Where have all the butterflies gone?

If you walk through the sweet-smelling butterfly garden at Botanica some morning this week, you’ll spot lots of bees buzzing around the flowers, and probably a diving dragonfly. If you’re lucky, you also may spot one or two small butterflies.

“There is a major decrease in the gardens. You don’t see any butterflies,” Pat McKernan, garden supervisor at Botanica, said last week, and he’s only seen a couple more this week.

A short walk away from the butterfly garden, in the enclosed butterfly house, you’ll see many butterflies of different colors. But even there the pickings are a bit slimmer this summer.

“Even they seem to have trouble supplying us from Florida,” McKernan said. Botanica has been receiving only a couple of different types of butterflies for the house.

The scarcity of the winged beauties is hardly unique to Botanica. Many gardeners and wildlife lovers in Kansas and farther out are noticing what they’re not noticing: the butterflies of summer.

“It’s been a bad year for butterflies in general,” said Chip Taylor, head of Monarch Watch at the University of Kansas.

Taylor doesn’t know why we haven’t seen much of our native butterflies or the 20 types that usually migrate here from Texas. Apart from the long-term general decline in insects worldwide, sudden drop-offs are usually caused by the weather or parasites.

“We’ve had some really weird weather this year,” Chuck Otte, extension agent in Geary County and a keen butterfly watcher, said. The latest weirdness was intense heat in June, which may have hurt the butterflies but also tricked us into thinking it’s later in the summer than it really is, Otte said.

“These things go in cycles. We went from extremely dry to extremely wet. We hardly had a winter. Those kinds of disruptions” can wreak havoc on creatures that rely on particular conditions to survive, he said.

Native Kansas butterflies such as the great spangled fritillary that overwinter as larvae may have suffered from the dry winter, Taylor said. “They need a little bit of moisture or they dry out.”

He’s not sure what happened in Texas to prevent such butterflies as painted ladies, red admirals, variegated fritillaries and sleepy oranges from making the trek north. One theory is that the number of predators of butterflies had built up to take them out, Taylor said.

Predators include wasps, ants, birds, snakes, toads and spiders.

The lack of butterflies seems especially odd this year because all of the rain has proved to be good for wildflowers, said Jim Mason, director of the Great Plains Nature Center in Wichita. The flowers have been exuberant, with ready food.

Typically in early summer at the center, “we see some common painted ladies, checkerspots – which are the little orange and black ones – eastern tailed blues, hairstreaks — gray hairstreaks, olive hairstreaks, coral hairstreaks. Those are always a joy when we get to see those. They’re real pretty,” Mason said. But they haven’t been spotted much this year.

Mason also watches especially for regal fritillaries on property he owns in Osage County. “I think I saw one earlier in the season but not any since. That’s been a little disheartening to me, because I always count on seeing regals on our place at least.”

The butterfly counts in Harvey County and on the Tallgrass Prairie Preserve near Strong City in central Kansas showed a decrease this year, Mason said. But that could be because the counts, which are done on the same day each year, fell between generations for a lot of species this year, he said.

Another oddity about the lack of butterflies is that Kansas has been buzzing with talk of higher insect numbers because of the mild winter. But that only benefited bugs that overwinter here and that are vulnerable to hard freezes, Mason said. Many of them, such as mosquitoes, are not terribly wanted.

But when people don’t see butterflies, they get sad or worried.

“It’s hard,” Otte said of trying to figure out causes and effects. “In 100 years we might be able to tell you what it means. It could be a blip. It could be part of an ongoing trend. It does concern me. … On the long haul, there are a lot (of insects) that are in a lot of serious trouble.”

The steep decline in insects is blamed mainly on pesticide and other chemical use, urban development and destruction of habitat. The trend affects the food sources of some birds and animals and the pollination of food crops.

At the top of the list of causes, Mason says that he’s “fairly certain some category or combination of chemicals” is getting released into the environment through agricultural use or association with our modern society that is “getting away from us or being disposed of or whatever. We need to have a conversation about it.”

Mason urges the use of native plants in landscaping and limiting the use of pesticides. “In terms of what people can do around home, that’s about the most direct involvement that they can have.”

And there is good news: The number of butterflies in Kansas is starting to build up at this point of the season, Taylor said.

And “the fact that there were very few of them early in the season is kind of beneficial in one way,” he said: Their predators also got a slow start since they didn’t have the butterflies to eat, so there won’t be as many predators and parasites around late in the season to cause problems.

“To me, the flying season really starts to pick up later in August and into September,” Otte said. Hummingbirds, similarly, don’t usually start showing up until late July or early August.

But don’t get your hopes high for seeing lots of monarch butterflies this year. Taylor is predicting low numbers of them migrating south through Kansas in September. After the population bounced back well last year, a late-winter storm in Mexico wiped out many.

This story was originally published July 21, 2016 at 1:12 PM with the headline "Where have all the butterflies gone?."