Essays on Invertebrate Conservation

WINGS ESSAYS ON INVERTEBRATE CONSERVATION

THE XERCES SOCIETY SPRING 2011 CONTENTS

Introduction Scott Hoffman Black Page 3.

Endangered Crab Found in West Africa’s Shrinking Forests Neil Cumberlidge and Piotr Naskrecki We think of crabs as marine animals, but across the tropics they have adapted to live in fresh water and on land. One species, Guinea’s purple marsh crab, was an enigma until its recent rediscovery. Page 4.

Aliens Douglas Tallamy The use of non-native plants in the landscape may lead to declines in populations of native insects that co-evolved with particular species of native plants. Page 9.

Milkweeds: Not Just for Monarchs Brianna Borders and Matthew Shepherd Although milkweed plants are seen in many places—farms, ranches, roadsides—as a problem to be eradicated, they support a diverse community of insects. Page 14.

Six-Legged Tigers David L. Pearson Tiger beetles, with their bright colors and constant activity, have become a popular subject for hobbyists, who are adding to our knowledge of these insects. Page 19.

Watching the Devil’s Horses Pass By Celeste Mazzacano Dragonflies, fragile as they may appear, can fly thousands of miles. Eighteen species in North America are known to migrate with the seasons. Page 24.

Xerces News A remembrance of Thomas Eisner, an extraordinary scientist and a former presi- dent of the Xerces Society; petitioning for the protection of five endangered cold- water-dependent insect species; efforts to protect North America’s ailing bumble bee populations; and advocating for Fender’s blue butterfly. Page 29.

 WINGS Introduction

Scott Hoffman Black

In looking at the cover of this issue of We also have three articles about in- Wings you might have noticed some- vertebrates that do not directly rely on thing different: a photograph of a plant plants. The purple marsh crab, living in rather than the customary invertebrate. West Africa, was rediscovered sixty years Plants and insects are inextricably after the first—and only—specimen was linked; two essays in this issue explore collected. An essay about tiger beetles this interaction. The first underscores shows that not only are they amazing the importance of native plants to the creatures in beauty and behavior, but native insects that feed on them. The they are useful in helping us to under- presence of non-native plants can sig- stand and manage the habitats in which nificantly reduce the abundance of na- they live. The last article delves into the tive insects, which in turn impacts the little-known world of migratory dragon- songbirds and other animals that eat flies—some of which travel further than them. The second looks at the astound- monarch butterflies—and discusses the ing array of insects that use milkweeds, newly formed Migratory Dragonfly Part- and the ways in which the Xerces Soci- nership, which is working to understand ety and its partners are working to re- and protect these animals. turn milkweed to our landscapes and in- We hope you find this selection of crease local supplies of milkweed seed. essays informative and enjoyable.

This hickory horned devil will develop into a regal moth, Citheronia regalis, but only if it has adequate native plants to eat. Photograph by Douglas Tallamy.

SPRING 2011  Endangered Crab Found In West Africa’s Shrinking Forests

Neil Cumberlidge and Piotr Naskrecki

We were camped in West Africa, on the ubiquity in tropical aquatic ecosystems, westernmost fringe of the Upper Guinea the thirteen hundred or so species of forest, a vast area stretching from Guin- freshwater crabs have somehow avoided ea to Sierra Leone and Liberia. As part the full attention of the scientific com- of an international team of scientists munity. Interest in their biology and conducting a rapid assessment of this conservation is only now beginning to historically biodiversity-rich region, we gain momentum. had come to survey invertebrates, par- The success of the world’s marine ticularly freshwater crabs. At first sight land crabs — species that live in man- these damaged forests and parched sa- grove forests, on beaches, or further in- vannas, degraded by agriculture and land, but still need to return to the sea to industry, seemed an unlikely place to breed—in the coastal fringes throughout seek rare aquatic animals. But we were the tropics is due to their well-developed there because of the imminent threat of abilities to breathe air, dig burrows, de- further industrial expansion and addi- hydrate slowly, and walk easily on land. tional ecosystem disruption. These adaptations gave access to new Our campsite was in disturbed food sources and living spaces in the land under intense agricultural man- coastal lands above the high-tide line, agement in northwest Guinea, but by and this is where these animals now sheer luck our tents were pitched just a reign supreme. few kilometers from a thriving colony Freshwater crabs evolved from ma- of some of the continent’s most elu- rine crabs, but succeeded in breaking sive crustaceans —purple marsh crabs the connection to salt water with ad- (Af­rithelphusa monodosa). This species aptations that enabled them to osmo- is truly an enigma, previously known regulate in low-salinity environments. only from a single specimen collected in These included ion pumps on their gills 1947. Yet, amazingly, just a day after we that move salts inward, antennal glands began our survey, a local farmer walked (kidney-like organs) that pump water right into our camp holding one! out of their blood, and an impressively Purple marsh crabs belong to a di- waterproof carapace. As a result, fresh- verse group of decapod crustaceans col- water crabs complete their life cycle in loquially known as river crabs or fresh- fresh water and never need to return to water crabs, which are abundant in sea water to breed. the rivers, streams, and lakes of inland Our newly rediscovered Guinean waters throughout the tropics. Despite species was among the small subgroup their large size, attractive colors, and of the freshwater crabs that we call fresh­

 WINGS water land crabs, those species that can in water only as a last resort, usually to live and reproduce well away from per- avoid predators, and seem uninterested manent water sources. in using oxygen from water. Structural modifications in their The abilities of the freshwater land gill chambers enable many species of crabs to breathe air, dig burrows, resist freshwater crabs to breathe in air as well drying, and walk on land easily match as underwater. Their gill chambers are those of marine land crabs. Freshwater so well adapted for aerial respiration that crabs have a reproductive adaptation their ability to breathe is undiminished that opened up to them vast tracts of by being out of water. The bottom layer land in the inland tropical ecosystems of each gill chamber has the usual set of of the world’s continents that even the gills that are seen in most crabs, which well-adapted marine land crabs had not allow them to breathe under water. But conquered. In contrast to marine crabs, it is in the upper layer above the gills which release their eggs into sea water where the truly remarkable adaptation and whose larvae spend several weeks in is found. Here there is a spongy air- an un-crablike, planktonic stage floating breathing organ, which is analogous to with the currents, larval development a vertebrate lung in function but struc- in freshwater crabs is completed entirely turally so different that it is known as a inside the egg case, with each egg releas- “pseudolung.” ing a fully formed miniature crab. The In purple marsh crabs, this respira- evolution of larval direct development tory structure works so well that they ac- has had big ecological consequences for tually prefer to breathe air rather than freshwater crabs. For one thing, it meant water. These crabs immerse themselves that these crustaceans could complete

Land crabs have adapted to life away from water, but most still need to return to breed. Blue land crab (Cardisoma guanhumi), at water’s edge, waiting to release her eggs. Photograph by Piotr Naskrecki.

SPRING 2011  their entire life cycle in their inland humid rainforests, further adaptations habitat, using fresh water for all of their such as small compact bodies and long needs. And it released female freshwater slender walking legs have enabled fresh- crabs from the need to spend valuable water crabs to move easily through veg- energy making migrations to the coast etation and even to climb tree trunks, during the breeding season. This radi- thereby equaling or surpassing the feats cal adaptation removed one of the last of most marine land crabs. barriers to the colonization of land and Marine land crabs found in coastal gave them total independence from salt- Guinea, such as the rainbow crab (Cardi­ water environments, which in turn led soma armata), and air-breathing man- to the explosive radiation of freshwater grove crabs, such as the fiddler crab crabs in the inland waters of the tropics Uca tangeri, each are widely distributed around the world. along hundreds of miles of the West Today, these crabs are dominant African coast from Senegal to Angola. inhabitants of warm fresh waters from These wide distributions are a direct tropical America to Australasia. Fresh- consequence of their developmental water crabs have conquered not only strategy, in that the currents carry the more conventional freshwater ecosys- larvae long distances from their release tems such as rivers and lakes, but some points during the weeks spent drifting species, including the purple marsh in the surface waters. In contrast, most crab, have colonized such marginal freshwater crabs have a narrow distri- habitats as flood plains bordering riv- butional range — except perhaps where ers and streams, damp terrain in fresh- a major river system is involved. The water swamps and marshes, and dried- lack of larval stages means that fresh- out river beds in parched savannas. In water crab hatchlings do not stray far

The purple marsh crab (Afrithelphusa monodosa) was recently rediscovered in West Africa by the authors. Photograph by Piotr Naskrecki.

 WINGS Purple marsh crabs live in swampy areas, which are increasingly under cultivation. Photograph by Piotr Naskrecki. from the place where they were born, in the colder nocturnal air, scavenging and only adult crabs disperse any dis- the nearby land for vegetable matter or tance; as a consequence, speciation is the remains of plants and animals. The common and endemism is high. The first storms of the wet season inundate smallest distributional ranges of all are the burrows and prompt the crabs to seen in those species of freshwater land crawl onto land in the daylight hours, as crabs that live in marginal habitats in well as the night. On the surface the air isolated mountain streams, rainforests, is cooler and more humid, and the new swamps, marshes, and dry savannas far undergrowth provides both conceal- away from major aquatic systems. ment from predators and shade from Once back home in our laboratories, the sun. As the rains continue, exten- we used DNA analysis to confirm that sive wetlands develop and crabs congre- the purple marsh crab indeed belongs gate in the muddy, shallow waters of the to the African family Potamonautidae, newly formed pools and marshes. and learned that it lies on an evolution- The secretive purple marsh crab of ary branch separate from most fresh­ Guinea seems to lead a burrow-bound water crab species in that continent. We life in perennially marshy ground, a spe- also described the habitat requirements cialized niche that limits its population and behavior of this species for the first density and distributional range. Its in- time: it prefers marshy wetlands, many clusion as an endangered species on the of which are now moist farmland on Red List of Threatened Species by the which bananas, pineapples, and cas- International Union for Conservation sava are grown. There crabs live under- of Nature (IUCN) shows that its long- ground in burrows partially filled with term survival is at risk. Indeed, it may be shallow, oxygen-depleted fresh water, making its last stand in that small area easily overcoming any oxygen short- of Guinean farmland, and the chances ages by switching from water breathing of this fragile species’ survival are slim to air breathing. During the long dry if its wetland habitat continues to be de- season crabs emerge from their burrows stroyed at the present rate.

SPRING 2011  Freshwater crabs have long legs and small bodies that make it easy for them to move through vegetation or climb trees. Sylviocarcinus pictus, photographed by Piotr Naskrecki.

Our chance rediscovery of the pur- Dr. Neil Cumberlidge is a prof­essor in the ple marsh crab gave us an opportunity to biology department at Northern Michigan observe and learn about a little-known University, Marquette, where he works on species from a fascinating lineage of the taxonomy, systematics, phylogeny, terrestrial crustaceans. Freshwater land evolution, biogeography, and conservation crabs such as A. monodosa and its red-list- of­ Af­rican and Madagascan f­reshwater ed relatives in Guinea, Sierra Leone, and crabs. He is chair of­ the Species Survival Liberia live in the increasingly disturbed Commission’s Freshwater Crabs and Cray­ habitats of West Africa’s Upper Guinea fish Specialist Group f­o the IUCN. forest ecosystem—a biodiversity hotspot Dr. Piotr Naskrecki is a research asso­ with an incredible richness of endemic ciate at the Museum of­ Comparative Zool­ plants and animals that makes it one of ogy, Harvard University, where he works on the world’s priority conservation areas. the evolution and systematics of­ orthop­ Time is running short for that remark- terid insects. He is also involved in a num­ able ecosystem and many of its unique ber of­ invertebrate conservation projects, species of flora and fauna—including its including the IUCN Red List assessment rare and barely studied freshwater land of­ Af­rican katydids and the development crabs—could be threatened with extinc- of­ internet-based resources f­or invertebrate tion. Unfortunately, should we return to biologists and conservation practioners. the Upper Guinea forest, our campsite The authors thank Conservation Inter­ is increasingly less likely to be so fortu- national f­or the opportunity to once again itously located. get close to Af­rica’s f­reshwater crabs.

 WINGS Aliens

Douglas Tallamy

Although I chose entomology as a pro- plants and insects. These were the class- fession, I understand the thrill of grow- es that explained why most insect her- ing exotic plants. In graduate school, I bivores can eat only plants with which took a class in woody landscape plants they share an evolutionary history. All from the noted horticulturist Robert of the information I needed to realize Baker. I left that course with an intense that covering the land with alien plant desire to plant as many of the species I species might not be such a good idea had just learned about as possible. The had been neatly and simultaneously only thing that slowed me down was placed in my lap during those months in that, as an apartment dweller, I had no graduate school, but it was twenty years place to plant them. Still, I gathered before I made the connection: the vast seeds from many of the ornamentals on majority of our native insects cannot campus, germinated them in the green- use plant species that evolved outside of house, and planted the seedlings all over their local food webs. the yards of my parents and relatives. In 2000 my wife and I moved to I now find it ironic that, at the same ten acres in Pennsylvania. The area had time that Professor Baker was turning been farmed for centuries, before being me on to alien ornamentals, I was tak- subdivided and sold to people like us ing courses about interactions between who wanted a quiet rural setting close

Native trees —particularly oak, maple, and willow— are re- quired food for caterpillars of the polyphemus moth (Anther­ aea polyphemus). Photograph by Douglas Tallamy.

SPRING 2011  to work. We got the rural setting we then insect populations in areas with sought, but it was not the slice of nature many introduced plants will be smaller we had hoped for. At least 35 percent than those in areas with all natives. Be- of the vegetation on our property (yes, cause so many animals depend partially I measured it) consisted of aggressive or entirely on insect protein for food, a plant species from other continents. We land with fewer insects is a land with quickly agreed to make it a family goal fewer forms of higher life. Birds would to rid the property of alien plants and suffer most, because 96 percent of our to replace them with species that had terrestrial bird species rear their young evolved within the eastern deciduous on insects. forests. Ecologists suggest three reasons Early on in my assault on the aliens why most native insects do not eat in- in our yard, I noticed a rather striking troduced plants. First, many of the inva- pattern. The alien plants that had taken sive plants that have succeeded in North over our land—multiflora rose, autumn America were imported specifically be- olive, privet, oriental bittersweet, Japa- cause of their unpalatability to insects. nese honeysuckle, Amur honeysuckle, As Michael Dirr repeatedly emphasizes Bradford pear, Norway maple —all had in his acclaimed books on ornamental very little or no insect-caused leaf dam- plants, species that are “pest free” are fa- age, while the red maples, black and pin vored by the ornamental industry. Un- oaks, black cherries, black gums, black fortunately, 85 percent of the invasive walnuts, and black willows had obvious- woody plant species in the United States ly been eaten by many insects. This was are escapees from our gardens! alarming, because it suggested a conse- The second reason is that it takes quence of the alien invasion occurring time —long evolutionary time spans, all over North America that was under rather than short ecological periods — the radar. If our native insect fauna can- for most insects to adapt to the specific not, or will not, use alien plants for food, chemical mix that characterizes dif-

Like most songbirds, the white-eyed vireo (Vireo griseus) rears its young on insects. Photograph by Douglas Tallamy.

10 WINGS ferent plants. The literature is replete with evidence that the number of in- sect herbivores associated with trans- planted aliens is only a small fraction of the number associated with these plants at home. In Europe, for example, Phragmites (the common reed) supports more than 170 species of phytophagous insects, while only five species of our native herbivores feed on this plant in North America. Similarly, since the in- troduction of melaleuca to Florida in the early 1900s, only eight species of arthropods have been recorded eating the leaves of this Australian native; in its home region, 409 species are known to eat it. Similarly, Eucalyptus stellulata, an introduced tree touted as supplying nectar for bees in California, supports forty-eight species of insect herbivores Banded tussock moth (Halysidota tessel­ in Australia, but only one native insect laris) caterpillars feed on a range of native herbivore in California. These examples trees from July to October. Photograph by demonstrate that adaptation to non-na- Douglas Tallamy. tive plants by our native insects occurs, but is a slow process indeed. have been working to fill this gap in our The third reason that native insects knowledge. One of the first things we shun aliens is that most phytophagous did was to compile information about insects feed on plants with which they Lepidoptera larvae collected from every share an evolutionary history. Leaders plant genus—all 1,385 of them—in the in the field of plant/insect interactions mid-Atlantic states. We focused on Lepi- such as Dan Janzen, Doug Futuyma, doptera because host records for moths Fred Gould, and Elizabeth Bernays have and butterflies are far more complete all estimated that 90 percent of phy- than those for other types of insect her- tophagous insects have evolved associa- bivores, and because caterpillars are dis- tions with no more than a few plant lin- proportionately important food sources eages. (It is important to highlight that for birds. Two years and more than four these predictions focus on how insect hundred references later, we were able herbivores use plants. They are not pre- to rank mid-Atlantic plant genera, both dictions about pollinators, parasitoids, natives and naturalized aliens, in terms or predators that visit flowers for nectar of their ability to support the larvae of or pollen.) 2,909 Lepidoptera species. How do we know the actual extent We learned much from this effort. to which our native insects are eating Even among natives there is tremendous introduced plants? My students and I variation in the ability to support cater-

SPRING 2011 11 reduce the abundance and diversity of both generalist and specialist Lepidop- tera. Alien plants that are congeners — close relatives — of a common native species reduced Lepidoptera communi- ties by 50 percent, while an alien plant that is not closely related to any local species reduced Lepidoptera abundance and diversity on average by 75 percent! We know that most bird populations are limited by the amount of food they can find, so if there are dramatically fewer caterpillars in neighborhoods dominat- ed by introduced ornamentals, it is no wonder that our birds are struggling. The spun glass moth (Isochaetes beuten­ Many people justify the use of an muelleri) caterpillar is a specialist of oaks. introduced ornamental — or inaction Photograph by Douglas Tallamy. against an invasive alien—by contend- ing that it supports a particular butter­ pillars. Oaks supported the most species fly, beetle, or bee. This approach, how- (534), followed by native cherries (456), ever, considers what is gained from a willows (455), and birches (413), while plant without considering what is lost there were some natives, such as sweet- through its presence. Kudzu provides an spire (Itea) and yellowwood (Cladastris), excellent example. When an acre in Vir- on which no Lepidoptera were recorded. ginia is overrun with kudzu, the silver- As predicted, favorite landscape plants spotted skipper (Epargyreus clarus) can that evolved elsewhere such as forsyth- still find larval food because it is able to ia, golden raintree, Zelkova, and Meta­ add kudzu to its list of leguminous host sequoia, supported few or no caterpillar plants. But the meadow fritillary (Bolo­ species. All members of the thirty-eight ria bellona), variegated fritillary (Eupto­ most productive genera were native to ieta claudia), and great spangled fritillary the mid-Atlantic region, with the ex- (Speyeria cybele) would no longer be able ception of pear (Pyrus), an agricultural to reproduce in that field because their genus. Among ornamental plants, na- violet host plants are lost. Similarly, tives supported on average seventy-four monarch butterflies (Danaus plexippus) species of native Lepidoptera, while would lose their milkweed host plants, aliens supported fewer than five —just as the two hundred or more species of one-fifteenth as many. moths that feed on goldenrod and as- These results have been supported ters would lose theirs. Trees are not im- by a large study in which we compared mune to kudzu, and the oaks, cherries, how well introduced plants support na- and willows that each support four or tive insects. In a replicated common five hundred species of moths and but- garden experiment, my students and I terflies would be smothered. Many more showed that alien plants significantly genera of native plants would be elimi-

12 WINGS nated on that acre, as would the hun- By favoring native plants over aliens dreds of insect species they support. in the suburban landscape and by work- We needn’t limit this discussion to ing to minimize the abundance of inva- invasive species. We have replaced di- sive plants in our natural areas, we can verse native plant communities in thou- do much to sustain the biodiversity that sands of square miles of suburbia with has been one of this country’s richest as- ornamental plants from Asia. Most of sets. Native plants support and produce these plants are not currently invasive, more insects than alien plants do, and yet if planted everywhere they have a therefore more numbers and species of similar impact on insect herbivores. other animals. Somehow we have come Imagine a neighborhood in which na- to expect an artificial perfection in our tive pines are replaced by Deodar cedars gardens and the greater landscape: the from the Himalayas. The pine white plastic quality of flowers is now seen as butterfly Neophasia( menapia) is able to normal and healthy. It is neither. In- develop on Deodar cedars, but more stead, it is a clear sign of a garden that is than two hundred other species of pine no longer a living community; a garden specialists would lose their host plants. in which any life form other than the desired plants is viewed as an enemy and quickly eliminated. In essence, we have demoted plants to mere decorations in our unnatural landscapes. To sustain biodiversity we will ulti- mately need to improve the complexity and stability of insect-based food webs, both in our yards and in local natural areas. Although some insects can meet their needs with introduced plants, most cannot. This illustrates the real costs associated with replacing native plant communities with alien plants but also suggests ways to reverse the losses in biodiversity that have characterized our times.

Doug Tallamy is a prof­essor and the chair of­ the Department of­ Entomology and Wildlif­e Ecology and director of­ the Cen­ ter f­or Managed Ecosystems at the Uni­ versity of­ Delaware in Newark, where he has taught courses f­or thirty years and au­ Great spangled fritillaries (Speyeria cybele) nectar on many flowers, but their caterpil- thored seventy-three research articles. This lars eat only violets. Photograph by Doug- essay was adapted f­rom his book Bringing las Tallamy. Nature Home.

SPRING 2011 13 Milkweeds: Not Just for Monarchs

Brianna Borders and Matthew Shepherd

Standing in a field of milkweed plants, animals. If eaten by livestock, milkweed John Anderson watches a monarch but- typically causes depression or diarrhea, terfly search for a place to lay her eggs. although it may be fatal. Fortunately, This sight epitomizes most people’s milkweed is bitter in flavor and unpal- image of milkweed: food for monarch atable, and range animals will gener- caterpillars. This, however, is no ordi- ally avoid eating it if sufficient forage nary field of milkweed, and John is not is available; most milkweed poisoning most people. The co-owner of Hedge- results from hungry animals being con- row Farms near Winters, California, centrated in areas where milkweed is John is at the forefront of a movement abundant. to encourage the use of locally native The toxin-laden sap deters mam- milkweed in restoration projects. As the mals, but insects have an amazing capac- obligate host plants for monarch cater- ity to overcome the chemical defenses pillars, milkweeds play a vital role in the of plants, particularly those with which life cycle of the monarch butterfly (Da­ they have a shared evolution. In fact, a naus plexippus). They also provide food large number of insects eat milkweeds, or shelter for a diverse array of other often harvesting the toxins for use in insects, including nectar-seeking bees, their own defense; of the insects that flies, and butterflies, and such specialist do this, monarchs are the best known. herbivores as seed bugs, longhorn bee- Their caterpillars sequester the toxins tles, and leaf beetles. Native milkweeds and store them in their tissues, giving are clearly worthy of wider adoption. them a bitter taste. They have boldly More than a hundred species of colorful warning— ­aposematic—mark- milkweeds (Asclepias) are native to ings, which serve as a reminder to birds North America and they can be found and other predators. Other milkweed- in deserts, plains, valleys, foothills, feeding insects, including milkweed open woods, and wetlands. Milkweeds bugs, milkweed longhorn beetles, and also grow in disturbed environments in- milkweed leaf beetles, sequester and cluding agricultural areas, livestock pas- store the milkweeds’ toxic chemicals to tures, ditches, and roadsides; indeed, in aid their own defense, and like monarch some areas, these marginal habitats are caterpillars, generally have aposematic the only places where milkweed is regu- markings. larly seen. Large milkweed bugs (Oncopeltus Milkweed is named for its milky spp.) feed only on milkweeds and closely latex sap, which oozes from damaged related plants. Although these bugs will leaves and stems. This sap contains feed on young leaves, flowers, and devel- alkaloids and cardenolides, complex oping pods, a seed diet provides for op- chemicals that make the plants toxic to timal growth and reproduction, and for

14 WINGS this reason adults lay their eggs close to tion. Milkweed pollen does not occur as developing pods. Small milkweed bugs free grains, but instead is contained in (Lygaeus spp.) feed on seeds as nymphs pairs of waxy sacs —pollinia—that are but they can develop on plants other located within vertical grooves on the than milkweeds. As adults, they are not flowers, called stigmatic slits. Each pol- strictly herbivorous, and will scavenge linium contains several hundred grains insects trapped in milkweed flowers, of pollen. An insect that visits a flower feed on monarch butterfly pupae, and to obtain nectar may leave with a pair even engage in cannibalism. of pollinia affixed, the result of coming Milkweed longhorn beetles (Tetra­ into contact with a corpusculum, a pol- opes spp.), so-named for their prominent linia-bearing gland located at the top of antennae, feed exclusively on milk- a stigmatic slit. (Insects may accumulate weeds and close relatives. They are gen- strings of corpuscula and pollinia from erally host-specific—there are thirteen repeated flower visits. In Robert Wood- species of milkweed longhorn beetles son’s extensive monograph on the As­ in the United States and each prefers a clepias species of North America, he re- different species of milkweed. ported an instance of a single honey bee The milkweed leaf beetle (Labi­ carrying forty-five corpuscula!) Pollinia domera clivicollis) overcomes milkweed’s most commonly become attached to an defenses by biting through veins of the insect’s legs but they can also be borne leaf. The sap drains from the outer part, on the mouthparts or on any barbed or and the beetle can feed in relative safety hairy surface of an insect’s body. Fertil- on the drained area beyond the cuts. ization occurs when pollinia are trans- The relationship between milk- ferred by the insect into the stigmatic weeds and insects is not one-sided. Milk- slits of another milkweed flower. weeds are entomophilous, meaning that Although milkweeds have a very they depend on insects for their pollina- specialized pollination mechanism,

Bright markings warn predators that the large milk- weed bug (Oncopeltus fasciatus) tastes bad. Photograph by Bryan E. Reynolds.

SPRING 2011 15 they do not require specialist insects ington State University, milkweed—in to activate it. Any insect that is large this case, showy milkweed (Asclepias enough to remove and transport pol- speciosa)—attracted the highest number linia can be an effective pollinator, and of beneficial insects of any of the forty- milkweeds are pollinated by a broad three species of native flowers being range of bees, wasps, butterflies, flies, studied. and beetles, even true bugs. A review of Insects whose adults visit milk- milkweed pollination studies completed weeds for nectar include ichneumon, by Jeff Ollerton and Sigrid Leide revealed braconid, and mymarid wasps, all of that whorled milkweed (A. verticillata) which are parasitoids (meaning that has 126 documented pollinators. they lay eggs on or in a host insect; once With their pollen enclosed within hatched, their offspring then consume pollinia and inaccessible, milkweeds the host), and thus natural predators of have only nectar with which to reward crop or garden pests. The closely related visitors. Even so, they attract a tremen- ichneumon and braconid wasps typi- dous variety of insects with the abun- cally parasitize aphids or the soft-bodied dant, high-quality nectar that is readily larvae of such insects as butterflies, flies, accessible in the hoods of their flowers. and beetles, while mymarid wasps para- Many of the nectar-seeking insects in- sitize insect eggs. Syrphid flies are also advertently end up as pollinators, while attracted to milkweeds: the adults drink others bring benefits in other ways. In the nectar and their highly mobile lar- a recent study by David James of Wash- vae prey directly on aphids.

Milkweeds support a diverse community of insects that visit to drink nectar or feed on the plant itself— or on the other visitors. Photograph by Bryan E. Reynolds.

16 WINGS Fewer milkweed plants for its caterpillars to eat is one reason for declines in monarch butterfly (Danaus plexippus) popula- tions. Photograph by Bryan E. Reynolds.

One conspicuous insect that can fre- archs. Each spring, the butterflies leave quently be seen nectaring on milkweed the groves in search of milkweed on in California and the desert Southwest which to lay their eggs. Over the sum- is the tarantula hawk wasp (Pepsis spp.). mer, successive generations spread out As their name suggests, these wasps across North America west and south of hunt tarantulas, not for themselves—as the Rocky Mountains and as far north adults they eat only nectar—but to sup- as British Columbia, with the last gen- ply the nests of their offspring. eration making the journey back to the Like many native plant species, California coast. Unfortunately, western milkweed populations are being lost at monarchs are in trouble. Data collected a rapid rate due to urban and suburban by volunteers show that the number of development and agricultural inten- overwintering monarchs has dropped sification. Despite their native status, by more than 90 percent since 1997. unique beauty, and value to the mon- In 2008 the Commission for En- arch butterfly as well as to a tremendous vironmental Cooperation (a treaty range of pollinators and other beneficial organization of the United States, insects, milkweeds are often perceived Canada, and Mexico) published the as crop weeds or a threat to livestock North American Monarch Conservation and eradicated from agricultural areas, Plan, addressing the steady decline of rangelands, and roadsides. the butterflies across their native range Loss of milkweeds is believed to be since population monitoring first began one of the factors (along with distur- in 1976. Because of their migratory life- bance to and destruction of overwinter- cycle (breeding in the United States and ing sites) that have led to the steep de- Canada, overwintering in Mexico and cline of the western population of mon- California), the most effective conser- archs. The butterflies spend the winter vation strategies for monarchs are those months in tree groves along the coast that protect and restore habitat across of California, the only U.S. state with their entire range. The plan cites broad large numbers of overwintering mon- national declines in milkweeds and

SPRING 2011 17 Butterfly weed (Asclepias tuberosa) has a wide distribution, but is not always the most appropriate milkweed for habitat projects. Photograph by Allen Casey. recommends the planting of regionally appropriate native milkweed seed, and appropriate native milkweed species to working with the NRCS to incorporate offset the loss and degradation of mon- milkweeds into the agency’s pollinator- arch breeding habitat. habitat restoration projects. Unfortunately, few commercial As part of this effort, John Anderson sources of native milkweed seed cur- has already produced seventy pounds of rently exist across the monarch’s spring seed from narrow-leaved milkweed (A. breeding range in the United States — f­ascicularis), which can be used in resto- California, the Southwest, Texas, and ration across California. We hope that Florida — and, in these places, either this is just the first batch of milkweed no milkweeds are planted or those that seed that will be planted to help stem are planted are species from outside of the downward spiral of monarch but- the region. Clearly, there is a need for terflies, while at the same time sustain- sources of locally native milkweed seed. ing the richness of insects required for a In 2010, with support from the Monarch healthy environment. Joint Venture and a Conservation In- novation Grant from the USDA Natural Resources Conservation Service (NRCS), Brianna Borders is a plant ecologist who the Xerces Society launched a multi- leads the Xerces Society’s ef­f­ort to increase state initiative to increase the availabili- the availability of­ milkweed seed. ty of native milkweed seed for monarch- Matthew Shepherd is a senior con­ habitat conservation efforts. Xerces is servation associate with Xerces. He has working with the native seed industry worked on pollinator conservation f­or a de­ to develop new sources of regionally cade and edits the Society’s publications.

18 WINGS Six-Legged Tigers

David L. Pearson

Tiger beetles are justifiably one of the tall termite mounds, where the beetles most popular and most studied beetle feast on larval glow worms that live in groups in the world. With about twenty- tunnels on the outside of the mounds. seven hundred species described so far, (At night, the glow worms cause the there could be as many as another two mounds to glow eerily in the darkness.) hundred species awaiting discovery. Even adults of the most widespread Tiger beetles occur in a wide variety species, such as the North American of biomes, from high-elevation alpine bronzed tiger beetle (Cicindela repanda), forests and high-latitude taiga (boreal) occupy relatively restricted habitats—in forests to tropical rain forests, from des- this case, sandy margins of rivers, lakes, ert washes to ocean beaches. They are and ponds. found in almost every part of the world Larvae of each species are even except Antarctica, Tasmania, and small- more restricted to microhabitats than er oceanic islands and atolls. are their adult stages. The larvae are No matter where they reside, how- also predatory, but they hunt using sit- ever, each species tends to occupy a nar- and-wait techniques from the mouths row or highly specialized habitat. For ex- of vertical tunnels in the soil. Some of ample, in the Gran Chaco region of Bra- these tunnels reach more than six feet zil, Paraguay, Bolivia, and Argentina, the (two meters) in depth, but most are only bicolored mound-dwelling tiger beetle six to twelve inches (fifteen to thirty (Cheilonycha auripennis) occurs only on centimeters) deep. The larvae of some

Tiger beetles are alert, fast-running hunters. Big sand tiger beetle (Cicindela formosa), photographed by Bryan E. Reynolds.

SPRING 2011 19 tropical arboreal species construct their ity and reliably find most of the species tunnels in decaying wood. within a short time, even in such com- Although adults of many species plex and species-rich habitats as tropi- are plain in appearance, with browns cal forests. At one site at Tambopata in and blacks predominating, many are as southeastern Peru, ornithologists took colorful as spectacular jewels—emerald almost five years of intensive work to green, purple, orange, and eye-popping document 90 percent of the bird spe- crimson. Upon closer inspection, even cies occurring there, while in the same the apparently plainly colored ones are area butterfly and dragonfly workers pointilistically covered with brightly took two or three years to arrive at this reflecting microscopic pits. The various level of knowledge for their respective colored reflections from these pits blend taxa; those of us looking for tiger beetles through the physics of interference to found 90 percent of the fauna within the produce the subdued but still attractive first fifty-five hours of searching. hues that are seen with the naked eye. Field identification guides for tiger Adult tiger beetles can fly short dis- beetles have been published for many tances to escape danger. They spend countries, including Bolivia, Venezuela, most of their time on the ground and Colombia, Thailand, and Madagascar, among rocks, although a few tropical and these publications have encouraged species patrol tree trunks and leaves. The amateurs in many countries to adopt beetles run rapidly on their long, thin tiger beetles as hobby organisms. The legs and use their large, sickle-shaped work of these enthusiasts quickly adds mandibles to capture and dismember to the growing body of information on small, fleeing arthropods. Hudson’s sa- tiger beetle distribution and natural his- line tiger beetle (Rivacindela hudsoni), tory in a cost-effective way. a flightless species found only on huge It is no wonder, then, that tiger saline lake beds in interior Australia, has beetles lend themselves well to con- been clocked running at 2.49 meters per servation efforts. Around the world second (5.57 miles per hour), so fast that they are among the few insect groups collectors can rarely get close to them. for which endangered species can be Largely because of the cooperative declared with certainty and placed on efforts between passionate amateurs national red lists. In the United States, and a few dedicated professionals over four species have been officially de- the past two centuries, the taxonomy of clared threatened or endangered by tiger beetles is relatively stable, even for the U.S. Fish and Wildlife Service, and species in such remote parts of the world some experts claim that as many as 15 as Sulawesi, Brazil, and the Sudan. These percent of the 225 named species and days, it is easier and faster for inexperi- subspecies in the United States and enced helpers and students to learn to Canada have fallen to such low levels reliably census tiger beetles than it is for that they should be considered for pro- them to learn to census other taxa. tection efforts. The Sacramento Valley And the work itself is faster: students tiger beetle (Cicindela hirticollis abrupta), of tiger beetles can quite easily census for instance, evidently has gone extinct an area during the season of adult activ- in the last thirty years, a victim of flood

20 WINGS The splendid tiger beetle (Cicindela splendida) displays spec- tacular iridescent colors. Photograph by Bryan E. Reynolds. control and habitat destruction. In Bo- that haunt conservationists who study livia, the beautiful Bolivian ornate tiger the many other taxa that are harder to beetle (Pometon bolivianus) was first dis- observe and easier to miss. By protecting covered and named in the early 1990s; threatened populations of tiger beetles although such a large and obvious spe- we also secure habitat for many other cies should be easy to find, it has not species that also need protection—an been seen since, even with extensive umbrella effect. searching in the same areas in which it We have strong evidence that, across was originally found (most of which are the world, the species richness of tiger now coffee plantations), and this species beetles is a good predictor of the spe- has been placed high on Bolivia’s red list cies richness of other, harder-to-census of endangered insect species. In Spain, taxa, such as butterflies and birds. And, the highly endemic Murcia tiger beetle because the number of species in a given (Cephalota deserticoloides) has been de- locale can be so quickly determined, we clared endangered. In Sweden, the most can census hundreds of acres for tiger northern populations of the wide-rang- beetles in the time it would take to cen- ing Eurasian tiger beetle (Cicindela mari­ sus one acre for birds or butterflies. tima) have been declared threatened due Tiger beetles thus make excel- to habitat destruction. lent bioindicators, and they have been Those of us working in conserva- used to monitor diversity in Amazonia tion cannot afford having to defend and other less-well-studied areas of the false claims of rarity, and the reliabil- world. With the aid of mathematical ity of accurately censusing tiger beetles modeling we can examine a wide swath minimizes questions of detectability of habitat and generate broad estimates

SPRING 2011 21 Many tiger beetles have obvious markings, easing their identification. Oblique-lined tiger beetle Cicindela( tran­ quebarica), photographed by Bryan E. Reynolds. of the quantitative patterns of tiger bee- can even help to guide management de- tle species across vast areas such as the cisions. In Venezuela, for example, con- Indian subcontinent or South America. servation advocates have joined with These patterns reveal areas of high and lumber companies to maintain forest low species richness, which in turn can biodiversity while increasing profits, help determine priorities and boundar- applying their knowledge of the habitat ies for protected areas, as, for instance, specialization of the local tiger beetles in the case of Madagascar’s recently de- in planning a long-term rotation for clared Masoala National Park. harvesting smaller plots within a large Bioindicators also have a role to play forest concession. Although timing log- in the early detection of habitat degra- ging to maintain the forest for sustain- dation. Because tiger beetle adults and able use is made difficult by local varia- larvae are so specialized in habitat use, tions in drainage, soil fertility, and a host they tend to be highly sensitive to minor of other factors that render dependence changes, functioning as barometers of on a rigid timetable impossible, the pres- degradation that might imperil them ence of particular species of tiger beetles and their habitats. Collections made provides a relatively accurate measure of long ago are valuable aids in comparing when the forest is sufficiently mature for the historic distributions of tiger beetle harvest. Succeeding patches of regener- species with their current geographic ated forest, from cleared to mature, have ranges; tiger beetle records accumulated different tiger beetle species present, over the last century and a half in Eu- each adapted to differences in shade rope have already documented habitat tolerance, temperature, and vegetation changes there that would not otherwise density. Now the companies monitor have been obvious. the presence of tiger beetles, and rehar- Tiger beetles, employed as bio­ vest particular sections only when the indicators to monitor habitat condition, complement of species is that known to

22 WINGS be typical of the mature forest commu- cisions and budget planning by profes- nity, thus maximizing the continuing sional biologists, politicians, legislators, complex diversity of the forest. and policy makers. This passion for tiger When Barry Knisley, Chuck Kazi­ beetles illuminates the ways in which lek, and I first published our Field Guide insects and their admirers can advance to the Tiger Beetles of­ the United States and conservation policy everywhere in our Canada in 2006, there were likely only a threatened world. hundred or so tiger beetle aficionados in North America, most of them amateurs. Now, just a few years later, we can hardly David L. Pearson, a research prof­essor in keep up with the flood of new distribu- the School of­ Lif­e Sciences at Arizona State tion records, natural-history observa- University, has worked with birds and tiger tions, and innovative insights into the beetles since he was a teenager in Minne­ study and uses of tiger beetles that we sota. His research has spanned habitats receive from thousands of enthusiasts. f­rom desert grasslands to tropical rain f­or­ With growing economies in China, ests, and he has co-authored eight books India, and much of South America, the ranging f­rom insect field guides to wildlif­e field guides and web sites that focus on guides f­or ecotourists. tiger beetles attract a growing number of For f­urther inf­ormation about tiger hobbyists who have the time and money beetles, see Tiger Beetles: the Evolution, to support their avocation. Ecology, and Diversity of the Cicindelids, The future of insect conservation by David L. Pearson and Alf­ried P. Vogler is more and more in the hands of these (Cornell University Press, 2001), and Ari­ professional amateurs, whose contribu- zona State University’s “Ask A Biologist” tions should help guide future policy de- web site.

Publication of excellent field guides has boosted interest in tiger beetles. Six-spotted tiger beetle (Cicindela sexguttata), photographed by Bryan E. Reynolds.

SPRING 2011 23 Watching the Devil’s Horses Pass By

Celeste Mazzacano

The sun is burning off the dawn mist morning sky. These birds are just a few as we jolt down a pot-holed road on of the participants in the Río de Rapaces the Caribbean coast of Mexico. Cows (River of Raptors), an annual migration gaze at us incuriously from wetland of five million birds of prey—more than pasture on the left, while malachite two dozen species —flying south over (Siproeta stelenes), yellow-fronted owl the state of Veracruz from late August to (Caligo telamonius), and postman (Heli­ mid-November. conius erato) butterflies are beginning It is not, however, the spectacle to fly through the forested hill rising to of eagles and hawks that has drawn us our right. Traveling with Doug Taron of here on this early-October day. Prona- the Peggy Notebaert Nature Museum in tura Veracruz has monitored this rap- Chicago, my destination this morning tor migration since 1991 and, in the is a raptor-banding station at Cansabur- course of their counting, they consis- ro operated by Pronatura, a nonprofit tently observe other annual migrants: organization dedicated to conserving darting swarms of thousands of drag- Mexico’s wildlife. Our companion on onflies, known locally as caballitos del this trip is Elisa Peresbarbosa Rojas, a Diablo —the Devil’s horses. These flights conservation assistant with Pronatura of dragonflies have also been observed Veracruz, who draws our attention to a at inland observatories in the cities of collection of hawks circling lazily in the Cardel and Chichicaxtle.

The wandering glider (Pantala flavescens) holds the record for the longest migration—more than eleven thousand miles—by an insect. Photograph by Netta Smith.

24 WINGS Large, colorful, and easy to identify, the common green darner (Anax junius) lends itself well to monitoring by citizen-scientists. Photograph by John C. Abbott.

Migrating dragonflies may be a ourselves eye-to-eye with a red-faced surprise to many people. The monarch dragonlet (Erythrodiplax f­usca) perched butterfly (Danaus plexippus) is the best- motionless on a leaf, its wings droop- known insect migrant, but the aptly ing forward in the characteristic pose named wandering glider (Pantala f­la­ of these small skimmers. A few com- vescens), a dragonfly found on every mon green darners (Anax junius) flash continent save Europe and Antarctica, by, followed by a tandem pair of red easily dethrones the monarch as the in- saddlebags (Tramea onusta) heading sect long-distance champion. In North south. Doug and I position ourselves America the wandering glider migrates in a small thatched blind, doing sets of along the East Coast, but it is its flight timed counts to estimate numbers of across the Indian Ocean that is the most passing dragonflies. For the first hour, remarkable. Riding the monsoon winds, our counts range from twenty-three the glider island hops from India to east to thirty-four dragonflies per three- and southern Africa; subsequent genera- minute interval—as many as 680 in an tions return by following the continen- hour—a promising start to the day. But, tal coastline back to India. This round as the morning progresses, the winds trip of more than eleven thousand miles strengthen, the sky becomes overcast, (nearly eighteen thousand kilometers) is and dragonfly activity ceases. almost twice the maximum distance of Unfortunately, this weather pattern the monarch’s migration. persisted for the remainder of the week After negotiating the steep climb and we didn’t see any further dragonfly to the hilltop banding station, we find migrations during our stay. This was

SPRING 2011 25 wandering glider; some engage in an- nual seasonal migrations and others are more sporadic. The best-known migrant dragonfly is the common green darner, which makes mass flights each fall in the thousands or millions, traveling from southern Canada and the north- ern United States down into the south- ern United States, northern Mexico, and parts of the West Indies. Midwesterners can follow clouds of migratory dragon- flies along the shores of the Great Lakes, while residents of western states may see thousands of variegated meadow- hawks (Sympetrum corruptum) sweeping south in the fall. Other North American dragonflies that are considered regular The band-winged dragonlet (Erythrodiplax umbrata) is one of eighteen dragonfly spe- migrants are the band-winged dragonlet cies in North America that regularly mi- (Erythrodiplax umbrata), the spot-winged grate. Photograph by Celeste Mazzacano. glider (Pantala hymenaea), and several species of saddlebags (Tramea). frustrating but these flights are known Confirming a species as a true mi- to be sporadic and discontinuous, with grant is complicated, as dragonflies are large numbers moving in mass flights for strong fliers and may disperse over long a few days followed by gaps in which few distances if the habitat in which adults to no migrants are observed, so even had emerged becomes unsuitable. Further- the weather been perfect we still might more, the magnitude of migration can have seen no dragonflies. Were the ones differ from year to year—and from day we counted that first day part of a true to day within a given year—making it migratory cohort or simply a handful of difficult to observe, and documenta- residents moving south along the coast tion of springtime’s smaller returning with the winds? This is a question we flights is sparse. Identifying the species were unable to answer, and one that will in a mass flight can also be challenging, require future study. as individuals may fly well overhead; a Dragonfly migration is not a newly glimpse from below of flashing wings recorded phenomenon; the first written and patterned abdomens may be all an reports of mass migration date back to observer has to go by. the mid-nineteenth century. Migrations Although dragonfly migration has occur on every continent but Antarcti- been documented for well over a centu- ca, and flights are often seen following ry, there is still much to be learned about such topographic edges as ridges, cliffs, this phenomenon. For example, we lack coastlines, and lake shores. North Amer- basic information, such as what environ- ica may have as many as eighteen migra- mental cues trigger migratory behavior tory dragonfly species, including the and where the dragonfly overwintering

26 WINGS grounds are. We don’t know details of the structure of the group and establish how the dragonflies migrate: Do indi- its working priorities. Scott Hoffman viduals that take wing in Canada alight Black, executive director of the Xerces in Mexico or do they routinely join and Society, was named chair of the new leave a migratory flight? How do they partnership, with John Abbott of the navigate along the flight path? Nor do University of Texas at Austin as vice- we know whether the individuals that chair. The author and her companions overwinter in the south fly north in the at Cansaburro, Doug Taron and Elisa spring, or whether migrants mate and Peresbarbosa Rojas, are members of the lay eggs at suitable habitats along their partnership, as are Jim Chu, Carol Lively, routes. In some respects we are in a posi- and Michael J. Rizo, U.S. Forest Service tion similar to that of biologists study- International Programs; Ralph Grun- ing monarch butterflies forty years ago. del, U.S. Geological Survey; Matthew Although we know there is a phenom- Jeffery, Audubon Society International enon, we know little about it. Alliances Program; Colin Jones, Ontario In an attempt to answer these and Ministry of Natural Resources, Canada; other questions, dragonfly experts, con- Peter Marra and Colin Studds, Smith- servationists, and federal agencies have sonian Conservation Biology Institute; spearheaded the formation of the Migra- John Matthews, World Wildlife Fund tory Dragonfly Partnership, a collabora- Freshwater Program; Mike May, Rutgers tion aimed at better understanding and University; and Dennis Paulson, Slater conservation of dragonflies and their Museum of Natural History, retired. migration. In December 2010 a meeting The goal of the Migratory Dragonfly was held in Austin, Texas, to determine Partnership is to combine research and

The variegated meadowhawk (Sympetrum corruptum) migrates along the ­Pacific coast in the fall. Photograph by Dennis Paulson.

SPRING 2011 27 citizen science with education and out- ment—traces of which remain locked reach to gain better understanding of into the wing tissue of the adult follow- North America’s migrating dragonflies ing emergence. By comparing the ratio and, in time, to promote conservation of hydrogen isotopes in its wings to that of the habitat on which they rely. The of the water body where the insect was partnership will begin by focusing on captured, researchers can estimate how two major initiatives. The first involves far a dragonfly has moved from its emer- building a network of citizen-scientist gence site, measured in degrees of lati- monitors across Canada, Mexico, and tude. Such isotopic data will increase our the United States to track the spring and understanding of the points of origin of fall movement of the four most com- dragonflies in a mass flight, better delin- mon migratory species in North Amer- eate southern and northern endpoints ica: the common green darner, varie- of migration, and help distinguish mi- gated meadowhawk, wandering glider, gratory individuals from residents. and black saddlebags. The partnership North America’s migrant dragonflies hopes to develop the tools and resources are not currently rare or endangered, needed to enable participants to moni- but, with the mystery surrounding mi- tor the timing, location, duration, and gratory cues, pathways, and overwin- direction of travel of migratory dragon- tering grounds, we could put dragonfly fly flights, and to identify the species migration at risk without detecting it involved. Regular monitoring and cen- until it was too late. Continuing threats tralized reporting via the Odonata Cen- to wetland habitats, coupled with the tral web site will facilitate identification effects of global climate change, could of changes in species’ ranges, increase alter environmental cues for migration, public awareness of the importance of affect the timing of larval development odonates (dragonflies and damselflies), and adult emergence, disrupt migratory and enable additional conservation at- corridors, or render overwintering habi- tention to be focused on vulnerable spe- tat unsuitable. In finding answers to the cies and habitats. many questions about dragonfly migra- The second major initiative involves tion, we will better understand the role using isotopic signatures (also called iso- of this behavior in the survival of migra- topic fingerprints) to determine how far tory species. This project will also help a migrating dragonfly has traveled from increase conservation of wetland habi- its point of origin, a technique that has tat for all odonates, ubiquitous or rare, been used in the study of migratory ensuring that dragonflies by the mil- birds. Isotopes are different forms of a lions remain on the wing across North chemical element, each with a slightly America for years to come. different atomic structure; these dif- ferences vary characteristically with latitude. For dragonflies, an isotopic Celeste Mazzacano is staf­f­ scientist and signature is the ratio between stable director of­ the Xerces Society’s Aquatic isotopes of hydrogen—a component of Program, f­or which her work addresses in­ the water in the wetlands and streams vertebrates in streams, wetlands, bogs, and in which the larvae live during develop- springs.

28 WINGS XERCES NEWS

Thomas Eisner It was with great sadness that we learned and a piano was a permanent fixture in of the recent death of Dr. Thomas Eisner. his Cornell University lab. Tom was president of the Xerces Society At Cornell, Tom’s research crossed for many years, but his contributions to boundaries between disciplines as he our knowledge of insects and their con- pioneered the field of chemical ecology. servation go far beyond that role. He explored the ways in which insects Many people know the work of Tom use chemicals to communicate, mate, Eisner without realizing it was his. His defend, and eat. When teaching, his photographs of a tethered bombardier lectures were standing-room only. beetle twisting its abdomen to squirt a Tom believed that scientists had an boiling-hot chemical directly at its at- ethical obligation to be conservation- tacker have been widely published and ists. As a tireless advocate for inverte- are instantly recognizable. They also brates he spoke out on issues ranging elegantly encapsulate his life: his acute from the protection of tropical forests to observations of natural history led to endangered species. He also was a gifted the innovative design of an experiment writer, with more than five hundred ar- to investigate the little-known subject ticles and books published. of the ways insects use chemicals, and it “Once you fall in love with them, was all captured with top-notch photog- you can’t fall out of love,” he said of in- raphy. The only thing that’s missing is sects in an interview on National Public music. Tom was a concert-grade pianist, radio. “There’s no end to the marvel.”

Xerces Moves to Protect Cold-Water-Dependent Insects Among the animals most threatened by ing for the most vulnerable cold-water climate change are those that depend invertebrates —the Arapahoe snowfly upon cold-water habitats. They require (Capnia arapahoe), the western glacier cool, clear rivers and streams fed by stonefly Zapada( glacier), the Gila may- glacial meltwater and snow melt, two fly (Lachlania dencyanna), the straight sources that are becoming less depend- snowfly Capnia( lineata), and the Idaho able in the face of a warming climate snowfly Capnia( zukeli). ESA protection and changing precipitation patterns. would mean that habitat of these insects It is vital that we ensure that the would be protected and restored. creeks these species live in are not fur- To date, the U. S. Fish and Wildlife ther degraded by water diversion, graz- Service has responded on just one of ing, extensive recreation, pollution, and these species, the Arapahoe snowfly, de- other activities. The Xerces Society has termining that protection may be war- asked for Endangered Species Act list- ranted and initiating a status review.

SPRING 2011 29 Xerces Ramps Up Efforts to Protect Bumble Bees Recent work by the Xerces Society and (Bombus f­ranklini) as endangered under leading bumble bee researchers has the Endangered Species Act. established that at least five species of In November 2010 a diverse group formerly common North American of researchers, conservation groups, bumble bees are declining and at least commercial producers, and agencies two species are now facing extinction. gathered at the St. Louis Zoo to develop The Society is leading efforts to protect a conservation strategy for North Amer- the most imperiled bumble bees and ican bumble bees. We worked with mul- educate people about how they can help tiple partners to convene this meeting, these animals. including the Conservation Breeding A petition was submitted to the U.S. Specialist Group of the International Department of Agriculture’s Animal Union for Conservation of Nature and Plant Health Inspection Service (IUCN), the St. Louis Zoo, the USDA’s in early 2010 to request regulation of Pollinating Insects Research Unit, and the interstate shipping of commercial the University of Illinois. The meeting bumble bees in order to protect wild enabled unprecedented cooperation, bees from diseases carried by these ship- which we hope will culminate in an ef- ments. This action was supported by fective conservation plan. many scientists, citizens, and farming The Society also helped launch and conservation groups. In addition, the IUCN Bumblebee Specialist Group, working with Dr. Robbin Thorp, we filed which will engage researchers to con- a petition to ask the U.S Fish and Wild- duct a global status assessment of the life Service to list Franklin’s bumble bee world’s approximately 250 species of

Rusty-patched bumble bee (Bombus affinis), photographed by citi- zen monitor Johanna James-Heinz in Peoria, Illinois.

30 WINGS bumble bees, in order to prioritize their has been highly successful at expanding conservation. The group is chaired by our knowledge of where rare and declin- Dr. Paul Williams of the Natural His- ing species still occur. For example, the tory Museum in London; Sarina Jepsen, highly imperiled rusty-patched bumble director of the Xerces Society’s Endan- bee (Bombus af­finis) is known only from gered Species Program, is deputy chair. a few locations in six U.S. states and one Over the past three years, Xerces Canadian province. Discoveries of this has engaged hundreds of citizens to species in Massachusetts, Minnesota, search for bumble bees and submit their and Pennsylvania were made by Xerces photographs to the Society. This project Society citizen monitors.

Advocacy Pushes County to Protect Rare Fender’s Blue Butterfly Fender’s blue (Icaricia icarioides f­enderi) Recently, working with a coalition of is an endangered butterfly living in Ore­ local citizens and conservation groups, gon’s Willamette Valley. The butterfly’s the Xerces Society sent the County a host plant is Kincaid’s lupine (Lupinus notice of intent to sue. As a direct result sulphureus ssp. kincaidii), which itself of this action, Yamhill County is devel- is threatened. Since 2001 the U.S. Fish oping a Habitat Conservation Plan to and Wildlife Service has documented guide its road-maintenance efforts to incidences in which Yamhill County’s avoid further harming the Fender’s blue. roadside-maintenance activities have Where disturbance cannot be avoided, harmed the lupine in violation of the the plan will specify ways in which the Endangered Species Act. These activities County can mitigate for the harm it has impact the butterfly as well. caused.

WINGS, Spring 2011 Volume 34, Number 1 Wings is published twice a year by the Xerces Society, an international, non- profit ro ganization dedicated to protecting the diversity of life through the ­conservation of invertebrates and their habitat. A Xerces Society membership costs $30 per year (tax-deductible) and includes a subscription to Wings. Copyright © 2011 by the Xerces Society. All rights reserved. Xerces Society Executive Director: Scott Hoffman Black; Editors: Scott Hoffman Black, John Laursen, and Matthew Shepherd; Design and Production: John Laursen. Printed on recycled paper. For information about membership and our conservation programs for native pollinators, endangered species, and aquatic invertebrates, contact us: THE XERCES SOCIETY FOR INVERTEBRATE CONSERVATION 4828 Southeast Hawthorne Boulevard, Portland, OR 97215 telephone 503-232-6639 fax 503-233-6794 [email protected] www.xerces.org

SPRING 2011 31 Residents of temperate areas may think of crabs as marine creatures, something to look for on beach trips, but, in warmer regions, some crabs —including this Potamonautes sp.—have adapted to life on land. Photographed in South Africa by Piotr Naskrecki.

THE XERCES SOCIETY FOR INVERTEBRATE CONSERVATION 4828 Southeast Hawthorne Boulevard, Portland, OR 97215

Board of Directors Counselors Dennis Paulson May R. Berenbaum Paul R. Ehrlich Robert Michael Pyle President Boris Kondratieff Michael Samways Linda Craig Claire Kremen Cheryl Schultz Treasurer John Losey Robbin Thorpe Sacha Spector Thomas Lovejoy Scientific Advisor Secretary Jerrold Meinwald E. O. Wilson David Johnson Michael G. Morris Scott E. Miller Piotr Naskrecki Marla Spivak Paul A. Opler

A $30 per year Xerces Society membership includes a subscription to Wings.

Our cover photograph is of a woollypod milkweed plant (Asclepias eriocarpa). With more than a hundred species in North America, milkweeds support a highly diverse ­community of insects. Photograph by Aaron Schusteff.