry over to the adult and cause predators to avoid them. The study concludes that since 1995 there has been a 21 percent decline in milkweed due to the expansion of industrial agricultural and the growing of genetically modified crops that allow for the wide-spread use of herbicides that kills all weeds.There are several efforts underway to help monarchs survive. MonarchWatch.Org has a Bring Back the Monarchs campaign which focuses on restoring monarch habitat by propagating 20 species of milkweed which are host plants for monarchs across the country.

 
This is another plant that I remember being in abundance when I was a child. My mother would sometimes collect the pods in the fall and and spray-paint them for dried flower arrangements. In the past few years, milkweed plants have been popping up all over the yard and sometimes in the garden. We try and leave them when possible, but I have yet to see a monarch caterpillar on any. There have been on occasion however, the larvae of the milkweed tussock moth - not nearly as exciting. We seem to have more milkweed than ever this year, so maybe we will be lucky and one monarch will decide to stop by and continue her life cycle. If you are interested in tracking or reporting sightings of monarchs check out the Journey North website.