Amazing Arachnids: Tarantulas

Adapted from pages 165-172 of Amazing Arachnids:

Tarantulas range in size from the largest spider in the world, Theraphosa blondi of South America, with a leg span of up to about 10 inches (25 cm), to Aphonopelma paloma, with a leg span of only 0.75 inches (2 cm).

Tarantulas also have a variety of lifestyles and behaviors, from the stereotypically solitary burrow dweller to the subsocial behavior of some communal species, such as the dwarf tarantula species Holothele (from South America) and Heterothele (from Africa). These communal spiders may cooperatively kill prey and young spiders share the kill. Circumstantial evidence suggests that even some species that live in underground burrows may have extended maternal care of young. In a number of instances, young tarantulas well beyond the third instar have been found  sharing an adult female’s burrow, leading to speculation regarding whether the mother shares food with her offspring.

Tarantula

Aphonopelma chalcodes adult male. These large males have a leg span of about 4 inches (10 cm) and are a common sight as they wander during the summer monsoon season (July and August) in southern Arizona.

The tarantulas of the southwestern United States belong to the genus Aphonopelma. These range in size from fairly large species such as Aphonopelma chalcodes, with a leg span of about 4 to 5 inches (10– 12.7 cm), to the tiny Aphonopelma paloma. A number of Aphonopelma are intermediate in size and are restricted to the mountains of southern Arizona. These tarantulas have a leg span of only about 2 inches (5 cm). The males mature in late fall or winter and may be seen as they wander in search of females even when there is snow on the ground. Because these mountain ranges are separated by barriers of low desert, many of the “sky island” populations have been geographically separated long enough that they are separate species.

One of the most common and conspicuous species is Aphonopelma chalcodes, also known as the desert blond tarantula. This handsome spider lives in an underground burrow in the low-elevation deserts of Arizona and may take about 10 years to reach maturity. The male looks markedly thinner and leggier than the female and, in addition, acquires a tibial spur on his front legs with his final molt. The males leave their burrows upon reaching maturity and go wandering in search of females. They are a familiar sight in the southern Arizona desert during the summer monsoon season, cruising at night or during the late afternoon, especially after a summer rain storm.

Hollywood has effectively exploited these fears, conjuring up giant tarantulas, deadly venomous tarantulas, and tarantulas that wipe out entire towns. But these animals have so much more to offer than cheap thrills. Their beauty and their diversity in both appearance and lifestyle defy the imagination and far surpass Hollywood’s wildest dreams. Certainly, they compel our respect, as does any predator capable of self-defense, but they also deserve our appreciation and protection.

We included a photo of one of the largest tarantulas – but what about the smallest? Head to our Instagram to see how tiny tarantulas can be. 

Amazing Arachnids coverAmazing Arachnids
By Jillian Cowles

The American Southwest is home to an extraordinary diversity of arachnids, from spitting spiders that squirt silk over their prey to scorpions that court one another with kissing and dancing. Amazing Arachnids presents these enigmatic creatures as you have never seen them before. Featuring a wealth of color photos of more than 300 different kinds of arachnids from eleven taxonomic orders–both rare and common species—this stunningly illustrated book reveals the secret lives of arachnids in breathtaking detail, including never-before-seen images of their underground behavior.

Amazing Arachnids covers all aspects of arachnid biology, such as anatomy, sociality, mimicry, camouflage, and venoms. You will meet bolas spiders that lure their victims with fake moth pheromones, fishing spiders that woo their mates with silk-wrapped gifts, chivalrous cellar spiders, tiny mites, and massive tarantulas, as well as many others. Along the way, you will learn why arachnids are living fossils in some respects and nimble opportunists in others, and how natural selection has perfected their sensory structures, defense mechanisms, reproductive strategies, and hunting methods.

  • Covers more than 300 different kinds of arachnids, including ones new to science
  • Features more than 750 stunning color photos
  • Describes every aspect of arachnid biology, from physiology to biogeography
  • Illustrates courtship and mating, birth, maternal care, hunting, and defense
  • Includes first-ever photos of the underground lives of schizomids and vinegaroons
  • Provides the first organized guide to macroscopic mites, including photos of living mites for easy reference

Amazing Arachnids: Orb Weavers

Adapted from pages 184-186 of Amazing Arachnids:

A delight to the eye and an engineering marvel, the orb web epitomizes the stereotypical spider web. It is built in a vertical plane, with strong, nonsticky silk radiating out from a central hub like the spokes of a wheel, supporting a spiral of evenly spaced sticky silk threads. A gap in the sticky silk near the hub allows the orb weaver to rapidly climb from one side of the web to the other, depending on which side of the web a flying insect has blundered into. Some orb weavers wait in the center of the web, legs stretched out in contact with the radiating silk lines that convey the vibrations of a struggling insect. Others build a little retreat at one side of the web, maintaining contact with the radiating lines via a signal thread leading to the hub. Lying in wait in the retreat, the spider rests with one leg touching the signal line. At the first indication that an insect has been caught, the spider moves into the web and tugs at the radial lines, testing to see the general location of the prey. It then uses the nonsticky radial lines as a quick pathway leading to the insect. Once the prey is reached, the spider uses large amounts of silk to wrap and immobilize it prior to settling in for the meal.

Many orb weavers build a fresh web every night and eat the silk by the next morning. Experiments with radioactive labeling have shown that spiders are the ultimate recyclers; up to 90 percent of the old silk is recycled into the new web, and such ingestion and reuse of the silk protein can occur in as little as 30 minutes. The spiral silk of the orb weavers owes its stickiness to the addition of little beads of viscous glue along its length, like the beads of a necklace. Neither the radial threads nor the hub threads have this glue, allowing the spider easy and rapid access to all parts of its web.

An orb weaver spider

Surreal in color and form, the spiny orb weaver, Gasteracantha cancriformis, builds its web in trees and other tall
vegetation. This genus occurs primarily in the tropics; however, this particular species is also found across the
southernmost states in North America.

Some orb weavers build a web that remains in place for more than one day. Among these diurnal spiders are some that incorporate a special structure into the web, called the stabilamentum. The stabilamentum is composed of a thicker kind of silk, frequently appearing as a conspicuous white area in the web. It may look like a lace doily, or like one or more heavy zigzags in the web. Another type of stabilamentum consists of a line of silk above and below the resting spot in the hub of the web. The empty husks of insect prey are attached to this line, forming irregular clumps of detritus. Sitting motionless in the open spot in the middle of this detritus, the orb weaver Cyclosa appears to be just one more clump of debris in the stabilamentum. Camouflage protects the spider against predation by birds. Yet a different type of protection from birds may be derived from the presence of stabilamenta.

Orb weavers are more flexible in their ability to react to different circumstances than one might imagine. They build larger webs when they are hungry or if they are in areas of low prey availability than when they are well fed or in areas of high prey availability. Both web design and the timing of its construction are synchronized with the type of prey and its availability, requiring the adjustment of the spider’s circadian rhythm. In addition, orb weavers modify their approach to different types of prey in the web depending on whether the prey is potentially dangerous or not. They seem to know what kind of prey has been captured (perhaps based on the vibrations transmitted from its struggles) even before the spider physically makes contact with the prey. Some undesirable prey, such as stinging insects, are deliberately cut loose and released from the web. Other prey, like stink bugs, may be carefully wrapped so as to avoid eliciting a release of defensive chemicals until the killing bite can be administered in safety.

Amazing Arachnids coverAmazing Arachnids
By Jillian Cowles

The American Southwest is home to an extraordinary diversity of arachnids, from spitting spiders that squirt silk over their prey to scorpions that court one another with kissing and dancing. Amazing Arachnids presents these enigmatic creatures as you have never seen them before. Featuring a wealth of color photos of more than 300 different kinds of arachnids from eleven taxonomic orders–both rare and common species—this stunningly illustrated book reveals the secret lives of arachnids in breathtaking detail, including never-before-seen images of their underground behavior.

Amazing Arachnids covers all aspects of arachnid biology, such as anatomy, sociality, mimicry, camouflage, and venoms. You will meet bolas spiders that lure their victims with fake moth pheromones, fishing spiders that woo their mates with silk-wrapped gifts, chivalrous cellar spiders, tiny mites, and massive tarantulas, as well as many others. Along the way, you will learn why arachnids are living fossils in some respects and nimble opportunists in others, and how natural selection has perfected their sensory structures, defense mechanisms, reproductive strategies, and hunting methods.

  • Covers more than 300 different kinds of arachnids, including ones new to science
  • Features more than 750 stunning color photos
  • Describes every aspect of arachnid biology, from physiology to biogeography
  • Illustrates courtship and mating, birth, maternal care, hunting, and defense
  • Includes first-ever photos of the underground lives of schizomids and vinegaroons
  • Provides the first organized guide to macroscopic mites, including photos of living mites for easy reference

Amazing Arachnids: Vinegaroons

Adapted from pages 69-74 of Amazing Arachnids:

Armed with heavy, lobsterlike claws at the front end of their bodies and shooting almost pure acetic acid out of their rear ends, vinegaroons seem to have stepped straight out of a science fiction novel. Despite their fantastic abilities, vinegaroons are perhaps the most poorly understood of the large arachnids. This may be the result of their nocturnal habits, dark nonfluorescent coloration, and the fact that they live most of their lives underground. However, the story of these enigmatic creatures is well worth the cost, albeit paid for in sleepless nights. Their story rivals and even surpasses the creations of fiction.

The common name “vinegaroon” is well chosen. The defensive spray of the vinegaroon Mastigoproctus giganteus of the southwestern United States consists primarily of acetic acid (up to 84 percent), water (10 percent), and caprylic acid (5 percent). Acetic acid is, of course, the component that gives vinegar its characteristic odor. Hydrophilic “water-loving” acetic acid in pure form simply beads up on the lipid-containing cuticle of most arthropods. But with the addition of the lipophilic “lipid-loving” caprylic acid, the spray spreads easily and penetrates into the cuticle. The caprylic acid derives its surfactant properties from a chain of 8 carbon atoms in the molecule, as compared with only 2 carbons contained in acetic acid. The acetic acid spray is produced in a pair of pygidial glands in the abdomen of the vinegaroon. Contraction of muscles in the outer layer surrounding the gland discharges the mixture as a spray from a knoblike structure called the pygidium at the base of the “tail” (called the flagellum). By bending the abdomen and rotating the knob, the vinegaroon can direct the spray with considerable accuracy, even if the target is almost directly in front of it.

As added protection, vinegaroons can defend themselves by spraying almost pure acetic acid from the pygidium, located at the base of the flagellum. By rotating the pygidium, the vinegaroon can aim the spray in almost any direction, even almost immediately in front of it. The flagellum assists the vinegaroon in accurately aiming the spray. Photo by Bruce D. Taubert.

Vinegaroons may spray repeatedly (as many as 19 times) before depleting their reserve of defensive chemicals. It takes about a day for them to recharge their reservoir. The spray has proven to serve as a deterrent to the most formidable arthropod foes such as ants. It also repels vertebrate predators such as the fierce little predaceous grasshopper mice. In contact with human skin, it may cause a burning sensation, and of course the eyes of a potential vertebrate predator such as a bird or a grasshopper mouse would be highly vulnerable to the effects of the acid.

The acetic acid is used purely as a defense weapon—not for capturing prey. A hunting vinegaroon employs tools similar to those used by scorpions for  detecting prey. A combination of sensilla (to pick up substrate vibrations) and trichobothria (to detect airborne vibrations) on the uropygid’s legs allow it to narrow down the general location of its quarry. The tiny hairs on the flagellum might also assist in this task. At the same time, the antenniform legs are extended forward, tapping the surface as the uropygid seeks out prey. Chemosensory hairs on the antenniform legs provide chemical clues as to the identity of any objects it encounters. As soon as the vinegaroon has positively identified a potential prey animal, it charges forward, grabbing with its heavy, clawlike palps. If it misses with the first try, it excitedly feels around with the antenniform legs, searching until it has once again located its quarry.

There are 4 free living instar stages before maturation, and since the young uropygid may not molt following a poor year, it may take from 5 to 7 years to reach maturity. Vinegaroons do not molt again once they are mature, and so their normal lifespan in the wild is probably in the range of 6 to 9 years. Eventually, this magnificent predator slows down due to old age, as joints stiffen and lost appendages cannot be regenerated. Perhaps even in the wild, it may actually die of old age, still a formidable predator to the end.

 

Amazing Arachnids
By Jillian Cowles

The American Southwest is home to an extraordinary diversity of arachnids, from spitting spiders that squirt silk over their prey to scorpions that court one another with kissing and dancing. Amazing Arachnids presents these enigmatic creatures as you have never seen them before. Featuring a wealth of color photos of more than 300 different kinds of arachnids from eleven taxonomic orders–both rare and common species—this stunningly illustrated book reveals the secret lives of arachnids in breathtaking detail, including never-before-seen images of their underground behavior.

Amazing Arachnids covers all aspects of arachnid biology, such as anatomy, sociality, mimicry, camouflage, and venoms. You will meet bolas spiders that lure their victims with fake moth pheromones, fishing spiders that woo their mates with silk-wrapped gifts, chivalrous cellar spiders, tiny mites, and massive tarantulas, as well as many others. Along the way, you will learn why arachnids are living fossils in some respects and nimble opportunists in others, and how natural selection has perfected their sensory structures, defense mechanisms, reproductive strategies, and hunting methods.

  • Covers more than 300 different kinds of arachnids, including ones new to science
  • Features more than 750 stunning color photos
  • Describes every aspect of arachnid biology, from physiology to biogeography
  • Illustrates courtship and mating, birth, maternal care, hunting, and defense
  • Includes first-ever photos of the underground lives of schizomids and vinegaroons
  • Provides the first organized guide to macroscopic mites, including photos of living mites for easy reference

Amazing Arachnids: Jumping Spiders

Adapted from pages 236-247 of Amazing Arachnids:

Jumping spiders have so many pleasing qualities that it would be difficult to decide what is most admirable about these delightful little creatures. Shimmering iridescence and rich, velvety colors equal the beauty of birds and butterflies. Their fearless capture of prey and their acrobatic leaps surprise and astonish us. Their complex courtship song and dance pique our curiosity. But perhaps the most endearing aspect of jumping spiders is their enormous, forward-facing eyes, gazing at us with every appearance of intelligence and inquisitiveness.

These large, forward-facing eyes, called anterior median eyes, are indeed the key characteristic of this diurnal hunter. Jumping spiders locate their prey visually, stalking and pouncing on it like tiny cats. Unlike vertebrate systems in which one pair of eyes handles depth perception, motion detection, and detail resolution, the spider’s 4 pairs of eyes divide these tasks. Collectively, their 8 eyes create a visual system that rivals any other arthropod’s vision.

Habronattus hallani male. This species of
Habronattus is found throughout a large part of the western United States and into Mexico. It is also primarily a ground hunter.

The force of the grip is due to physical adhesion, not to suction cups or electrostatic forces. If two glass slides are overlapped with a thin film of water between them, they are difficult to pull apart because of the capillary force of the water. The scopula hairs of the spider utilize these extremely strong capillary forces. Apparently the water available in the atmosphere and on surfaces provides the necessary thin film for the end feet to grip the surface. This explains why spiders with scopula hairs can walk sure-footedly on vertical surfaces and upside down, even on glass surfaces. In jumping spiders, the tips of the tarsi (feet) have such dense claw tufts of scopula hairs that they appear to have fuzzy “toes.”

Jumping spiders make up the most diverse family of arachnids in the world, with approximately 6,000 species described so far. As one might expect with such diversity, some jumping spiders have evolved behaviors that fill extremely specialized niches. One jumping spider in Africa, Evarcha culicivora, prefers to feed on bloodfilled female mosquitoes, especially mosquitoes of the genus Anopheles, famous for spreading malaria. Another salticid, Phyaces comosus from the bamboo areas of Sri Lanka, specializes in predating the eggs and hatchlings of other jumping spiders. It is so tiny and so closely resembles a bit of dirt or debris that it can sneak into the nest of another jumping spider undetected. Yet another species, Bagheera kiplingi from Central America, has a primarily vegetarian diet—unique in the spider world. It lives in acacia trees that produce little nubbins of protein and fat from their leaf tips, as well as nectar from the base of the leaves. These provide food for the ants that in return guard the tree from caterpillars and other herbivores. The jumping spider steals the nubbins and nectar despite the ant patrols, living almost entirely on this vegetable source of protein.

In conclusion, jumping spiders rival any other group of creatures for their beauty, diversity, and complex behaviors. A combination of natural selection with sexual selection has produced an array of stunningly beautiful and surprisingly intelligent predators. The world is a richer place thanks to these diminutive gems.

Amazing Arachnids
By Jillian Cowles

The American Southwest is home to an extraordinary diversity of arachnids, from spitting spiders that squirt silk over their prey to scorpions that court one another with kissing and dancing. Amazing Arachnids presents these enigmatic creatures as you have never seen them before. Featuring a wealth of color photos of more than 300 different kinds of arachnids from eleven taxonomic orders–both rare and common species—this stunningly illustrated book reveals the secret lives of arachnids in breathtaking detail, including never-before-seen images of their underground behavior.

Amazing Arachnids covers all aspects of arachnid biology, such as anatomy, sociality, mimicry, camouflage, and venoms. You will meet bolas spiders that lure their victims with fake moth pheromones, fishing spiders that woo their mates with silk-wrapped gifts, chivalrous cellar spiders, tiny mites, and massive tarantulas, as well as many others. Along the way, you will learn why arachnids are living fossils in some respects and nimble opportunists in others, and how natural selection has perfected their sensory structures, defense mechanisms, reproductive strategies, and hunting methods.

  • Covers more than 300 different kinds of arachnids, including ones new to science
  • Features more than 750 stunning color photos
  • Describes every aspect of arachnid biology, from physiology to biogeography
  • Illustrates courtship and mating, birth, maternal care, hunting, and defense
  • Includes first-ever photos of the underground lives of schizomids and vinegaroons
  • Provides the first organized guide to macroscopic mites, including photos of living mites for easy reference

Amazing Arachnids: The Lace-Weaver Spiders

Amazing Arachnids is a new, month-long series from Princeton Nature. Each week, we’ll highlight one of the unique arachnids found in Jillian Cowles’ richly illustrated and up-close look at the secret lives of spiders.

Adapted from page 229 of the text: 

Broad, black chelicerae and a stocky build give members of the family Amaurobiidae a powerful appearance suggestive of bulldogs. The imposing physique of these spiders contrasts with the delicate beauty of their webs, built of woolly cribellate silk. These characteristic webs give this family its name “lace-weaver spiders” or “hacklemesh weavers.” The cribellate silk of the web radiates out from a tunnel retreat, where the spider lies in wait. Insects become tangled in these hackled threads, giving time for the spider to rush out from its hiding place and catch the prey.

Amaurobius has a truly remarkable natural history in regard to its reproduction. In the case of Amaurobius ferox (an introduced species from Europe reportedly found in southern California), the mother spider lays her first clutch of eggs and stays nearby to guard them until the babies hatch. This maternal behavior is consistent with many other species of arachnids and is therefore hardly noteworthy. But then it gets interesting. After the spiderlings emerge from the egg sac, they interact with their mother, and she is induced by this interaction to lay a second clutch of eggs. This time, the eggs are laid before they are mature, and consequently this clutch of eggs serves as food for the spiderlings that hatched from the first clutch. This is referred to as trophic egg laying and is a strategy employed by several other species of animals, including some species of poison dart frogs. The spiderlings that receive this food are heavier and have a higher survival rate than spiderlings deprived of the trophic egg meal.

Callobius arizonicus. Callobius are found in cool areas, such as the mountains of Arizona and the forests of California.

But the mother spider’s sacrifice does not end there. The mother and her offspring interact further, and this time she actually appears to solicit her babies to feed on her. This the babies do, collectively killing and feeding on their mother. This matriphagy appears to be regulated by the life stage of the spiderlings, the reproductive state of the mother, and the behavioral interactions of the mother and her young. The spiderlings derive considerable benefit from this behavior. They are heavier and larger at the time they disperse compared with spiderlings deprived of their mother as food, including groups of spiderlings given an abundance of other prey to eat.

Finally, the matriphagous spiderlings have a longer period of social behavior, compared with the nonmatriphagous spiderlings. The subsocial spiderlings live together through several instar stages on the web of their mother, cooperatively killing prey and sharing it. The maternal web appears to provide a superior platform for the offspring to detect and cooperatively kill prey, as compared with webs that the spiderlings construct themselves. Prey that would be too large for one or two spiderlings to overcome is killed by groups of spiderlings, and that prey is shared even with those that did not take part in that particular kill. The spiderlings appear to use coordinated teamwork to subdue prey that is up to 10 times the size of any individual spiderling. Cooperative prey capture increases predation efficiency and survival of all the spiderlings.

Most of the members of the family Amaurobiidae live in cool, moist habitats, making their webs under debris, in caves, or in the nooks and crannies of trees. California boasts the greatest diversity of these spiders in the United States. In the arid southwestern states, Callobius arizonicus lives principally at higher elevations where it is cooler and moister. Found under rocks and dead wood, several individual Callobius spiders may share a single shelter. Only centimeters may separate their webs, indicating some degree of tolerance between individuals of the same species. Also like Amaurobius, Callobius guards her egg sac, which is produced in the shelter of her refuge. But in the case of Callobius, it is unknown whether the mother spider feeds her young.

 

Amazing Arachnids
By Jillian Cowles

The American Southwest is home to an extraordinary diversity of arachnids, from spitting spiders that squirt silk over their prey to scorpions that court one another with kissing and dancing. Amazing Arachnids presents these enigmatic creatures as you have never seen them before. Featuring a wealth of color photos of more than 300 different kinds of arachnids from eleven taxonomic orders–both rare and common species—this stunningly illustrated book reveals the secret lives of arachnids in breathtaking detail, including never-before-seen images of their underground behavior.

Amazing Arachnids covers all aspects of arachnid biology, such as anatomy, sociality, mimicry, camouflage, and venoms. You will meet bolas spiders that lure their victims with fake moth pheromones, fishing spiders that woo their mates with silk-wrapped gifts, chivalrous cellar spiders, tiny mites, and massive tarantulas, as well as many others. Along the way, you will learn why arachnids are living fossils in some respects and nimble opportunists in others, and how natural selection has perfected their sensory structures, defense mechanisms, reproductive strategies, and hunting methods.

  • Covers more than 300 different kinds of arachnids, including ones new to science
  • Features more than 750 stunning color photos
  • Describes every aspect of arachnid biology, from physiology to biogeography
  • Illustrates courtship and mating, birth, maternal care, hunting, and defense
  • Includes first-ever photos of the underground lives of schizomids and vinegaroons
  • Provides the first organized guide to macroscopic mites, including photos of living mites for easy reference

 

Insect of the Week: A Guide to Lightningbug Linguistics

Ever wish you could understand what the fireflies are saying? Well, you can!

The fireflies you’ll see most often in the eastern United States belong to one of the 34+ species of Photinus lightningbugs. These familiar fireflies fill our summer evenings with delight – they’re easy to catch because they fly at a leisurely pace, low above the ground. During summer months, different species make brief appearances, each with a mating season that lasts only a few weeks. Different Photinus species also start their courtship flashing at different times of night: certain species court just at dusk, while others wait until full darkness.

Taxonomically speaking, you need to inspect the male genitalia to really pin down Photinus species identifications. But many species also differ in the pattern and timing of their courtship flashes. So you can learn to distinguish species by paying close attention to the exchange of flash signals between males and females (using a stopwatch will help).

Photinus courtship goes like this: each evening, flying males advertise their availability by broadcasting a species-specific flash pattern. Females, who can fly but generally don’t, sit perched in vegetation and watch for males as they pass by. A females may respond to attractive male by curling her abdomen in his direction and giving him a flash back – it’s her “come hither” sign! When he flies closer and flashes again, they might strike up a conversation. This back-and-forth flash dialog will continue – often attracting other amorous males – until the pair finally meets and mates.

The guide below will help you decipher the distinctive courtship flash patterns given by 11 of our common Photinus species:

Here’s how to read the chart: for each species, the males’ flash patterns are shown in blue, next to the response flashes of their corresponding female (shown in red, note change in time scale).

The top six rows show species where the male flash pattern consists of a single pulse of light that’s repeated at fixed time intervals. You can recognize what Photinus species these males belong to by paying close attention to their flash timing. For instance, Photinus pyralis males give a leisurely flash (about ¾ of a second in duration), which they repeat every 5-6 seconds. In contrast, Photinus marginellus males emit a quick flash (less than ½  a second), and repeat this every 3 seconds.

The next three rows show Photinus species where males emit a double-pulsed flash pattern. Here it’s the time interval between the two pulses that differs among species; this interval ranges from about ½ second in Photinus consanguineus to 2 seconds in Photinus macdermotti. In the last two species males give multiple pulses that vary in the number and interval between pulses.

Female responses are illustrated on the right-hand side of the chart. Look down in the grass for females, and measure how long it takes them to answer a male’s flash. In Photinus marginellus, females will respond almost immediately (within less than a second), while Photinus ignitus females have a response delay of about 4 seconds.

With practice, you can use these flash patterns to recognize many different Photinus species, so step outside and have some fun! You can learn more about these courtship conversations in Silent Sparks: The Wondrous World of Fireflies.

 

silent sparksSilent Sparks
The Wondrous World of Fireflies

For centuries, the beauty of fireflies has evoked wonder and delight. Yet for most of us, fireflies remain shrouded in mystery: How do fireflies make their light? What are they saying with their flashing? And what do fireflies look for in a mate? In Silent Sparks, noted biologist and firefly expert Sara Lewis dives into the fascinating world of fireflies and reveals the most up-to-date discoveries about these beloved insects. From the meadows of New England and the hills of the Great Smoky Mountains, to the rivers of Japan and mangrove forests of Malaysia, this beautifully illustrated and accessible book uncovers the remarkable, dramatic stories of birth, courtship, romance, sex, deceit, poison, and death among fireflies.

The nearly two thousand species of fireflies worldwide have evolved in different ways—and while most mate through the aerial language of blinking lights, not all do. Lewis introduces us to fireflies that don’t light up at all, relying on wind-borne perfumes to find mates, and we encounter glow-worm fireflies, whose plump, wingless females never fly. We go behind the scenes to meet inquisitive scientists who have dedicated their lives to understanding fireflies, and we learn about various modern threats including light pollution and habitat destruction. In the last section of the book, Lewis provides a field guide for North American fireflies, enabling us to identify them in our own backyards and neighborhoods. This concise, handy guide includes distinguishing features, habits, and range maps for the most commonly encountered fireflies, as well as a gear list.

A passionate exploration of one of the world’s most charismatic and admired insects, Silent Sparks will inspire us to reconnect with the natural world.

Insect of the Week: Synchronous Symphonies

Among all the glamorous mating rituals that have been shaped by evolution, the displays performed by certain synchronously flashing fireflies might rank as the most spectacular. For reasons we don’t yet understand, only a few lightningbugs show a remarkable behavior: thousands of male fireflies will match up their rhythms to flash together in unison. Two distinct types of synchronous flash behavior have been observed: one type involves stationary males, while the other takes place among roving (flying) fireflies.

In southeast Asia, certain Pteroptyxmale fireflies sit in communal display trees along tidal rivers, where each night they spend hours flashing together in perfect synchrony. Females fly to these stationary aggregations, known as leks, where mating occurs.

Writing in the journal Science in 1935, Hugh Smith, a naturalist living in Thailand, described these dazzling displays:

Photo credit: Radim Schreiber

Imagine a tree thirty-five to forty feet high thickly covered with small ovate leaves, apparently with a firefly on every leaf and all the fireflies flashing in perfect unison at the rate of about three times in two seconds, the tree being in complete darkness between the flashes. Imagine a dozen such trees standing close together along the river’s edge with synchronously flashing fireflies on every leaf. Imagine a tenth of a mile of riverfront with an unbroken line of Sonneratia[mangrove] trees with fireflies on every leaf flashing in synchronism, the insects on the trees at the ends of the line acting in perfect unison with those between.

 

Because fireflies congregrate so predictably in the same trees, night after night for months, native boatmen once navigated among the twisting waterways using firefly display trees as landmarks.

But stationary flash synchrony doesn’t happen in any North American fireflies. Instead, several of our lightningbug species show a kind of wave synchrony, where flashes are synchronized locally among males flying within line-of-sight of each other. In the southern Appalachians, the synchronous symphony of Photinus carolinusattracts thousands of visitors to admire these flying males as they coordinate their six-pulsed courtship flashes with those of nearby males. These fireflies create waves of synchronous flashing that moves through the forest in the Allegheny National Forest and Great Smoky Mountains National Park. Similar displays of wave synchrony among roving males can be seen in mating displays of Photuris frontalis in Congaree National Park, South Carolina, Photinus knulli in Arizona, and Macrolampis palaciosi in Tlaxcala, Mexico. When they’re in a dense population, males of other fireflies will sometimes synchronize their flashes for a short time.

Wherever you find them, synchronous fireflies make an indelible impression – they are certainly one of Earth’s great natural treasures!

 

Learn more about firefly synchrony in Silent Sparks: The Wondrous World of Fireflies, and on the author’s firefly blog.

silent sparksSilent Sparks
The Wondrous World of Fireflies

For centuries, the beauty of fireflies has evoked wonder and delight. Yet for most of us, fireflies remain shrouded in mystery: How do fireflies make their light? What are they saying with their flashing? And what do fireflies look for in a mate? In Silent Sparks, noted biologist and firefly expert Sara Lewis dives into the fascinating world of fireflies and reveals the most up-to-date discoveries about these beloved insects. From the meadows of New England and the hills of the Great Smoky Mountains, to the rivers of Japan and mangrove forests of Malaysia, this beautifully illustrated and accessible book uncovers the remarkable, dramatic stories of birth, courtship, romance, sex, deceit, poison, and death among fireflies.

The nearly two thousand species of fireflies worldwide have evolved in different ways—and while most mate through the aerial language of blinking lights, not all do. Lewis introduces us to fireflies that don’t light up at all, relying on wind-borne perfumes to find mates, and we encounter glow-worm fireflies, whose plump, wingless females never fly. We go behind the scenes to meet inquisitive scientists who have dedicated their lives to understanding fireflies, and we learn about various modern threats including light pollution and habitat destruction. In the last section of the book, Lewis provides a field guide for North American fireflies, enabling us to identify them in our own backyards and neighborhoods. This concise, handy guide includes distinguishing features, habits, and range maps for the most commonly encountered fireflies, as well as a gear list.

A passionate exploration of one of the world’s most charismatic and admired insects, Silent Sparks will inspire us to reconnect with the natural world.

Insect of the Week: How to Make Your Yard More Firefly-Friendly

silent sparksYour neighborhood might have hundreds of fireflies, or maybe you have just a few. Perhaps you have none at all. No matter which, here are some simple things that will help make any yard more attractive to local fireflies.

Create an inviting habitat:
Fireflies need moisture during all of their life stages (that is, eggs, larvae, pupae and the adult).

  • Let the grass grow longer in parts of your lawn to help the soil hold more moisture.
  • Juvenile fireflies spend up to two years living underground, where they feed on earthworms and snails. If you leave some leaf litter and woody debris in the corners of your yard, this will help larval fireflies—and their prey—to thrive.
  • Female fireflies lay their eggs in moist, mossy places, so preserve any wetlands, streams, or ponds in your neighborhood.

Bring back the night:
Fireflies court using bioluminenscent flashes, so artificial lights that are too bright can interfere with their ability to find mates.

  • When installing or re-thinking your outdoor lighting, use only what you need to get the job done.
  • Use shielded lighting fixtures recommended by the International Dark-Sky Association; these direct light downward, where it’s most useful. Use bulbs as low-wattage as possible to provide just the light you need for safety and security.
  • Try turning off your outdoorlights, or put them on timers, particularly during firefly season.

Reduce pesticide use:
Because juveniles fireflies spend months living underground, they will come into contact with any insecticides spread on lawns and gardens. Broad-spectrum insecticides like malathion and diazinon will kill whatever insects they contact, including fireflies.

  • Consider using organic or least-toxic practices and products on your lawn and garden. Avoid broad-spectrum insecticides – use horticultural oils or insecticidal bacteria like Bt designed to target specific pests.
  • Apply pesticides to treat specific pest problems, never routinely.
  • Don’t use Weed & Feed or similar products that contain 2,4-D, which has been shown to be toxic to earthworms and beetles like ladybugs.

As I describe in Silent Sparks, our scientific understanding of firefly biology and habitat requirements has grown exponentially over the past few decades. Such knowledge now provides a powerful tool for protecting fireflies. And of course, we can all work to preserve and restore the wild places where fireflies thrive – their fields and forests, their mangoves and meadows. We all dream about the kind of world we want our children to inherit. Let’s make certain the magical sparkle of fireflies will continue to be part of their world.

Silent Sparks
The Wondrous World of Fireflies

For centuries, the beauty of fireflies has evoked wonder and delight. Yet for most of us, fireflies remain shrouded in mystery: How do fireflies make their light? What are they saying with their flashing? And what do fireflies look for in a mate? In Silent Sparks, noted biologist and firefly expert Sara Lewis dives into the fascinating world of fireflies and reveals the most up-to-date discoveries about these beloved insects. From the meadows of New England and the hills of the Great Smoky Mountains, to the rivers of Japan and mangrove forests of Malaysia, this beautifully illustrated and accessible book uncovers the remarkable, dramatic stories of birth, courtship, romance, sex, deceit, poison, and death among fireflies.

The nearly two thousand species of fireflies worldwide have evolved in different ways—and while most mate through the aerial language of blinking lights, not all do. Lewis introduces us to fireflies that don’t light up at all, relying on wind-borne perfumes to find mates, and we encounter glow-worm fireflies, whose plump, wingless females never fly. We go behind the scenes to meet inquisitive scientists who have dedicated their lives to understanding fireflies, and we learn about various modern threats including light pollution and habitat destruction. In the last section of the book, Lewis provides a field guide for North American fireflies, enabling us to identify them in our own backyards and neighborhoods. This concise, handy guide includes distinguishing features, habits, and range maps for the most commonly encountered fireflies, as well as a gear list.

A passionate exploration of one of the world’s most charismatic and admired insects, Silent Sparks will inspire us to reconnect with the natural world.

Insect of the Week: Question Marks

Adapted from page 46 of Butterfly Gardening:

Butterfly guides describe the Question Mark as a butterfly found in and at the edges of woodlands, and specifically moist woodlands. Even if your garden does not happen to be ideally situated next to a bucolic, damp, woody wonderland, Question Marks can still be drawn to parks and yards if their caterpillar foods—elms, hackberries, or nettles—are readily available. Since nettles are renowned for stinging, and elms (still susceptible to Dutch elm disease) are not commercially available, you will probably want to check native-plant nurseries for one of the many species of hackberry tree. As a bonus, if you live within their range, a hackberry may also reward you by attracting the less-common butterflies Hackberry and Tawny emperors, Empress Leilia, or American Snout.

A Question Mark (left) and a two Hackberry Emperors share a juicy watermelon slice. Photo credit: Mike Wetherford.

Question Marks rarely visit flowers for nectar; instead, they gain energy by drinking liquids from rotting fruit, tree sap, and even animal droppings. An interesting way to see Question Marks in a garden setting is to set up a butter y feeder, which can be as simple as a slice of watermelon set out on a plate where animals and people will not disturb it. Other gardeners create more elaborate arrangements for butterfly feeding.

Butterfly Gardening: The North American Butterfly Association Guide
By Jane Hurwitz

Butterfly gardening creates habitats that support butterflies, connecting us with some of the most beautiful creatures in the natural world and bringing new levels of excitement and joy to gardening. In this engaging and accessible guide, lavishly illustrated with more than two hundred color photographs and maps, accomplished butterfly gardener Jane Hurwitz presents essential information on how to choose and cultivate plants that will attract a range of butterflies to your garden and help sustain all the stages of their life cycles.

An indispensable resource for aspiring and experienced butterfly gardeners alike, Butterfly Gardening is the most gardener-friendly source on the subject, covering all the practical details needed to create a vibrant garden habitat that fosters butterflies. It tells you which plants support which butterflies, depending on where you live; it describes what different butterflies require in the garden over the course of their lives; and it shows you how to become a butterfly watcher as well as a butterfly gardener.

While predominantly recommending regionally native plants, the book includes information on non-native plants. It also features informative interviews with experienced butterfly gardeners from across the United States. These gardeners share a wealth of information on plants and practices to draw butterflies to all kinds of gardens–from small suburban gardens to community plots and larger expanses.

Whether you are a gardener who wants to see more butterflies in your garden, a butterfly enthusiast who wants to bring that passion to the garden, or someone who simply wants to make their garden or yard friendlier to Monarchs or other butterflies, this is a must-have guide.

  • An essential guide for aspiring and experienced butterfly gardeners
  • Encourages readers to rethink gardening choices to support butterflies and other pollinators in their gardens and communities
  • Introduces gardeners to butterfly watching
  • Includes regional lists of plant species that are time-proven to help sustain butterflies and their caterpillars
  • Features informative interviews with expert butterfly gardeners from across the United States

 

Insect of the Week: Skipper Butterflies

Adapted from page 55-58 of Butterfly Gardening:

Skippers are small, fast-flying butterflies that many people initially think are moths. Skippers have relatively thick bodies and short wings and their flight is often characterized as fast, darting, or jerky—obviously thought by some to be a “skipping” motion.

The vast majority of the skippers in the United States lack colorful scales and so tend to be orange, white, brown, black, or gray. Many skippers are smaller than the familiar and colorful garden visitors that initially come to mind when thinking “butterfly,” but once you notice skippers, you will appreciate the motion and activity they add to the garden.

A Common-Checkered Skipper in a typical spread-wing stance. Photo credit: Alan Schmierer.

Two subfamilies of skippers visit gardens in the United States: spreadwing skippers and grass-skippers. The spreadwing skippers generally perch with both forewings and hindwings open flat, while grass-skippers sit perkily with all wings closed or with the forewings open at a 45-degree angle to the flat hindwings. It is possible to get a peek at the open wings of a grass-skipper when it basks in the sun, a common behavior. Grass-skippers are also equipped with exceedingly long tongues, allowing them to nectar at many types of flowers.

Common Checkered-Skipper is likely the most widespread skipper in the United States, and its caterpillars feed on plants in the Mallow Family. This spreadwing skipper inhabits many different settings, from prairies and meadows to yards and pastures. Open, sunny, often disturbed places are what Common Checkered-Skippers prefer.

Butterfly Gardening: The North American Butterfly Association Guide
By Jane Hurwitz

Butterfly gardening creates habitats that support butterflies, connecting us with some of the most beautiful creatures in the natural world and bringing new levels of excitement and joy to gardening. In this engaging and accessible guide, lavishly illustrated with more than two hundred color photographs and maps, accomplished butterfly gardener Jane Hurwitz presents essential information on how to choose and cultivate plants that will attract a range of butterflies to your garden and help sustain all the stages of their life cycles.

An indispensable resource for aspiring and experienced butterfly gardeners alike, Butterfly Gardening is the most gardener-friendly source on the subject, covering all the practical details needed to create a vibrant garden habitat that fosters butterflies. It tells you which plants support which butterflies, depending on where you live; it describes what different butterflies require in the garden over the course of their lives; and it shows you how to become a butterfly watcher as well as a butterfly gardener.

While predominantly recommending regionally native plants, the book includes information on non-native plants. It also features informative interviews with experienced butterfly gardeners from across the United States. These gardeners share a wealth of information on plants and practices to draw butterflies to all kinds of gardens–from small suburban gardens to community plots and larger expanses.

Whether you are a gardener who wants to see more butterflies in your garden, a butterfly enthusiast who wants to bring that passion to the garden, or someone who simply wants to make their garden or yard friendlier to Monarchs or other butterflies, this is a must-have guide.

  • An essential guide for aspiring and experienced butterfly gardeners
  • Encourages readers to rethink gardening choices to support butterflies and other pollinators in their gardens and communities
  • Introduces gardeners to butterfly watching
  • Includes regional lists of plant species that are time-proven to help sustain butterflies and their caterpillars
  • Features informative interviews with expert butterfly gardeners from across the United States

 

Insect of the Week: the Great Spangled Fritillary

Adapted from pages 85 to 87 of Butterfly Gardening:

The Great Spangled Fritillary is a large, showy butterfly found throughout a large section of the United States from southern Canada down to northern California on the western half of the continent, with the range extending down across the country to North Carolina on the East Coast. Within its range, the Great Spangled Fritillary can be considered a common garden butterfly that is on the wing during the summer months and through the early fall.

Violets are the only plant that Great Spangled Fritillary caterpillars will eat. Great Spangled Fritillaries do not care whether the violet flowers are blue, yellow, or white, though it does matter to egg-laying butterflies that the violets are native. African “violets,” which are grown as houseplants, and pansies, which are sold at garden centers as outdoor bedding plants, are not suitable for Great Spangled Fritillary caterpillars. Since most violets spread enthusiastically, you may regard them as weeds or wildflowers, but native violets are the kind needed to feed Great Spangled Fritillaries as well as a number of other fritillary species that have smaller ranges.

A Great Sprangled Fritillary laying eggs near a violet. Photo credit: Jane Hurwitz

Butterflies bearing the common name “fritillary” can be confusing; since they all share a name, one could conclude that they all belong to the same genus, and therefore share similar characteristics. But things are not that tidy in the butterfly world, or in the gardening world either, and the fritillaries mentioned so far are actually all a bit different.

Great Spangled Fritillary belongs to the genus Speyeria. They have one brood per year and their caterpillars eat only violets. Hosting Great Spangled Fritillaries requires gardeners to hold off on vigorous flowerbed cleaning in the fall. By leaving leaf litter undisturbed surrounding violets, gardeners preserve caterpillar overwintering habitat, ensuring that any unseen caterpillars are able to remain near violets and complete their life cycle. Since Great Spangled Fritillary produces only one generation per year, if your yard is cleared each fall and spring by landscape crews, or by overenthusiastic family members sent outside on a fine fall day, the potential to lose overwintering caterpillars is high.

 

Butterfly Gardening: The North American Butterfly Association Guide
By Jane Hurwitz

Butterfly gardening creates habitats that support butterflies, connecting us with some of the most beautiful creatures in the natural world and bringing new levels of excitement and joy to gardening. In this engaging and accessible guide, lavishly illustrated with more than two hundred color photographs and maps, accomplished butterfly gardener Jane Hurwitz presents essential information on how to choose and cultivate plants that will attract a range of butterflies to your garden and help sustain all the stages of their life cycles.

An indispensable resource for aspiring and experienced butterfly gardeners alike, Butterfly Gardening is the most gardener-friendly source on the subject, covering all the practical details needed to create a vibrant garden habitat that fosters butterflies. It tells you which plants support which butterflies, depending on where you live; it describes what different butterflies require in the garden over the course of their lives; and it shows you how to become a butterfly watcher as well as a butterfly gardener.

While predominantly recommending regionally native plants, the book includes information on non-native plants. It also features informative interviews with experienced butterfly gardeners from across the United States. These gardeners share a wealth of information on plants and practices to draw butterflies to all kinds of gardens–from small suburban gardens to community plots and larger expanses.

Whether you are a gardener who wants to see more butterflies in your garden, a butterfly enthusiast who wants to bring that passion to the garden, or someone who simply wants to make their garden or yard friendlier to Monarchs or other butterflies, this is a must-have guide.

  • An essential guide for aspiring and experienced butterfly gardeners
  • Encourages readers to rethink gardening choices to support butterflies and other pollinators in their gardens and communities
  • Introduces gardeners to butterfly watching
  • Includes regional lists of plant species that are time-proven to help sustain butterflies and their caterpillars
  • Features informative interviews with expert butterfly gardeners from across the United States

 

Jane Hurwitz on Butterfly Gardening

Butterflies are regarded by many as canaries in our ecological coal mine: they provide visual signals indicating the relative health and diversity of a habitat. Improving our local fragmented and degraded habitats in order to promote butterflies may seem like an onerous task, but in Butterfly Gardening: The North American Butterfly Association Guide, Jane Hurwitz presents simple steps to create more vibrant and dynamic environments that encourage wild butterflies to flourish—and provide gardeners of all levels with inspiration and pleasure.

Why did you write this book?

I am a life-long gardener who has had the good fortune to work for an organization that actively promotes gardening for butterflies. During the years I directed the North American Butterfly Association’s Butterfly Garden and Habitat Program,  I was exposed to a wealth of information on butterfly gardening that changed the way I view all aspects of gardening. A large part of my work with the program involved daily communication with people of all skill levels concerning their NABA certified gardens. In fact, the second half of the book revolves around specific butterfly gardeners living in different regions of the United States; there is so much to be learned from other gardeners regardless of their location or garden size.

Writing this book allowed me to explore the connection between how we take care of our landscapes, whether our private gardens or public spaces, and how those choices impact butterflies. Very little is static in a garden, a fact that is accentuated when butterflies—or any insects, for that matter—become part of the garden’s focus. Butterfly gardening is a gardening method that allows the interplay between the natural world and human-made habitats to expand in ways that allow wildlife to flourish. Learning the interconnections between plants and butterflies is fascinating and works as a catalyst to deepen our connection to our natural surroundings. The creation of habitats for butterflies is an ongoing process, not a fixed point that will ever be perfectly attained; as such, butterfly gardening provides an open ended opportunity for constant experimentation and learning.

Who is this book for?

Anyone with an interest in butterflies and gardening—even if they’re only mildly curious! Gardening books are often quite prescriptive, providing chapter after chapter on how to grow specific plants or how to achieve a particular garden style. Butterfly Gardening takes a more flexible approach, imparting basic information on butterfly and plant biology, butterfly watching, and plant selection in an accessible way that allows the reader to make their own informed choices on how best to create a habitat for butterflies within the constraints of their location and budget. Whether one’s focus is on creating habitat for monarchs, installing a school garden, or simply making a suburban yard more butterfly-friendly, once equipped with the essential information it is easy to implement changes that will lure these beautiful and fascinating creatures into our lives.

What are some of the first steps in creating a great butterfly garden?

Eliminating the use of pesticides, particularly those in the class of insecticides known as neonicotinoids, is the first item on any butterfly gardening checklist. Of course, there may need to be exceptions; if my home has termites, for example, I am probably going to need to use pesticides, but as a general rule they are best avoided. In fact, taking pesticides out of our garden toolkits is one of the very few things we must do in order to provide a habitat for butterflies.

Identifying the butterflies that are common to your locale and learning their names would be a second step to consider. There are many ways to accomplish this; some people start with a butterfly guide book and work from their own observations, while others find information through local sources such as nature centers, NABA chapters, or the Extension Service.

Learning the names of butterflies will enable you to communicate better with other butterfly gardeners and will also inform you about which caterpillar food plants to install. Many butterfly gardeners, however, skip this step, at least in the early stages. For many, butterfly gardening begins with the plants (and there are so many good ones!); rather than identify possible butterfly visitors to their garden and plan specifically for that group, they jump right into planting nectar sources, and see what comes to visit. As I emphasize throughout the book, there are no rules about how to start or organize a butterfly garden, but most gardeners do eventually become interested in naming their butterfly visitors and learning about their life cycles.

What would you say is the benefit of butterfly gardening?

A garden represents different things to different people. By using the methods detailed in Butterfly Gardening, a layer of ecological relevance can be added to a pleasurable and revitalizing activity. We can make our gardens a refuge for butterflies as well as ourselves.

 

Jane Hurwitz  is the editor of Butterfly Gardener magazine and the former director of the Butterfly Garden and Habitat Program for the North American Butterfly Association. She lives in northern New Jersey.