Where are the Monarchs?

Sat, 09/21/2013 - 2:00pm

The date of Sept. 15 was as likely as not to be the peak of goldenrod blooms on Block Island. Whether it is a glowing field of gold or the subtle elegance of a stonewall edged by yellow, mid-September is a time of stunning beauty. Just when you think that a summer-browned field cannot become more illuminated by the transition of hay to goldenrod, you notice an orange fluttering among the stems and realize that the gold-leafed field is glittering with Monarch butterflies... but not this year.

Every year I feed, tend, shepherd and support the growth of about five to 10 Monarch caterpillars. September is filled with peeking under milkweed leaves for Monarch eggs and caterpillars and, usually, collecting milkweed leaves to feed the hungry larvae on their way to chrysalis and butterfly… but not this year.

On that date, Sept. 15, I saw a Monarch butterfly. A single Monarch butterfly floating on the sunny Sunday afternoon. All I could think was “please let this one migrate successfully to Mexico.”

As many of you know, Monarchs have an amazing migration pattern. In the fall Monarch butterflies east of the Rocky mountains migrate to a small area in the mountain forests of Mexico where they will overwinter. (Monarchs from west of the Rocky Mountains overwinter in a small area of California mountains.)

In March, with warming temperatures and longer days, the butterflies start migrating north again. First they go to the southern-tier U.S. states where they will mate; leaving successive generations to follow the milkweed-growing season northward, as far as southern Canada by summer’s end. Then once again, a new set of adults (4 to 6 generations beyond the previous year’s migrants) will head back to Mexico for the winter.

Alas, Monarch butterflies and their miraculous migration are endangered. Such a small and fragile creature with such an unlikely migration is, at best, subject to population swings based on normal yearly fluctuations of weather. Such fluctuations may inhibit or support successful winter hibernation, the rearing of future generations, and the growth of the Monarch’s main food source, milkweeds, throughout its range. There are many species in this group. Unfortunately, the Monarch butterfly species is not facing “normal” fluctuations of weather.

Unusually cold winters with snow in Mexico can reduce the Monarchs overwintering population. However, the problems more recently have been unusually warm springs that cue the butterflies to mate and lay eggs that hatch ahead of the growth of milkweeds. These springs have been followed by hotter-than-usual summers that inhibit optimal egg laying and desiccate eggs before they can hatch.

There are two other factors affecting the Monarch butterfly species: loss of habitats supporting milkweed growth, and the huge expansion of corn and soybean crops that use herbicide-tolerant, genetically-modified seed throughout the Monarch’s breeding range. The use of these seeds allow for the use of herbicides on large swaths of land where milkweeds were once abundant in the natural landscape and between crop rows. With huge reductions in habitat and food sources the Monarch population has also hugely been reduced.

In the 2012/13 winter (following a very hot summer and an increase of 25 million acres of corn and soybean crops between 2006 and 2012) the overwintering population of Monarch butterflies in Mexico covered about three acres; this was the lowest amount ever recorded and represented a 59 percent decrease from the previous year. This represents less than 100 million butterflies (sounds like a lot, but is not) and essentially is the “base stock” for 2013. Unfortunately, both spring and summer 2013 weather conditions in much of the Monarchs’ breeding and feeding range was less than optimal for a “normal” year of recruitment — and certainly was not what was needed for rebuilding the diminished population.

And so, it has not been a good year for Monarch butterflies. Dr. Chip Taylor, butterfly conservationist and Director of Monarch Watch out of the University of Kansas, has predicted that the upcoming overwintering population in Mexico will be even smaller than last year’s. Yet, Dr. Taylor is hopeful. Through education, the planting of milkweeds, and the establishment of Monarch-friendly habitats, each of us can be part of the solution. We must do what we can for the care and feeding of Monarchs — and this includes objecting to “mono crops” that limit naturally occurring hedgerows and butterfly- and insect-friendly habitats; as well as reducing the broad-based use of herbicides that suppress beneficial herbs and weeds as “collateral damage” in our quest for cheap sweeteners, fuels and livestock grains.

To learn more about Monarch butterflies check out these resources that were used in the creation of this article: MonarchWatch.org; “Four Wings and a Prayer” by Sue Halpern

For more opportunities to search out a rare 2013 glimpse of Monarch butterflies and to enjoy other September sights, join these Ocean View Foundation events and programs:

Sept. 21 from 9 a.m. to noon: International Coastal Cleanup, meet at the Town Beach.

Sept. 22 at 4:44 p.m.: Autumnal Equinox

Sept 25 at 5 p.m.: Bird Walk at Andy’s Way

Sept. 27 at 7:30 p.m.: Night SkyViewing, at the Hodge Preserve, Corn Neck Rd.

Sept. 28 at 7 p.m.: at the Island Free Library: The Revenge of the Electric Car (film) at the Island Free Library.

Sept. 31 (a.k.a. Oct. 1) at 8 a.m.: Crazy-as-a-Coot Bird Walk