Monarch populations are not endangered – and EVEN IF the population declines, other butterfly species can fill in

What might be most surprising about the monarch butterfly, then, is that as a species, it is not actually endangered. The International Union for Conservation of Nature categorizes it a “species of least concern,” the designation reserved for those considered furthest from danger of extinction. A significant portion of this disconnect can be explained by the amount of press different segments of the global monarch butterfly population receive. Two distinct groups of migratory monarchs exist in North America: the aforementioned Mexican-Canadian population and a smaller population west of the Rockies that overwinters in California. It seems journalists simply can’t resist using these breathtaking, drama-filled migration spectacles for an attention-grabbing headline or lede (guilty!). So, as far as many people are aware, these are the only monarchs that exist—let’s call them the celebrity North American migrators. And it’s true: These populations, in Mexico and California, are on the downswing. The Western population in particular has been raising alarm bells, with some estimates putting the decimation as high as a 99 percent decline over the past few decades. After years of public pressure, our celebrity North American migratory subpopulations were listed as, yes, an endangered species in July. However, you’d be mistaken to think that monarchs are in dire need of our help—or remotely close to extinction. There are many, many more populations of monarchs. Danaus plexippus is also native throughout the rest of the Americas, with stable populations found in Florida, through the entirety of Central America and the Caribbean, and as far south as Venezuela. In the 1800s, likely as unintentional stowaways on trade ships, the insect colonized much of the tropical world. Today, the butterflies can also be found in abundance in Spain, Morocco, Hawaii, Australia, New Zealand, Indonesia, and much of the South Pacific; in these locales, they are a largely harmless, non-native, but still immensely successful species. Furthermore, there are two other species of monarch, which are also apparently stable in their numbers—Danaus erippus, which inhabits the southern half of South America, and Danaus cleophile, exclusive to the islands of Jamaica and Hispaniola. Even when it comes to the North American migratory subpopulations, the science is far from settled on just how urgent their peril is. Like many insect species, monarchs naturally have enormous population fluctuations from year to year. There’s no reliable data prior to 1993 on the North American monarch butterfly headcount. It’s possible that the years when reliable data collection started were anomalously abundant, and populations today have simply settled into more reasonable numbers.