Our Take: Raising Monarchs Who Migrate

Monarch Chrysalises hanging in the lab at
 Beaver Creek. (Photo by Ruth Forsgren) 

A recent article on a study of Monarch Butterflies raised in captivity has a lot of people aflutter.  On June 24, Nation Public Radio shared a story on social media that really took off.  The article (found here) alleged that a graduate student at the University of Chicago ordered Monarchs from a breeder and, "made an accidental discovery: the butterflies had likely lost the ability to migrate." 

Furthermore, the article continued to report that the student, Ayse Tenger-Trolander, 

...studies the genetics and internal biology of migratory monarchs, and she had ordered the butterflies from a breeder that supplies butterflies for educational settings, with the goal of speeding up her experiments. "We fully expected ... that even though they've been bred in captivity, they're still normal North American monarchs," says Marcus Kronforst, her advisor at the University of Chicago.
To their surprise, the breeder's butterflies had rounder, smaller top wings - similar to nonmigratory butterflies. When they were put in a flight simulator, they did not orient south, unlike the wild North American butterflies they'd been raised alongside. The captive-bred butterflies, the scientists realized, were unlikely to migrate. Their findings are published this week in the journal PNAS.

Monarch Caterpillars from Beaver Creek's
caterpillar lab.  Each year we raise between
400-1000 Monarchs from egg. 

We have been raising Monarchs at Beaver Creek Reserve for nearly 10 years.  Each year we train more and more community members on how they can raise monarchs in their own home to help increase the population.  We will go into why this helps later in the article.

Since so many people have questioned whether their own citizen efforts were potentially not producing migrating monarchs, we asked our own specialist. " I think it's quite likely that some captive-raised monarchs may lose their ability to migrate," explained Schwiebert. "Especially those that are sourced from places in the southern United States, Florida in particular, where the majority of the monarch ranchers exist."  Monarchs are able to overwinter in Florida and even parts of southern California due to the year-round mild climate. 

"I think our records at Beaver Creek show pretty strongly that our monarchs do make it to Mexico, considering we've had 10 tag returns in the 20 years that we've been tagging. So I don't think this article is directed at home hobbyists, or small-scale operations like Beaver Creek, who only raise native monarchs from wild collected stock and then release them," continued Schwiebert.

Naturalist Jim Schwiebert reaching up to the southeast
corner of the butterfly house to select butterflies for tagging. 

So for those of you already doing your part to help bolster the Monarch population, or for anyone interested in starting to raise Monarchs, it is best to live catch caterpillars or eggs and then release them as soon as the butterflies emerge from their chrysalis.  But don't worry if the Monarchs that emerge in June, July and even Early August don't immediately head south.  Those early generations stay here to breed and then die.  Monarch hatching in mid to late August and September are the generation that migrates south.

"Butterflies are amazing in general, but the thing that amazes me most is the last generation of Monarchs.  When we release any of the other generations Monarchs, they fly in every direction. But those that emerge in the last generation of Monarchs, those that we tag, from the time that their wings are dry they immediately move to the south side of their enclosures.  When we release them into the butterfly house ahead of tagging them, they mostly congregate on the southern side of the house, and after they are tagged and released, they head south instinctively," commented Brianne Markin, Marketing and Development Coordinator.  "It is important to remember that the migrators are not the first, or even second generation hatched.  This would be like your great-great-great grandchildren knowing where your ancestral home was, without being given directions" continued Markin.

Monarch from Beaver Creek's Butterfly House. 

So how exactly does raising Monarchs at a place like Beaver Creek, or in your own home help increase the population? Monarchs, as well as many other pollinators, have declined in drastic numbers primarily due to the use of pesticides and habitat loss.  Monarch butterflies will only lay their eggs on one plant; milkweed.  The caterpillars will only eat one plant, also milkweed. So if there is no Milkweed, there are no Monarchs. Use of pesticides in areas along the migration route has also contributed to a population decline.  By raising Monarchs from either an egg or a caterpillar we can give them a much better chance at surviving to adulthood in order to reproduce.  

If you are concerned about the plight of the Monarch and want to help, but maybe aren't ready to make the leap to raising them yourselves, there are still plenty of things you can do.  1. Plant Milkweed.  2. Plant More Milkweek. Educate others on planting milkweed or nor mowing ditches or other areas where milkweed grows.  3. Help Beaver Creek by finding eggs or caterpillars. 4. If you have Milkweed growing on your property, bring it to us to feed our hungry horde. The bonus is that our trained volunteers will often find eggs and caterpillars on it as well! 5.  Donate to Beaver Creek Reserve, Journey North or another organization working to preserve Monarch habitats.