Number of Monarch Butterflies Released Annually Closer to 32,000 than “millions and millions” as Claimed by Endangered Species Act Petitioners

The iconic monarch butterfly is a popular choice for releases. Efforts to grant it threatened status are grossly overstating the estimated numbers released by the butterfly industry. (Photo: Business Wire)

MIAMI--()--The International Butterfly Breeders’ Association (IBBA), which represents 104 members around the world, took issue with inaccurate claims made by petitioners hoping to achieve “threatened” status for the iconic Monarch butterfly (Danaus plexippus plexippus) under the Endangered Species Act.

On August 26, 2014, several groups (Xerces Society, Center for Food Safety, Center for Biological Diversity and Dr. Lincoln Brower) submitted a petition to the Secretary of the Interior that suggested “at least a few million monarchs are released into the wild annually.” In fact, the number of Monarchs released by commercial butterfly breeders annually is less than 32,000 according to the original source quoted.

The claim for Monarch releases was extracted from a New York Times op-ed piece authored in 2006 by Professor Jeffrey Lockwood, University of Wyoming. He estimated 11 million mostly Painted Lady (Vanessa cardui) and Monarch butterflies were released annually by the industry.

In the article, Professor Lockwood noted “nobody knows exactly how many have been commercially produced,” and that he was “extrapolating from one company’s figures.” At the time, it was the only available estimate for an industry that includes releases for ceremonial, memorial and educational use. When asked recently by an IBBA representative how he arrived at the number, Lockwood retrieved an email detailing a discussion with his New York Times editor.

He told the editor he was quoting a website, Butterflies and Blueberries, which presented data from Insect Lore, a popular online destination that serves educators by providing inexpensive Painted Lady butterflies for teaching metamorphosis. It also cited numbers from Monarch Watch, a highly respected organization that provides educational material, tracks the Monarch migration, and offers various butterfly life stages for purchase.

“In the past 32 years, Insect Lore sold 8 million Painted Lady larvae … and Monarch Watch sold 250,000 Monarchs in 8 years,” Lockwood’s emails show. Lockwood said he combined the two numbers and did the math. In his final estimate of 11 million butterflies commercially released per year, only 31,250 were Monarch butterflies.

The 11 million number is presented as fact in the petition to list the Monarch as threatened under the Endangered Species Act. It is the basis for claiming that the industry releases so many Monarchs that they threaten the wild population by possibly introducing diseases, contaminating the gene pool, and interfering with scientific studies.

“That such an unverified claim surfaced in a formal petition before the Secretary of the Interior demonstrates a serious failure in documentation at best,” said Kathy Marshburn, IBBA president.

“It’s misleading and poor scholarship by the petitioners,” said Dr. Tracy Villareal, an oceanographer, part owner of Big Tree Butterflies butterfly farm, and a board member of the IBBA. “The authors made no attempt to determine the composition of the 11 million--how many of each species, for example. Nor did they attempt to contact the author to determine how he arrived at this number. It took me about four hours from my initial email to Professor Lockwood to find out how it was done.”

“Professor Lockwood’s approach was reasonable and the best available estimate at the time,” Dr. Villareal continued. “However, it did not produce the values claimed in the petition. This is an important document with serious outcomes for people’s livelihoods. The petitioners have a responsibility to do their homework. They clearly did not in this case.”

The IBBA is currently conducting a survey of its membership to provide a more accurate tally of Monarch releases by commercial breeders in the organization. Findings will be released at their annual convention in November 2014, in Ft. Lauderdale.

The IBBA is an international, non-profit, membership-based trade association promoting high standards of ethics, competence and professionalism in the breeding of quality Lepidoptera for all purposes. We accomplish this through research, grower education, market development, and habitat conservation and restoration.

Contacts

International Butterfly Breeders Association
Kathy Marshburn, 832-671-4755
kathy.marshburn@yahoo.com
or
Tracy Villareal 361-816-2525
Tracyv001@gmail.com

Contacts

International Butterfly Breeders Association
Kathy Marshburn, 832-671-4755
kathy.marshburn@yahoo.com
or
Tracy Villareal 361-816-2525
Tracyv001@gmail.com