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Bugs are silent segment of Yellowstone ecosystem By RACHEL ODELL Jackson Hole News JACKSON, Wyo. (AP) - Insects are under-appreciated and understudied, yet they are the driving forces of almost all ecosystems. They feed larger animals, pollinate flowers and plants, add nitrogen to soil by breaking down decaying matter, disperse seeds and spores, and create homes for wildlife. Important as they are, too little is known about the insects, spiders, caterpillars, and worms of the world, entomologist Mike Ivie said. He led a field trip in Yellowstone National Park recently as part of an annual meeting of the Greater Yellowstone Coalition. Between 3,000 to 4,000 species of insects exist in Yellowstone, Ivie told his small audience. But exactly how many exist and what their functions are is a mystery, mostly because federal funding for insect studies is low priority. "Yellowstone has been very good to me, but I am the only person paid to study bugs in Montana," Ivie said. "That's not enough. All the research is on sexy animals. We don't even have an index of the bugs in Yellowstone." Leaving the road for a meadow near Yellowstone's West Entrance, Ivie excitedly waved his hand across a landscape that was covered with young lodgepole pine. Filled with trees and vegetation, it was void of bison, grizzly bear, elk and wolves. Charred snags, remnants of the Yellowstone blazes of 1988, towered above the new growth. On the ground rotting logs lay on the rocky soil and small wildflowers sprouted from thin, green plants.
"The number of animals that exist in this environment is huge," Ivie said with obvious pleasure. "But you don't see them until you get underground and start digging." Closer inspection proved him right. Tiny, uniform holes on a downed log were proof that bark beetles had bored their way into and out of the wood. Carpenter ants crawled in and out of the holes, chewing the wood on their way. When the ants are done with their job, more insects will arrive to break down the log even more until it eventually crumbles and turns into soil, he said. The bug's life fascinates Ivie, who dedicates his life to studying the invertebrates in the northern Rocky Mountains. At the lowest rung of the food chain, insects feed almost every animal in an ecosystem. Their eggs are protein pods, loaded with fat and nutrients and eaten by bears, squirrels, birds, and more. Insect eggs are copious in the spring, stored underneath bark in fallen logs and on the underside of green leaves. Take the army cutworm moth as an example. The cutworm caterpillars abound in Yellowstone. In their larval stage, the cutworm is a fat, slimy, inch-long worm. As a moth, it is an important food for grizzly bears. The moths migrate to high talus slopes where some grizzly bears spend much of their summers on a heavy moth diet. The advanced social and defensive mechanisms are complex and rival any human society, Ivie said. Bark beetles, for example, covet the sweet liquid excreted by aphids, small insects that feed on plant sap. Carpenter ants also have a sweet tooth for the aphids' liquid, so they protect the small bugs, shielding them from the beetles. "Ants are the most sophisticated chemical and mechanical engines ever built," Ivie said. "If bugs were the size of German Shepherds, humans would never have evolved." Bugs are even the dominant grazers in an ecosystem, Ivie said. Because of their sheer numbers and high metabolism, a colony of bugs can eat as much as some mammals. But American society does not value bugs. From the day we are born, we are taught to consider bugs dirty, disease carriers, and pests. Ivie laments that cultural bias. "I don't get it," he said. "Take the Japanese. There are 700 entomologist clubs in Japan. They love bugs." Unless more people change their attitudes, Ivie predicts science will suffer. "You have to ask yourself, especially in national parks, is the management goal to maintain an ecosystem with all of the species in it, or to maintain a big game park?" he asked. "If it is bio diversity then we're missing a lot by not knowing about these animals." Copyright 1999 Associated Press. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.
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