The Invader

Florida has the distinction of being the epicenter of invasion of non-native reptiles, introduced by collectors who intentionally or unintentionally let non-natives escape, or by accident when eggs or small hatchling reptiles are carried into this country on imported plants.

The Cuban Brown Anole is a 5-9 inch slim lizard, marked with a diamond-shaped pattern on its back. It typically rests in low vegetation, waiting for unsuspecting insects — or other, smaller lizards — to walk by, and then quickly gobbles them up.

Successive invasions of Brown Anoles from Cuba and the Bahamas since the late 1800s have resulted in well established populations throughout Florida that have since moved north and west to Georgia, Louisiana, and Texas, and have also resulted in an apparent coincident decrease in the population of native Green Anoles.

Brown Anoles now occupy the tree trunk-ground niche in their hunt for prey, and occur in very high density in residential shrubbery (sometimes 4-6 to a single bush).
Female Brown Anoles (recognized by the brown stripe down the middle of their back) lay 1-2 eggs in leaf litter or potted plants every few days. Eggs hatch 4-6 weeks later, and the 1-inch long hatchlings move into the vegetation to hide from larger individuals that might eat them.

However, rather than disappearing altogether as a result of the Brown Anole invasion, it may be that Green Anoles simply move out of the low vegetation and up into the tree tops where they can more favorably compete for food and avoid being eaten by the more aggressive Brown Anole.

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.

Birding is such hard work

We sit quietly in chairs placed strategically near bird feeders, waiting expectantly with cameras on laps and binoculars glued to eyes, searching for that iconic shot of some new bird we’ve never seen before, or a better shot of a bird we have seen many times before. When we’ve exhausted the possibilities at one site, we get in the car and move on to the next one. It’s such hard work…(not). But it’s the thrill of the hunt for the best shot that keeps us going from place to place.

From my chair I could see hummingbirds coming to any one of six feeders (two shown here), but most were too far away to get good close-ups of the action. Oranges, jars of grape jelly, platforms with seed, and containers of suet mix were spread out in the trees in front of us — a real bird buffet. All we had to do was sit and wait for birds to show up.

In Portal, Arizona, in the foothills of the Chiricahua mountains, you are welcome to visit the backyards of the local residents to sit and photograph the birds that visit their feeders. At this particular backyard, a Roadrunner (lower left of the photo) walked through the backyard looking for an unwary bird to capture. It made a half-hearted attempt to lunge at a hummer on one of the feeders in the photo above, but gave up and moved on. We heard it had grabbed and eaten a Cactus Wren just a half hour before.

This is a collage of the Broad-billed Hummingbird’s approach to the feeder. If the bird catches the light just right, it shows off it’s beautiful iridescent blue and green feathers. Photos taken at 1/2000th of a second stop the rapid wing action as the bird hovers in place. Click on the image to view it in full screen.
Even though the feeder is large in comparison to their size, hummingbirds aren’t very tolerant of others trying to feed at the same time they are. Here, a female Blue-throated hummer feeding on the left is much larger than the approaching make Broad-billed Hummingbird, and just her presence there is enough to make him hesitate to settle on the feeder.

the tiny garden

A taste of spring hit the backyard as temperatures soared into the 60s the other day, and major amounts of snow melted. When I walked into the wetland beyond the backyard I was greeted with signs of life awakening after the long winter — like this tiny garden on a rotting log.

A tiny one-inch across mushroom nestled in among several different species of moss. Spore capsules of moss tower above the green vegetation — the better to spread their tiny spores to a new site on the log.
A second, even tinier mushroom is growing beside the bigger one. If I knew something about moss, I could tell you how many different species there are here in this 4 square inches of log.
A veritable forest of mossy leaves support the towering trunks of the sporophyte part of the plant with its knobby capsules waving in the breeze.
Meanwhile, a pair of Mallard ducks, keeping a close eye on me as I walk by, is taking advantage of early snow melt to rest in a shallow pond.

Fall reminiscence

After four days of the white stuff raining down on us, I need a shot of color from the brilliant hues of this past Fall season.  

Late in the summer and early fall, the dominant color in the prairie garden changes to yellow as several species of Goldenrod bloom. The yellow blooms and rust-brown grasses of this prairie are accented by the flowers of several aster species in shades of blue to purple.
Here is a feast of nectar and pollen for bees, and the flowers blooming this late in the summer and fall have their undivided attention.
Five-foot tall Maximillion sunflowers are just one of many sunflower species that bloom in the fall.
A New England Aster blooming along the sidewalk to my front door was a magnet for bumblebees, honeybees, and at least two species of syrphid (hover) flies.

One way to ensure seed set in a plant is to capture as many pollinators as possible, and this seems to be the strategy influencing the flowering times of Goldenrod and Aster species. By blooming so late in the summer and early fall, they are pretty much the only pollen and nectar sources around.

And to ensure that bees do visit their copious numbers of flowers, the plants need to advertise themselves with the colors that are most attractive to bee eyes — yellow-green and blue-purple. Bees also key in on light that is a combination of yellow and ultra-violet, something humans can’t detect, but probably marks landing platforms or serves as nectar guides on flowers.

Summer’s brilliant colors fade in the fall as the landscape transforms. It will be another 8-10 months before I can enjoy scenes like this again.

Transition

We went from fall to winter in two hours this morning.

After a second round of leaf raking and mowing, I admired the fall colors of the garden. But not for long.

Two hours later, it looked like this.

You can’t really tell how hard it’s snowing from this wide-angle view.
Individual flakes form a cloud over the vegetation.
This isn’t even close to a white-out, but it’s enough precipitation to discourage the backyard birds and squirrels from visiting their favorite feeder.
Snowflake tracks look like rain, visible as white streaks.

Goodbye to Fall — it seems a little early for winter’s first appearance, but this is 2020 afterall, when the unexpected has become the norm.

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

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.

It’s time for lilies!

Walking around the neighborhood the other day, I found a variety of lilies in bloom in my neighbors’ gardens.  Together they make an amazing bouquet of color (click on the image to get a full screen view):

Many of these lilies are hybrids of Asiatic varieties, but there are about 90 species in the genus Lilium, so there is plenty of natural variation.  The American Tiger Lily is one of those beauties.

Yellow or orange with dark purple spots –you can see where it got its name.  Black pollen sacs may drop pollen on the chocolate brown stigma (female) surface, or bees, butterflies or birds may help distribute the pollen as they visit the flower.

Unlike most flowering plants, lilies don’t seem to have a lot of pollinator visits, but they don’t really need them since they are self fertile and can produce seed sexually by that process alone.  They can reproduce asexually as well, by budding off of the basal bulbs from which stems and leaves grow in the spring.

The Asiatic lily in the foreground has just opened, and the pollen sacs on the anther are not yet open. The anther reflexes 90 degrees from this position to present the pollen for distribution by pollinators or wind (like the anthers on the lily in the background).

This bumblebee roamed around the base of the day lily, perhaps hoping there was nectar there, but immediately flew off. Bees seem to “know” that lilies are not good sources of nectar.

In contrast, little syrphid flies (hoverflies) immerse themselves in pollen in the process of trying to eat it, and can help cross pollinate lilies.

The only downside of these gorgeous blooms is their relatively short lives.

Bring on the bees

It’s prime time for summer flowers, and the bumblebees and honeybees are making the rounds carrying pollen from one flower to another and sipping nectar as their reward.

Tubular flowers of red bee balm (Monarda) are perfect for a slender honeybee or the long tongue of butterflies and hummingbirds. The nectar is deep down at the base of the flower, so it’s an effort for a small bee to get there.

Lead plant flowers open sequentially on a long raceme (flower stalk) exposing their yellow orange anthers to wandering bumblebee that collect and store pollen in sacs on their hind legs.

Milkweed flowers have special requirements of their pollinators — they need to stick their legs down slits in the female (pistil) parts of the flowers and drag out the pollen sacs (pollinia) on their hind legs. The slender leg of a honeybee is the perfect vehicle for this operation.  When they wander onto the next flower, the pollinia will get transferred as the bee’s leg drops into the appropriate slot.  To read more about how this is done, click on this link.

Bees love the pollen of the Cup Plant, a tall composite (daisy) with an abundance of bright yellow flowers.  Later in the summer, the Goldfinches will appreciate the fruits (well, seeds) of these pollinating efforts.  

In the fall, Goldfinches dissect the Cup Plant flowers, pulling the seeds right out of the flower head. Fortunately, there is a great abundance of flower heads to work on, and there are plenty of seeds left for the plant to fill up by backyard garden with its progeny.