Monday, December 22, 2014

The host with the most, part one

The bright, multicolored flowers of lantanas attract many insects to feed on the nectar they dispense.

A gulf fritillary (Agraulis vanillae) visiting lantana flowers.
However, a number of other insects specialize on extracting nutrients from lantanas in other, more destructive ways.  Recently, I observed many lantana leaves that had been hollowed out, particularly along and around the veins.

A mined lantana leaf.
Although I did not see any of the leaf miners themselves, the pattern of damage was characteristic of the herringbone leaf-mining fly.

More lantana leaves mined by the larvae of the herringbone leaf-mining fly (Ophiomyia camarae)
Meanwhile, other lantanas were suffering from an even stranger affliction -- they had thick growths of miniature stems and leaves where they should have had flowers and fruits.

Lantana flower gall mites (Aceria lantanae) made this plant produce tiny stems and leaves in place of flowers.
In this case, bud mites were the culprits.  The mites had manipulated the plants into switching from producing flowers to growing more vegetative tissue, which had developed into galls enclosing the mites.

Monday, December 15, 2014

Browner than a berry

The glossy privets in the park are now drooping with large clusters of dark berries.  Curious whether anything was feeding on the berries, I inspected several bunches.  Although I did not find any sign that the berries were being consumed, I did discover one animal that had found another use for the berries: as a shelter.

A spider wedged in amongst a bunch of glossy privet (Ligustrum lucidum) berries.

Friday, December 12, 2014

Bad hair

Out for a walk after a storm, I did not find that any more dangerous trees had fallen.  I did, however, come across a fallen tree of the regular variety and something dangerous that seemed to have fallen out of a tree.

A late instar puss caterpillar (Megalopyge opercularis), known as a flannel moth as an adult.
It was a caterpillar covered in such a dense coat of hair that it initially looked like a moving scrap of fur.

* 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

While these caterpillars look soft and furry, leading to the name "puss caterpillars", their appearance is deceptive.

The head and part of the body sometimes emerge from under the hair.
The hairs conceal numerous venomous spines capable of delivering an exceptionally painful sting.

The hair-line recedes.
Between encounters with fire ants and an upside-down jellyfish, I've had more than enough painful stings recently.  Fortunately, I was able to avoid any direct contact with the puss caterpillar.

It is more recognizable as a caterpillar from underneath.
Explore some more: Toxic "Toupee"

Monday, December 8, 2014

When a tree falls in the forest, it makes a buzz

When I found the downed tree pictured below, I was glad that I hadn't been underneath when it fell.  Then, when I inspected the tree more closely, I was glad that I hadn't been anywhere nearby when it fell.

A recently fallen tree.
The signs left inside the tree suggested that it had not come down quietly -- due to the colony of honey bees that had been living inside.

A piece of wax comb left in the hollow inside the tree.
The tree had been dead long before it had fallen, and the hollow inside it made an attractive spot for honey bees to build their hive.  If the bee colony had not already abandoned the nest cavity before the tree came crashing down, there may have been several thousand very agitated bees emerging from the wreckage of the tree.  However, by the time I came by, the cavity had been mostly cleaned out by opportunists...

One of several bug nymphs foraging in the hollow.
...with only a few bug nymphs left roaming over the bits and pieces of the bees' nest.

A close-up of another bug nymph.

Wednesday, November 26, 2014

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.

Friday, November 21, 2014

The birds in blue

While taking a walk in the small woodland near my apartment, I found that my sensitization to crow alarm calls this summer had carried over to one of their relatives: the blue jay (Cyanocitta cristata).  I followed the jeering calls of several blue jays until I located the hawk at the center of the commotion.

The hawk that had agitated the blue jays.
With the mystery of what was upsetting the blue jays solved, I decided to record the blue jay's alarm calls.  Thus, I fortuitously switched to video mode just in time to catch the startling climax of the confrontation between the blue jays and the hawk.

* 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

After successfully chasing off the hawk, the blue jays quieted down and I continued on a more peaceful walk.

Explore some more: Blue Jay (All About Birds)

Friday, November 14, 2014

Falling back, part three

The encounter that I observed between the black-and-yellow argiope and the wasp ended peacefully.  However, when I went to check on the spider a few days later, there was evidence that it had gone through a more violent confrontation in the interim.  Can you find what is missing in the picture below?

What is missing?
Either another predator targeted the spider or one of the spider's prey put up a fierce fight -- because the spider was down to seven legs.

Explore some more: Spiders Evolved Spare Legs

Monday, November 10, 2014

Falling back, part two

Although the wasp kept its distance, other insects were more willing to get close to the spider in order to get a meal.  See if you can find them in the picture below.

The black-and-yellow argiope (Argiope aurantia) spider and its prey.
If they are too small to find in the picture above, this close-up should help.

Two small flies are sitting on the spider's wrapped-up prey.
The spider is clutching a prey item already wrapped in white silk -- and if you look closely on the left and top of the white package, you can see two very small flies.  These appear to be freeloader flies (Milichiidae), which are often found in the seemingly hazardous occupation of feeding on the kills of spiders and other predators.

Friday, November 7, 2014

Falling back

Spiders can be predators of wasps, but sometimes the relationship is reversed and the spider becomes the prey.  This summer I watched a dramatic encounter that unfolded too quickly for me to capture on camera.  A spider was sitting on a leaf at the end of a tree branch while a large wasp hunted nearby.  As the wasp drew near, the spider edged away and then dropped down a thread to hang in mid-air.  For a few moments, it appeared that the spider had escaped the wasp's attention -- but then the wasp struck.  I had a brief glimpse of the wasp and spider grappling each other before they plummeted to the ground.  By the time they landed, the spider was already paralyzed or dead.

Not all spiders are so easily subdued, however.  Take, for example, the black-and-yellow argiope, one of the largest orbweaver spiders in North America (along with the giant lichen spider and the golden silk spider).

A black-and-yellow argiope (Argiope aurantia) orbweaver spider.
As I was photographing this very imposing spider, a wasp came up and hovered to inspect the spider too.

A wasp approaches the orbweaver spider.
If the disparity in size wasn't already enough to discourage the wasp from taking further action, a wave of the spider's legs seemed to complete the message.

The orbweaver spider waving its legs.
The wasp retreated, leaving the spider undisturbed.

Friday, October 31, 2014

Happy Halloween!

This fall, I found some natural Halloween decorations hanging in the park by my apartment.  There were spooky, spiky jack-o'-lanterns...

A spinybacked orbweaver (Gasteracantha cancriformis) spider.
...and spooky, spiky skulls...

Another color form of the spinybacked orbweaver.
...all appropriately surrounded by spooky spider webs!

Wednesday, October 29, 2014

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.

Wednesday, October 22, 2014

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.

Wednesday, October 15, 2014

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.

Monday, October 13, 2014

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

Friday, October 10, 2014

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"

Monday, October 6, 2014

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.

Wednesday, October 1, 2014

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.

Monday, September 29, 2014

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

Friday, September 26, 2014

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...