Drain Fly Psychoda alternata, Telmatoscopus albipunctatus, or similar species

cottonmanifesto found this creature in our bathroom sink. At first it was a paradox: It seemed to have two wings, like a fly, but it had long antennae and looked fuzzy, like a moth. It was a quick job to narrow the field down to "moth flies" (family Psychodidae), a group of very small flies that breed in wet, decaying organic matter.

Drain flies specifically breed in the kind of very wet, bacteria rich organic matter that accumulates in clogged gutters, rain soaked trash cans, and old household plumbing. They do not bite (though close relatives called sand flies are blood suckers), or infest food, though one imagines that they could spread disease-causing bacteria from one place to another. In at least one case in South Africa, drain flies were found to cause health problems for sewer workers, who were inhaling large quantities of them. Controls for this animal, when deemed a pest, include cleaning and unclogging drains--and at least one product is specifically designed to help cope with them. It consists of a cocktail of competing bacteria that are supposed to eat the drain fly maggots' nursery out from under them.

Moth flies are weak fliers, but are small enough to pass through window screens. Once outside they become a component of aerial plankton, adrift beyond their control, hoping to land sometime in their 2 week adult life span near another fount of bacterial slime in which to lay their eggs. I did not find it in my research, but I propose that sometimes when one finds a house centipede stranded in a sink or bathtub, that they are hunting drain flies.

Plains lubber grasshoppper Brachystola magna

This large western grasshopper eats a wide variety of plants and is considered a pest of sunflower and cotton, but it also likes the taste of ragweed and dandelion. It lives in the grasslands of the American west, thriving in disturbed landscapes and occasionally increasing in numbers to plague proportions. Unlike many other grasshoppers its wings are reduced and it cannot fly.

This individual is in the invertebrate zoo in "A Bird's World" exhibit.

On this day in 365 urban species: Another day off, as my Dad and I made a stop in Forks, Washington.

Photo by urbpan. Location: Forest Park, Springfield, Mass.

Urban species #348: Hemlock Woolly Adelgid Adelges tsugae

This insect spends most of its life hidden in a fluffy white shelter. It sucks the fluid from the needles of hemlock trees, and it is believed that as it feeds it introduces a toxic substance into the tree. Every plant has sap-sucking pests that feed on them, and most are not seriously damaging. An infestation of these hemlock woolly adelgid can cut the lifespan of an eastern hemlock down from hundreds of years to less than ten. The Asian hemlocks that the insect feeds on in its native range developed resistances that allow the trees and adelgids to coexist.

Adelgids are close relatives of aphids. Like some aphids, hemlock woolly adelgids are all female, and several generations are born in a single year. In the short time that the insects are mobile, they are carried from tree to tree by animals or by the wind. Adelgids have fully infested the hemlocks in all counties of southern New England, as well as the areas around New York CIty, Philadelphia, Washington D.C. and New Jersey. It's possible that the adelgid affects urban trees more severely because they are already weakened by pollution and other stresses. Methods to control the infestation include saturation of individual trees with pesticide, and the introduction of predatory beetles.

Mating swarms of non-biting midges drift in the mid-day air on an unusually warm December day in Hartford. River birches frame the photo. Photo by urbpan. Location: The Riverwalk, Hartford, Connecticut.

Urban species #347: Non-biting midge Family: Chironimidae

A column of insects gathers in the air, slowly drifting, sometimes toward a light source, sometimes toward an object such as a passing human. The column may be a small vertical puff of a few feet, or a towering nimbus hovering from face level up to thirty feet tall. If you are like me, you swish your hat through the cloud to catch one or two of these tiny flyers, to see what they are. You may be alarmed to see what looks like a mosquito! But if they were all mosquitoes you would be covered with bites by now. Midges can be told from mosquitoes by the lack of scales on their wings, different mouthparts, and by the fact that their front pair of legs is their longest. The cloud moves on, perhaps leaving one or two tiny flies in your hair or, if you were riding through on your bike, your eye.

The insects are midges, specifically "non-biting" or "chironomid" midges. (They are called non-biting midges to distinguish them from small biting flies such as no-see-ums, which are sometimes called midges.) The columns are mating swarms, and the vast majority of the midges in the swarms are the males. Male midges (and males of mosquitoes and moths) can be recognized by their plumose, or featherlike antennae. These are surface-area maximizing structures which catch scent molecules and draw the males to their purpose.

Midges are almost always found near fresh water, where they live as larvae. Midge larvae are among the most abundant and important aquatic invertebrates. They are food for other insects, as well as young fish and amphibians. Astute ecologists can determine a great deal about a body of water by the midges that live in it. Each species can tolerate different levels of different pollutants, as well as different pH levels, temperatures, levels of oxygenation and so on.

Adult midges, though tiny, can be important food for birds and bats. Swallows and swifts are drawn to bodies of water to catch the adults as soon as they emerge from their aquatic pupae. One imagines that this swarm of midges photographed at the bank of the Connecticut River in December has an adaptive advantage: by engaging in the mating swarm in winter, they have thwarted their bird, bat, and dragonfly predators, who have migrated or are hibernating.


A male midge swept out of its swarm with my hat.

Thanks for identification help from rockbalancer!
also nutmeg and phlogiston_5

Photos by urbpan. A fastidious little animal cleans up, after being manhandled in a plastic bag to be photographed.

Urban species #238: Housefly Musca domestica

Like other animals with the common name "house-" or the scientific name "domestica," the housefly is found almost exclusively in and around buildings. Where the housefly lived before there were houses (or more importantly, stables) is lost in prehistory; houseflies have lived alongside humans since before we kept track of such things. It was known to live among us when it was first given a scientific name by Linnaeus in 1758. They may originally be from Africa, but in any case seem to be tropical animals; As with some other tropical animals, like American cockroaches, they survive in the artificial tropics that we provide in our heated buildings. Houseflies are omnivorous scavengers, feeding on anything moist and organic. Their mouthparts are not built for chewing, but rather for mopping up. Most food is not moppable, so they vomit their digestive juices onto what they want to eat, transferring bacteria from the last thing they ate. In some places, such as poultry houses and crowded tropics, they are serious disease vectors. Their eggs are laid in food sources, which in rare cases includes open wounds. More often their young are found having hatched in particularly ripe garbage. Baby flies are an indication that the trash needs to be taken out more often.

Photo by cottonmanifesto. Location: Olmsted Park.

Urban species #323: Devil's coach horse Staphylinus olens

First, I must confess to another tentative and perhaps dubious identification. In my defense, there are more named species of insects than any other life form, more species of beetles than any other insect, and in North America, more species of rove beetles than any other beetle family. That being said, this creature looks very much to me like a devil's coach horse, a European rove beetle widely introduced to gardens and yards around the world.

You might think that underneath a log is nice safe place for detritus-feeding animals, peacefully grazing on rot-softened organic matter. But the maggots, earthworms, and woodlice are preyed upon by the devil's coach horse. With powerful mandibles that can deliver a painful bite to a human finger, they chop up their invertebrate prey into chunks. The devil's coach horse is among the largest of the rove beetles, and even feed on other predatory animals, such as the woodlouse spider.

Rove beetles are distinguished by their very short wings, which make them look rather un-beetlelike. Rove beetles' incomplete wing covers (called "elytra") don't cover their abdomens, causing them to be sometimes confused with earwigs. Devil's coach horse beetles bend their abdomens when disturbed, much as earwigs do, but they also emit a foul-smelling fluid. This behavior has earned them the alternate common name "cocktail." I think "devil's coach horse" sounds cooler.

Photos by urbpan. Location: common milkweed plant on the shore of Leverett Pond, Boston.

Urban species #310: Oleander aphid Aphis nerii

There are a few species of aphids which are generalists, feeding on a range of different plants. Most, however, drink the juices of a small subset of similar plants, such as the lettuce aphid (which feeds primarily on lettuce, but may also feed on artichoke and petunias) and the oleander aphid. The oleander aphid is thought to have originated in the Mediterranean, but has now spread worldwide, having been exported along with its host plant. Of course, oleander is a subtropical plant, so in order for the oleander aphid to spread to northern regions, it needed to find an alternate host. It has found that milkweed plants serve quite nicely. In places where oldeander will not grow, this insect may be called "milkweed aphid."

One thing that oleander and milkweeds have in common is that they are both quite toxic, bearing chemicals called cardenolides. Oleander aphids are able to take this poison from their host plant and store it. When a predator attacks, cardenolides are emitted from "cornicles," which are appendages on the top of the insect's abdomen. Usually this repels the predator, but if not, the poison does its dirty work. In an aphid predator such as a lacewing or ladybug, the poison can render the insect sterile, or interfere with wing development. The aphid presents a fair warning in its coloration: bright yellow-orange with contrasting black appendages. This caution sign combination works for all kinds of bees as well as the monarch butterfly (another milkweed feeder that uses cadenolides in defense).

Oleander aphids are thought to be all female, reproducing through parthenogenesis. Generation of wingless daughters and granddaughters are born and spread until they reach a point when the plant can support no more of them. Then a generation of winged aphids is born and they fly to new host plants. Like many other aphids, oleander aphids produce honeydew as excrement, but their honeydew contains the same poison they use to protect themselves. Some species of aphid are protected ("tended") by ants, who consume the honeydew. The giant milkweed we examined in Antigua had both aphids and ants; are there certain ants that can cope with the poison? Or since worker ants are both wingless and sterile, is the poison's effect moot? I hope this question is explored in the entomological literature, but I could not find it. It does seem that while the aphid causes little harm to the host plant, the uneaten honeydew accumulates and grows a fungus called "sooty mold," which is considered unsightly.

Oleander is a widely planted ornamental in cities throughout the tropical and subtropical world. Milkweeds such as butterflyweed are likewise planted, in temperate cities and suburbs. And common milkweed and giant milkweed survive in roadsides, parks, and vacant lots everywhere. Wherever these plants are, they are accompanied by their aphids.

( context and close-up )

Photos by urbpan. Location: Olmsted Park, Boston.

Urban species #290: Wooly bear

Along with ladybugs, wooly bear caterpillars are among the most adored of the insects. This is not due to any function or service that they perform, simply their attractive, panda-like appearance, and the lack (or concealment) of such objectionable insect features as creepy abdominal segments, horrible mandibles, ugly appendages, and alarming pinchers. As far as most people are concerned, wooly bears are simply tiny cylindrical mammals. While it's nice to see at least one insect admired, it's baffling that very similar animals that have patchy "fur," or none at all, are reviled. Caterpillar hair is a defensive structure which helps prevent birds and other predators from eating the butterfly or moth larvae. Some caterpillar bristles contain venom and are dangerous to touch, but wooly bears can be handled safely.

Wooly bears are common throughout North America. Unlike picky specialists like the monarch, these caterpillars will eat nearly anything, from the dandelions to maples and many other plants in between. Introduced plants such as plantains may help increase the numbers of wooly bears in cities--these plants persist late into the fall and even winter, allowing the caterpillars a longer feeding season. Wooly bears are conspicuously active in fall, seen crossing sidewalks in search of a place to hide and sleep through the winter. In spring the caterpillars wake up and pupate, transforming into Isabella tiger moths, rather nondescript yellowish brown creatures.

( Read more... )

Photo by urbpan. I found this camel cricket (and many others) under a makeshift bed, used by homeless people in a wooded section of Olmsted Park, in Boston.

Urban species #282: Camel cricket Ceuthophilus spp.

Camel crickets are also sometimes called "cave crickets," and while there are some specialized species that inhabit only caves, most of these insects have more general habits. They are nocturnal and are found gathering in cool dark places, sometimes in surprising numbers. Apparently they are occasionally mistaken for spiders, with their long slender appendages and lack of wings. Their shiny, humped bodies and long antennae should put that misidentification to rest, if you haven't already flattened them. Like many other insects called crickets (though, evolutionarily they are more closely related to katydids) camel crickets are omnivorous, feeding on the carcasses of other insects and decaying plant matter. They are sometimes considered pests, mainly because they will enter homes and basements for shelter, but they are not destructive animals. They are not especially well-studied creatures, and identification to species is difficult and rare, with most authorities either leaving the designation blank, or arbitrarily settling on C. maculatus (an apparently common and cosmopolitan species.)


Long hind legs can be a liability, but camel crickets can make do with just one, if a predator takes the other.

Urban species #275: Silverfish Lepisma saccharina

Forgive me please, and my blurry photographs. These things are so damn fast! I discovered this individual quite by accident. I was walking through the concourse between the Washington Street stop and the Park Street stop in the subway, when I happened to see two large American cockroaches. While I was taking pictures of them, a whitish blur zipped by. I couldn't believe my luck: I stopped for one urban species and found another. Too bad I didn't get better photographs.

This rapid-moving subway dwelling insect is a silverfish. It's belongs to an ancient group of animals; silverfish evolved before Nature thought to provide insects with wings. When humans came along hundreds of millions of years later, silverfish took advantage of our warm buildings full of starchy, plant-based objects. They come into homes, lurking in crevices and moving at night, and feeding on textiles, glues, paper, and other substances. They cause no bodily harm or disease to their primate landlords, though many people are alarmed by their appearance. Their bodies are covered with tiny scales that give them a silvery look and a slippery texture. Their rapid scuttling, like that of cockroaches and house centipedes, can be an unsettling surprise in the night.
( Read more... )

Urban species #261: Oak apple gall wasp Amphibolips confluenta

Acorns aren't the only round objects falling from oak trees this time of year. Spheres, about the size of golf balls or slightly smaller, green and mottled with red, mysteriously appear on the sidewalk. Later, many more will be found--larger, light brown like dead leaves, sometimes entire, more often with a single hole in the thin crust. These mysterious objects are not pods from outer space, or oak tumors; they are galls: the protective nurseries for young insects, usually given the quaint name "oak apples." The mother insect enlists the help of oak trees, symbolic of strength and live itself, to shelter her growing offspring. Known, somewhat anticlimactically, as the oak gall wasp, the tiny non-stinging insect deposits her egg in the flesh of an oak leaf. Along with the egg is a hormone that induces the oak tree to form a gall around the wasp egg. The larva develops within a shield of plant material, a capsule suspended in the center of the orb.

At least 200 species of organisms use oak trees to form galls of one kind or another. Other plants that often play host to gall wasps and gall mites and other creatures include goldenrods, maples, and roses. Galls cause very little damage to the host plant, and gall wasps are not considered to be serious pests.

The gall is not an impregnable fortress, and many predators recognize wasp galls as sources of food. Birds, notably woodpeckers and chickadees, poke holes in galls when they encounter them aloft. Fallen galls are fair game for squirrels and other mammals, and enterprising predatory wasps may gnaw their way into galls in trees and on the ground. If the gall wasp larva escapes all these predators and survives to adulthood, it chews its way out, leaving a small neat hole in the papery gall, which falls with the leaves of autumn.


Sliced open to see the larva inside.

( see the larva close up )

Photo by cottonmanifesto. Location: Olmsted Park, Boston.
Urban species #258: Bumblebee Bombus pennsylvanicus

Until this year, I assumed I was seeing bumblebees almost every warm day of every year, and then I discovered I was actually seeing carpenter bees. One easy way to tell the difference is that the bumblebees have furry abdomens while carpenter bees have shiny black hairless abdomen. Bumblebees are familiar, almost friendly-seeming, with their thick fur and clumsy way about them. Their yellow and black markings, like those of many other stinging insects, are meant to warn predators. Stinging hymenopterans (that is, members of the order of insects that includes bees, wasps, ants, and others) are armed with venom-injecting weapon derived from their ovipositor. This means that only females can sting. Bumblebees are considered unaggressive and unlikely to sting. Like their close relatives, the honeybees, bumblebees are social, a hive of up to 300 individuals and their mother, the queen, working cooperatively to raise the next generation. Unlike honeybees, bumblebee colonies do not overwinter; only the queen (or her successor) survives. Bumblebees are highly valued as pollinators, with some plant nurseries and farms purchasing hives for this purpose; their small untidy combs not producing enough honey to make collecting it very rewarding.


Photo by cottonmanifesto. Location: our front step.

Urban species #259: White-faced hornet Dolichovespula maculata

Even this entomophile shudders a little bit at the sight of a swarm of white-faced hornets (also called "bald-faced hornets"). These wasps are very aggressive, and deliver a painful sting. Their large gray paper nests are often attached to buildings, although they also can be found in trees. Each nest, which can be a foot in diameter or more, is made of several layers of chewed wood, and contains between dozens and hundreds of individuals. The larva are fed flower nectar, and the bodies of other insects that the adults have killed and chewed into bits. White-faced hornets are ambitious predators, even attacking large and dangerous prey like their close relatives, the yellowjackets. Despite the danger of their sting, these insects are beneficial, preying on pests, and acting as pollinators. White-faced hornets are found across North America, except for the dry interior plains, and are common in urban parks and suburban neighborhoods.

Photos by cottonmanifesto. Location Brookline Ave and Francis Street, Boston.

Urban species #256: Greater angle-winged katydid Microcentrum rhombifolium

Tick tick tick tick tick tick ticktickticktickticktick!

This is the sound of an insect that was mysterious to me for a long time. It ticked away, slowly first, then faster and urgently, like a timer on an explosive. It was hidden in high vegetation, way up in trees and in the ivy up by our second-floor windows. I assumed it was a beetle, perhaps a death watch beetle, whatever that is, ticking away, reminding us of our limited time left on earth. As it turns out, a friend of mine in Somerville (the most densely populated city in the U.S., a little city across the river from Boston) managed to follow the sound to its source, and found something much more benign. The greater angle-winged katydid makes his ticking call, like all noisy male animals, to announce his presence to potential mates. The loud song is important, because these insects are incredibly well-camouflaged: flattened like a leaf, and including details like wing veins that look like leaf veins. I still wonder how it is that the great golden digger wasp is able to locate katydids to provision her nest, since the wasp is active during the day, and the katydids sing at night. There are six species of angle-winged katydids, and the best authority I could find on the subject omitted New England from their range maps. It is possible that they have newly spread to eastern urban areas in ornamental plantings from further west. "True" katydids, the ones that sing their names, make up a small subfamily of the family Tettigoniidae ("long horned" grasshoppers: those grasshoppers that have antennae as long as their bodies). The greater angle-winged katydid is the only long-horned grasshopper that I have encountered in the city so far.


Location: Puddingstone Park, Mission Hill, Boston.

Urban species #257: Red-legged grasshopper Melanoplus femur-rubrum

If you walk through a grassy field, or a vacant lot choked with weeds, chances are you will stir up grasshoppers. Chances are very good that one of the species you stir up will be the red-legged grasshopper. This "short-horned" grasshopper (it's antennae are considerably shorter than the length of its body) is one of the most widely distributed grasshoppers in North America. It is found nearly everywhere in Canada and the United States and in the northern half of Mexico. It feeds on a variety of different plants, including common urban species such as Russian thistle (tumbleweed), fleabane, vetch, ragweed, and many different grasses. All of these plants are prevalent in areas that are infrequently but regularly mowed, like roadsides. Grasshoppers are important prey for many different animals, especially birds, including large species such as turkeys, herons, and birds of prey (even large hawks such as the red-tailed hawk.

( Read more... )

I found this roach upside-down in a business in Austin. I picked it up (to photograph it in a more discrete location) when it squirmed and wriggled--crippled by poison but still alive. Regaining my composure, I brought it out into the harsh Texas sun and took this picture.

Urban species #255: American cockroach Periplaneta americana

The cockroach is evolution's way of saying "if it ain't broke, don't fix it." Little changed in 300 million years, this insect has watched the continents drift apart, the dinosaurs come and go, and, many people suspect, will watch indifferently as humans disappear. They are successful in pristine tropical rainforests as well as in the densest and most polluted cities on earth. Despised by most people, killed on sight, and dwelling in buildings that are repeatedly bombed with insecticide, they continue to thrive. There are non-urban roaches, by the way, and they make up the vast majority: of more than 3000 species of roaches, only a handful (about 1-2% of total species) inhabit the worlds' cities.

The so-called American cockroach, like most other urban cockroaches, is thought to have originally come from Africa. When trade between that continent and North America was at its most notorious--when humans were a product to buy and sell--cockroaches stowed away in ships. These insects feed on nearly any organic matter, but can even survive without any food whatsoever for over a month. They can survive in tight gaps, in fact they actively seek them out, finding comfort in pressure above and below their bodies, packing together in great numbers. They hide from light, an attribute memorable to anyone who has flipped on the switch in a roach-infested kitchen. In their native environment of the moist forest, cockroaches are valuable detritivores, feeding on decaying vegetation and helping turn waste into fertilizer. They have no qualms about eating animal based food either, eating the shed skins (exuviae) and carcasses of insects. In a home or business they are less valuable, known to track filth into food, and leaving a disagreeable odor where they congregate. They are well-known symbols of filthiness--living emblems of the worst aspects of urban living. They have even been implicated in a rise in the rate of asthma in inner city children, who may be affected by allergies to roaches or their droppings.

At up to two inches long or more, American cockroaches are the largest of the roaches commonly found in North America. Landlords euphemistically refer to them as "water bugs" due to their attraction to the heat and moisture of plumbing, or as "palmetto bugs" (presumably because in southern states they are associated with palmetto plants). In northern states they are confined to the warmest and most humid parts of buildings--Boston's sewers, subways and extensive connected basements host untold millions of American cockroaches. In the south they are more free animals, coming in to homes and businesses to feed, but also roaming the outdoors. In the north, cockroaches are swift runners, and that is all, but in the south the heat grants them the power of flight. I finally witnessed this firsthand this past week in Austin, when one flew into the open patio of a bar at night, and landed on the bare shoulder of a patron. She squealed and flailed, and the insect flew one circle around a light before it landed on a wall, scuttling up and disappearing in a fraction of a second. It was only then that I realized what it was. Another new urban nature experience to enrich my life!


This American cockroach was running down an alley behind a 6th street bar in Austin. Unfortunately my photography when on long-distance field assignments (some call them vacations) is in need of improvement. Readers are encouraged to submit their own cockroach pictures in the comments section.

( Just added: Boston cockroaches! )

Any entomologists interested in helping me on this one? I'm pretty sure it's either Chlorion aerarium or Chalybion californicum. If only I'd watched it long enough to see it grab a spider or a field cricket.



( two pictures by cottonmanifesto )

Photos by urbpan. Location: Drumlin Farm.

Urban species #243: Pavement ant Tetramorium caespitum

Little piles of dirt form on sidewalk cracks, busy with tiny goings-on. Only an eighth of an inch long (3mm), each pavement ant is a member of a colony of perhaps three of four thousand individuals. There are several queens in each colony, a fact that probably contributes to the great success and wide distribution of this species. This ant is native to Europe, but like many other European invertebrates (including, but not limited to the nightcrawler, woodlouse, woodlouse spider, pill bug, and ground beetle) was introduced elsewhere in the soil ballast of ships. The cities on eastern half of North America can claim this ant as one of their most familiar creatures, and it is found in some Pacific coast places as well. Pavement ants collect carrion and insect carcasses, and will feed on a variety of different trash items also.


The winged, reproductive form of the pavement ant.

Photo by cottonmanifesto. Location: Olmsted Park, Boston.

Urban species #241: Great golden digger wasp Sphex ichneumoneus


Though its appearance may be fearsome to some people, the great golden digger wasp is not aggressive, and in fact, feeds only on flower nectar. Their young, however, deep in a vertical burrow in the soil, eat the paralyzed but still-living bodies of the animals provided by their otherwise peaceful herbivorous mother. This wasp is very particular about what food to provide for its larvae: it only chooses long-horned grasshoppers (Family tettigoniidae, which includes katydids). It seems hard to believe that there are enough katydids and their relatives to support this common and widespread wasp, but this group of grasshoppers is characterized by being extremely well-camouflaged. The adults feed on a variety of different flowers, though we always seem to find them on the blossoms of sweet pepperbush (Clethra alnifolia), a native shrub used in many city park plantings. Great golden digger wasps are found in most places in North America and in much of South America as well. As long as a given city has soil to dig in, flowers to feed on, and long-horned grasshoppers to provide for its larvae, it is likely also to have this species.

Many thanks to phlogiston for identifying this species. (If you would like to post your picture in the comments, that would be great!)

Photos by urbpan. I found this male stag beetle walking along the path in the Riverway, and transported him to the nearby Longwood trolley stop, where I could photograph him while I waited for my train.

Urban species #235: Stag beetle Lucanus capreolus

When different organisms evolve similar adaptations, we call it convergent evolution. The incredibly long list of examples includes complex eyes evolving in cephalopods and vertebrates, flight evolving in birds and bats, and even armored anteaters independently in the armadillo and pangolin lineages. In the same way, two very different groups of herbivorous animals have evolved ritualized combat behavior among males. This is why the stag beetle has come to have such fearsomely oversized mandibles, which are useless for eating, which is what nearly all other insects do with their mouthparts.

The species pictured here, Lucanus capreolus the reddish-brown stag beetle, or more evocatively, the pinching bug, is one of many. Its scientific name refers to the two-point mandibles of the male, compared in Latin to the horns of a goat. The larva of this species is a huge white grub that lives in rotten wood, enjoying the products of decomposition (especially our friends the wood-decay fungi) for two years. A plump stag beetle grub would be a delicious, energy-packed prize to any woodpecker or other predator who extracted it from its stump or log. Adult stag beetles lap up the juices and saps of trees and other plants. This observer has watched various birds, such as catbirds and grackles trying to worry the edible meat out of the formidably armored adult beetles.

Large beetles aren't usually thought of as urban species, at least not in colder temperate cities. But this beetle is a native of the great eastern forests of North America. Even though the this is now the most densely settled part of the continent, the return of farmland to forest means that stag beetle habitat actually increased during the twentieth century. Forested city parks provide urban refuge for this and many other woodland species.

( Put that beetle down! )

Photos by cottonmanifesto. Location: Spectacle Island, Boston.

Urban species #212: Japanese beetle Popillia japonica

I n 1916, America's most densely populated state (New Jersey) became the first place in North America where a certain exotic Asian scarab beetle was found. This beautiful but destructive animal is now well-known to gardeners in the eastern states, and is becoming familiar in more places every year. Increasing amounts of regulation and use of biological controls (a bacterium and parasitic wasps) are the official weapons in use against the Japanese beetle. Others may use a more hands-on approach, as my parents did in years past, hand-picking beetles by the hundreds, off of the raspberry and rose bushes, and dropping them into jugs of soapy water. Still they seem to have a robust population in areas where they occur, including urban centers that have the plants the adults feed on (over 400 species documented) and grassy soil for their grubs to overwinter in. And they continue to spread, being found in San Diego for the first time in 2000, and at an airport in Montana in 2002.

Japanese beetles are often encountered in what appears to be mating groups. Females produce sex pheromones that attract many males, who compete for the opportunity to mate in large clusters. According to one researcher, relatively little mating actually occurs in these groups. Males will guard their chosen female from other males until she is ready to lay her eggs. At least while clustered, they can be easily picked off of plants.

Skunks are known to make holes in lawns digging for Japanese beetle larvae, and moles and raccoons may eat some grubs as well. Other known predators of Japanese beetle larvae include ants and ground beetles. Few creatures seem to prey on the adults, though this observer has noticed at least one turkey seems to have a taste for them.

Photo by cottonmanifesto Location: Muddy River, near Longwood Station.

Urban species # 204: Blue dasher Pachydiplax longipennis

Dragonflies exist with a very curious mixed public image. Happily, the great majority of enlightened people recognize them as important predators, waging an aerial assault on the mosquito hordes that plague us. A significant minority of people are still alarmed by their appearance, mistaking them for stinging wasps or worse. Dragonflies are unable, as well as disinclined, to attack humans. They do not suck blood but instead catch whole prey in midair. Their young are even more misunderstood. Covered with muck, wingless and drab, a dragonfly nymph is a frightening ogre. Yet in its element, it's as important as its adult form, if not more so. Dragonfly larvae are the prey of sunfish, frogs, turtles. and herons. In this way they form an important link between the smallest and largest animals in an urban pond environment.


The blue dasher is a common, medium-sized dragonfly, found throughout most of populated North America. Any still water, from a canal, to a pond, to any number of industrial sites, can harbor enough prey to sustain some amount of dragonflies. Their pale blue body color and huge, shining green eyes make the blue dashers an exciting species to encounter. Hobbyists, similar to (and often drawn from the ranks of) birders, perch on the banks of marsh water, binoculars in hand, watching the territorial behaviors of these attractive insects. Conservation organizations have begun including "odonates" (dragonflies and damselflies) as a top taxonomic group in their biodiversity surveys.