Austin's Efforts To Feed An Outsized Migration Of Monarch Butterflies Will Be Tested This Fall

Nov 2, 2018

Take a look around the next time you’re outside and you might see wings of orange and black fluttering in the sky.

Monarch butterflies are making their way through Texas to wintering spots in Mexico. The butterfly's population has plummeted over the last 20 years, so Austin and a string of other communities have instituted land-use policies to help them out. This fall will be a big test to see how much those efforts help.

Think of Austin as a rest stop for migrating monarchs. Just as you need to fill up your tank when you drive down I-35, monarchs need to stop to eat. In the fall, they fill up on the nectar of certain flowers; in the spring, it’s milkweed they need to lay their eggs on. Austin adopted policies to grow milkweed in the spring and summer and encourage the growth of native pollinator plants.

“I think people have a conception that it always has to be large landscapes that are [butterfly] preserves. But really, just a few hundred feet matter when you’re going from one section of town to the other,” says LaJuan Tucker, a park ranger with the City of Austin Parks and Recreation Department.

This year, the city’s butterfly gardens at Zilker Park, the Mueller development and the Lady Bird Johnson Wildflower Center might be a little more busy than usual.

More monarchs are expected to fly through Austin than have in 10 years, thanks to exceptionally good weather up north, where monarchs lay their eggs during the summer. Preliminary estimates say 180 million of them could pass by this fall, twice the number from last year.

“[The number] this year is going to represent as many monarchs as we can produce with the current amount of milkweed and the absence of weather disasters,” says Tierra Curry, a scientist with the Center for Biological Diversity.

Even with the weather cooperating, monarch numbers are still well below the 225 million needed to stabilize the population.

That’s what makes this fall a true test of how much places like Austin can really help. Curry says this season will show how well these little oases of food created along the flyway can help sustain such a big generation of butterflies.

If a lot of monarchs don’t reach Mexico, it could mean they’re not finding enough sustenance on their way. If they do, conservationists can be more confident that efforts cities like Austin are making actually help.

It’s especially important because things are expected to only get worse for the monarchs weather-wise.

“By in large, what’s going to happen is that we’re not going to see these favorable conditions come together very often in the future," says Chip Taylor, director of Monarch Watch at the University of Kansas. “Maybe never. It depends upon how fast things change out there.”

The change he’s talking about, of course, is climate change.

Global warming is expected to bring more extreme weather like droughts, freezes and wildfires all up and down the monarchs’ route. That will further threaten their numbers.  

That's one reason many conservationists would prefer to see the butterflies listed as endangered species. That would create federally mandated laws to help them.

What Austin and other communities are doing is essential, Curry says, but "it would be awesome if the was a big coordinated response to save them.”  

The U.S. Fish and Wildlife Service is supposed to decide on whether to list the monarch as an endangered species next year. Given the Trump administration’s record on conservation, and its plan to erect a wall through a monarch preserve along the U.S.-Mexico border, Curry doesn't think the butterflies will be listed.

So, monarchs pit stops like the ones you can grow in your backyard may be the next best thing – if not to restore the species, then at least to keep them on a sort-of life support in the face of growing threats.