The writer is a professor of entomology specializing in insect conservation at the University of Hawaii.
One year ago, President Obama met with the leaders of Canada and Mexico. Their agenda included trade, security — and the conservation of the monarch butterfly.
Such high-level attention is nothing new to the monarchs, which are used to being treated like celebrities. White House meetings are convened to focus on saving them, senators demand their protection and a North American Monarch Conservation Plan has existed since 2008. A new high-level working group, charged with developing management plans to bolster the butterfly’s numbers, includes the heads of the Forest Service, National Park Service, Bureau of Land Management, Federal Highway Administration and Agriculture Department. Monarchs are an official insect of seven states, there are monarch festivals from California to Minnesota, and the monarch was the first butterfly to have its genome sequenced. We took them into space. The insect is even bred for release at weddings and funerals.
It’s enough to make a panda blush. But it has gone too far: A group of organizations and individuals has petitioned the Interior Department to protect the monarch by having it listed under the Endangered Species Act. I strongly support insect conservation and the organizations behind this effort, but I don’t support an endangered listing for the monarch.
It’s true that monarch populations in eastern North America are down about 90 percent in the past 20 years — a serious decline. Monarch watchers across the country report far fewer sightings than in the past. So why not list the species?
To begin, the overwintering population in Mexico still totals more than 30 million. Most insect conservationists would be thrilled to record numbers even a tenth of that for many rare species around the country. And that total doesn’t include the millions of monarchs in populations wintering in California, or those that live year-round in Central America and the Caribbean, or the introduced populations thriving across the Pacific islands and in Australia.
The monarch is one of the most widespread species of butterfly in the world. Its ability to find and colonize even isolated patches of milkweed — the host plant for their larvae — is renowned. Monarchs came to Hawaii more than 150 years ago, after milkweed was introduced, and they are now one of the most common and familiar insects in the state. They’ve moved through Tahiti, the Society Islands and New Caledonia. Once an occasional vagrant, the butterfly flourished after ornamental milkweed was brought to Guam and Australia. This is not a globally rare insect.
While the monarch is not an endangered species, the winter congregations of monarchs in Mexico are an “endangered phenomenon.” Their decline, thought initially to have been caused by the deforestation of the Oyamel firs they rely on for winter roosting, may have been accelerated by the increased use of genetically modified crops resistant to herbicides that are lethal to milkweed. But we are unlikely to lose even the migratory phenomenon; the gene governing their predilection for migrating is an ancient one, and we’d have trouble breeding the migration out of them if we tried. In fact, migratory overwintering by monarchs is not unique to North America. Introduced Australian and New Zealand monarchs migrate to the coast and gather en masse to ride out the austral winter. As long as there are monarchs in North America, they will migrate.
Unfortunately, species conservation can be very much a zero-sum game. Pouring additional resources into bolstering the monarch is sure to come at the expense of their less famous, less charismatic, but far rarer brethren. An endangered listing should be reserved for animals much closer to the brink, such as the Mariana wandering butterfly, which hasn’t been seen in more than 20 years. This species is known only from the Mariana Islands, where, incidentally, the monarch introduced itself and is thriving. Virtually nothing has been spent to protect the Mariana wanderer.
Even small amounts of additional money could help to save the already listed Mitchell’s satyr, a small butterfly that once occurred from the mid-Atlantic to the Midwest but is now restricted to a handful of fens in a fraction of its former range. The funding to help Appalachia’s spruce-fir moss spider or California’s Kern primrose sphinx moth (on which I work) is just a small slice of what has been committed to the monarch, yet these two species survive on postage stamps of remaining habitat. Perhaps the most egregious example is Hawaii’s fabulous green sphinx moth. It is the last of its kind — the only member of its genus — and fewer than 20 of these emerald beauties have ever been seen. Nothing is known about their natural history or vulnerability, and there are no plans to change that.
But this month the Fish and Wildlife Service dedicated $3.2 million just to grow more milkweed for the monarch. The millions in funding that the government is spending on the monarch (not counting the resources expended by the many private groups dedicated to the species) is money that is lost to the conservation of the unsung multitudes of rare insects that will never get their day in the sun, especially not now.
In an ideal world, the attention of three world leaders focused on a single species of declining butterfly would be a great sign of our maturation as a society, showing a real concern for biodiversity at all levels. But the reality suggests that limited resources are being lavished on a relatively secure species at the expense of large numbers of less well-known insects that are truly close to extinction. These critically threatened facets of nature’s diversity may not be as popular or flashy as the monarch, but losing them would be no less tragic.