Archive for the 'Insects, Fish, Frogs' Category

Sep 20 2016

The Biggest Die First

Large swordfish on deck during long-lining operations (photo by Derke Snodgrass via NOAA Photo Library)

Large swordfish on deck during long-lining operations (photo by Derke Snodgrass from NOAA Photo Library)

It happened to land animals. Now it’s happening in the ocean.  The biggest die first.

Based on Earth’s current extinction rate of 1,000 times the normal background rate (predicted to become 10 times worse) scientists believe we’re at the start of the sixth mass extinction.

Stanford geoscientist Jonathan Payne wondered if the traits of extinct marine animals could predict the likelihood of extinction in today’s ocean organisms. For mollusks and vertebrates Payne and his colleagues compared ecological traits such as habitat preference and body size in past extinct and present threatened genera (genus: one level above species).  The results were surprising.

In past extinctions habitat preference was a good predictor that an animal would disappear.  That’s not the case now. In this era, the best predictor of future extinction is large body size.

The difference is us.  Human hunting pressure is driving ocean extinction.  Our demand for seafood is high (there are billions of us to feed) and we’ve become very efficient at capturing the largest fish.  Highly migratory predators like the Pacific bluefin tuna have declined precipitously.

We’ve seen this before.  At the end of the Ice Age, as human population expanded across the globe, the megafauna simultaneously went extinct.  It’s now known that sabretooth tigers, giant armadillos and woolly mammoths disappeared due to human hunting.

Woolly mammoth statue in the Royal BC Museum, Victoria, BC, Canada (photo from Wikimedia Commons)

Woolly mammoth statue in the Royal BC Museum, Victoria, BC, Canada (photo from Wikimedia Commons)

We humans are successful because we make tools and hunt cooperatively.  Of course we kill the largest prey first. One large animal feeds more people.

Unfortunately we don’t know when to stop.

 

Read more about Payne’s study here at Science Daily.

(photo of swordfish from NOAA Photo Library. photo of woolly mammoth statue in Royal BC Museum, Victoria, Canada via Wikimedia Commons. Click on the images to see the originals)

p.s. A word about the swordfish pictured above:  Swordfish are highly migratory predators whose population is in danger — or unknown — in many oceans around the world.  In 1998 the North Atlantic population dropped so low that fishing was suspended.  A 2009 international assessment of North Atlantic swordfish showed they had recovered in U.S. fishing areas, so fishing has resumed.  Note: The fishermen who lost their lives aboard the Andrea Gail in The Perfect Storm were longline fishing for swordfish.)

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Sep 17 2016

Honeybee Knickers

Published by under Insects, Fish, Frogs

Honeybee with pollen bags on his legs (photo by Kate St. John)

Honeybee with pollen bags on his legs (photo by Kate St. John)

Honey bees are busy right now collecting nectar and pollen to get them through the winter.  They carry nectar to the hive by swallowing it.  They carry the pollen in sacs on their legs.

According to Wikipedia, the bee’s pollen basket or corbicula is “a polished cavity surrounded by a fringe of hairs.”  Each bee grooms the pollen off her body and stores it in her pollen baskets. Here’s how:

A honey bee moistens its forelegs with its protruding tongue and brushes the pollen that has collected on its head, body and forward appendages to the hind legs. The pollen is transferred to the pollen comb on the hind legs and then combed, pressed, compacted, and transferred to the corbicula on the outside surface of the tibia of the hind legs.

This honeybee’s pollen basket is so big that it looks like she’s wearing orange knickers.

 

(photo by Kate St. John)

p.s. for my British readers:  The word “knickers” in the U.S. is short for “knickerbockers,” the baggy trousers tight at the knee formerly worn by golfers.

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Aug 30 2016

Tiny Emperors

Published by under Insects, Fish, Frogs

Tawny emperor caterpillars (photo by Kate St. John)

Tawny emperor caterpillars (photo by Kate St. John)

Ten days ago Marcy Cunkelman flipped over a leaf and showed us two hundred tiny emperors.

The squiggly green lines are caterpillars of the Tawny Emperor butterfly (Asterocampa clyton) eating the mature leaves on a hackberry tree. They also feed on other trees in the elm family (Celtis).

At this stage the caterpillars huddle and move together for protection but after the third instar they travel alone.

Eventually each caterpillar spins a cocoon and pupates into a butterfly that looks like this:

Tawny emperor butterfly (photo from Wikimedia Commons)

Tawny emperor butterfly (photo from Wikimedia Commons)

The butterflies don’t visit flowers. Instead they feed on rotting fruit, dung, carrion and tree sap … an odd feast for an emperor.

 

(photo of caterpillars by Kate St. John, photo of butterfly from Wikimedia Commons)

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Aug 21 2016

Butterfly With a Birthday Cake

Published by under Insects, Fish, Frogs

Butterfly with a birthday cake (photo by Dana Nesiti)

Butterfly with a birthday cake (photo by Dana Nesiti)

Dana Nesiti (who usually takes photos of bald eagles) has been experimenting with insects.  This one caught my eye.

Is this butterfly celebrating its birthday with 16 candles?

Well, no.  The birthday cake is actually a black-eyed susan with stamens.

And the butterfly is a wild indigo duskywing.

 

Thanks to Dana Nesiti for the cool photo and butterfly identification.

(photo by Dana Nesiti)

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Aug 15 2016

Found A Big Cat

Published by under Insects, Fish, Frogs

Caterpillar of the Promethea moth, twig held by Ramona Sahni (photo by Kate St. John)

Caterpillar of the Promethea moth, twig held by Ramona Sahni (photo by Kate St. John)

On August 6 at Jennings Prairie we found a big green “cat” with a yellow face.  Ramona Sahni held the twig while I took the caterpillar’s picture.

Dianne Machesney later identified it as the larva of a Promethea moth (Callosamia promethea).  He’s named for Prometheus, a Titan in Greek mythology who was a clever trickster and benefactor of mankind.

Nowadays “Promethean” means “boldly creative, defiantly original” — and because he was a Titan, “big.”  The adult male and female moths show off these qualities.

Male Promethea moth (photo from Wikimedia Commons)

Male Promethea moth (photo from Wikimedia Commons)

 

Female Promethea moth (photo from Wikimedia Commons)

Female Promethea moth (photo from Wikimedia Commons)

 

It’s amazing that they look so different.

Big, bold, defiantly original.  No wonder these moths are Promethean.  😉

 

(caterpillar photo by Kate St. John. Moth photos from Wikimedia Commons. Click on the images to see the originals)

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Aug 11 2016

TBT: Watch Out Guys!

Published by under Insects, Fish, Frogs

Praying Mantis (photo by Marcy Cunkelman)

Praying Mantis (photo by Marcy Cunkelman)

On Throw Back Thursday (TBT):

Why is it so dangerous to be a male praying mantis?  Find out in this article from August 2010: Watch Out Guys!

 

(photo by Marcy Cunkelman)

 

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Aug 10 2016

Tree Crickets Tune Their Ears

Published by under Insects, Fish, Frogs

Bug noise is everywhere on hot summer nights. Some of the singers are tree crickets.

Tree crickets (subfamily Oecanthinae) live on every continent except Antarctica.  Camouflaged to match their habitat, these long, skinny, nocturnal insects live in trees and shrubs where they eat just about anything. They’re especially fond of aphids.

Male tree crickets “sing” to attract a mate by rubbing the ridges of their wings together, shown in the video above.   The females don’t sing but they certainly listen.  Each species has a distinctive range of frequencies.  The ladies ignore the cacophony of other species. They only listen for their own.

Because insects are cold-blooded they move slower in cold and faster in heat, so they trill faster when the weather’s hot.  This means the frequency, and thus pitch, of their songs goes up in higher temperatures.  Here’s the sound of a snowy tree cricket (Oecanthus fultoni) at different temperatures.

So here’s an interesting problem:  Female tree crickets recognize their own species by the frequency of the trill, but the frequency increases as the temperature rises.  How do they recognize the higher-pitched songs?

In a study published last April, researchers at the University of Toronto Scarborough used laser Doppler vibrometry to measure vibrations inside the crickets’ ears.  The instruments were so sensitive that they could see changes at the cellular level.

The study found that “as the temperature changes, tree cricket ears adjust at a cellular and therefore mechanical level to match the changing frequency of the song.”

Read more about it here in Science Daily.

 

(video of a tree cricket “singing” in Alameda County, California from Wikimedia Commons)

7 Oecanthus species in western Pennsylvania as shown at Oecanthinae.com:  Four-spotted (O. quadripuntatus), Snowy (O. fultoni), Black horned (O. nigricornis), Pine (O. pini), Narrow winged (O. niveus), Two spotted (Neoxabea bipunctata), Davis’ (O. exclamationis)

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Aug 06 2016

Big and Beautiful

Published by under Insects, Fish, Frogs

Royal Walnut or Regal Moth (photo by Don Weiss)

Royal Walnut or Regal Moth (photo by Don Weiss)

Beautiful moths come in all sizes.

On Monday I wrote about the pink-and-yellow rosy maple moth whose wingspan is only one to two inches.  Don Weiss supplied Monday’s photo and commented that they found this big and beautiful moth at the same time.

The royal walnut or regal moth (Citheronia regalis) is the largest moth in the western hemisphere north of Mexico.  With a wing span of 3.75 to 6+ inches, it lives in deciduous forests from New Jersey to eastern Kansas and east Texas to Florida.

Citheronia regalis is always big but not always beautiful.  As a caterpillar it’s so scary-looking that it’s called a hickory horned devil.  Click here to see its final instar on someone’s hand.

True to its name the caterpillar feeds on walnuts, hickories and a lot of other trees.  Since their only job is to procreate the adults never eat. They live only a week.

Now’s a good time to find this big and beautiful moth in southwestern Pennsylvania.

 

(photo by Don Weiss)

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Aug 01 2016

Rosy Maple Moth

Published by under Insects, Fish, Frogs

Rosy maple moth (photo by Don Weiss)

Rosy maple moth (photo by Don Weiss)

Can you believe the colors on this moth?

Fuzzy pink and yellow, the rosy maple moth (Dryocampa rubicunda) lives only a week in this beautiful body. Its wing colors are highly variable but its head and back are usually yellow with pink belly, legs and antennae.

Most of its life is spent as a green-striped caterpillar, eating maple leaves, and passing through five instars.  When fully mature the caterpillar crawls down the tree and pupates underground.

In western Pennsylvania the moths are above ground from May to September but are easiest to find in late July.  The adults don’t eat.  They have only one job, to procreate.

The action begins around sunset.  The females perch on the undersides of leaves and exude pheromones.  The males fly around “sniffing” the air with their big fluffy antennae.  Perhaps this division of labor is why the females have insignificant antennae.  (My guess is that the moth in Don Weiss’ photo is female.)

If you’re lucky to see the rosy maple moth you’ll be surprised at how small it is — only 1″ long. Click here to see one on the tip of a finger.

I found one once at the Panhandle Trail in Collier Township.  Its beauty stopped me in my tracks.

 

(photo by Don Weiss)

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Jul 27 2016

Alien On The Loose

Asian longhorned beetle animation linked from USDA website

Asian longhorned beetle animation linked from USDA website.

Eeeeewww!  It’s an alien!

I’m not kidding.  This bug is an alien invader from China that hitchhikes as larvae in wooden packing material.  When it gets here it eats trees … lots of them!  If it shows up in your neighborhood it has to be eradicated.  Otherwise your town is doomed.

The Asian longhorned beetle (Anoplophora glabripennis (Motschulsky, 1853)), or ALB, is a very large wood-eating beetle native to China and the Korean peninsula.  Its white-spotted black body is an inch long with antennae 1.5 to 2 times longer than its body.  The antennae are unique, banded black and white.

Because it arrives in infected wood, ALB’s first location in North America is a warehouse. From there it spreads unpredictably, depending on the shipment.  It’s been found in suburbs and cities in New York, New Jersey, Massachusetts, Illinois, Ohio and Ontario.  Click here for the map as of July 2015.

When the beetle gets loose it’s not picky.  Its eats maples, elms, birches, willows, poplars, ashes, hackberries, horsechestnuts, London planetrees … just about anything … but it takes 3-4 years to notice it.  The adults are active late spring until fall so July is a good time of year to see its damage or the bug itself.

And this bug is noticeable. Big and showy, even its larvae (at left) are huge.

Larva and adut Asian longhorned beetle (photos by Joe Boggs, Ohio State University, Bugwood.org)

Larva and adult Asian longhorned beetle (photos by Joe Boggs, Ohio State University, Bugwood.org)

If you don’t see the bug you may see its evidence.

This unusual leaf damage is a hallmark of ALB. They eat the ribs of leaves, not the papery part.

Leaf damage from Asian longhorned beetle (photo byPennsylvania Department of Conservation and Natural Resources - Forestry , Bugwood.org)

Leaf damage from Asian longhorned beetle (photo by PA DCNR, Forestry at Bugwood.org)

Its entrance and exit holes are unique, too.

The female excavates a niche in the bark and lays her eggs in the hole.  Each roughly chewed egg niche is half the size of a dime.

Two egg niches drilled by Asian longhorned beetles (photo by Joe Boggs, Ohio State University, Bugwood.org)

Two egg niches drilled by Asian longhorned beetles (photo by Joe Boggs, Ohio State University, Bugwood.org)

To get out of the tree, the beetle chews a perfect-circle hole as big as a pencil!

Asian longhorned beetle exit holes (photos by Leslie J. Mehrhoff, University of Connecticut and Joe Boggs, Ohio State University, Bugwood.org)

Asian longhorned beetle exit holes (photos by Leslie J. Mehrhoff, University of Connecticut and Joe Boggs, Ohio State University, Bugwood.org)

We can stop ALB if he’s confined to cities but if he gets loose in our forests all bets are off.

So if you see an Asian longhorned beetle or its damage, report it.  There are some look alikes, but USDA wants us to be better safe than sorry.  Call them at 1-866-702-9938 or click here for details.

Report this invader!  Don’t let him take hold!

Adult Asian longhorned beetle in someone's hand (photo by Michael Bohne, Bugwood.org)

Adult Asian longhorned beetle in hand (photo by Michael Bohne, Bugwood.org)

 

Read more about Asian longhorned beetles at USDA’s beetlebusters.info website.

(beetle animation linked from USDA’s website, photos from Bugwood.org)

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