The Ecological Society of America is proud to host its 86th Annual Meeting this year in Madison, Wisconsin from August 5-10. Over 3,000 scientists will attend and more than 1500 scientific presentations will be given during the week. Below is a sampling of some of the papers which will be presented on insects. Other topics to be covered during the meeting include climate change, ecological forecasting, invasive exotic species and agriculture. The meeting theme is “Keeping All the Parts: Sustaining and Restoring Complex Ecosystems.”
“Weeds, Bugs, and Mice: Why Two Biocontrol Insects Failed.”
Invasive exotic plants have become an expensive problem for land managers in many parts of the US. Using biological controls, such as the introduction of an insect to eat the offending plant, has become a popular control method in many regions of the country because biological controls are often less expensive and potentially safer than chemical herbicides. The current success rate for biological controls is very low, however, and though many biocontrol insects successfully establish and spread, they often fail to suppress the targeted weed. Amanda Stanley from the University of Washington will discuss her research on the topic and explore interactions between a well-known invasive, spotted knapweed (Centaurea maculosa), two seedhead gallflies used as biocontrols (genus Urophora), and the native deer mouse (Peromyscus maniculatus). Some researchers have wondered if the mice are eating the gallflies and preventing them from controlling the offensive weed. Stanley’s work suggests that, although gallflies have become plentiful since their introduction 30 years ago, they fail to control the knapweed because they attack the target plants during a robust stage of life. The real effect of the mice on the gallfly numbers is negligible.
Time and Location: Wednesday, August 8, 2001. 8:00 AM to 12:00 PM. Hall of Ideas H.
“Oviposition site selection by the mosquito, Culiseta longiareolata, in response to chemical detection of a predator, Notonecta maculata.”
Humans spend large amounts of time and money trying to control or deter mosquito populations. Leon Blaustein (University of Haifa) and his colleagues have been investigating how natural selection may influence mosquitoes’ choice of breeding sites. Using outdoor pool experiments, they observed the behavior of two related insect species commonly found in the Middle East. One species, the mosquito Culiseta longiareolata, is highly vulnerable to a predator known as Notonecta maculata, which belongs to the group of insects commonly known as backswimmers. The other species, a midge known as Chironomus riparius, is far less vulnerable to being eaten by this same predator. Culiseta, the researchers found, avoids laying eggs in pools which contain the Notonecta; the mosquito is able to pick up on chemical cues given off by the predator. Blaustein and his colleagues will now begin assessing how these same chemicals might be applied to other mosquito breeding sites in order to deter mosquitoes. Preliminary results show that the chemical will repel Culiseta for about eight days.
Time and Location: Tuesday, August 7, 2001. 8:00 AM to 11:45 AM. Hall of Ideas E.
“Go towards the light: butterfly species richness increases following ponderosa pine restoration.” Ecosystem restoration projects often overlook the importance of insect populations, even though invertebrates play a critical role in ecosystem structure and function. Butterflies are not simply lovely, but also contribute significantly to energy transfers and pollination processes in ecosystems, and may provide important information about interconnections within restored systems. Amy Waltz from Northern Arizona University has been researching how efforts to restore ponderosa pine areas in the Southwest have affected butterfly numbers. The areas studied have been restored using prescribed fire and reduced tree densities, which has helped to increase species richness and abundance in the understory areas of the forests. Sampling done in the restoration zones showed a 100% increase in adult species and a 400% increase in butterfly numbers. Although multiple factors may be contributing to the changes in butterfly distributions, Waltz’s work indicates that the butterflies were most likely attracted to the increase in light. The amount of nectar did not increase much in the first year after restoration treatments were used, but in the second year nectar flowers increased significantly, suggesting that the increase in these resources also plays a role in the butterfly increase. Waltz reasons that increased butterfly abundances may indicate changes in understory plant diversity and may also reflect increases in other pollinator groups within restored forests.
Time and Location: Friday, August 10, 2001. 8:00 AM to 11:45 AM. Hall of Ideas I.
“A comparison of costs inflicted and benefits given by floral visitors to Chilopsis linearis.”
As the public’s appreciation of pollination grows, so too, do the questions about bees. Often assumed to be the best, most effective pollinators, honeybees have long been used to pollinate all kinds of crops. Sarah Richardson from the University of Arizona set out to measure the relative efficacy of three common Western visitors to flowers: native bumblebees (Bombus sonorus), introduced honeybees (Apis mellifera), and indigenous nectar-robbing bees (Xylocopa californica). She wanted to know if visitors that entered the flowers, such as honeybees and bumblebees, were always better pollinators than nectar-robbers. Using some previously unvisited blooms of a desert willow (Chilopsis linearis), she discovered that bumblebees, which spend a significantly longer time in flowers, are very effective pollinators. In contrast, the number of pollen grains on a stigma after a visit from a honeybee was not very different from that left by a nectar-robbing bee. In fact, the honeybees caused the stigmas to close, which often prevents later pollination. Richardson's work demonstrates that a floral visitor which appears to have a mutualistic relationship with a plant can actually give as little benefit as a nectar robber.
Time and Location: Wednesday, August 8, 2001. 1:00 PM to 4:45 PM. Hall of Ideas F.
For more information about these presentations and other Annual Meeting activities, please visit the ESA website at http://esa.sdsc.edu/madison/
The Ecological Society of America (ESA) is a scientific, non-profit, 7,800-member organization founded in 1915. Through ESA reports, journals, membership research, and expert testimony to Congress, ESA seeks to promote the responsible application of ecological data and principles to the solution of environmental problems. ESA publishes three scientific, peer-reviewed journals: Ecology, Ecological Applications, and Ecological Monographs. Information about the Society and its activities is published in the Society’s quarterly newsletter, ESA NewSource, and in the quarterly Bulletin. More information can be found on the ESA website: http://esa.sdsc.edu.