Wednesday, November 28, 2012

Pop Went The Pupa

    Perhaps, I should have called this post, "Pop Went The Pupal Skin" since what popped the "head" off of this pupal skin wasn't the original occupant. moth pupal skin with escape hole from parasitic wasp    We found this small moth pupa under a piece of bark on a dead hickory tree that had I cut down (this kind of thing happens when a naturalist cuts firewood ).  We put the pupa in a cup and basically forgot about it.  Last night I heard some small popping noises among the collection of nature items on my desk.  I found the noise was emanating from a cup that contained the pupal case of a butterfly and a moth.  I set the cup in front of me for observation.  The noise continued intermittently for a few minutes.  Then it quit. When I glanced up, I saw this freshly emerged ichneumon wasp.
parasitic wasp emerged from moth pupa
 This small, black-and-white ichneumon wasp is about a half an inch long without measuring the antennae.
parasitic wasp hatched from moth pupa
 The larvae of this ichneumon wasp probably grew from an egg deposited in the host caterpillar.  After the caterpillar pupated, the wasp larvae killed its host and continued to feed and grow inside its host's pupal case.  After we brought the pupa into the house, the wasp probably pupated within the pupal case and I spotted it soon after it popped the hatch.
Notice the dark frass pile in the tail-end of the pupal case.
pupal skin with escape hatch of parasitic wasp
I took these photos toward a light to show the empty pupal skin (except for the frass), and also accent the wasp's escape hatch.  I wish I would have thought of holding the pupa up to the light a few days ago... I could have previewed what was going to emerge.
black-and-white ichneunon wasp
There is an incredible amount of parasitism happening in the pupae of insects.  I should not have been surprised to have this sharp-looking, parasitic wasp pop out of a pupa.

Monday, November 26, 2012

Eggs On A Hairy Cocoon

This hairy cocoon is covered with a foamy egg-mass.
eggs on coccon
   While it may seem unusual to see eggs deposited on top of a cocoon, this is how some tussock moths lay their eggs.  Here is another one of those egg-covered cocoons that I found on the bark of an oak tree along the trail, not far from the cocoon pictured above.
egg mass on cocoon
The froth covered eggs are deposited on the silk strands and multicolored caterpillar hairs of the cocoon.  There is even some hair (possibly moth hair) incorporated into the froth.
frothy egg mass of tussock moth
  Hidden under the layer of silk and caterpillar hair, there is an empty pupal case.
empty pupal case of tussock moth
  What is going on here?  How did this interesting combination of an empty pupal case, hair, and frothy eggs come about?
  Well, when White-marked Tussock Moth caterpillars (Orgyia leucostigma) pupate, they incorporates their hairs into a protective covering over themselves.
White-marked Tussock Moth caterpillar (Orgyia leucostigma)
   After pupation the moths emerge.  The males fly off and follow chemical signals to find the females.  The female tussock moths are flightless moths.  They lay their eggs on, or near, their cocoon.
The eggs (at least those of the White-marked Tussock Moth and some other tussock moths) are laid in a froth, or foam, which hardens and holds the eggs in a mass. 
When the caterpillars hatch, they "balloon" to new locations... and the process begins anew.
froth covered eggs of tussock moth
 Perhaps next spring....

Saturday, November 24, 2012

A Moth With No Wings

  There she was in the schoolyard, on the trunk of a maple tree...  a flightless moth.... a wingless moth...
a moth with no wings - a female Fall Cankerworm Moth
   I think this was a female Fall Cankerworm Moth.  She was very small... about 3/8ths of an inch long.
   It's somewhat of an oxymoron to think of a wingless moth.  However, there are quite a few species of moths that have flightless females.
a flightless moth
  About all these flightless moths can do is run around on the trees and emit pheromones to attract the males (the males can fly).  This strategy works, but it seems to me its a rather sad loss of genetic information... what if it were a butterfly without wings?
a wingless moth
   When I found this odd-looking moth, we were at a schoolhouse for family get-together.  I went around the schoolyard looking for anything interesting.  I showed this wingless moth to a number of people of various of age groups.  They all seemed intrigued by its lack of wings.
   A moth that has no wings!  I'd say that qualifies it as an interesting moth.

Wednesday, November 21, 2012

I'm Thankful For...

Well... many things!
Of the manifold works of God abundantly displayed here in mountainous Pennsylvania...

... I'm even thankful for winter crane flies dancing in shafts of sunlight in the forest.
winter crane flies dancing in a shaft of sunlight
This evening I watched the flashes from the sunlit wings of winter crane flies as they swarmed in the beams of sunlight that filtered through the trees.
winter crane flies dancing in a beam of sunlight
 I didn't get a close-up photo of the dancing flies, but they probably looked similar to this...
  Here is a photo looking directly up into a swarm of winter crane flies.
swarm of winter crane flies
Here is a series of photos of an admittedly small swarm of winter crane flies dancing in the sunlight....

... between the laurel bush in the foreground, and a white pine branch and white oak trunk in the background.  Enjoy!

sunlit swarm of winter crane flies

winter crane flies dancing in the sunlight

The Old Book says,
 "Truly the light is sweet, and a pleasant thing it is for the eyes to behold the sun." Ec.11:7

Happy Thanksgiving!

Tuesday, November 20, 2012

Stirring Up A Winter-flying Moth - A Surprise Sallow

We met this furry creature on the mountain top on Saturday.
 We think it could look like a rabbit with all its furriness and its big eyes. However, this is the face of a winter-flying moth.
   I think this is a Morrison's Sallow (Eupsilia morrisoni).  All that hair (its thoracic pile) helps retain the moth's body heat during flight. That insulating pile helps these Noctuid moths (owlet moths of the subfamily Cuculiinae) with their amazing ability to fly on mild winter days.
   What caught my attention with this particular moth, was seeing a moth flying so late in the fall when few other insects are flying.  I watched the moth fly through the woods and land about 15 ft. up in a tree.  Soon it flew down to the ground and landed on a lichen-encrusted rock, where I took the close-up photos above.
On this mid-November day, my boys and their cousins were messing about in the woods.  As I approached the boys to see what they were doing, I saw they were building some forts.
 They were disturbing the area slightly. In their messing about, they were stirring up the leaf litter. This disturbance brought the moth out of its hiding spot in the leaf litter just at the moment I was close enough to see it fly.
 I saw the moth fly up from the ground and head for the tree tops.
   Winter-flying moths like this sallow spend the winter hidden in the leaf litter.  They overwinter on the ground where the temperature hovers near freezing.  On mild winter days these moths can shiver to raise their body temperature in order to fly around to feed on sap leaking from tree wounds.  I've seen some  winter moths visiting a maple sap bucket.

I have previously posted about seeing flying moths in late November.

Read more about winter-flying moths and other amazing  thermoregulation feats in Bernd Heinrich's book...

Friday, November 16, 2012

Much More Than A Fallen Leaf

I spotted a fallen leaf... a leaf that is much more than just a fallen aspen leaf.
That made my day!  Can you see why?
aspen leaf with gall of Poplar Petiole Gall Moth (Ectoedemia populella)
Did you notice the tiny ball gall on the stem?  I stood at one spot and picked up over a dozen leaves with galled stems.  I was surprised at how many aspen leaves with galls were scattered under this aspen grove.   
Aspen grove
   These cute little caterpillar galls are caused by the larvae of the Poplar Petiole Gall Moth (Ectoedemia populella).  The galls were home (and food supply) for the caterpillars as they grew during the summer, but now the galls are empty.  I found exit holes where the caterpillars left their galls to pupate in the ground.
  This photo shows a galled aspen leaf lying on the carpet of leaves underneath the aspen stand.
aspen leaf stem gall
  What is so special about aspen leaves with swellings on the stems?  See my previous post that goes into much more detail about the aspen galls.

Tuesday, November 13, 2012

The Alder Bush: Uncovering what is boring about it

Could an alder bush be more than an ordinary bush? 
Speckled Alder by the water
 Could a series of Nature Posts enliven a seemingly boring alder bush?
   Speaking of boring, there are some intriguing insect larvae boring round-n-round in galls on the alder's branches. These larvae cause lumpy galls to form on the alders. I see several galls on the alder bush pictured above.
    I peeled the bark off an alder gall as if I was peeling the skin off of a potato.  This revealed the frass-filled galleries of a wood-boring larva that had caused the gall.
tunnels of a wood-boring larva in an alder gall
  Pretty, isn't it?
  This next photo shows an alder gall - an irregular swelling on the upper branches of the alder bush.  This is an alder stem gall caused by the larva of an Alder Gall Buprestid - Eupristocerus cogitans.
Alder stem gall caused by the larva of the Alder Gall Buprestid - Eupristocerus cogitans

Alder Gall Buprestid larvae are flat-headed borers.  That name comes from the broad thorax.
larva of the Alder Gall Buprestid - Eupristocerus cogitans
I found this larva in the partially exposed tunnel on the upper right of the gall in the photo below.   Tunneling is also evident on the lower left of the split-open area.
tunnels in an alder gallHere is a photo of another gall that I split open.
frass in wood-boring larva galleries
I made Alder flitches to display buprestid larvae tunnels.
  The general trend of the tunneling seems to be around the stem.  I've peeled some bark off alder galls and found sinuou, but parallel, tunnels going entirely around the alder branch (see photo below).  I'm somewhat surprised this tunneling doesn't effectively girdle and kill the branch... perhaps it happens slow enough for the alder to heal... perhaps the boring happens beneath the critical sap-carrying structures.
feeding galleries of the alder gall buprestid
 Here is another photo of an alder gall with the bark removed in order to show the Alder Gall Busprestid's  feeding tunnels.
frass-filled galleries in an alder stem gall
I wanted to place this peeled gall beside an undisturbed one to illustrate that there are some extraordinary things happening in an alder bush.
Alder stem gall caused by the larva of the Alder Gall Buprestid - Eupristocerus cogitans
  The alder bush is a "lively" place... can you imagine?
We've "scratched the surface" with alder galls, don't you think?
Alder beside the lake
Since we've uncovered what is boring about... inside the alder stems, there are a few more items of interest on the alder bush by the water's edge.  We'll visit the alder again.
See part one in this series on interesting facts about alder

Saturday, November 10, 2012

An alder bush at the water's edge

When I walked down to the water's edge, I didn't see any loons... or Bald Eagles...just trees and lake... Oh, and I saw this lone alder bush.
Alder bush by the lake
   Of course, alder bushes are more that just bushes to me.  Like everything else in the natural world, there's much more to alder bushes than meets the eye.  To illustrate what I mean, why don't I zoom in on the alder bush and examine a few things within the frame.
Alder stem galls
   I focused the camera on some alder stem galls.  Somewhat blurred in the photo are some catkins that will hang all winter waiting for spring.  In the background are some "alder cones" at work dispersing this past summer's crop of seeds.  In the foreground are some leaves showing some evidence of herbivore activity.
  There's more there, but that should keep me busy for a while.  I'll just have to remember to turn my camera onto these common bushes.  I have many memories of alder bushes, alder thickets, and the great stuff in them, but not many detailed photos.
  The amazing alder bush is mixed in amongst the subjects of a number of our photos.  For example: I think that's an alder bush with a dark background in the picture below.
Here's another alder beside a lake with loons.
Here's a photo of an alder thicket.
By the way, how do you take an attractive photo of an alder thicket?  Perhaps like this?
Alder thicket in a swamp
Those examples of alder bushes will suffice for now.
   Alder is such a part of our lives it shows up in many memories and photos, but its easy to skip taking pictures of the interesting details.  As soon as I have some more photos I'll post about the alder stem galls, the catkins, etc.