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!)

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.

This one is a cliffhanger, part three

Once I focused on the fact that there were multiple swallow species present, the wide variation in the placement, structure, and stage of the nests began to make sense.

The cliff swallow nests looked the most precarious; they opened outwards and hung where the bridge beams met the supporting columns (see here and here).  These nests were also the furthest behind in development -- while the cliff swallows were still extending their nests and incubating their eggs, the other swallows were busy feeding their chicks.

The cave swallows had built their deep nests in the corners formed by perpendicular beams.  Although I could not see into the nests, the steady stream of feeding visits by the parents was a good indication that there were growing chicks hidden inside.

* 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

Meanwhile, the barn swallow chicks were quickly outgrowing their nests, which were shallow cups balanced on narrow ledges.

Four out of five barn swallow chicks agree: it is time for food!

These chicks eagerly watched each adult swallow that came nearby and opened their beaks wide for food, regardless of whether the adult was one of their parents or not.  Since there were many nests under the bridge, the chicks' gaping, yellow mouths were ignored more often than not.

* 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

Nevertheless, the chicks had soon gown enough to leave the nest and perch on a nearby beam.  There, they continued to watch the all hardworking adults and to wait for food to be delivered.

A few days later, the chicks were out of the nest -- but still waiting around to be fed.

This one is a cliffhanger, part two

I was not in any way surprised to see that the birds that returned to the colony under the bridge were swallows.  After all, the nests had looked exactly like swallow nests.  Yet, I did get a big surprise once I started to identify the swallow species.  Not only was the common Barn Swallow (Hirundo rustica) there...

A Barn Swallow (Hirundo rustica) perched under the bridge.

... but so too were the Cliff Swallow (Petrochelidon pyrrhonota)...

A Cliff Swallow (Petrochelidon pyrrhonota) sitting in its nest.

... and the relatively rare Cave Swallow (Petrochelidon fulva).

A Cave Swallow (Petrochelidon fulva) on its nest.

All three species had made their homes under the same bridge and were busy tending to their nests and nestlings.  To be continued...

This one is a cliffhanger

Last September, when I was exploring the park area around my new apartment, I found an abandoned colony underneath one of the bridges over the bayou.

The bridge over the bayou.

Many mud nests had been attached to the concrete columns and beams of the bridge.  However, all the nests appeared empty and some were falling apart.

A couple of empty nests underneath the bridge.

Would the colony residents return, and if so, when?  I doubted that there would be any new activity at the nests until the spring. Indeed, there was little to see under the bridge until April, when the colony members came swooping back.  To be continued...

A dirty job

On the same excursion during which I encountered the strangely attractive crab spider, a fellow walker called my attention to a wasp that was on the path.

A mason wasp (Eumeninae) collecting mud from the ground.

The ground was still moist from rain in the previous days and the wasp appeared to be digging in the mud with its mandibles.  Then, as I was pressing the shutter button of my camera, the wasp suddenly took flight.  By chance, the wasp and the mud ball it was flying off with were caught in the picture.

The mason wasp flies off with the mud ball held in its mouth.

What could a wasp do with mud?  It could build the walls of a nest!  I had seen similar wasps around the house which had done just that.  The wasps had constructed their mud nests in crevices and had progressed to provisioning the nests with food.  In the picture below, you can see a mason wasp's nest in the frame of one of our windows.  Just inside the entrance to the nest, part of a green caterpillar (a.k.a. food for the wasp's offspring) is still visible.

The nest of another wasp, complete with a green caterpillar to feed the wasp's offspring.

Same time, same place, next year

Last summer, we found two song sparrow (Melospiza melodia) nests in the bushes in our yard in Maine.  When I returned to visit this year, the song sparrows were once again conspicuous in the garden -- especially around one of the bushes that had sheltered a nest last year.  Any time I came near the bush, at least one adult sparrow would appear nearby and begin calling loudly.  While trying to keep enough distance to avoid spooking the sparrows, I caught a glimpse of one of the chicks before it hopped back between the dense branches.

A fledgling song sparrow (Melospiza melodia) sitting in a bush.

A few days later, after it seemed the chicks had fledged, I went back to search more thoroughly for the nest.  It did not take long to locate last year's nest again; however, that nest was full of fallen leaves and appeared disused.  A new nest must have been concealed somewhere even deeper within the bush.  In contrast, I found that eastern phoebes (Sayornis phoebe) had been reusing the same nest as last year, with another four chicks successfully fledged this year.

Ants in my pants, continued

Before I was chased away by the wood ants, I caught a glimpse of something metallic and blue pushing up through the sand about a foot away from the stump where the ants had their nest.

Something begins to emerge from the burrow.

This neighbor of the ants was a dor beetle (a.k.a. an earth-boring dung beetle).  Nearly as soon as the beetle had breached the surface, wood ants came running up to inspect their neighbor.

A wood ant (Formica sp.) inspects the dor beetle (Geotrupidae).

Although I thought that the ants might attack the beetle, each one ran off again after a short pause.

Another ant comes and inspects the beetle.

Then, once the beetle had finally emerged from its burrow, it simply turned around and backed down the hole again. 

The beetle safe (?) in its burrow.

Meanwhile, some of the ants were taking more interest in me than they had in the beetle, and so it was time for me to move on.

Ants in my pants

Unlike the ant-hills between the cracks in the sidewalk, the ant-hills that I came across in a nearby park presented real obstacles -- due to their size, the number of ants defending them, and the logs that had been placed around them. 

A wood ant (Formica sp.) nest.

Disregarding the implicit warning of the log barrier, I came closer for a better look at the ants.  The ants were swarming in and out of crevices in the stump where the colony had made its nest. 

A close-up of the wood ants.

Although not quite as apparent in the top picture, the ants had also spread out over the logs and throughout the surrounding area (including where I was standing).  Some of the ants, such as the one pictured below, were returning with captured prey.

A wood ant carries its prey back to the nest.

Meanwhile, a few others were crawling over my shoes, and at least one made it into the leg of my pants before I decided it was time to continue my walk.

Spring cleaning, continued

In between some of the sidewalk cobbles, I found sand piles that were mountains compared to the ant-hills.  There were no ants around these sand piles, nor could I see anything inside when I peered directly down the large, round entrances.  However, as I explored a nearby forested park, I came to the top of a (real) hill that was littered with similar sand piles.

One of the many nests on the hill.

Here, the holes were not all empty.  As I walked along the path, I noticed a quick movement as something disappeared down one of the tunnels.  I crouched nearby and waited -- and after a moment a fuzzy head re-emerged.

A fuzzy head peeks out of the nest.

The occupant of the nest was a mining bee.  Unlike some other bee species (such as honey bees and bumble bees), mining bees are not social.  Each female has her own nest that she provisions with food for her offspring.  Nevertheless, these bees often nest in close proximity to each other.

Two of the mining bees crawling out of their holes.

The two bees pictured above seemed to live too close for their comfort.  Repeatedly, they would crawl forward to inspect each other, then rapidly retreat back into their nests before returning to the surface for another round.

Spring cleaning

Ever since the snow melted off the sidewalks, piles of sand have been appearing between the cobbles. 

Entrances to an ant nest.

Some of these sand piles are ant-hills, produced by ants as they expand their underground tunnels.  Though miniscule to us, some of the sand particles are larger and heavier than the ants.  Nevertheless, the ants are able to carry these particles up and out of the nest, utilizing both their surprising physical strength and teamwork.

Ant workers moving sand out of the nest.

In addition to the ant nests, I found a few sand piles with much larger entrances -- and occupants.  To be continued...

Living between a rock and a hard place

There are a number of rocks and paving stones scattered around the garden.  Every once in a while, I flip one over to see what is hiding underneath.  I usually don't find much besides earthworms and small, dark things that run for cover before I can get a good look at them.  However, one of the rocks I chose to lift recently had been concealing something more interesting: a small colony of ants.
 

An ant nest that was sheltered underneath a rock.

In a cavity beneath the rock, worker ants were attending the larvae.  After the colony was exposed, the workers began to carry the larvae deeper into the colony.  When I looked closely at the larvae, I noticed that they were surprisingly hairy.

You can click on this picture to view a larger version.

Additionally, the larvae appeared to be suspended on a nearly vertical surface.  These two observations may be connected; some ant larvae have hairs that are specially shaped to anchor them to the walls of the colony.

Explore some more: Velcro Hairs Allow Ants to Hang Their Larvae

Surprise inside

Earlier in the year, the crabapple (Malus sp.) tree in the backyard was buzzing with bees.  Now, it is covered in small, sour fruits.  I keep checking the fruits to see if anything will eat them, but so far they have been left alone.  Instead, I have noticed that many of the crabapple leaves are getting rolled up and eaten.

A rolled crabapple (Malus sp.) leaf.

Curious to know what was inside, I began carefully unrolling the leaves.  Within the first few leaves I found white silk, insect frass (the black droppings in the picture below), and ladybugs.

A convergent ladybug (Hippodamia convergens) in a rolled crabapple leaf.

However, most ladybugs are predators, not herbivores.  Something else must have been rolling and eating the leaves -- and then been eaten by the ladybugs.  I kept looking.  On about the fifth leaf, I finally found a leaf roller caterpillar.

A leaf roller caterpillar inside a crabapple leaf.

Having found only harmless (to me) insects inside the leaves, I started unrolling the other leaves with less caution.  However, I soon discovered that the leaf roller caterpillars were not the only ones rolling leaves.  As I peeled open another leaf, I saw long, spindly legs -- and I immediately released the leaf.  I brought a flashlight down to the garden so that I could peek inside through the narrow opening without further disturbing the leaf.  With the aid of the flashlight, I found that the legs belonged to a spider guarding its egg sac.

A spider and egg sac inside a rolled crabapple leaf.

Trespassers will be stung

Whenever I linger too long near the garden gate, I start to get the feeling that I ought to move on.  This feeling arises around the time that a wasp flies up to inspect me.  If I don't immediately respond to the impulse to flee the area, the wasp circles menacingly -- and the impulse grows almost unbearable. 

These "guard" wasps are European paper wasps (Polistes dominula) and they have built several nests on the fence, including right next to the hinges of the gate. 

A European paper wasp (Polistes dominula) guards its nest.

The wasps sitting on the nests are very attentive to anything moving nearby.  Thankfully, the one in the video below stayed on the nest to defend it, rather than flying up to attack.

* To see this video in high definition (1080p), you may need to (1) click "YouTube" to watch on the YouTube website and (2) change the settings at the bottom of the video screen.

When I approached the larger nest, all three wasps turned to watch me.  Unlike at the previous nest, one wasp looked like it was preparing to take flight.  I took this as a signal that I should retreat.  In order to get a better look, I had to come back at night, when the wasps were less easily agitated.

European paper wasps (Polistes dominula) on their nest at night.

A tale of two nests

Three weeks ago, I wrote about two bird nests we had found in the bushes.  One had four eggs and the other had only two.  What has happened since that post? 

Every few days, I would take a quick peek into each nest to see if anything had changed.  A couple of the times that I searched the dense shrubbery for the nest with four eggs, I was startled by a shiny black eye staring back at me.  The parent, a song sparrow (Melospiza melodia), was incubating the eggs.  Then, one day, there were no longer four eggs -- but four almost featherless chicks.  Although their eyes were not yet open, they would open their beaks wide at any movement above the nest. 

Four very young song sparrow (Melospiza melodia) chicks.

Meanwhile, the parents were busy catching insects to feed to the hungry chicks.  Just like the Eastern Phoebe parents, the song sparrows would not approach the nest when we were nearby.  Even if one had caught a juicy insect (as in the video below), it would wait until we were no longer visible before darting into the bushes to deliver the food.

 * To see this video in high definition (1080p), you may need to (1) click "YouTube" to watch on the YouTube website and (2) change the settings at the bottom of the video screen.

The four chicks grew surprisingly quickly and my mother reports that they have already left the nest.  She has heard them chirping from the undergrowth some distance from the nest and seen the parents watching from the trees.

The other nest, with two eggs, had a very different story.  Although I had originally hoped that more eggs would be added, every time I looked there were still only two eggs.  Moreover, the eggs were never being incubated.  It seems that the nest was abandoned by the parents, or perhaps worse -- I had also found signs of an owl in the vicinity of the nest.

A full nest

Exactly how many of the Eastern Phoebe (Sayornis phoebe) chicks were still in the nest?  Standing below, I could see two.  They weren't doing much, but I decided to leave the video camera running as I went off to check the rest of the garden.  When I came back after a few minutes, I once again saw two chicks, sitting very still.  Thus, I was in for a big surprise when I watched the footage for the first time.

* To see this video in high definition (1080p), you may need to (1) click "YouTube" to watch on the YouTube website and (2) change the settings at the bottom of the video screen.

As it turned out, this was the chicks' last day in the nest.  However, the chicks have not gone far: I still hear their "fee-bee" calls from the trees around the garden.

Too close to home

When we found the lost chick, we looked all over the garden for its nest, but without success.  However, when I went to the garage the next day, one of the Eastern Phoebe parents started making its "chip" call at me again.

 

* To see this video in high definition (1080p), you may need to (1) click "YouTube" to watch on the YouTube website and (2) change the settings at the bottom of the video screen.

The bird flitted among several trees in the proximity of the garage and continued to call.  I knew that I must be close -- too close for the comfort of the parent.  Turning back towards the garage and looking up, I finally found the nest. 

An Eastern Phoebe (Sayornis phoebe) nest on top of a column.

It was quite a relief to see that there were surviving chicks!

What I hadn't known before is that Eastern Phoebes commonly build their nests on buildings.  This nest site -- on a column underneath a deck -- should have been one of the first places that we checked.  Nevertheless, it wouldn't have helped to have found the nest the night before.  The nest was too high to reach without a ladder, and any attempt to return the lost chick could have endangered the rest of the nestlings.

The curse of the mummy

This weekend, to explore a bit further afield, I visited a public garden.  While the other visitors were admiring the densely packed flower beds and jotting down the names of plants, I was inspecting the undersides of leaves.  Leaves might not seem to have much to offer when compared to the brilliant colors of flowers and the fast-paced action of the insects that visit them.  However, the plainness of leaves disguises a world of quiet intrigue.

Often, the view from above provides a sign of the action underneath.  Chewed leaf edges are a clue that there may still be a hungry caterpillar below.

A furry caterpillar munches on a leaf.

Meanwhile, folded leaves can shelter a nest.

A female Misumena vatia guards her nest.

Even the leaves that look normal from above may hide a surprising secret.  As the people around me were busy identifying new plants to add to their own gardens, I discovered a mummy. 
 

A mummified caterpillar.

This caterpillar had been mummified by a parasite (likely a wasp).  The developing parasite would have fed on the caterpillar from inside before breaking out of the mummy through the hole that is visible at the top.

Two bird nests in the bushes

When I was growing up, my grandfather would carry me on his shoulders to let me peek into the bird nests he had discovered.  It was always such a thrill to see the delicate eggs in those nests tucked deep between the tree branches.  As the summer progressed, the eggs would hatch and it would become possible to locate the nests by sound.  Though tiny, the chicks would call loudly for food, their beaks opening incredibly wide.

Although now I generally search the garden for insects and spiders, today I was told that I might find one or more bird nests if I looked carefully.  One bird had been acting suspiciously, darting out of a thick bush and running along the ground whenever my mother approached.  Arming myself with my camera, I slowly studied the bush.

Can you see what is hidden near the bottom left corner of this picture?

Suddenly, from between the green branches, I got a glimpse of a nest with four eggs cradled inside.  Luckily, the bird was nowhere in sight and I was able to take a closer look without causing a disturbance.

A bird nest with four speckled eggs.

The adventure then continued at the rose bush.  Once again, I peered at the bush from various angles before finding the one that revealed another small nest...

This nest is not quite as well hidden.

... and two more eggs! 

There were only two eggs in this nest. Maybe there will be another egg tomorrow?