Tagged monarch butterfly identified as first Pacific Northwest migrant to reproduce in Southern California
When Akimi King found monarch butterfly eggs in her garden near Klamath Falls, Oregon, in August 2017, she had no idea one would make western monarch history as the first Pacific Northwest migrant observed reproducing in California.
Since monarch survival in the wild is less than two percent, King, a biologist in the Klamath Falls Fish and Wildlife Office, raised the larvae indoors for the next month.
On September 3, 2017, two adult monarchs emerged from the many pupating caterpillars King was nurturing. Within hours, the male and female were ready to fly. King affixed a small coded tag on the lower wing of each and set them free to migrate to the central California coast.
“I didn’t know if I’d hear about the tagged butterflies again,” said King. “I was hopeful maybe one would be seen wintering along the Pacific coast.”
The tags were provided by entomologist Dr. David James as part of the Monarch Tagging Program through Washington State University.
James has researched migrating monarchs in the Pacific Northwest since 2012 and found the majority of tagged butterflies are observed in overwintering colonies along the Pacific coast from Carpinteria north to Bolinas.
However, none had been observed on milkweed or reproducing.
“Typically fall migrating butterflies do not reproduce when they reach their winter roosts in California,” said James. “In February and March they move inland to breeding areas and their offspring begin the multi-generation journey north in May and June.”
Year-round breeding populations of western monarchs are most often found in Southern California, but recent speculation among researchers was that monarchs were moving north to Los Angeles and Santa Barbara. But there was no proof.
Nineteen days after King released the tagged butterflies in Klamath Falls, James got his proof -- 545 miles to the southwest.
Cathy Fletcher lives in Santa Barbara and grows a large pollinator garden, raising about 150 monarchs yearly.
On September 22, 2017, as Fletcher was carrying a milkweed plant in her garden an adult butterfly landed on the leaves.
“As the monarch flitted around the plant I was holding, I marveled how she was earnestly laying eggs undeterred by my presence,” recalled Fletcher. “When I realized the butterfly was tagged, I gently plucked her off the milkweed to record the code.”
After reporting tag number B6679, Fletcher released the butterfly back into the garden. It continued to lay eggs for eight days before it finally disappeared.
In butterfly science, B6679’s migration was a big deal.
Realizing how unique this observation was, James wrote and submitted a report to the Journal of the Lepidopterists’ Society,where it was published this past September.
“This female monarch, number B6679, is exceptional in being the first migrant from the Pacific Northwest confirmed to be actively reproducing within the winter breeding population of monarchs in Southern California,” said James.
King was thrilled one of her home-reared monarchs made the incredible journey into western monarch history.
Of 114 tagged butterflies King released last year, B6679 was one of five found in California, which is four times the average observation rate.
“Who knows?” said King. "Maybe one of B6679's great-grand-butterflies will visit my garden this year and continue the cycle.”
Learn more about the Western Monarch on our page, 'The Monarch Butterfly Story..."
Press release provided from the Susan Sawyer, Klamath Basin Public Affairs Officer, Klamath Basin National Wildlife Refuge Complex.