SCIENCE -- October 17, 2011 at 4:34 PM ET
Lost Ladybug Spotted On Long Island Farm
After it had gone missing for decades in New York state, the nine-spotted ladybug was found in Long Island. Photo by AP/Cornell University, Ellen Woods.
Once so ubiquitous it was named New York's official state insect, the nine-spotted Ladybug has gone missing there for nearly three decades. That is, until just recently, when citizen scientist Peter Priolo spotted the bug on a Long Island organic farm.
Priolo, a volunteer with Cornell University's "Lost Ladybug Project," found the elusive insect at the Quail Hill Organic Farm. He had been leading a group of 15 volunteers on a search for ladybugs, and was about to call it a day.
"On the way back to drink lemonade, I stopped at a planting of sunflowers," Priolo said. He thought the flowers might contain aphids, a favorite ladybug food. He didn't see any aphids, but, toward the top of the plant on the stem of a leaf, he spotted something even more intriguing.
"I thought it looked like a candidate for a native species," he said. "I had never seen it before. Then I took a picture before I disturbed the scene." He put it in a mason jar and took it home for further research. As he sifted through photos and began the formal identification process, he began to realize what he had: a nine-spot. "I was jumping around my living room," he said.
On a follow-up trip to the farm, 20 more adults were spotted.
The nine-spot is a star of the ladybug world. It is specifically mentioned in the New York state Constitution, a "flagship species" according to Cornell University Professor John Losey. Losey founded the Lost Ladybug Project to investigate the declining numbers of native ladybug species, including the nine-spot. He has since mobilized volunteer enthusiasts nationwide to take part in expeditions aimed at gathering, then documenting, various ladybugs.
The nine-spotted ladybug is the most visible symbol of the decline of native ladybug species, which are at risk of being driven out by their non-native brethren. When natives get edged out by non-natives, a tool for natural pest control is lost. Ladybugs prey on crop pests like aphids and mealybugs. Each species eats different pests, however, so effective pest suppression depends on a diverse population.
Losey's goal is to track the natives relative to the non-native varieties. He suspects that the native nine-spot, may be getting squeezed out by the non-native seven-spotted ladybug.
"The timing of when the nine-spot declined and the seven-spot increased is very, very close," he said. His hunch is that the decline of the nine-spot can be traced directly to the introduction of the new species.
The nine-spot is not gone altogether. Though scarce in New York, researchers have seen a steady population of nine-spots in the Midwest and West. Louis Hesler, a USDA scientist who studies crop pests like aphids, offers one possible explanation for what this rediscovery may mean.
"There have been a lot of (nine-spotted ladybug) finds from non-agricultural areas, where, because of the mountains, you can't farm or there is a lot of open space. We thought that non-cropped areas provided refuges, without a lot of other species competing. This find was in a fairly developed, highly cropped area. Makes us rethink."
The fact that more adults were found at the farm is a source of optimism for Losey. "We're hopeful that we're seeing it in a viable population, that some sort of rebound is beginning," he said.
Losey considers this new finding a victory not just for ladybugs, but also for citizen science. With such a broad area to cover and scarce resources available to hire scientists and conduct field research, "this type of data couldn't be gathered in any other way," he said.
The first nine-spotted seen in nearly 30 years was found on a sunflower stem. Photo by Peter Priolo.