Canada Places Monarch Butterflies on Country’s Endangered Species List

A file photo of a monarch butterfly. (Danaus plexippus) on Dec. 19, 2016. Enrique Castro/AFP via Getty Images

Monarch butterflies, known for their distinctively-hued orange and black wings, have officially been listed as endangered under Canada’s Species at Risk Act (SARA).

Cabinet upgraded the status of monarch butterflies from special concern to endangered after Parliament received a Department of Environment report detailing the decline of one of the species’ key food sources: milkweed.

“This species is one of a few butterflies that migrate,” reads the report, which was first obtained by Blacklock’s Reporter. “Their migration from southern Canada to Mexico has been described as an endangered biological phenomenon.”

The “endangered” designation necessitates the development of a plan to save both monarch butterflies and the species’ habitat.

The endangered designation has been a long time coming. The Committee on the Status of Endangered Wildlife in Canada recommended the “endangered” listing back in 2016.

The committee, at the time, called the monarch a “showy species,” adding that it is “one of the most well-known butterflies in the world” at risk due to loss of habitat.

“Population size estimates are not available for Monarchs in Canada,” the committee wrote, adding that while monarchs were found in all provinces, “in some years the Western Canadian breeding population in British Columbia [was] so small as to be undetectable.”

Disappearing Habitat and Food Source

The U.S. Center for Biological Diversity in 2016 estimated that 165 million acres of monarch habitat had disappeared within two decades.

“This is a population that has been dropping like a stone,” professor Jeremy Kerr, conservation chair at the University of Ottawa, said in an interview at the time. “It’s close to the smallest numbers ever recorded. Their overall decline is probably 60 percent or more and it could be as high as 90 percent.”

An ongoing decline in milkweed is not only limiting the monarch’s habitat, but also its food source, according to Parks Canada.

Monarch caterpillars feed exclusively on the leaves of milkweed, a pink wildflower that could traditionally be found throughout North America. The Parks Canada website describes it as the only host plant for the species. Without milkweed, monarchs are unable to complete their life cycle, causing populations to decline.

The David Suzuki Foundation says pesticides have had a detrimental impact on monarch populations, particularly the “widespread use” of glyphosate, a “controversial herbicide” that has obliterated milkweed from much of the landscape.

“The two North American monarch populations [are] in a dire spot,” reads a 2022 blog post on the foundation’s website. “The western population, which overwinters in California, has declined by more than 95 per cent since the 1980s. The eastern population overwinters in Mexico and has declined by more than 70 per cent over the past three decades.”

The foundation criticized the Canadian government for “lengthy delays” in taking action despite the 2016 report about the impending extinction of the species.

Western Bumble Bee

Ottawa is also listing occidentalis bees, a subspecies of the western bumble bee, as “threatened” in British Columbia, Alberta, and Saskatchewan. The mckayi subspecies, meanwhile, has received a SARA designation as under special concern. This type of bee is found in B.C., Yukon, and the Northwest Territories.

Both species of bees are threatened by pesticide use, habitat change, and disease transmission from exotic bumble bee species, the government said in its SARA order summary.

“The occidentalis subspecies is threatened by intensive residential and commercial development in the lower mainland, lower Fraser Valley and greater Victoria area in British Columbia, as well as in Calgary and its surrounding area in Alberta,” the order reads. “Habitat loss from agriculture intensification is also a threat that is specific to the occidentalis subspecies.”

Receiving “endangered” and “threatened” designations under SARA means a species will be protected on all federal lands. It also requires the federal government to prepare recovery strategies in a bid to identify critical habitats and figure out what can be done to conserve the species.