Its Official: Monarch Butterflies are Endangered

Their populations have plummeted in recent years, but now the ICUN is officially recognizing their plight by listing them on its Red List as endangered.  According to counts in California and Mexico at the overwintering sites, the migratory insect's population has dropped by 95% since the 1980s. Danaus plexippus plexippus migrates in four generations over 4,000 miles from Canada to Mexico and California, one of the longest migrations in the Animal Kingdom.  It is beset with a host of threats from habitat loss to chemical poisoning and drought.

There are two populatins of Monarch butterflies in North America. The eastern population spends it winters in the coniferous forests of central Mexico. The western population lives in the Sierra Nevadas. The Mexican population is the most numerous and serves as a proxy for population counts. Its winter home is threatened by logging.  California's Monarch have increased in number recently up from a shocking 2,000 in 2020, an estimate undoubtedly affected by the pandemic. Still their numbers are well below the 1.2 million recorded in 1997.  They suffer from herbicide and pesticide overuse, and human development. In June of this year a California court ruled that invertebrates can be protected under the state's Endangered Species Act, opening the possibility of protecting their over-wintering sites.

The US Fish &Wildlife Service says Monarch qualify for listing as endangered under federal law, but priority is being given to other butterfly species.  According to a 2020 study the Service estimates that the Mexican population has a 50-70% chance of going extinct in sixty years. For the California population the chances are nearly certain of extinction in sixty years (99%). People are responding to the species plight by planting milkweed and other nectar bearing plants which they need for food and laying eggs. Reducing the use of pesticides and herbicides will also help them survive. There is hope for the Monarch, but time is running out. [photo credit: Xerces Society]