Sorry for the pessimistic headline, but this item is just plain gloomy. The already-precipitous decline of migratory monarch butterflies just got worse.
As reported this past week by the New York Times, the most current measurement of the migratory population has plummeted:
The migrating population has become so small — perhaps 35 million, experts guess — that the prospects of its rebounding to levels seen even five years ago are diminishing. At worst, scientists said, a migration widely called one of the world’s great natural spectacles is in danger of effectively vanishing.
The Mexican government and the World Wildlife Fund said at a news conference on Wednesday that the span of forest inhabited by the overwintering monarchs shrank last month to a bare 1.65 acres — the equivalent of about one and a quarter football fields. Not only was that a record low, but it was just 56 percent of last year’s total, which was itself a record low.
At their peak in 1996, the monarchs occupied nearly 45 acres of forest.
The decline is generally blamed on changes in land use that reduce available habitat and food supply along migratory routes. But recent weather swings have also been a factor. Here’s more from the World Wildlife Federation’s Mexico office. (Note: That article is in Spanish, but my browser offered an English translation that seems fairly accurate.)
This discussion is about the migration of monarchs that move from Mexico to North America each year. While beautiful and massive, it’s not the whole population. National Geographic put it this way:
Though monarchs are found in many parts of the world, the migratory monarch is the most thoroughly studied, since it’s the group that’s most at risk. (Watch a video of monarch butterflies.)
Omar Vidal, director general of WWF-Mexico, noted by email: “The monarch butterfly as a species is not endangered. What is endangered is its migratory phenomenon from Canada to Mexico and back.”
Even if monarchs may hang on in non-migratory locations, this big-picture, overall trend seems discouraging. This Christian Science Monitor article offers up a glimmer of hope through activism, saying “Teachers, schoolchildren, brides, and others have begun fighting back, one seed at a time” by planting milkweed and other plants butterflies need.
The Internet offers a fair number of useful informational or advocacy sites devoted to this topic, such as the Monarch Butterfly Fund. A leading expert on monarchs, Dr. Karen Oberhauser, called the recent news out of Mexico “terrible”. While deeply saddened, she added this call to action:
…as a conservation biologist, I know that what is happening to monarchs is also happening to many other uncounted organisms – organisms whose loss would be equally tragic. We know about monarchs because they gather in discrete locations every winter, and because thousands of volunteers count them as part of over a dozen different monarch and butterfly citizen science programs. Monarchs can serve as both indicators of what is happening to many other insects, and as an impetus to save the habitat that they and these uncounted insects require. To preserve the monarch migration, we need a groundswell of conservation engagement, similar to that experienced in this country during the 1960’s and 70s when we passed important environmental legislation that resulted in protection for endangered species, as well as the water we drink, and the air we breathe.