|Message from the Chief||
Robert N. Wiedenmann and Charles G. Helm
The terms "invasive species" and "exotic species" are often mistakenly interchanged. Although many of the invasive species in Illinois are indeed exotic, not all exotic species are invasive, and not all invasive species are exotic. Exotic species can become invasive when the biotic checks from their native homes do not accompany them into the new habitats--and their populations subsequently grow unchecked. Examples of exotic species that are also invasive range from the gypsy moth, which was introduced into North America in the 1870s, to the soybean aphid, first detected in the Midwest in 2000. Yet, in some cases, an exotic origin is not needed to classify an organism as invasive. Regardless of its source, any species introduced into a new area may be considered an invasive should it spread unchecked, disrupting habitats, affecting native species, and even transforming ecosystems. True costs of the numerous invasives are unknown, but have been estimated to exceed $100 billion per year.
A number of INHS scientists study invasive species, seeking solutions to the problems these species cause. Basic research focuses on understanding the processes of invasion, identifying the traits that allow certain species to become invasive, and determining the characteristics of habitats that predispose them to invasion. Applied research focuses on intervention techniques to stem the growth and spread of these species.
Solutions to invasive species are not easily found, but several Survey projects are beginning to have an effect on selected invasives, such as the biological control project against as purple loosestrife. Other species, such as the zebra mussel, still defy control measures. Likewise, new invasive species will undoubtedly emerge, despite efforts to prevent their arrival into Illinois. Survey scientists will continue to study the ecological and economic costs of invasive species to the state, and our scientists represent the best chance to find long-term, sustainable solutions to those problem species.
Reducing risk of aquatic nuisance species spread via baitfish
Trophic transfer of PCBs: zebra mussels and round gobies
Zebra mussel metapopulation dynamics
Exotic zooplankton in the upper Mississippi River
Implications of the introduction of D. lumholtzi on fish and zooplankton
Effects of common carp on aquatic communities
Investigation of the potential for red imported fire ant (Solenopsis
invicta) impacts on rare or endangered karst invertebrates at Fort Hood,
A Nearctic pest of Pinaceae accidentally introduced into Europe:
Leptoglossus occidentalis (Heteroptera: Coreidae) in northern Italy
Control of the Asian longhorned beetle
Control of the gypsy moth in Illinois
Biological control of purple loosestrife
Biological control of alfalfa blotch leafminer
Impacts of purple loosestrife on nesting wetland birds
Garlic mustard ecology and biological control
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Chen, W., C.R. Grau, E.A. Adee, and X.-Q. Meng. 2000. A molecular marker identifying subspecific populations of the soybean brown stem rot pathogen Phialophora gregata. Phytopathology 90:875-883.
Chick, J.H., and M.A. Pegg. 2001. Invasive carp in the Mississippi River Basin. Science 292:2250-2251.
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