Monarch butterflies can use all the help they can get
While mowing last week, I noticed that the first sprouts of milkweed plants were starting to poke their heads skyward in my annual “patch,” a sure harbinger that the heralded and stressed monarch butterflies must be headed north.
As you read this, second-generation monarchs likely are moving north through Ohio and similar latitudes east of the Rockies from their wintering grounds in the oyamel fir forests in the mountains a couple hours west of Mexico City. A separate, smaller population winters west of the Rockies at Pacific Grove, Calif.
Though not the only insects to migrate – some dragonflies and moths also do, for instance – the monarch story is by far the most dramatic, especially because of the long stances involved. I once recall watching monarchs fluttering from wildflower to wildflower, feeding on nectar, during a bass fishing trip on the Madawaska River at Combermere, Ontario, hours north of Toronto. That is a whopping 2,750 miles from the species’ winter home in north-central Mexico.
One theory has it that the familiar, big, orange-and-black butterflies evolved their migratory habits by following the retreating ice sheets at the end of the last Ice Age.
The migration entered six new states and the first Canadian province as of mid-month. Watch for sightings to surge as the population swells in late May and expands into most of the breeding range.
Monarch populations have been in a long-term tailspin, down some 90 percent, for more than 20 years because of timbering and pine-bark beetle infestations in the mountain fir forests in Mexico, increasing frequency of severe weather events linked to rapid climate change, and conversion of 2.2 million more acres of potential milkweed habitat to industrial agriculture and other development. Increasing use of herbicides such as Roundup also has had a serious impact.
However, a national initiative to conserve monarchs, joined here in Ohio, is under way. Individuals can start pollinator gardens now, including some native wildflowers. Check local nurseries and garden stores for plants like common milkweed, swamp milkweed, and purple coneflower.
Every pollinator garden helps. So does noticing emergent patches of milkweed and just letting them grow, avoiding the relentless urge to mow, mow, mow some mo’. The latter advice also would be well-heeded by township, county, and state road crews, which invariably waste thousands of taxpayer dollars by needlessly mowing highway roadsides, thus wrecking both monarch habitat and all sorts of ground-nesting wildlife and bird habitat for no good reason. (Some selective mowing for reasonable highway-safety, yes; scorched-earth scalping, as usually practiced, no. It is just plain ignorant.)
For a fascinating, interactive map showing monarch migration click here. The same online site also offers an excellent educational slide show to help distinguish monarchs from three other look-alikes – the viceroy, the queen, and the painted lady butterflies.