Estimates of monarch butterfly mortality from last week's storm are premature. Those who benefit from butterfly tourism downplay the damage. Yet the destruction caused by the unseasonal dumping of ice and snow may be less than we thought at first. Warmer weather over the weekend melted the thin ice cover on Cerro Pelon, and we saw many butterflies thawing out and taking flight. Nearby nectar sources were killed by the freeze. The remaining monarchs are definitely on the move; we're seeing migrators everywhere, all over Macheros, the valley village where we live, as well as the busy streets of nearby Zitacuaro.
Discussions of the storm so far have centered on the impact of ice and freezing temperatures on the colonies. Less mention is made of the loss of tree cover during the violent windstorm that accompanied the snow and sleet in the early morning of March 9th. At least 50 trees were ripped out by their roots in the roost above El Llano de Tres Gobernadores. CEPANAF forest ranger Patricio Moreno estimates that at least 200-250 trees were toppled throughout Cerro Pelon's protected area. Spots on the mountain that were once submerged in deep mossy shade are now exposed to sunlight. The landscape was so transformed that I had trouble recognizing places I'd visited almost every week this season. My husband Joel and I both came home with sunburns on March 11, the first time all season.
I fear that the long-term effects of this extreme weather event on the microclimate of the Biosphere Reserve may well put the migration in even more peril than the much debated mortality rate. If there is one take away message from this tragedy, it's that taking action to confront climate change cannot wait.
Ellen Sharp
Co-owner, JM Butterfly B&B
Macheros, Estado de Mexico