Monarchs flying into an uncertain future
A flit of orange here, a dramatic butterfly alights over there - for many, the return of the monarchs to coastal California signals autumn, the turning of the seasons. But naturalists are wondering just how many will return this year. The world does not seem so safe for the monarch butterfly.
A few of us lucky enough to be there at the right time have marveled at the sight of a new butterfly emerging from a jade green chrysalis to fly freely. Lots of people make an annual pilgrimage to the monarch trees at Pacific Grove or Pismo Beach, Natural Bridges or Ardenwood, to be in awe over thousands of monarchs clustering together to make it through the winter. There is a committed group of volunteers who track the arrival of monarchs at protected coastal sites as part of a statewide effort to monitor long-term trends, advise land managers, and educate enthusiastic viewers.
What they witnessed last year was the lowest number ever of monarch butterflies at coastal overwintering roosts. It was also troubling that most overwintering sites outside the core area, from Santa Cruz to Santa Barbara, had few to no monarchs, and even in the core, numbers were just a fraction of those in earlier years. This year monitors already see early clues that the population continues to plummet. Few were seen at inland breeding sites this summer and early observations at key locations in Marin and Santa Cruz point to another sparse year. Results of the annual Thanksgiving Count, timed to check in on monarchs at the peak of their population, will be posted on the Xerces Society's web site as well as tips for viewing.
Scientists, park managers and the public are asking why. Could it be changing habitat? Is there a potential link to global climate change? How extensive is the loss of milkweed for caterpillars?
They also are trying to balance the monarch butterfly's proclivity for eucalyptus as a winter roost-tree with the fire hazard this tree species can pose, and efforts to control it on parkland. Conservationists lobby to ban the popular practice of releasing monarchs at events. Not only is this disrespectful of another life form, but it often confuses local scientific endeavors and usually results in the butterfly's mortality.
Fortunately, two of the biggest reasons monarchs are in trouble are also things interested people can do something about. The plant a monarch needs to find for its eggs is milkweed. There's very little of it left out in nature, but we each can plant it in our gardens, schoolyards, and public spaces. Monarch Watch offers special kits to enable the California gardener to re-establish a series of monarch "waystations" in the western breeding ranges.
Also we can all advocate healthy gardening and urge municipalities and our neighbors not to spray pesticides. In the coastal zone, urge local land managers to protect groves of trees where monarchs are known to roost for the winter and to manage these sites explicitly for monarchs.
Throughout North America there are many other efforts to protect monarchs. Students track the migration on Journey North. Tagging efforts help scientists learn about migration and population dynamics. Satellite imagery aids scientists' efforts to convince the Mexican government of the need for stricter protection from logging at the overwintering groves in Michoacan. Conservation organizations work with local villagers to replant trees and foster ecotourism.
Now's the time to watch out for monarchs, help make a world safe for them, and enjoy a visit to their overwintering world. Pause for a moment of awe to contemplate the wonders of metamorphosis, migration, and tenacity that keeps this fragile insect moving through the world we share.