In the past, there have been questions about where Northwest monarch butterflies go during their migration journey. But now, a new, solar-powered tracking device — affixed to the butterflies’ bodies with eyelash glue — is helping record their travels.
A project, called Adopt a Monarch, is trying to tag Northwest butterflies with these devices.
“Now, because we can check them daily, or hourly in some instances, we know what they're doing all the time,” said David James, Prosser-based entomologist with the Adopt a Monarch project. He’s tagged monarchs across Australia and the United States since 1976. “You know it’s opened up a whole new window into their migratory behavior from point A to point B.”
Conventional tagging required people to find tagged butterflies with little paper circles fixed on their wings, and then email the insect’s location.
“We used to say with the conventional tags, it was equivalent to a person having their keys in their pocket, in terms of weight,” he said. “These tags are obviously heavier, and it’s more like carrying a backpack.”
Still, the monarchs have been observed flying their normal routes with the new transmitters. They're able to fly all the way to their wintering grounds.
How to tag a butterfly
The new tags fit on the thoraxes of the butterflies.
The tags have small filaments extending from them that act as a transmitter.
“We have to restrain the butterfly and then open its wings,” James said. “And then carefully position the tag on the thorax, and it dries in a minute or so, and then it’s free to go.”
They only work when the sun is shining. That’s when the tags are active, as they don’t have a battery.
People can see where the butterflies are located in real time through a cellphone app, James said.
“With this new technology, I want to use it to answer one of the remaining questions we have about the monarch migration in the Western U.S.,” James said. “We know that most of the monarchs in Oregon go to California … But the interesting thing is that Idaho butterflies, we’ve had one or two turn up in California. But the majority head south and then disappear.”
James said scientists don’t know where the Idaho butterflies go to overwinter, but he theorizes that those butterflies go to Mexico.
“It’s a dream that I didn’t think would come true in my lifetime, to be able to tell where Idaho monarchs are going,” he said. “We think they're going south. So with electronic tagging, we will answer that question.”
Monarch adoption
One hitch? Each butterfly tag costs $200. So, the scientists are asking for help adopting each butterfly, in order for scientists to track more of the insects.
Not all the monarchs will survive, James said. If the tag stops beeping in, or stays in one place too long, that means the butterfly has died, he said.
A shorter life, habitat loss
The tags are so new that not much is known about the effects the tags have on the monarchs, James said.
“Maybe their life is shortened because of the extra weight of the tag,” he said. “They may live a few weeks less and may lay somewhat fewer eggs. There may be some downsides.”
James said monarch butterfly populations are in decline, and better tracking could help improve their habitat conditions.
“A lot of milkweed [that they eat] isn’t where it used to be,” he said. “There has been a decline in milkweed populations. If we know more about what routes they’re traversing [in the spring] … then we’re better positioned to grow milkweed in those areas.”
The Adopt a Monarch’project is all set for its first releases of more than 100 tagged monarchs. The first release will happen in Hayden, Idaho, on Aug. 12.
