Color me green!

When I went out to pick raspberries this morning, I found something much more delightful than a bunch of mating Japanese beetles (the scourge of the berry patch!) — a couple of 1-inch Gray Treefrogs hiding in plain sight on the green leaves of the raspberries.

From the side, this little one with its dark facial markings and dark lateral stripe was more obvious.

Although this species is named the Gray Treefrog, because they are quite gray with a dark blotchy pattern sometimes, in bright sunlight on a green background, they are well camouflaged as they match their background. In fact, this frog even matches the particular shade of green of the raspberry leaf on which it rests.

I wonder if they eat Japanese beetles? There are plenty of other insects resting on the raspberry leaves for these little guys to dine on. But these frogs are really only active at night, and usually seek shaded vegetation for their daytime rest.

The color matching camouflage is impressive in both the shade (this photo) and the sun (photo above).

How exactly does a gray treefrog become green?

Looking more like the gray treefrog, I photographed this maxi-sized (2.5-inch) adult in the early morning while it was sitting under an evergreen in the leaf litter.

Frog skin contains a stack of color-producing cells called chromatophores, and many frog species like the Gray Treefrog, have 3 sets of them: a deep layer called melanophores that contain a black/brown pigment called melanin, an intermediate layer called iridophores that lack pigment but contain particles that can reflect blue light, and an upper (most superficial) layer called xanthophores that contain yellow pigment.

Now, it should be more obvious how a Gray Treefrog can transform quickly from its gray color that is produced by the dispersion of deep-lying melanin pigment to a bright green color, produced by the interaction of blue-reflected light from the iridophores passing through the yellow pigment of the xanthiphores (i.e., blue plus yellow equals green to our eyes).

The dispersion of pigment in frog skin is controlled by nerves and hormones, which act on the chromatophores to aggregate (condense) or disperse pigment. Physiologically, in a matter of seconds, when melanophores aggregate their pigment to uncover the iridophores and xanthophores disperse their pigment, a gray frog turns green!

Color changes can even happen while frogs are sitting in the dark in my covered water tank. It just depends on their physiological state, the temperature of their environment, and the amount of hormonal or nerve stimulus they are experiencing.

Blooms in the backyard

In the Minnesota backyard, some of the summer blooms are in their full glory, particularly the purple coneflower. Butterflies and bees are drawn to these flowers…

A Great Spangled Fritillary stopped by…

And examined each of the disk flowers in the flower head intensively.

I caught the approach of one of the honeybees buzzing the coneflowers.

And was able to zero in on the bee when it landed.

Even the Goldfinches were checking on the flower heads, I suppose to see if they had made any seed yet. But these flowers have just opened up in the last few days.

at the beach

It seems like when we’re not in the mountains, we’re at the beach. That’s the wonderful thing about California — the variety of places to explore. This time it was the beautiful sands of Pajaro Dunes, where the gently sloping shore allows you to walk far out into the waves and not even get your knees wet.

The grandkids enjoyed the ocean and the bird life, and especially skipping rope with a giant piece of brown kelp.

Running with the Ring-billed Gulls

This is good practice for jumping creeks in the Sierras later this summer.

Brown Pelicans catching an updraft from the wave action.

Digging for clams — it was fun finding them, but this was strictly catch and release.

As soon as the clam was placed back on the sand, its muscular foot began digging it back under the surface again.

In just a few moments, the clam had almost completely required itself (note sand spray from its “foot” at the bottom of the image).

Grassy vegetation on the dunes holds some of the sand in place. These dunes were a lot taller than they appear, and the sand was quite deep. A single stand of brown kelp provided many minutes of entertainment…

Ghost ship

One of the landmarks of the Santa Cruz coastal area in California is the wreck of the concrete ship at Seacliff beach. When we visited the beach in the early morning fog, the ship appeared ghostly and mysterious, except for the hundreds of birds that have made the deteriorating framework their roosting area.

The ship is broken in half and sinking into the bay here, but there are ample structures above water for roosting Brown Pelicans, Double-crested Cormorants, Ring-billed Gulls, and lots of Pigeons.

Hundreds of birds perch on exposed rebar from the deteriorating concrete.

Cormorants and Pelicans fly to and from the ship on hunting trips for fish, but they almost disappear in the fog.

It’s a ghostly sight as it disappears into the thick fog layer on the beach on this particular morning.

The cement ship, SS Palo Alto, (weird construction material for a ship!) was commissioned to be built as an oil tanker in WW1 in 1919, but the war ended before it made its maiden voyage. It was then towed to this area along the Monterey Bay coastline in 1929 and served as an amusement park/entertainment center, with a casino, dance hall, arcades, etc., until its owners went broke during the Depression in the 1930s.

Both the ship and the pier it once attached to are rotting away, but their remains make for some interesting photography.

On this foggy morning, the sky and the sea blend into one another. Few people are out on the beach to “enjoy” the sights.

Jewel of the Sierra

It’s either the “flame of the forest” or “gleaming jewel of the mountains”, but there is no doubt that the Western Tanager male is a stand-out of brilliant color in its forest environment.

Male Western Tanagers sing a pretty little song as they dart around their territory, flitting from tree to tree.

Western Tanagers, which are members of the Cardinal family (not the tanager family), range as far north as southwestern Alaska and western-most Canada south to Baja California during their breeding season, sticking primarily to western coniferous forests or mixed coniferous and deciduous vegetation. They build a nest in the open canopy and raise their brood of 3-5 chicks on a variety of insects, from wasps and ants to caterpillars and dragonflies. But in the fall and winter, they become fruit specialists in their neotropical wintering areas, like other tanagers there. In fact, they were considered to be serious pests of cherry orchards in the late 1800s.

The handsome male derives his rich red feathers from an insect pigment called rhodoxanthin, unlike other orange to red colored birds which must consume the carotenoids that color their feathers from plants.

it’s always a treat to see one of these bright, flame-colored birds, especially close-up!

Family time

While walking along the road down to Fallen Leaf lake from the cabin, we came across a mama White-headed Woodpecker feeding her babies. Her nest was right on the road, just 10 feet off the ground in a broken stump of a Jeffrey pine.

There were several holes in this stump, so perhaps it had been used as a nest site before. In this species, the male chooses the nest site, but females get to choose whether they like his location or not. Both male and female excavate the nest hole which is usually about 8 inches deep.

The chicks were quite vocal, peeping almost continuously, and you would think a predator might cue in on that. The chicks seem large enough to be near fledging at this point. Reddish feathers on this chick’s head indicate this nestling is a male.

Some juicy green insect material being delivered to the nestling…

Open wide, down it goes. White-headed Woodpeckers are actually pine nut specialists, and pick the seeds from the cones, then fly to the trunk of the pine, wedge the seed in a crack and proceed to hammer on it until they break the seed apart. However, the chicks get fed an insect diet.

These woodpeckers are year-round residents of pine forests in the western-most U.S. states from Washington and Idaho south to central California Sierras. The pair share egg incubation duties (rather rare in birds) and communicate with each other all year by drumming.

And she’s off again to find some more tasty morsels for her brood.

Uh oh, someone else is checking out this stump for a nest site…a male Hairy Woodpecker.

Mr. Hairy peeks in for a few moments but leaves the nestlings alone.

A hike in a Sierra meadow

There are lots of trails to explore in the Lake Tahoe basin, and we took the grandkids on a “walk” from their cabin on Fallen Leaf lake all the way to a swimming beach on Lake Tahoe — an almost 7 mile hike. Naturally, there were a number of stops to rest and swim at places along the way, and there was a promise of ice cream at the end of the hike, and that’s all it took to get the kids there.

The water of Fallen Leaf lake is as clear as that of Lake Tahoe, but right now the water near shore is more of a greenish color due to all the pine pollen accumulating there. If the glaciers that created it had continued to carve their path from the Glen Alpine valley, this lake would simply be a bay of Lake Tahoe.

The trail along the east side of the lake wanders through countless meadows and stands of Jeffrey pine (the one that has a scent of vanilla wafting from the cracks in its bark). The tall meadow lupine was in full bloom.

Another blue-purple flower that I thought was forget-me-not turned out to be Pacific Hound’s Tongue, so named for the shape of its basal leaves that resemble a dog’s tongue. The flowers were loaded with small Two-banded Checkered Skipper butterflies feasting on nectar.

Juncos are already far along in their nesting cycle, feeding their rapidly growing chicks.

A Red-breasted Sapsucker checked us out as we walked under him on our trek by the salmon run on Taylor Creek. I wonder if this is the same bird we saw here in April at this spot?

White-headed Woodpeckers are somewhat common in the pine forest here in the Tahoe basin. This female was feeding chicks in the nest (on her left) and not at all shy about us walking near her.

another little bird at the slough

I went back to the same place in the Grass Lake slough where I found the Solitary Sandpiper the other day, and found a juvenile Green Heron fishing for its lunch in the duck weed scum.

A bumper crop of Green Herons were produced in the backwaters of the Grass Lake slough this year. This is one of 8 individuals I saw on this particular day (all in different places in the slough, so no repeats).

After a few minutes of watching the heron change locations, look around, and waiting for it to catch something…

Out of the corner of my eye, a little brown and white bird trotted out in front of the heron, and proceeded to walk toward me, quite unafraid.

Killdeer are distinctive brown and white birds with a broad black neck band and red lining around the eye. But even more distinctive is the trilled “kill-deer” made over and over as a warning or an announcement of their presence that you frequently hear on gravel paths or large expanses of short grass where they forage.

But eventually the bird walked too close to me and realized I wasn’t an inanimate object.

Too close for comfort, and then the inevitable, quick take-off…

Faster than you could move the camera, the bird was out of the frame and off to better foraging spots, calling “kill-deer” over and over as it flew.

look-alikes (and not)

The Grass Lake slough at Snail Lake regional park is teeming with butterflies, especially Monarchs, which may be congregating here for their southward migration.  The Monarchs especially seem to like the meadow blazing star and don’t even mind sharing it with a lot of other butterflies, bees, etc.

The number of flowers present on meadow blazing star is one reason that butterflies congregate on it. The fact that it provides a lot of nectar at a time (late August) when butterflies are migrating is another.

Plenty of nectar to go around for Painted Ladies (also migrating by the thousands in late summer), Monarchs, bumblebees, honeybees, and a few stray beetles.  The orange, black, and white pattern of the Painted Lady is similar to that of Monarchs, but they are not mimics and the two are easily distinguished from one another.

But one of the many Monarch butterflies I photographed wasn’t a Monarch, but a Monarch mimic, the Viceroy, and these two unrelated species ARE difficult to tell apart.  Can you spot the difference(s)?

Both species exhibit the bold orange and black pattern on the wings as well as the pattern of white dots on the black head and thorax of the insect. 

The biggest difference in coloration of the two species is the bold black horizontal (sort of) stripe on the hind wing of the Viceroy, seen from above or below.  The thick black lines on the hind wing of the Viceroy are similar to those of a female Monarch but are much bolder than the male Monarch’s, which also has a distinctive dot on each hind wing.  In addition, Viceroy butterflies are smaller in size, only about 2/3 the size of a Monarch.

But where Monarch caterpillars grow up eating milkweeds containing poisonous cardiac glycosides which they sequester in their bodies (and wings), Viceroy caterpillars eat willow, poplar, and cottonwoods — not at all poisonous. Bird predators find Monarch butterflies extremely distasteful and will regurgitate or spit them out. Viceroy butterflies that most closely resemble their poisonous cousins in coloration are better protected from predation, and thus, the mimics survive to reproduce.

And then there are these two, apparently dissimilar butterflies, flitting around the same plants, often displacing each other from the same flowers.

The Eastern Tiger Swallowtail comes in two colors: yellow and black, and black.

Not at all look-alikes, in fact, color-wise, they couldn’t look more different, except for the pattern of white dots around the margin of the wings and the distinctive iridescent blue splashes of color on the back end of the hind wings.  So, what’s going on here?

Male Eastern Tiger Swallowtail butterflies are almost always yellow with black stripes.  Females on the other hand vary between yellow morphs and black morphs.  And, the black morph is more commonly found in the southeastern U.S. where a similar-colored, poisonous and unpalatable Pipevine Swallowtail butterfly occurs.  These are the “look-alike” models for the Tiger Swallowtail (and other Swallowtail butterfly species) to copy.  Interestingly, the proportion of female black morphs of the Tiger Swallowtail is higher in southern populations because of genetic (sex-linked) process that makes black morph females produce mostly black morph females, and yellow females produce mostly yellow females!

Bottom line:  you have to look closely when identifying a butterfly, because it might be a mimic!

Comparison of three common swallowtail butterfly mimics and their model, the Pipevine Swallowtail. From butterfliesathome.com

return of the big, scary black wasp

I haven’t seen the Great Black Wasp (Sphex pennsylvanicus), a type of digger wasp, for eight years, when I first found this fearsome looking insect in my backyard feasting on the nectar of swamp milkweed.  But this week I found several of them pollinating the flowers of a wildflower I have never seen before — Spotted Bee Balm.

A 1.5-inch long, fearsome-looking all black wasp with long legs and blue-black wings.  

The wasp inserted its head all the way into the flower and came out again with a nice dusting of pollen to take to the next flower.

The Great Black Wasp is also known as the Cicada Killer, for its habit of stinging and paralyzing orthopteran insects (grasshoppers, cicadas, etc.) to provide food for their offspring.  The prey are paralyzed after being stung in the head and abdomen and are then deposited in an underground nest. A single egg is laid on the underside of just one of the two to six prey items placed in each nest chamber as the larva’s food source during its development.

Spotted Bee Balm is a relative of the more common pink or red Bee Balm.  Flowers are arranged in whorls along the stem of the plant.  Multiple stems bearing flowers present a rich source of nectar and pollen for pollinators, but the stems die back in the winter, and the plants regrow from the roots only 1-2 years before dying out.

White bracts separate clumps of flowers on the stem and the flowers seem to open sequentially rather than all at once, so pollinators would be encouraged to revisit particular stems and whorls of flowers.   

This fragrant flowering plant, found mostly in the eastern half of the U.S.,  is especially attractive to large-bodied bumblebees, carpenter bees, and digger bees, as well as a variety of other nectar- or pollen-feeding insects.  It flourishes in dry, sandy areas, disturbed areas along roadsides and railroads, old fields, and prairies.  I don’t know why I have never seen it before this, but I would certainly like to add it to my prairie garden.

Wildflowers at the Grass Lake slough include a wide variety of perennials like Spotted Bee Balm.