Insects are an infrequent focus of conservation studies (Samways 1994, New 1997, Xerces Society http://www.xerces.org/home.htm). Generally speaking, insects have not been central to discussions in conservation biology. The public finds mammals and birds much more appealing than little “creepy crawlies.” Most people view insects as “bugs” or pests because they bite and invade our space with little acknowledgement of human presence or power. Of course, as Jeff Boettner points out in his article, there is an entire industry devoted to killing insects. In the end, we cannot eradicate insect species because they appear to evolve faster than people can invent new and more deadly chemicals. Despite most people’s adversarial relationship with insects, there are many important ways in which insects enter the conservation dialog.
First, insects are everywhere (aside from ocean environments). Because they are easy to find, insects are ideal for nature studies, especially with young children. Awareness is the first step towards conservation; therefore, the time that children spend catching and watching insects may have a much greater life-long impact than we generally appreciate. Richard Wolniewicz’s article demonstrates how rewarding simple observation can be when one starts to explore biodiversity literally at the front door. Richard’s count of the moths or macro lepidoptera that have come to his porch light approaches 200 species and rumor has it that if one gets serious enough to include the families of tiny moths or micro “leps” then the count could go up by 4-fold!
In addition to moths and butterflies, dragonflies and damselflies are very popular with the public because they are brightly colored, active by day, and large enough to be seen in the field easily. There now good field guides for these “charismatic mega-invertebrates”. Organized by the North American Butterfly Association, (NABA http://www.naba.org/), a growing group of butterfly enthusiasts is very concerned with conservation. These watchers participate in the 4th of July butterfly count hosted by NABA and help monitor Monarch migrations (Monarch Watch http://www.MonarchWatch.org/ ). Bumblebees, tiger beetles, and ground beetles are some of the other insect groups that have drawn the attention of field naturalists and conservation biologists.
Second, insects are critical components of terrestrial ecosystems. E.O. Wilson’s work has documented the numerical and biomass dominance of ants. This perspective was showcased in the 1997 PBS television special titled “The Little Creatures Who Run the World” (but see Terborgh 1998). In terrestrial systems, the work of Buchmann and Nabhan has called attention to the keystone role of insects as pollinators (Buchmann and Nabhan 1997, http://www.desertmuseum.org/conservation/fp/publications.html , also see Kremen and Ricketts 2000). One threat to native pollinators has been the development of industrial pollination in which honeybees are trucked long distances to provide pollination services (Whynott 1992). Industrial pollination has the side benefit of industrial honey production (Whynott 1992), but honeybees compete with native species and have established themselves in the wild acting as an invasive species. Pesticides (another byproduct of industrial agriculture), habitat fragmentation, and climate change can also impact native pollinators, which, in turn, have implications for crop plants and rare native species. (http://www.desertmuseum.org/conservation/fp/monitor_threats.html).
Without native insect pollinators, there is increased risk that some crops and native plants would fail to produce fruits. A recent update about pollinators and conservation can be found in the online journal Conservation Ecology in the first issue of Volume 5 (http://www.consecol.org/vol5/iss1/index.html). Of particular interest is Cane and Tepedino’s (2001) paper which synthesizes the results of a workshop on pollinator services sponsored by the National Center for Ecological Analysis and Synthesis and indicates the difficulties in documenting changes in pollinator populations. (See http://www.consecol.org/vol5/iss1/index.html for the other papers).
Third, insects are used to monitor ecosystem health. In this issue Fred SaintOurs’s overview article about dragonfly conservation also touches on a standard approach to monitoring stream health by using macroinvertebrates. Karr’s work (1981, 1986) on the Index of Biological Integrity has been widely adopted for use with aquatic macroinvertebrates that are dominated by insects (Barbour et al. 1999, http://www.epa.gov/owow/monitoring/rbp/), as any fly fisherman can attest. Stream and rivers are among our most altered and threatened ecosystems. Insect will continue to play a key role in habitat monitoring because they integrate environmental conditions over time and space. In the ecosystem level, butterflies (Parmesan et al. 1999) as well as Drosophila (Foote and Carson 1995, Linde and Sevenster 2002) have also been used to monitor the environment.
Finally, insects have played a role in the development of two central concepts in conservation biology: island biogeography (Simberloff and Wilson 1969a,b, Simberloff and Wilson 1970) and metapopulation theory (Hanski 1991, Walhberg et al. 1996). Let’s hope that Boettner’s work on invasive insects and biocontrol will shed new light on how people can manage invasive species and protect native habitats and species more successfully.
I would be remiss if I did not point out the rare and endangered species of insects in Massachusetts, including the American Burying Beetle (Nicrophorus americanus) and the Northeastern Beach Tiger Beetle (Cicindela dorsalis) (see http://www.state.ma.us/dfwele/dfw/nhesp/nhrare.htm for a complete list). I believe that invertebrates will continue to suffer from scant attention compared to their vertebrate relatives such as the peregrine falcon, but I hope that this editorial and the current issue of Conservation Perspectives illustrate some of the exciting opportunities to conserve insects and further advance the cause of conservation biology. By any measure, insects are species-rich, which adds to their allure and suggests exciting new possibilities for discovery. Perhaps it is no accident that some of the most important leaders in conservation biology, including Paul Ehrlich, E.O. Wilson and Daniel Janzen, started their careers by studying insects.
People who want to know more about invertebrate conservation can join the Xerces Society and read their publication, Wings http://www.xerces.org/Wings/wings.htm, which has a wonderful series of essays about conservation of the small creatures.
Barbour, M.T., J. Gerritsen, B.D. Snyder, and J.B. Stribling. 1999. Rapid Bioassessment Protocols for Use in Streams and Wadeable Rivers: Periphyton, Benthic Macroinvertebrates and Fish, Second Edition. EPA 841-B-99-002. U.S. Environmental Protection Agency; Office of Water; Washington, D.C. http://www.epa.gov/owow/monitoring/rbp/index.html
Buchmann, Stephen L. and Gary Paul Nabhan. 1997. The Forgotten Pollinators. Island Press 320 pages.
Foote, David and Hampton L. Carson Drosophila as Monitors of Change in Hawaiian Ecosystems http://biology.usgs.gov/s+t/noframe/t233.htm
Hanski, I. 1991. Single-species metapopulation dynamics: concepts, models and observations. Biological Journal of the Linnean Society 42:17-38.
Karr, J.R, 1981, Assessment of biotic integrity using fish communities: Fisheries, v.6, p. 21-27.
Karr, J.R., Fausch, K.D., Angermeier, P.L., Yant, P.R., and Schlosser, I.J., 1986, Assessing biological integrity in running waters—a method and its rationale: Illinois Natural History Survey Special Publication Number 5, 28 p.
Kremen, C. and T. Ricketts. 2000. Global perspectives on pollination disruptions. Conservation Biology 14: 1226-1228
Linde, K. van der; Sevenster, J.G. (2002). Drosophila diversity over a disturbance gradient. Proceedings of the Section of Experimental and Applied Entomology of the Netherlands Entomological Society (NEV) 13: 51-56.
New T. R. 1999. Butterfly Conservation. Oxford University Press
Samways Michael J. 1994. Insect Conservation Biology. Chapman & Hall. 358 pages.
Parmesan, C., N. Ryrholm, C. Stefanescu, J.K. Hill, C.D. Thomas, H. Descimon, B. Huntley, L. Kaila, J. Kullberg, T. Tammaru, J. Tennent, J.A. Thomas, M. Warren (1999). Poleward shift of butterfly species’ ranges associated with regional warming. Nature 399:579-583.
Simberloff, D. and E.O Wilson. 1969a. Experimental zoogeography of islands: defaunation and monitoring techniques. Ecology 50:267-278.
Simberloff, D. and E.O Wilson. 1969b. Experimental zoogeography of islands: the colonization of empty islands. Ecology 50:278-296.
Simberloff, D. and E.O Wilson 1970. Experimental zoogeography of islands: a two-year record of colonization. Ecology 51:934-937.
Terborgh, J. 1988. The big things that run the world. Conservation Biology. 2:402-403.
Wahlberg, N., Moilanen, A. and Hanski, I. 1996. Predicting the occurrence of species in fragmented landscapes. Science 273:1536-1538.
Whynott, Douglas. 1992. Following the Bloom: Across America With the Migratory Beekeepers. Beacon Press. 210 pp.
All photographs copyright Richard Wolniewicz
The views and opinions expressed in all articles that appear in "Conservation Perspectives" are those of the authors and do not necessarily reflect those of NESCB.