Posts Tagged ‘Insects-and-Spiders’

Jumping Oak Galls

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Wednesday, December 19th, 2012
Jumping Oak Galls

Jumping Oak Galls © Julie Craves

Jumping Oak Galls by Julie Craves

A move to a new house has been responsible for my lack of productivity here the last few months. Now that we are settled in, we are anxious to get to know our large property. We have eight acres of wet woods, and while my bark identification skills are serviceable, I’ve been spending more time looking down at the ground to unlock some of the secrets of the forest we will now stewards.

Many of the mature trees are Black Cherry, Bur Oak, and Swamp White Oak. I noticed that many of the fallen oak leaves were pocked with dozens, if not hundreds, of round lesions, each the size of a pinhead. On the uppersides of the leaves, they looked just like pimples. On the underside, each lesion was a shallow pit that was either empty or had a tiny nodule nestled in it.

Those nodules are galls, created by very minute wasps in the genus Neurotarus. They’re known as jumping oak galls, because when the galls detach from the leaf and fall to the ground, the wasp larva inside will sometimes wiggle around and cause the gall to move. The fully developed wasp larvae will overwinter in their galls on the ground. Galls that remain on the leaves are probably doomed – they’ll either dry up and die, will expire because they have been parasitized or their galls have been invaded by insect inquilines, interlopers that feed on the gall tissue.

If all goes well, these galls will produce the all-female generation. Neurotarus wasps, like many of the others in their family, have elaborate life cycles that include alternating asexual and sexual generations.

Members of this family of wasps are quite host-specific, usually attacking only one or a few species of oaks; none use hosts in both the red and white oak groups. All the gall-bearing leaves I found were white oaks, with none on the plentiful red oaks present on the upland parts of the property.

How to Photograph Really Large Spiders (If You’re an Arachnophobe)

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Monday, November 26th, 2012

Huntsman Spider © Jungle Pete

How to Photograph Really Large Spiders (If You’re an Arachnophobe) by Jungle Pete Corradino

This is a Huntsman Spider.

The Huntsman Spider is a very large spider. This is not a good photograph of a spider.

1)    If the spider is in your home, make sure you have created an escape/panic/freak out route. Open a sliding glass door. Blow out candles. Pick babies up off the floor.

2)    If you intend to dispatch the subject after the shoot, make sure your method of destruction is suitable for your enclosure. Baseball bats, whether aluminum or wood are inappropriate.

3)    Use a tripod with a remote to avoid violent, nervous shaking.

4)    Consider a fast shutter speed and a zoom lens to stay as far away as possible.

5)    Kill first, ID later is not an option with spiders. They curl up or even disintegrate. Respect nature. Escort the natives outdoors. Humanely dispatch the invasive species.

The Huntsman is an invasive species, native to Asia and now found throughout the Gulf States and California. Their colloquial name is “Banana Spider”, having most likely arrived in the U.S. with banana imports. They are often confused with Nursery Web Spiders (Pisaurina mira) and the infamous Brown Recluse (Loxosceles recluse) which can inflect a seriously harmful bite. The Huntsman is distinguished from similar spiders by brown “false eyes” on the cephalothorax.

Huntsman Spider © Jungle Pete

The female Huntsman Spider (Heteropoda venatoria) has a body nearly an inch long and carries a white egg sack underneath the body. Both males and females have hairy legs that make the arachnid the size of an average man’s hand. They are ruthless hunters and are valued for their appetite for roaches. The preference is to have them as the first line of defense on the outside of your house.

This one must have hitched a ride down from the attic with the Christmas ornaments. My wife came into my home office, held up eight fingers and pantomimed tiptoeing. I interpreted this to be “it’s eight o’clock, be quiet and don’t wake the baby.” Nope. Eight-legger in the ceiling corner of the bathroom.

The Huntsman has been known to inflict humans with a bite that resembles a harsh bee sting. It’s better if they’re outdoors. This one had three strikes against it. I don’t like hairy-legged spiders. It’s an invasive species. It’s in my house.

The Huntsman is a speedy little devil and any time wasted on photographic endeavors could result in its escape. I have no interest in allowing a hand-sized, biting spider free in my home with my child. So I snapped a quick picture of the beast gobbling the half dollar-sized “good” house spiders before “capturing” it with a web broom. In this case the Huntsman became the hunted.

Generals on the March

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Tuesday, November 20th, 2012
Horse Lubber Grasshopper

Horse Lubber Grasshopper © Sheri Williamson

Generals on the March by Tom Wood and Sheri Williamson

A generous late summer “monsoon” season in the desert grasslands of the Southwest translates to a fall population boom for many wildlife species. Some of the “boomers” are easier to see than others, including the gigantic grasshoppers known as Horse Lubbers. They’re one of the two largest grasshoppers in North America (the other being the Eastern Lubber). A mature female may be 2.75 inches in length and weigh as much as three male Black-chinned Hummingbirds!

Many of our human neighbors here in southeastern Arizona know the Horse Lubber as the “Mexican General,” a colloquial name inspired by its bold pattern of bright yellow accents on a background of black and dark green, like a high-ranking officer in full dress uniform. Grasshoppers often have colorful hindwings, and a few are quite colorful on close inspection (the Rainbow Grasshopper, for example), but no other grasshopper in the Southwest is as in-your-face conspicuous as the Horse Lubber.

Like many desert insects, Horse Lubbers depend on the short-term abundance of food resulting from the late summer rains. When “monsoon” thunderstorms transform the desert into a virtual all-you-can-eat salad bar, lubber nymphs hatch from eggs laid the previous year and begin to gorge themselves. As they reduce the food supply in one area, they march on to greener pastures, passing through several instars (growth stages) as they go. Early instars are chunky and wingless. By the final stage, they have slimmed down and grown wings for greater mobility.

The lubber boom might seem to be a boon for predators, but it pays to be suspicious about a critter that’s abundant, conspicuous, and easy to catch. You’ve probably already figured out that the gaudy attire and sluggish behavior of Horse Lubbers are aposematic, a warning to potential predators of well-armed prey. Like Monarchs and Pipevine Swallowtails, the big ‘hoppers are infused with toxic chemicals that make them unpalatable, but making a predator nauseous is a Pyrrhic victory. The preferred outcome is not to get eaten in the first place. Threatened lubbers start by hissing and flashing their bright salmon-red hindwings. If that doesn’t work, they’ll spray their attackers with noxious chemicals, like six-legged skunks. It doesn’t take too many such encounters for predators to learn not to mess with lubbers. Our pet chickens enthusiastically chase after any small, cryptically colored grasshoppers that find their way into our yard, but they give the big black ones a wide berth.

We think of grasshoppers as herbivores, but Horse Lubbers like a little meat in their diet. They’re not fussy; carrion is fine fare, and they’re not above cannibalism. As with skunks, the sluggish and fearless behavior of lubbers makes them vulnerable to traffic. Those that don’t make it across the highway may become “road food” for their traveling companions. In fact, their chemical defenses are so successful that about the only animal that can stand to eat a Horse Lubber is another Horse Lubber. As our collegue Pete Corradino discovered, Loggerhead Shrikes in Florida will eat Eastern Lubbers after letting them “mellow” a bit to break down the toxins, but we haven’t observed this behavior in Arizona. Maybe Horse Lubbers are “spicier” than their southeastern cousins?

All We Have To Fear…

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Monday, October 29th, 2012

All We Have To Fear © Jungle Pete

All We Have To Fear… by Jungle Pete Corradino 

Arachnids with web spinning architectural prowess
Long-legged daddies with eight legs more or less
Brown furred mammalians with leathery wings
These are a few of my favorite things

Snakes striped with colors that will kill-a-fella
Turtles accused of passing salmonella
Poisonous ivy that desperately clings
These are a few of my favorite things

Aquatic finned creatures with razor sharp gnashers
Thundering, bumbling, honeycomb crashers
Well armored grubbers with nine banded rings
These are a few of my favorite things

When people fear them
When they kill them
This makes me mad
Please would you respect my favorite things
And then I don’t feel so bad

Did You Know: Creepy Crawlers

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Sunday, October 21st, 2012

Did You Know: Creepy Crawlers

Daring Jumping Spider

Daring Jumping Spider © Ken Meyer

  • Did you know that jumping spiders can propel themselves for distances up to 50 times their body length! Mix this with their 360-degree viewing ability with eyes on the backs of their heads and you have one spider that you don’t want to mess with!
  • The Australian funnel-web spider is infamous for its venom that can kill a person in less than an hour and for its sharp fangs that can bite through a shoe!
Black Widow Spider

Black Widow Spider Male, and female © James H. Robinsons

  • Did you know that when spiders are born, they have almost no coloring making them nearly invisible? You better keep your eyes peeled for these creepy crawlers!
  • Did you know that bats have colonized nearly every type of ecosystem on earth, taking residency on all continents except Antarctica?
  • The biggest single gathering of bats in the world is in San Antonio, Texas, where 20-40 million Mexican free-tailed bats pour out of Bracken Cave each night in search of food!
Hairy-legged Vampire Bat

Hairy-legged Vampire Bat

  • Did you know that some bats, including the vampire bat, really do feast on the blood of animals, including humans!
  • Scientists have found an almost perfectly preserved spider fossil in China dating back to the middle Jurassic era, 165 million years ago. The fossilized spiders, Eoplectreurys gertschi, are older than the only two other specimens known by around 120 million years.
Brown Recluse Spider

Brown Recluse Spider © Steven J. Prchal

  • Out of 34,000 species of spiders in this world, only 27 have the power to kill a human with their venom.

Japanese Giant Hornet

  • Whatever you do, avoid contact with a Japanese Giant Hornet. This hornet is the size of your thumb and sprays flesh-melting poison which also acts as a pheromone to attract other hornets from the hive to come and sting you until you are no longer alive.
  • Colonies of soldier ants, which can be up to one million strong, are infamous for dismantling anything living that crosses their path, regardless of its size; they have even been known to take down horses in the Amazon Basin.

Why Does the Cricket Sing?

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Tuesday, October 2nd, 2012
House Cricket

House Cricket © James H. Robinsons

Why Does the Cricket Sing? by Mary Holland

An early fall evening presents us with a symphony of songs emanating from fields far and wide. Most of the musicians are crickets, which are considered more musical than their close relatives, katydids, or their more distant cousins, grasshoppers. Instead of a raspy song, crickets produce melodic chirps. We don’t see these musicians as frequently as we do grasshoppers, as they are nocturnal and, although most of the adults have wings and are capable of flying, they rarely do, making them much less conspicuous.

The surprising thing about the cricket’s song is that crickets produce it by rubbing their wings against each other. At the base of the left forewing (most insects have two pairs of wings, one in front of the other) there is a very thick vein, or rib. The edge of this rib is serrated, with 50 to 300 minute ridges (the number depends on the species). There is a hard scraper on the right forewing. When the cricket raises its wings and rubs the rib against the scraper, a chirp is produced; this process is called stridulation. As the cricket stridulates, the membranes of its wings vibrate, amplifying the sound. Like birds and frogs, male crickets do the singing, with each species producing a slightly different song, recognizable to other crickets as well as entomologists.
The reason it is important for other crickets to recognize their own species’ song is that stridulation is the means by which male crickets attract females in order to mate. Because most of their courtship takes place in the dark, their song is a crucial part of it. Crickets lack ears on their head, but are capable of hearing another cricket’s song thanks to a membrane located on each front leg, visible just below the “knee” joint.

Crickets, like all other insects, are cold-blooded and thus, are the same temperature as their surroundings. Generally, the speed of the song reflects this temperature. The hotter it is, the more rapid the chirps. There is even one species, the snowy tree cricket, whose chirp-frequency allows you to calculate the temperature. Simply count the number of chirps in 15 seconds, add 40 to that number, and you have the temperature degrees Fahrenheit.

Mission: Impossible – the Ground Beetles

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Tuesday, September 4th, 2012

Mission: Impossible – the Ground Beetles by Jungle Pete

Pasimachus ground beetle

Pasimachus ground beetle © Jungle Pete

My mother, a park ranger, once held out a cone from an unknown tree and asked a state forester if he knew which tree it came from. “Some kinda conifer”, he answered, as if that was sufficient. He wasn’t wrong. The cone did come from a coniferous tree, but the answer was as helpful as saying “food” when someone asks “what’s for dinner?”

My mother was hoping for the specific tree. Did the forester know the answer or not?  I hardly know anything and nature proves that to me daily with new mysteries. For example, why one morning was there a Ground Beetle hanging from a web-like snare from the bumper of my car? These are large, hefty beetles. Who caught it? And what type of beetle is it? I’ll give you a hint. You’re not going to find out because I don’t know.

I asked an insect nerd, I mean entomologist, which species it might be and considering there are over 425 different species of ground beetles, I was content to have it narrowed down to the Pasimachus, a genera with at least five indigenous species in Florida. From there he said it was impossible to tell with the photograph provided.

Pasimachus ground beetle

Pasimachus ground beetle © Jungle Pete

Most of the 40,000+ beetles in the world have hardened elytra that cover over and protect the wings. The Pasimachus ground beetles are flightless and the elytra are fused into a firm shell. They spend their time on the ground, in and under logs and leaf litter foraging for caterpillars, other larvae and other ground insects.

How this beetle came to be ensnared, flailing its limbs in the breeze like Ethan Hunt on a mission is beyond me. If it was trapped in a spider’s web, I wasn’t curious enough to look up under my car to find out which kind.

It would have been nice to offer you a genus and species name, but the beetle biologist took me as far as I could go. “Some kinda Pasimachus” would have to do. Sometimes identifying insects is a mission: impossible.

Gypsy Moths

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Thursday, August 23rd, 2012

Gypsy Moths in Manitoba by Gene Walz

Gypsy Moths

Gypsy Moths © E. R. Degginger/Color-Pic, Inc.

My yard was supposed to be sprayed overnight. I live in one of the two areas of Winnipeg where Gypsy Moths (Lymantria dispar) have recently been found. How they got here is anybody’s guess.

We’re proud of our motto, “Friendly Manitoba”, but we’re treating these newcomers in a most hostile manner. A crop-duster full of the insecticide Btk (Bacillus thuringiensis) was supposed to douse my neighborhood. A thunderstorm, heavy winds, and rain gave us a temporary reprieve from last night’s scheduled spraying. The crop-duster never showed up. By the time you read this, it will have given my yard a bacterium bath.  Ah, well.

Btk is said to be “a naturally occurring bacterium that only kills caterpillars.”  I hope so. Since the city started wholesale spraying for mosquito and inchworm prevention, many of the formerly common birds here have disappeared. No more orioles, wrens, or mourning doves in my yard. I miss their songs.

The Gypsy Moth is one of North America’s worst introduced pests. We can thank a misguided scientist named Leopold Trouvelot of Medford, Massachusetts for importing the moths from their native Asia in 1868. Since then the caterpillars have wreaked havoc on forests across the continent, defoliating trees at alarming rates.

I hope this regime of treatments is effective. I don’t want Gypsy Moths in my world. I want my trees to thrive. I don’t want a second round of spraying next year or a third. I want more birds around. They’ve got enough to cope with already.

My Dirt is your Disguise – Insects

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Friday, August 10th, 2012

My Dirt is your Disguise – Insects by Julie Craves

Okay, so domestic chores are not one of my strong points. Yet it was alarming to see a dirty bit of crud in the foyer begin to move under its own power across the entryway. Had I neglected housecleaning for so long that dust bunnies were becoming living organisms, like some Far Side cartoon?

A closer look revealed the animated detritus was an immature Masked Hunter (Reduvius personatus), a true bug inadvertently introduced from Europe sometime before 1900. They are now found over much of the U.S., most frequently being found in the central and northeastern states. They prefer dry conditions, so they are often found indoors. We have found them near doorways and on the front porch, where they hang out to feed on the insects attracted to the lights.

As do other members of the genus, the immature stages of the Masked Hunter look like smaller versions of the adults, except they are covered with fine hair-like structures which collect dust, dirt, and lint (adults are sleek and black). This camouflage perhaps helps the youngsters sneak up on their prey.

Like other assassin bugs, Masked Hunters stab their insect prey with beak-like mouth parts, then inject chemicals that both subdue the victim and liquefy their innards for easy slurping. While small – under an inch – Masked Hunters can nonetheless inflict a painful poke to humans if they are mishandled. They’re benign, though, and don’t transmit any diseases. In fact, they are often considered pretty good housemates. Masked Hunters are mainly nocturnal, and bed bugs are a favorite food, accounting for their alternative name “masked bed bug hunter.”

Bed Bugs Insects

Bed Bug © Will Ferguson

I’m happy to report we don’t have bed bugs, and I’m okay with allowing these little predators to keep the foyer and porch free of other insect invaders. Since covering themselves with debris only improves their hunting prowess, I’ve decided to put off the dusting for just a little while longer…

House of Frass – Insects

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Friday, July 27th, 2012

House of Frass – Insects by Julie Craves

We are long overdue in painting the exterior of our house. Not only would we like to sell it in the next year or two, but of course we feel how our house looks reflects upon us. And “shabby,” “peeling,” and “fading” are not how we like to describe ourselves.

Things could be worse. Let’s say we were the larvae of one of the Cryptocephalinae, or case-bearing leaf beetles. Our “home” (the case) would be made from our own excrement. We all know the longer we live in a house, the more crap we accumulate. In the case of these beetle larvae, this true in a very literal sense. Toting around an abode made of your own turds is a good way to be unobtrusive to predators while in a vulnerable state – or completely unappealing if discovered. In many species, the adult beetles are quite attractive, reward for spending the beginning of their lives covered in their own waste.

Canada Thistle Wildflowers

Canada Thistle © Ron Austing

Some members of another subfamily of leaf beetles follow a similar lifestyle, such as the tortoise beetles. These insects don’t construct quite as solid a structure, but nonetheless do create external self-protection. We recently came across some Thistle Tortiose Beetles (Cassida rubiginosa) on Canada Thistle (Cirsium arvense); neither species is native to North America. Most of the beetle larvae were festooned with frass (the official term for insect poop). Some were not, and looked like spiny trilobites. Either way, creepy.

Green Lacewings Insects

Green Lacewings © Edward S. Ross

The larvae of insects in a completely different family, the Green Lacewings (Chrysopidae) also have spiny exteriors and decorate themselves with debris. These predatory larvae are a bit more catholic in their use of materials. There may be some frass, but usually they use bits of plants and body parts of recent victims. In any event, all of these mobile homes serve as disguise or protection or both.

Many insects utilize convenient substances in the creation of temporary housing. These are just a few examples of the ones that are making do by making doo.