Essays on Invertebrate Conservation
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WINGS ESSAYS ON INVERTEBRATE CONSERVATION THE XERCES SOCIETY FALL 2009 CONTENTS Introduction Scott Hoffman Black Page 3. Piggyback Conservation Claire Kremen Invertebrates are generally overlooked in many conservation efforts. Despite their importance they often benefit by chance rather than intention.Page 4. Butterflies After Fire: Ashes or Phoenix? Scott Hoffman Black Controlled fire is widely used to maintain healthy grassland, but careful planning is needed to avoid harming butterflies.Page 9. Game Birds, the Farm Bill, and Invertebrates: A Win-Win-Win Situation Wendell Gilgert In many regions of North America, hunting has been a major motivation for cre- ating habitat that benefits insects. Page 14. Missed Opportunities on the Grassy Knoll: Saving the Northeast’s Grassland Invertebrates Sacha Spector Government grants are given to manage farm grasslands for wildlife, and such management can also offer great potential for invertebrate conservation. Page 19. Can a Bird Save a Living Fossil? Piotr Naskrecki Horseshoe crabs seem like relics from a prehistoric era. Their future is closely tied to the fortunes of a migratory shorebird, the red knot. Page 24. Xerces News Xerces adds new regional offices; major grants awarded to the Society to protect pollinator habitat; and a change in the basic membership rate. Page 29. 2 WINGS Introduction Scott Hoffman Black During the 1990s I worked for conserva- In this issue of Wings, we explore tion organizations devoted to protect- the idea of “piggyback” conservation ing big places and big animals: ancient — how the conservation of one species forests, wild rivers, spotted owls, salm- can lead to the protection of others. The on. Because it was focused on saving first essay lays the groundwork by dis- large, charismatic wildlife, the con- cussing what this concept means and servation community within which I brings us full circle to an instance of worked did not think much about tiny vertebrate conservation piggybacked creatures such as insects. But with my onto pollinators. We look at the situa- background in ecology — specifically, tion of a rare butterfly that literally can- working with invertebrates — I often not escape the heat during controlled thought about how our work provided fire to improve habitat. Two articles ex- habitat for these little-thought-about plore the ways that the Farm Bill’s pro- animals. When you protect a large land- visions for providing bird habitat may scape, you are, of course, providing for help or harm insects depending on the invertebrates. By not logging, building circumstances. Last, we delve into the roads, or over-grazing, you are protect- case of horseshoe crabs, for which sur- ing habitat for both big and small, but vival may depend on efforts to protect the latter are seldom part of the plan. the red knot, a migratory shorebird. Conservation programs for animals such as the bobwhite quail can benefit invertebrates — and may in fact rely on them for success — but often overlook them during planning. Pho- tograph by Bryan Eastham, courtesy of iStockphoto. FALL 2009 Piggyback Conservation Claire Kremen When I was a young staff member at members of an ecosystem whose habi- the Xerces Society in the early 1990s, tat needs aren’t being explicitly consid- our constant challenge was to generate ered. For example, the excellent work interest in conserving invertebrates, of Hawai‘i-based entomologist Dan their habitats, and the critical functions Rubinoff clearly showed that conserva- they provide for maintaining biodiver- tion planning for the California gnat- sity and ecosystem health. Nearly two catcher (Polioptila californica), intended decades later, it is still my instinct to as a flagship for California’s endangered “piggyback” the goals of insect conser- coastal sage-scrub ecosystem, did not vation onto other more popular or at- adequately protect several rare moth tention-getting objectives. But is that species, including the electra buckmoth still necessary? Some recent events (Hemileuca electra), a subspecies of which have made me wonder whether per- is found only in this scrub ecosystem. haps — just perhaps — insects and other The buckmoth required more land for “orphan taxa” may yet take center stage survival than the gnatcatcher did. in conservation efforts of the future. In my work designing protected But first, let’s talk about piggyback- areas in Madagascar, which first started ing, the insect conservationist’s fore- during my days with the Xerces Society most tool, in which we use existing (see the summer 1992 issue of Wings), I projects, legislative efforts, or environ- had several opportunities to piggyback mental policies that promote conserva- insects onto other conservation work. tion objectives of relatively wide public Madagascar is one of the “hotspots” of interest to advance more-esoteric con- global biodiversity. In this fabulous is- servation goals. The time-honored “um- land environment, evolution acting in brella species” approach embodies this isolation from the rest of the world has concept. In theory, choosing high-pro- produced a unique and highly diverse file, charismatic, and area-demanding flora and fauna; in many groups, more species such as grizzly bears, pandas, than 90 percent of species are found or golden lion tamarins as “flagships” only in Madagascar. One group of but- for conservation has the incidental ef- terflies, the satyrines, is represented on fect of protecting many other species. the island by a very large number of In the United States, the Endangered closely related species (a phenomenon Species Act requires the protection of biologists call adaptive radiation). The adequate habitat for a listed species to genus Heteropsis is represented by ap- recover, providing the potential for proximately sixty species on the island, these species to serve as umbrellas. The and the genus Strabena by fifty species. problem is that this umbrella concept The satyrines have the misfortune of doesn’t always work to protect those being small, brown, and quite difficult WINGS Satyrine butterflies have been important in planning new parks on Madagascar. Unlike many species on that island, satyrines may ap- pear drab at first glance; looked at more closely they are really quite beautiful. Strabena argyrina, photographed by David Lees. to identify to species. Although many with many other colleagues, helped the people do not consider these butterflies Malagasy government achieve an even attractive enough to be worthy of at- more ambitious target, identifying pri- tention, they are actually very beautiful ority areas to triple the size of the pro- on close inspection. Not surprisingly, tected area network to cover 10 percent this difficult group was poorly known of the entire island. Along with the data even by entomologists, and, working on plants and vertebrates that are typi- with my colleague David Lees of Lon- cally employed, we assembled informa- don’s Natural History Museum, I found tion on ants and butterflies to use in de- many new species. In addition, we con- veloping the plan. Our study (published sistently found this group of butterflies in the international journal Science in to be highly informative for conserva- 2008) conclusively demonstrated that it tion priorities. It’s quite unlikely that is essential to include multiple indica- the public would ever accept building tor groups in order to develop effective a conservation plan based solely on conservation plans for biodiversity. Pro- these dun-colored insects, but we used tecting the lemurs would not provide data on this group, along with data on a good outcome for the ants, and vice lemurs, birds, small mammals, and versa. This finding echoed earlier work tiger beetles, to design Madagascar’s by Craig Moritz in the wet forests of largest park, in the remote rain forest Australia, which showed that data on of the Masoala Peninsula. Just recently, insects provided far greater spatial reso- Dimby Razafimpahanana, Alison Cam- lution for conservation planning than eron, Tom Allnutt, and myself, along did vertebrate data. FALL 2009 California’s Central Valley is dominated by agriculture, with habitat restricted to the surrounding hills and riparian areas. As part of the effort to re-wild parts of the land- scape in the agricultural areas, hedgerows have been planted for wildlife. Photograph by John Anderson, courtesy of Hedgerow Farms. Taking another tack in California’s row-to-fencerow farmed lands to bring Central Valley, an agricultural region back the quail, pheasants, and rabbits. that produces a quarter of the United Others are pursuing compliance with States’ fruits and vegetables, I am on a California’s water-quality legislation campaign to re-wild the monocultures and recognize that vegetated waterways that now blanket this huge expanse. will filter out the fertilizers and pesti- Through restoration of native plant cides that have become so ubiquitous hedgerows, the goal is to bring back in today’s agriculture. some of the ecological services, such Relatively few growers, however, as pollination and pest control, that are drawn to plant hedgerows simply natural habitat used to provide within because hedgerows may increase pop- agro-ecosystems. Many growers are re- ulations of beneficial insects that sup- ceptive to the hedgerow concept, but press pests or pollinate their crops. So for varying reasons. For some, it’s be- we piggyback this concept onto water cause they like to hunt, and they need filtration and management, aesthetic to restore some habitat on their fence- beauty, windbreaks, and hunting. Cur- WINGS rently, in a long-term project in nearby gardens and “victory gardens,” organic Yolo County, California, my laboratory produce, and community-supported group at the University of California at agriculture, as well as in diversified Berkeley is painstakingly document- farming systems, suggests that people ing the economic benefits to growers of are starting to appreciate and even de- planting hedgerows, through reduced mand more sustainable forms of agri- need to use insecticides for pest control culture.