A caterpillar green around the gills, part three

The wasp pupae did not look particularly remarkable, but inside a rapid transformation was taking place. In just one week, the wasps emerged as adults.

The newly emerged wasps gathering on the lid of the vial.

They were, of course, still just as small. Nevertheless, looking closely, it is possible to see that there were two types of wasps. While some of the wasps had typical antennae, the antennae of the other wasps were branched, giving the appearance of delicate antlers.

A view of the wasps from underneath.

The two types of wasps did not mean that the caterpillar host had been parasitized by two different species, however. The two types were males and females. As in some other insects (for example this moth and this mosquito), the more elaborate antennae belonged to the males.

The wasps likely belong to the tribe Eulophini in the family Eulophidae.

Finally, it was time for the wasps to go off in search of their next hosts -- though the one pictured above spent some time inspecting my hand before disappearing into the air.

A caterpillar green around the gills, part two

After emerging from their caterpillar host, the young wasps quickly lost their plump, bright green forms.

Day 1: The wasp larvae (right) emerge from the moth caterpillar (left).

Over the next two days, they first faded to a dull yellow...

Day 2: The wasp larvae begin to pupate.

...and then shriveled and blackened.

Day 3: The wasp larvae have become pupae.

However, the wasps were not sickening and dying -- they were progressing normally through their development from larvae to pupae. Meanwhile, the moth caterpillar that stood by, apparently healthy except for its inertia, had its own development frozen. To be continued...

A caterpillar green around the gills, part one

This Halloween, instead of featuring a seasonable insect or spider, I will share a spooky story of a "possessed" caterpillar.

Parasitoids may be among the smaller enemies that a caterpillar has, but they are also among the most insidious.  When a female parasitoid (generally a small wasp or fly) finds a suitable caterpillar, it lays its eggs on or even inside the caterpillar.  The parasitoid larvae then emerge from the eggs and proceed to feed on the caterpillar.  What becomes of the caterpillar once the parasitoid invasion is complete?  It may be mummified, vanish from inside a fuzzy shroud, or perhaps more strangely -- be left apparently unharmed.

A copper underwing (Amphipyra pyramidoides) caterpillar and recently emerged parasitoid wasp larvae.

The light green caterpillar shown above and below is surrounded by the darker green larvae of a parasitoid wasp.  The wasp larvae had recently finished feeding inside the caterpillar and had broken through the sides of the caterpillar to finish their development outside.

The slits that the wasp larvae emerged through are visible behind them.

Meanwhile, the caterpillar just sat there as if unperturbed by the litter of parasitoids.

However, the caterpillar was hardly passive.  When the parasitoid larvae were threatened by an approaching object, the caterpillar became surprisingly aggressive.

The parasitoids had left the caterpillar alive, but not at liberty.  Though the caterpillar was no longer needed as food, it could still be manipulated into serving as the parasitoids' protector.

To be continued... but in the meantime, you can explore some more: Parasitoid Increases Survival of Its Pupae by Inducing Hosts to Fight Predators

A tough egg to crack

Last summer, I kept seeing song sparrows and gray catbirds coming in and out of a dense patch of rosebushes.

A song sparrow (Melospiza melodia) emerging from the rose bushes.

I guessed that they had built nests somewhere deep inside.  Although I eventually found the song sparrow nest, I was disappointed that I could not locate the catbird nest.  So, as a surprise, my mother put a wooden egg in an old nest and left it for me to stumble upon.

A large, blue egg in a nest.  (Not a real egg.)

 However, something else found the egg first.

When I heard crows squabbling, I looked out and saw that one of the crows was sitting on the ground by the rosebushes and attempting to eat what appeared to be a gray catbird egg.  Of course, not knowing that a wooden egg had been placed outside just minutes before, I assumed that the crow had found and raided the catbird nest.  The truth only emerged when I shared the sad news about the catbird nest with my mother.  She quickly led me to the nest where the wooden egg had been. As she had suspected, the nest was empty.  When the wooden egg finally reappeared in the yard several days later, it was in splinters.  (The photograph of the egg in the nest above showed a reenactment using a spare egg.  We immediately brought that second egg back inside!)

The caterpillars eat their match, part three

Compared to the orange-barred sulphur butterflies, adult geometrid moths do not appear very active (at least not during the day)...

A pale beauty moth (Campaea perlata).

...and most of them are not very bright or flashy.

A large lace-border moth (Scopula limboundata).

However, geometrid caterpillars can be just as impressive as orange-barred sulfur caterpillars when it comes to blending in with the flowers that they eat.

A purple geometrid caterpillar on purple flowers.

In addition, at least some geometrid caterpillars have the same ability to change their color in order to match their background.  

A pink geometrid caterpillar on a pink rose blossom.

Although many geometrid species feed on other parts of plants (and mimic those instead), there are well over a thousand species of geometrid moths in North America -- including plenty of ones with colorful, flower-eating caterpillars.  See a few more of them here: Geometrid larvae on flowers

Heart of the stone

Lichens are a classic example of symbiosis -- the close association of two or more species.   In fact, the word "symbiosis" (literally, "together living") was coined in order to describe lichens.  The structure of a lichen is formed by a fungus.  Meanwhile, cells of algae and/or cyanobacteria are embedded within the fungus and perform photosynthesis to capture energy.  Although symbioses are not always harmonious relationships, the lichens pictured below appear to be the symbol of affection.

Lichens on a rock.

Explore some more: The lichen symbiosis - what is so spectacular about it?

Too much ground to hog

I can't think about Groundhog Day without recalling our backyard groundhogs, and today I have been imagining them snug in their burrows deep under the snow.

A surprise encounter with a groundhog when I went to photograph its burrow entrance.

Last summer we had two frequent groundhog visitors -- or rather, at least two, since I'm not very confident in my ability to distinguish between individual groundhogs.  However, I was sure it had to be at least two.  Though we only ever saw one groundhog at a time, the conspicuous difference and rapid alternation between big...

The big groundhog.

 ...and small groundhogs was enough to convince me that there was more than one.

The little groundhog.

I was especially worried that the small groundhog would make a tempting target for the red foxes, but it grew steadily larger over the course of the summer, while the squirrel population steadily declined.

Here is a video of the smaller and larger groundhogs for comparison:

Remembering old acquaintances

To start off 2015, here is a look back at one of the highlights of 2014 -- the red foxes.  Most of the time, I encountered the foxes in the road or in the yard.  However, a couple of times, I found them down on the rocky beach (where they had been harassing the shorebirds).

Two red foxes (Vulpes vulpes) on the beach.

On this particular occasion, three of the foxes playfully roamed over the rocks.  I hope you enjoy watching the foxes and have a happy new year!

* To see this video in high definition (1080p), you may need to: 

(1) click "YouTube" to watch on the YouTube website

(2) change the settings at the bottom of the video screen

Happy Thanksgiving!

To celebrate the holiday, I'm sharing this nice turkey I caught (just on camera, of course).

A wild turkey, making a hasty retreat.

Adding eggs to the basket

Around the time that the tortoise beetles were leaving their eggs on the bindweed, I found two small cabbage white butterflies laying lots of their own eggs in the garden.  Small cabbage whites are native to Europe, Asia, and north Africa -- and so too are the garlic mustard plants that they chose as hosts for their offspring.

A female small cabbage white butterfly (Pieris rapae) on a garlic mustard (Alliaria petiolata) leaf.

The butterflies fluttered from leaf to leaf, sometimes moving on quickly and sometimes pausing to lay a single egg before going off in search of the next suitable leaf.

A small cabbage white butterfly (Pieris rapae) egg.

The butterflies appeared to be spreading their eggs out amongst the available leaves, which made sense to me as a way of reducing the risks of predation, parasitism, and competition.  Therefore, I was surprised by what I found when I went to check on the eggs again later.

Now there are two small cabbage white butterfly eggs!

Where there had been just one egg, there were two eggs.  Even more surprisingly, where there had been two eggs...

Two small cabbage white butterfly eggs underneath a garlic mustard leaf.

...there were seven eggs!

Now there are seven small cabbage white butterfly eggs under the leaf.

The ugly larvae, part two

As larvae, tortoise beetles are made distinctly unattractive by the amalgamation of frass and shed skins that they hide beneath.

A green tortoise beetle larva with its fecal shield.

Yet, the beetles undergo a remarkable change when they metamorphose into adults.

A golden tortoise beetle (Charidotella sexpunctata).

Even having seen pictures of the adults beforehand, I was stunned when I saw the shining beetles in the backyard one evening.

A golden tortoise beetle (Charidotella sexpunctata) showing some orange coloration.

That evening, there were many tortoise beetles on the bindweed around the garden and they were from at least two different species.

A mottled tortoise beetle (Deloyala guttata).

However, by the next day, all the adults were gone.  I thought that they might just have gone into hiding for the daytime, but they had not returned to the bindweed by the time I checked again in the evening -- or any time later.  They had left something of themselves behind, though!

Tortoise beetle eggs attached to the underside of a bindweed leaf.

A few days later, the larvae began appearing and were soon devouring all the bindweed.

The ugly larvae, part one

Like spittlebugs, tortoise beetle larvae conceal themselves underneath an excretion of the plant material that they eat.  However, since the beetle larvae feed on leaves rather than sap, the end product is not nearly as elegant as the spittlebugs'...

A tortoise beetle larva with its fecal shield raised.

...nor is the process of making their coverings.

A tortoise beetle adding to its shield.

Yet regardless of aesthetic objections, the fecal shields seemed to be quite adequate for the purpose of protecting the larvae, which thoroughly infested the bindweed in the garden without attracting any predators or parasites (as far as I could see).

Three tortoise beetle larvae on a mostly eaten bindweed (Convolvulaceae) leaf.

Growing up in bubbles, part two

After feeding on lots of plant sap from within its blanket of bubbles, the spittlebug nymph sheds its skin...

The exuviae of a spittlebug nymph.

...and emerges as an adult froghopper.

An adult froghopper (Aphrophora sp.).

In addition to discarding its old exoskeleton, the adult froghopper abandons the bubbly shelter that kept it safe as a nymph.  It no longer needs to hide from its enemies, since it can easily escape them.  True to their name, froghoppers are very adept at hopping.  In fact, they are among the best hoppers in the world (especially when accounting for their size).

Explore some more: Guinness world record: highest jump by an insect and Jumping performance of froghopper insects

Growing up in bubbles, part one

Caterpillars are not the only animals that are resourceful in using their food plants to hide themselves from danger.  While hiding inside the plants' leaves and stems is relatively common, one group literally forms protective bubbles by blowing air into an excretion of the plants' sap.

Bubbles on a goldenrod (Solidago sp.) stem.

The result is a blob of bubbles, commonly referred to as frog spit, snake spit, or cuckoo spit.  However, the "spit" does not come from any frog, snake, or cuckoo; it comes from a small insect concealed underneath the bubbles.

Something is visible underneath the bubbles.

When the bubbles are brushed away, the bubble-blower -- a spittlebug -- is revealed.

A spittlebug (a.k.a. froghopper) nymph.

Although the bubbles were easy enough for me move aside, they apparently form an effective barrier against smaller enemies, as well as the elements.

Explore some more: "The frothblower"

A stitch too late

The hydrangea leaftiers wrapped themselves in multiple layers of protection, but what did they need to be shielded against?  Another group of caterpillars that I encountered over the summer illustrated a potential danger.  These caterpillars were also busy tying leaves.

Woven together leaves.

However, as they built their shelters, they were exposed on the exterior of the leaves.

A caterpillar, probably of a tortricid moth (Tortricidae). 

One of the vulnerable caterpillars exhibited evidence of a recent attack: two parasitoid eggs attached to its body.

A caterpillar with two parasitoid eggs on it.

Even if this caterpillar escaped the attention of predators and hid itself within the leaves, it was probably the parasitoid larvae that benefited from the shelter in the end.

All sewn up, part three

After sealing itself up inside the hydrangea leaves, what did the hydrangea leaftier caterpillar do?  From the outside, there was no obvious sign that the caterpillar was feeding on the leaves.

Hydrangea leaves after an encounter with a hydrangea leaftier (Olethreutes ferriferana) caterpillar.

Pulling apart one of the older leaf capsules to see what was happening inside, I found something that did not look very much like a caterpillar.

Nested inside the sealed leaves was a sealed bundle.

It looked a lot like a clump of moldy frass, but I tried separating it anyway -- and out popped a twitching pupa.

Inside the cocoon was a hydrangea leaftier (Olethreutes ferriferana) pupa.

By tying the hydrangea leaves together and then forming a cocoon inside, the caterpillar had made a snug refuge with multiple layers of security to protect it during its metamorphosis into a moth.

All sewn up, part two

A few days after first observing the strange affliction of the hydrangea leaves, I managed to find a set of leaves that were only partially sealed.

Hydrangea leaves partially woven together.

Lines of silk laced back and forth between the leaf margins, leading up to the weaver itself: the aptly named hydrangea leaftier.

A hydrangea leaftier (Olethreutes ferriferana) moth larva.

Weaving the hydrangea leaves together is a big -- and very slow -- job for such a small caterpillar.  Here is a brief clip showing the weaving process up close and then zoomed out to show the extent of the task...

* To see this video in high definition (1080p), you may need to: 

(1) click "YouTube" to watch on the YouTube website

(2) change the settings at the bottom of the video screen

...and here is a longer clip, played at 32x actual speed, to illustrate how the leaves are pulled together by the caterpillar.

* To see this video in high definition (1080p), you may need to: 

(1) click "YouTube" to watch on the YouTube website

(2) change the settings at the bottom of the video screen

All sewn up, part one

While checking for insects on the plants around the garden, I noticed that many of the new hydrangea leaves seemed glued together.

Hydrangea leaves tightly stuck together.

Several of the leaves were even deformed from continuing to grow without the room to expand.

More hydrangea leaves stuck together.

Something had tied the leaves together and was hiding inside, but what?  Unlike rolled leaves, there was no opening left between the hydrangea leaves for the occupant to exit through -- or for me to peer through.  To be continued...

Flying into the fangs of danger

Damselflies are nimble predators of other insects, but even predators can become the hunted if they are not careful.  The damselfly pictured below appears to be suspended in flight...

A slender spreadwing damselfly (Lestes rectangularis) hanging in mid-air?

...because it is suspended -- from the spider web it had just flown into.  As usually happens when something becomes tangled in a spider's web, the spider quickly approached to secure its prey.

A spider approaches the damselfly caught in its web.

The damselfly was not about to be taken without a struggle, however.

The damselfly attempts to evade the spider.

By beating its large wings, the damselfly was able to force itself free from the web just in time.  A similar encounter must have occurred between the dragonfly and spider pictured below, but with a very different ending.  Apparently, having strong wings is not always enough to escape becoming a meal for a spider.

A giant lichen spider (Araneus bicentenarius) with a dragonfly in its web.