Category Archives: Insects

No Snakes Day

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

17 March 2014

If you are afraid of snakes, you’ll be happy to know that March 17 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 St. Patrick 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)

Tick City!

Insects, Plants & Fungi

Japanese barberry, Moraine State Park, 20 Oct 2013 (photo by Kate St. John)

I remember these little red fruits from my childhood.  I used to pick the berries along my walk to elementary school and roll them between my fingers.  Firm, shiny, and somehow soothing.

Japanese barberry (Berberis thunbergii) is a pretty plant which forms a thorny border that discourages children and dogs from entering one’s yard.  For this and other reasons it was introduced to the U.S. in 1875.  Unfortunately by now Berberis thunbergii and its European cousin (Berberis vulgaris) have overtaken our native barberry (Berberis canadensis) and become invasive.

Japanese barberry has a secret advantage over Pennsylvania’s native plants. Deer won’t eat it so it easily forms dense, thorny thickets.  But don’t plant it!  It’s a tick magnet.

Studies by the Connecticut Agricultural Experiment Station in Lyme, Connecticut discovered a strong link between dense Japanese barberry thickets and Lyme disease.  Deer ticks prefer these thickets for their cool, moist microclimate.  White-footed mice hang out in the thickets because the larger predators can’t reach them there.  White-footed mice are the main carriers of Lyme disease bacteria.  The ticks bite the mice and voilà!  Lots of Lyme disease.

The Adirondack Daily Enterprise wrote of this study: “Deer ticks are 67 percent more likely to be in areas infested with barberry than those areas that have native plants, and a higher percentage of ticks in infested areas carry the Lyme bacteria than those in areas that are barberry-free – 126 infected ticks per acre versus 10 per acre. When managers removed barberry plants, the number of ticks dropped up to 80 percent – a compelling outcome.”

So if you want to find deer ticks and Lyme disease, bushwhack through a barberry thicket.

The plant in this photograph was alone, growing by the side of a rail trail, but I found a tick on my pants after I took the photo.

Tick City!

(photo by Kate St. John)

An Alien Takes Aim At Old Treasures

Insects, Trees

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.

Breaking And Entering

Insects

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)

On Caffeine

Insects, Musings & News
Spider webs with and without the spide on caffeine (photo from Wikipedia)

7 October 2013

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.

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

The Sun Compass

Insects, Migration
Male monarch butterfly (photo by Marcy Cunkelman)
Monarch butterfly, 2008 (photo by Marcy Cunkelman)

25 September 2013

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 credits: monarch by Marcy Cunkelman, 2008)

Green Darner Picnic

Insects
Common green darner dragonfly (photo by Tim Vechter)
Green darner dragonfly (photo by Tim Vechter)

23 September 2013

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)

Sleepy Oranges

Insects

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)

Pickerel

Insects

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)