Archive for the 'Insects, Fish, Frogs' Category

Mar 17 2014

No Snakes Day

Published by under Insects, Fish, Frogs

Grass snake (photo from Wikimedia Commons, Creative Commons license)

If you are afraid of snakes, you’ll be happy to know that this day celebrates someone who banished them from an island.

Legend has it that St. Patrick, patron saint of Ireland, chased all the snakes into the sea after they attacked him during a 40-day fast.

In fact, there were never any snakes in Ireland since the last glacial maximum.  St. Patrick’s legend may actually refer to the rise of Christianity and the end of Druid snake symbols.

In recent years biologists in Guam are trying to accomplish St. Patrick’s legendary feat.  Invasive brown tree snakes are devastating the island’s native birds.  The snakes must go.   So far the most ingenious plan has been to air drop 2,000 mice wearing tiny parachutes.  The mice were dead bait laced with a very small dose of acetaminophen that kills the brown tree snake but nothing else.

There was no need for Tylenol to eradicate this grass snake from Ireland.  Photographed in Europe, it cannot cross the sea.

Happy St. Patrick’s Day!

 

(photo from Wikimedia Commons, Creative Commons license. Click on the image to see the original)

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Nov 10 2013

Face In A Gall

Oak apple gall that looks like a face (photo by Kate St. John)

Before the oaks leafed out last spring I found this oak apple gall on a seedling at Cedar Creek Park.

When I bent down to look closely I saw the face.

Now that the leaves have fallen, look for fun features like this on the bare trees.

 

(photo by Kate St. John)

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Oct 25 2013

An Alien Takes Aim At Old Treasures

Hemlock woolly adelgid at Jacobsburg (photo by Nicholas A, Tonelli via Wikimedia Commons)

Last spring the hemlock woolly adelgid (HWA) reached Cooks Forest, scary news for the old-growth eastern hemlocks there.

The pest is easy to recognize by its white egg sacs that cling to the underside of the branches.  They kill hemlocks by sucking the juice out of the needles.  Infected trees look gray-green instead of deep green and, under a heavy infestation like the one shown above, can die in only four years.  This is sad anywhere but especially unfortunate in Cooks Forest where the old growth hemlocks are over 300 years old.

It has taken a long time for the bug to reach Cooks Forest.  HWA arrived from Asia in 1924 but moved very slowly across the eastern U.S.  By 2007 it was present in 50% of the eastern hemlock’s range, unable to spread far northward because of harsh winters. Unfortunately our climate is warming so new adelgid territory opens up every year. (Notice on this NOAA plant hardiness map that the location of Cooks Forest warmed enough to change growing zones.)

HWA was first spotted in eastern Pennsylvania in 1967 but took about four decades to cross the Allegheny Front into western PA.  Slowly, slowly it crept toward Cooks Forest.  By 2010 it was in the vicinity.  This year it was there.

Knowing the imminent danger DCNR has treated the area and the old growth trees.  They use biological controls — Asian beetles that eat adelgids, though not enough of them — and soil or bole-injected insecticides on specific trees.  The poisons are systemic, similar in concept to the insecticide treatments for emerald ash borer that kill or repel all insects.  The treated trees will have fewer insects living on them.  Will this make them less useful to birds?

The question hardly matters.  Nature can’t produce a 300 year old hemlock as fast as the adelgids can destroy one.   In the case of our oldest treasures our task is clear.  Save these trees if we can.

For more information on the hemlock woolly adelgid, click here for DCNR’s report.

 

(photo via Wikimedia Commons by Nicholas A. Tonelli at Jacobsburg, Northampton County, PA. Click on the image to see the original)

 

p.s. Thanks to Kim Getz for alerting me to this news.  Because of the adelgids activity cycle, DCNR treated the old-growth trees in May and again in October.

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Oct 15 2013

Breaking And Entering

Published by under Insects, Fish, Frogs

Stinkbug on the falconcam (National Aviary falconcam at the University of Pittsburgh)

Look closely at the big dark blob near the top of this picture.

Ewwww.  It’s a brown marmorated stinkbug!

So many stinkbugs were searching for cracks to crawl into last weekend that one tried the falconcam and triggered this motion detection snapshot.

How many security cameras have taken stinkbug photos this month?

How many stinkbugs have broken in?

 

(snapshot from the National Aviary falconcam at the University of Pittsburgh)

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Oct 07 2013

On Caffeine

Spider webs with and without the spide on caffeine (photo from Wikipedia)

This blog is made possible by caffeine…  administered every morning in a 16 oz mug of coffee at 5:00am.  Boing!  I’m awake!   It works.  And it makes me happy.

Apparently it is not good for everyone.

According to Wikipedia, Swiss pharmacologist Peter Witt began testing different drugs on European garden spiders in 1948 because a zoologist friend of his, H. M. Peters, was annoyed that the spiders always wove their webs between 2:00am and 5:00am.  Dr. Peters wanted to study web building when he was awake, not when the spiders were.

Naturally it made sense to try caffeine.  Perhaps it would keep the spiders awake longer so that they’d “sleep in” and start weaving after dawn.

Not so!  Instead of time-shifting their web construction, caffeine made the spiders build whacky dysfunctional webs.

In 1995 NASA conducted a similar study and took photographs of the spider webs both before and after caffeine (above).

So much for Dr. Peters’ brilliant idea.  He was forced to study his subjects in the dark.  I’m sure he had to be on caffeine to do it.

Happy Monday.

(photos from Wikipedia. Click on the image to see the original)

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Sep 25 2013

The Sun Compass

Male monarch butterfly (photo by Marcy Cunkelman)

A week ago I saw my first and only monarch butterfly of 2013.  Their sudden disappearance is both troubling and saddening.  It’s now possible to imagine a world without monarch butterflies.  We are nearly there.

Last winter’s monarch survey in Mexico showed their population was down 59%, a record low.  There have always been population fluctuations but the trend has been running low and lower since 2004.  Scientists believe that agricultural pesticides and herbicides have reduced available poison-free habitat for butterflies (similar to the bees’ problem), so this spring monarch enthusiasts encouraged people to grow safe-haven milkweed for the butterflies.  It wasn’t enough.

Each species has an intrinsic value.  If, or when, the eastern monarch butterfly goes extinct we will lose its pollination contribution, milkweed symbiosis, beauty, and the amazing adaptations that allow multiple generations to migrate from Mexico to Canada and back.

One of the adaptations that will disappear is this:  Monarch butterflies have a sun compass in their antennae.

Their antennae have light sensors that track the amount of light each day.  According to a study in 2009 by Merlin, Gegear and Reppert, this circadian clock “provides the internal timing device that allows the butterflies to correct their flight orientation, relative to skylight parameters, and maintain a southerly flight bearing, as the sun moves across the sky during the day.”  Migratory monarchs without antennae fly in aimless directions.  Monarchs with antennae always orient southwest.

The monarch’s sun compass was discovered only a few years ago.  Now there are almost no monarch butterflies to study.  The world will be a poorer place without them.

Click here for more information on the monarch’s amazing sun compass.

(photo by Marcy Cunkelman, 2008)

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Sep 23 2013

Green Darner Picnic

Published by under Insects, Fish, Frogs

Common green darner dragonfly (photo by Tim Vechter)

The weather was sunny and cold a week ago when I visited Flagstaff Hill so I was surprised to see over a hundred Green Darner dragonflies patrolling in the chilly breeze.  They were having a picnic.

Each dragonfly faced the wind and hovered, then wheeled away to a new spot and hovered again.  With binoculars I could see thousands of small insects being blown uphill in the wind.  The dragonflies reached out and grabbed them. Their wings glinted orange in the sun.

Green darners migrate south in the fall so I was witnessing a “flock” that happened to stop there for an easy meal.

I don’t have a video of their amazing maneuvers but this one shows how they do it.

 

(photo by Tim Vechter)

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Sep 22 2013

Sleepy Oranges

Published by under Insects, Fish, Frogs

Male Sleepy Orange butterflies in New Mexico (photo by Steve Valasek)

I was captivated by this photo Steve Valasek took in New Mexico.  What butterflies are these?

Chuck Tague filled me in:

These are Sleepy Orange butterflies, Eurema nicippe (or Abaeis nicippe), a common sulphur butterfly in the southern U.S.  They range as far north as western Pennsylvania and occur regularly in a field near Mark and Loree’s place in Rostraver.   Some years they irrupt northward in good numbers.

The two in this photo are males.  They need minerals to reproduce which they’re extracting from wet mud or sand (called puddling).

Sleepy Oranges are common now in Florida.  I’ve raised several this year and collected an egg about a month ago that should emerge from its chrysalis this week.  Here’s a photo of one that just eclosed:

Sleepy Orange butterfly eclosing (photo by Chuck Tague)

 

Google “Eurema nicippe” and you’ll see that the ventral side of the butterfly (underwing, wings closed) is not as interesting as the dorsal side (top, wings open).  Click here to see a Sleepy Orange with its wings open.

 

And why “sleepy”?  There are two theories:  It flies slowly for a sulphur (this notion is disputed) –or– The two spots on its dorsal wings look like sleepy eyes.

 

(photo of two butterflies on mud by Steve Valasek, photo of eclosing Sleepy Orange by Chuck Tague)

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Sep 18 2013

Pickerel

Published by under Insects, Fish, Frogs

Pickerel frog (photo from Wikimedia Commons)

I can tell the habitat is clean in Maine (no acid mine drainage!) because I saw a lot of frogs while hiking there on vacation.

Here’s one that surprised me by the intricate pattern on his brown back. (not my own photo)

Unlike northern leopard frogs which have circular spots on a green background, pickerel frogs have blob-like rectangles.

It’s useful to know the difference because frightened pickerel frogs excrete a substance from their skin that’s toxic to other frogs and mildly irritating to human skin.  Snakes won’t eat them.

No frogs’ legs on the menu with these!

 

(photo from Wikimedia Commons. Click on the image to see the original)

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Sep 06 2013

Even One Species Makes a Difference

Bumblebee (photo by Marcy Cunkelman)

In yesterday’s blog I mentioned the pesticide episode in Wilsonville, Oregon last June that killed 50,000 bumblebees.  This prompted me to wonder…

What would happen if just one species of wild bee completely disappeared from an area?

Computer models suggest that the remaining bees would take up the slack and none of the flowers would suffer.  Recent research shows this isn’t so.

Berry Brosi of Emory University and Heather Briggs of University of California Santa Cruz conducted a bumblebee study at the Rocky Mountain Biological Lab near Crested Butte, Colorado where native larkspur is visited by 10 of the 11 local bumblebee species.

They divided the wildflower meadows into 20 square meter plots.  In the manipulated plots, they used nets to capture and exclude just one bumblebee species.  In both the control and manipulated plots their team of Emory University undergraduates followed all the bumblebees everywhere, noting the flowers they visited.

Though bees are generalists they usually specialize in gathering nectar from particular species at the height of their blooming.  If you watch bumblebees on Joe Pyeweed in an August meadow you’ll notice they visit all the Joe Pyeweed in succession even though there are lots of other flowers to choose from. This benefits the flowers because the bees are wearing pollen from their own species.  The researchers confirmed this when they swabbed the bumblebees for pollen and analyzed the results.

In the control plots in Colorado, everything proceeded as expected.  78% of the bees focused on their favorite flower species. Larkspur seed production was normal.

Not so in the manipulated plots. With only one species missing, reduced competition for the flowers prompted the bumblebees to “play the field.”  Only 66% of the bumblebees focused on their favorite flowers.  The larkspur suffered, producing 1/3 less seed.

So the answer is:  If one wild bee species disappears some wildflowers will decline dramatically.

Everything’s connected to everything else.

Read more about the bumblebee study here in Science Daily.

 

(photo by Marcy Cunkelman)

p.s. No bumblebees were hurt during the study.  They were all captured and released.  Quite a feat!

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