As Predicted!

"In wisdom gathered over time I have found that every experience is a form of exploration."

― Ansel Adams 

I arrived at Pheasant Branch Prairie just after sunrise, my sole mission was to find and photograph migratory sparrows. Although weather reports called for sunny skies, cloud bands to the west were threatening the bright light my antiquated camera needs for effective digiscoping.

The trail that runs along the eastern edge of the prairie is a good location. With the sun to my back, I walk and listen for bird vocalizations, identifying species of interest. Well, I'll photograph anything that perches in good light directly in front of me, like this American Goldfinch.

A Song Sparrow popped into view, thought a somewhat shier subject.

The favored light didn't last for long ...

A large layer of clouds moved in, reducing (changing?) photographing opportunities. 

Even so, I managed to capture some portraits of a dapper Lincoln's Sparrow. The softer light subdues their plumage features a little, but I'll take whatever I can get.

I was considering leaving, but I could see a break in the clouds heading my way.

With blue skies and sunny conditions restored, I came upon a flock of White-crowned Sparrows on the south side of the drumlin. Purists will say, "It isn't a drumlin," and they'd be right. Though it looks much like our region's glacial drumlins, it's actually capped by dolomite bedrock rather than glacial till. It's more geologically correct to refer to it as a drumlinoid. To me, though, "drumlinoid" sounds more like a medical condition than a geological feature. 

 

Anyway, back to the sparrows ...

 There were adults ...

And juveniles ...

But mostly adults.

The complete sparrow species list for the outing:

 

Song Sparrow

Swamp Sparrow

Lincoln's Sparrow 

Savannah Sparrow

Field Sparrow

White-crowned Sparrow

White-throated Sparrow

Dark-eyed Junco 

 

Other birds presents included Yellow-rumped Warbler, Palm Warbler, Orange-crowned Warbler, Eastern Phoebe, American Pipit, Gray Catbird, Tree Swallow, Sedge Wren, Hermit Thrush, American Robin, Northern Cardinal Blue Jay, House Finch, Black-capped Chickadee, White-breasted Nuthatch, Downy Woodpecker, Red-bellied Woodpecker, Northern Flicker, American Kestrel, Cooper's Hawk, Red-tailed Hawk, Ring-necked Pheasant, Sandhill Crane, and Canada Goose.

By mid-morning I was about ready to call it an outing, so I started photographing other things that reflect the present state of the season.

But when one keeps looking, one finds things, like this Gray Treefrog.

A common sight of the season, Blister Beetles were occupying the trail on the south side of the drumlin. I really don't know that much about them. The species is likely Meloe americanus, but I'm not confident of that identification. All I know for sure is not to touch or pick them up. When threatened, as a defense they secrete an oily fluid from their leg joints containing cantharidin, a harsh chemical that can cause painful blisters on human skin.

While it's easy to write-off the slow-moving beetles as boring compared to a lightning-fast, glittering tiger beetle, that reaction overlooks one of evolution's most brilliant trade-offs. Speed requires massive amounts of energy, streamlined bodies, and constant vigilance; tiger beetles have to be fast because they are vulnerable visual hunters like robber flies. Blister Beetles, on the other hand, surrendered speed and flight because they simply didn't need them anymore. Far from being a dull ground-dweller, its sluggish pace is actually an adaptive flex—a quiet confidence born from millions of years of evolutionary mastery where speed becomes obsolete. Though people do accidentally step on them from time to time, given their vast numbers at the prairie, their overall strategy appears to be serving them well. 

And that's it for this week's Nature Post!

Saturday's weather forecast is calling for sunny skies and temperatures in the 80s. I can guarantee I'll likely return to a tiger beetle haunt or two to see which species remain active. 

 

All images © 2026 Mike McDowell

Incomprehensible Distances!

"The Earth is a very small stage in a vast cosmic arena. Think of the endless cruelties visited by the inhabitants of one corner of this pixel on the scarcely distinguishable inhabitants of some other corner, how frequent their misunderstandings, how eager they are to kill one another, how fervent their hatreds. Think of the rivers of blood spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot. Our posturings, our imagined self-importance, the delusion that we have some privileged position in the Universe, are challenged by this point of pale light. Our planet is a lonely speck in the great enveloping cosmic dark. In our obscurity, in all this vastness, there is no hint that help will come from elsewhere to save us from ourselves."

— Carl Sagan

Wow — it's October! 

With last night's cold front, NEXRAD showed a tremendous amount of bird migration. This prompts me to consider a possible sparrow excursion at Pheasant Branch tomorrow morning—perhaps there will be a HASP or LCSP? Given that I've been blogging here for so long (+20 years), when looking at my early October posts from the past, it does seem a bit repetitive and predictable—I tend to do many of the same things over and over by the tick of phenological clock. Another 584 million miles later, should I do the same thing yet again?

Oh, that's the distance the Earth travels around the sun in a year. 

Distance from the Earth to the Sun: ~ 93 million miles

The Earth's orbit diameter: ~ 186 million miles 

Easy math!

So far nothing too controversial, other than the Earth is a oblate spheroid (or more precisely, a geoid).

No ... it is not flat. But they're out there.

Did you know that using the Earth's orbit diameter we can determine the distance of other stars within the Milky Way Galaxy using something called Stellar Parallax?

One uses a big telescope to photograph a star in June, then the same star 6 months later when the Earth is on the other side of its 186 million mile orbit diameter:

The nearby star appears to shift position against much more distant background stars.

The rest is basic geometry and trigonometry.

Ground-based optical telescopes can measure stellar parallax for relatively nearby stars, historically reaching distances of a few hundred light-years. Space-based astrometry, particularly Gaia, extends direct parallax measurements to tens of thousands of light-years, although the uncertainties become much larger at those distances. Radio VLBI can push direct trigonometric parallax even farther, reaching roughly 65,000–70,000 light-years for some radio-bright sources within the Milky Way.

Recall the basic way in which I said we could determine the distance to the Andromeda Galaxy (M31) , our galactic neighbor, by using its arc size against the celestial sphere knowing an approximate diameter of a similarly sized galaxy.

But there's more: Cepheid Variable Stars.

Cepheid variables are giant stars that regularly expand and contract, getting brighter and dimmer as they do. The rate at which they pulsate is tied to how much light they actually produce. The process involves layers of helium inside the star. When those layers are compressed and heated, the helium becomes more opaque and traps more of the star's energy, pushing the layers outward. As they expand and cool, the helium becomes less opaque, allowing more energy to escape, and gravity pulls the layers back inward. The cycle repeats, producing the star's regular pattern of brightening and dimming. By measuring how long it takes a Cepheid to complete one cycle, astronomers can determine its true brightness using the period-luminosity relationship, known as Leavitt's Law. Comparing that true brightness with how bright the star appears from Earth allows astronomers to calculate its distance.

Much like candle light.

Think of a lit candle sending out a sphere of light in every direction. As that sphere expands away from the flame, it gets bigger and bigger. The candle keeps producing the exact same amount of light, but as you step back, that same light is forced to spread thinner and thinner across a larger surface. Because the light stretches out across space in a perfectly predictable pattern, measuring how dim the flame looks to your eye tells you exactly how far away the candle is.

The beauty is that Cepheids not only exist in our galaxy, but others. Thus, we can determine the distance of other nearby galaxies using their Cepheids. With space-based telescopes, this puts the yardstick out to ~100 million light-years. 

100 million times 5.88 trillion miles.

That's this many:  588,000,000,000,000,000,000

And there's still more: Redshift.

Redshift occurs when light from a distant galaxy is stretched to longer, redder wavelengths as the universe expands—much like the pitch of a siren drops as an ambulance drives away:

By measuring the shift in a galaxy's spectral lines, we can determine its redshift. For relatively nearby galaxies, Hubble's Law relates redshift and distance. At much greater distances, astronomers use the measured redshift together with models of the universe's expansion to estimate how far away the galaxy is. This allows astronomers to measure distances far beyond the reach of Cepheid variables, ultimately out to the most distant objects we can observe—46 billion light-years.

And that's how we get an observable Universe that's 92 billion light-years across.

That's 540,960,000,000,000,000,000,000 miles.

We don't know the actual number of galaxies in the universe, but it's estimated between 100 billion and 2 trillion.

Let's say there are 500 billion galaxies, each averaging 100 billion stars within. Since we now know nearly all stars have orbiting planets—our own solar system has 8 or 9 (poor Pluto)—let's assume 80% of stars host an average of just 3 planets.

This is how many planets there would be in that universe:

120,000,000,000,000,000,000,000

120 sextillion planets.

Even if only .000001% of them harbor life, that would be 1.2 quadrillion planets.

Have a lovely day!

Things are Changing!

"It is a century now since Darwin gave us the first glimpse of the origin of species. We know now what was unknown to all the preceding caravan of generations: that men are only fellow-voyagers with other creatures in the odyssey of evolution. This new knowledge should have given us, by this time, a sense of kinship with fellow-creatures; a wish to live and let live; a sense of wonder over the magnitude and duration of the biotic enterprise."

― Aldo Leopold

After morning birding, we decided to return to Sauk Prairie State Recreational Area to see if we could re-find Tmemophlebia coquille, that nifty species of bee fly I discovered the previous weekend. Mark and Dottie wanted to see them and I also wanted to check the tiger beetle situation.

Upon arrival, we relocated them within a few minutes. As far as I know this species doesn't have a common name, so until I learn otherwise we're referring to it as Kiwi Fly. If Callopistromyia annulipes can be referred to as Peacock Fly, what the heck!

Here are some additional facts about them:

• They're tiny: adults are only about 1.5–3.5 mm long—roughly the size of a small grain of rice.
• It's a bee fly, not a bee: Tmemophlebia coquilletti is a member of the fly family Bombyliidae and mimics some Hymenoptera in appearance.
• Its larvae are parasitoids: they develop inside moth hosts, particularly larvae of Gelechiidae and Tortricidae.
• It's a sand-country specialist: Tmemophlebia is associated with sand dunes and other sandy, relatively arid habitats.
• They pollinate Pitcher's Thistle: adults have been observed feeding on this Great Lakes dune plant.

There were one or two Oblique-lined Tiger Beetles out ...

So few remaining!

Truly, a gorgeous early fall day!

It's another great fall for Argiope trifasciata, the Banded Garden Spider.

Here are two different Marbled Orb Weavers (Araneus marmoreus).

We decided to check Baxter's Hollow for birds. Avian-wise, there wasn't much going on except some Red-breasted Nuthatches and the distant call of a Pileated Woodpecker, but we were not expecting the stunning foliage colors. Most everywhere else is pretty green around Middleton, but red, orange, and yellow highlights are beginning to pop.

Poison Ivy above, and American Bellflower below ...

In a moment that was only funny in hindsight, we got back to Middleton and I realized my camera bag was not in my RAV4.

"JFC! Where is my camera bag?"

"Why would have set it down?" she replied.

"To change lenses."

"Okay... so where did you change lenses?"

OMG — Sauk Rec!

Two camera lenses and my Razor UHD 8x32 sat there in the sand for over four hours. Thankfully, nobody stumbled upon my gear, or if they did, they left it right where it was. While I was not thrilled about wasting gas on a return trip, I rarely see this place in the evening.

All images © 2026 Mike McDowell