Where Have All the Ladybugs Gone?

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The decline in the U.S. ladybug population, particularly the nine-spotted ladybug Coccinella novemnotata, has been going on since at least 1997. . Photo courtesy of Todd A. Ugine

The next time you see a ladybug, do a farmer a favor. Whip out your smartphone, take pictures of it, and email the photos with the location to John Losey.

Losey is the director of the Lost Ladybug Project and will add your picture to the more than 34,000 ladybug images he has received. The project is a citizen science effort that Losey runs out of his lab at Cornell University in Ithaca, New York, where he's an associate professor of entomology. Native ladybugs have been in serious decline since the mid-1970s, and Losey is seeking to document where remaining populations are being seen, where they're not being seen, all to help determine the reason for their decline.

"Don't worry about whether the photos are in focus and don't self-select the images you send," said Losey, emphasizing he would like to see any and all pictures of ladybugs. "They don't have to be worthy of the cover of National Geographic," he added. Different species of ladybugs — Losey calls them "lady beetles" because these "bugs" are actually members of the beetle family — have distinct markings, and Losey said project team members can almost always identify the species regardless of the quality of the photo.

Another important consideration for citizen scientists, Losey added, is don't just look for species that are rare. "It is equally as important for us to know where the rare ones are as where they are not," he said. "It also doesn't matter whether your photos are of native or non-native ladybugs," he continued. "All the photos constitute important data points." (Download a photo submission form and to get tips on how to be the eyes of Losey and his team.)

From common to rare

A 9-spotted ladybug crawls along a flower
Once a common presence in gardens, the 9-spotted ladybug has become a rare sight. Photo courtesy of Todd A. Ugine

Once a common presence in gardens, the 9-spotted ladybug has become a rare sight. (Photo courtesy of Todd A. Ugine)

Losey became aware of the decline in ladybugs when he arrived at Cornell in 1997 as a specialist in biological controls for agricultural crops. "When I heard a ladybug hadn’t been seen on Long Island in 20 years, it stuck in my head," he said. "I wondered how we could go from ladybugs being so common to so rare." Something else nagged at him that increased his desire to study the plight of ladybugs. The nine-spotted ladybug, Coccinella novemnotata, is the New York state insect.

Curious about the anecdotal information that ladybugs had disappeared in New York, Losey started the Lost Ladybug Project in 2000 and began looking for answers to their decline. He sought answers through surveys, in secondary school classrooms, and by conducting various ladybug blitzes. His research attracted National Science Foundation funding, and in 2004 he launched the Lost Ladybug Project website.

As the project evolved, Losey learned that the disappearance of these little insects wasn't limited to New York. The situation was the same across the country. The implications, he knew, were significant.

There are more than 4,500 ladybug species worldwide and more than 500 in the United States. Almost all of them are natural predators that play a critical role in controlling agricultural pests. These pests include aphids (the favorite food of ladybugs), scale, white flies and spider mites. During its lifetime, a ladybug may consume as many as 5,000 aphids. Their voracious appetite has been critical to controlling pests on forage crops such as alfalfa and clover and food crops such as wheat and potatoes, Losey said.

Invasive ladybugs

The Asian ladybug, Harmonia axyridis
The Asian ladybug, Harmonia axyridis, may have contributed to the dwindling population of native U.S. ladybugs. Stu's Images/Wikimedia Commons

Scientists haven't been able to determine the exact cause of the decrease in native ladybugs. Some studies have noted that the decline of several native species generally corresponds to the increase and spread of the seven-spotted ladybug from Europe (Coccinella septempunctata). It was imported and released several times and in several places from the 1950s through the late 1970s, according to Robert Gordon, a retired USDA entomologist. The Asian ladybug (Harmonia axyridis) has also been released into the U.S. multiple times since 1916 on the East and West Coasts and along the Gulf of Mexico, according to Gordon.

However, other scientists say there is circumstantial evidence that these two non-native ladybugs were accidentally introduced at shipping ports in North America. They also contend that it's unclear whether these introductions, however they occurred, were successful. Regardless of how they arrived, Losey contends the non-native ladybugs have proliferated so successfully that they have pushed native ladybugs out of agricultural fields and into non-agricultural areas, although he accepts there's not general agreement on this theory.

As a result, populations of some native ladybugs are now greatly reduced and are small, isolated and scattered, Losey said. "Small scattered populations generally mean a species is in a downward spiral," he said. Based on what has happened with other organisms that have faced similar types of population fragmentation, this is not a good sign for native ladybugs, Losey added.

Cyclical populations

Nevertheless, the research has produced some findings that give him reason to be hopeful for the diminutive little ladybug. "We do occasionally get reports of rare sightings in consecutive years, and when that happens it indicates that the populations, though small and isolated, seem stable," he said. That gives him optimism for the short term. If the project team can show it's helping to stabilize these populations even further, he said he'll feel more optimistic about the long term.

There are also other reasons Losey finds to be hopeful about the health of the nation's important agricultural crops and the future for native ladybugs. While ladybugs play a major role in suppressing harmful insects, many other predators and parasitoids also prey on aphids in agricultural fields. Losey also agrees with other scientists that the introduced ladybug species are due for a decline themselves.

How to help

Magnifying glass over a ladybug on a plant
Researchers need help tracking ladybug populations for the Lost Ladybug Project. Christian Musat/Shutterstock

If you'd like to help preserve native ladybug species and restore populations of the species in the most serious decline, Losey invites you to participate in his citizen science project. Who knows, maybe you could have the same good fortune as Peter Priolo who found a nine-spotted ladybug on Long Island in 2011. It was the first documented sighting in New York in 29 years. It's one of only 285 sightings of this once-common species that have been reported to the Lost Ladybug Project from anywhere in North America.

Losey encourages people to look for ladybugs in their yards, gardens, parks or on outdoor walks and mail their photos to the Lost Ladybug Project. If you want to do more, you could become one of what Losey calls his super spotters. "These are people who are very, very interested in the project," Losey said. "Besides sending in hundreds of photos, and even a thousand in one case, these volunteers give local talks about ladybugs," Losey said. If you're interested in being a super spotter, email Losey at ladybug@cornell.edu.

All of these efforts, Losey said, are helping the project team get a picture of where native species are now in terms of new ranges and distributions. That picture, Losey said, is coming together in the form of a national map of ladybug populations. Some volunteers will even get a special reward for helping the project get a handle on what’s happening to ladybugs. Losey will be contacting some of them to release lab-raised natives back into the wild.