Why Evolution is True is a blog written by Jerry Coyne, centered on evolution and biology but also dealing with diverse topics like politics, culture, and cats.
Bob Placier’s avocation is bird banding, which he does seriously and diligently. We previously saw his photos about banding adorable Northern Saw-Whet Owls, and now here are some other species. His captions are indented, and you can enlarge Bob’s photos by clicking on them.
I thought I would send along a few pics from my regular banding sessions during spring and fall migration, and a Brown Creeper winter picture from near my feeders. All photos taken here at my home in southeastern Ohio. These are all birds that I uncommonly get here.
Brown Creeper (Certhia americana) – Very widespread in North America, but I get them here only in winter.
Cooper’s Hawk (Accipiter cooperii) – Also very widespread, I catch them when they are in pursuit of songbirds. I capture more Sharp-shinned Hawks (Accipiter striatus), but think that is because the Cooper’s, being larger, get out of the nets more readily.
American Woodcock (Scolopax minor) – Common in eastern North America, and they nest in my vicinity. I watch the males do their mating display on my neighbor’s property each spring. But I have only banded two out of them out of about 23,000 birds I have done to date.
Lincoln’s Sparrow (Melospiza lincolnii) – A boreal bog species, that neither nests nor overwinters in Ohio. But I generally get 1-3 each year during their migrations.
Mourning Warbler (Geothlypis philadelphia) – Another transient migrant in my area, I generally band 1-2 each migration season. A skulker, much sought after by bird watchers.
Yellow-breasted Chat (Icteria virens) – Long considered to be a New World warbler, finally moved to its own monotypic family, Icteriidae, in 2017. An “old field” species, declining in my area as forest succession has reduced that habitat.
Today is Sunday, and that means a batch of themed bird photos by biologist John Avise. His captions and notes are indented, and you can enlarge his photos by clicking on them.
Pelican Feeding Modes
North America has two species of Pelicans: the Brown Pelican (Pelecanus occidentalis) and the American White Pelican (Pelecanus erythrorhynchos). Both have a large gular pouch used to catch fish. But interestingly, these two species otherwise employ completely different feeding techniques. A Brown Pelican spots fish from the air and then plunge-dives head-first to capture the prey in its rapidly expanding pouch. The White Pelican, by contrast, typically hunts in groups while swimming on the water’s surface. Several White pelicans line up with their beaks in the water and herd fish into shallow waters where they scoop them up. In effect, the gular pouches of White Pelicans collectively act like a seine, pinning their prey in the shallows or against an embankment. This week’s photographs showcase these two pelican species and illustrate their distinct feeding modes.
Today’s batch of photos is part 2 of a contribution from from reader Mark Otten (part 1 here), whose IDs and captions are indented. You can enlarge the photos by clicking on them.
Spotted sandpiper (Actitis macularius) This photo was taken by my wife Dianne.
Female wood duck (Aix sponsa) and 7 of her grown ducklings sharing a log with two red-eared slider turtles (Trachemys scripta). The adult female is the fifth duck from the right.
Canada goose (Branta canadensis) at dusk gliding toward a landing.
Lou Jost, working at a field station in Ecuador, has some photos of a recent discovery as well as a video featuring his explanation of the newly seen phenomenon: the production by some plants of fluorescent light. His text and IDs are indented, and you can enlarge his photos by clicking on them.
Most plants look green in sunlight, because leaves reflect green light. But along with this reflected light, plants are simultaneously producing their own light in dazzling colors. This emitted (as opposed to reflected) light is called “fluorescence”; plants are doing the same thing as fluorescent light bulbs, with the sun providing the energy. This fluorescence light produced by the plant is weak and is normally drowned out by the reflected sunlight. However, if we power the plant “light bulb” with ultraviolet light rather than visible sunlight, it doesn’t wash out the fluorescence (because ultraviolet light is invisible), so we can see the emitted colors in all their glory.
I made this video about fluorescence for the Natural History Institute. You can skip the first half: it’s just me explaining fluorescence, but in the second half [JAC: about 6:15] I take you out to see the fluorescence for yourselves.
Here are some additional photos I made of the fluorescence being emitted by some of our local plants. Liverworts are especially brilliant. The green liverwort below is in ordinary sunlight. It’s glowing red but you can’t see that because the sun is too bright. The other photos show just the fluorescence light: the first two show the visible fluorescence, and the third photo is taken with a camera that can also see infrared light, so it shows both the visible and infrared fluorescence.
Ferns are also spectacular. This is a single fern “leaflet”, glowing red, while its spores and their “housings” (sori) glow purple-blue.
Here is grass, fluorescing blue, and lichens fluorescing orange and yellow:
Under natural sunlight, the intensity of the red fluorescence of chlorophyll is strongly correlated with the amount of photosynthesis taking place. Since all the energy expended by living organisms in terrestrial ecosystems originally comes from photosynthesis, the intensity of the fluorescence light can tell us fundamental information– we could measure the total energy input into a given ecosystem by measuring this red fluorescence.
In real life, this seems like an impossible task, since this fluorescence is so faint. However, an interesting consequence of quantum mechanics makes it possible to actually measure chlorophyll fluorescence even from space!!!
Almost all the light that hits Earth comes from the Sun, which is surrounded by a cloud of gas made up mostly of hydrogen and helium. Because these atoms are quantum-mechanical objects, their electrons cannot have just any arbitrary energy; their energies can only have certain special values determined by their quantum-mechanical wave properties. Most photons therefore cannot be absorbed by these atoms, because the photon energies don’t match the allowed energy levels of the atoms. But the photons whose energies match the allowed energy levels of the atoms will be absorbed, raising the atom to higher energy levels. The gas cloud surrounding the sun therefore acts as a filter for the light coming out of the sun; light of certain very precise colors (energies) can’t get through this gas cloud. The same thing happens when the Sun’s light reaches Earth; the oxygen molecules in our atmosphere absorb certain very specific colors.
We’ve all seen the rainbow patterns produced when sunlight goes through a prism. The colors appear to change from red to yellow to green to blue to violet without any gaps between them. But if we looked at that rainbow pattern with a very precise instrument, we would see that there are many tiny black gaps in the rainbow pattern, and the wavelength (or color) of each gap corresponds to the allowed energy levels of the atoms and molecules of the Sun’s gas cloud and the Earth’s atmosphere. The dark lines in the rainbow pattern of sunlight were first noticed in the early 1800s, and are called “Fraunhofer lines”. Here is an exaggerated representation of them from Wikipedia:
Since the spectrum of light coming to the Earth from the Sun is (mostly) lacking these special colors, light that we find on Earth with those exact colors is (mostly) not reflected sunlight. Light of these special colors must have been emitted by the Earth itself, as fluorescence. This gives us a way to measure the fluorescence of the world from space, by looking at the amount of Earthlight that fills these gaps in the spectrum of solar radiation. Specifically, we can measure the red and infrared fluorescence of chlorophyll by finding the gaps (Fraunhofer lines) in the red and infrared parts of the solar spectrum, and measuring the amount of earthlight that fills in these gaps.
People began to realize that this was possible less than 20 years ago. It became a reality with the launch in 2009 and 2013 of satellites designed to use these principles to measure chlorophyll fluorescence. The world chlorophyll fluorescence has now been mapped. This map shows that the humid tropics (like Ecuador where I live) have the highest productivity (biological energy input) in the whole world. Of course, these are also the world’s most diverse terrestrial ecosystems. The amount of photosynthesis happening in an ecosystem is closely correlated with the amount of biodiversity supported by that ecosystem. This is probably not an accident.
We are down to the wire on photos, folks. If you have some good ones, send them to me, lest this feature go the way of the vaquita.
Today’s set comes from Susan Harrison, Professor and Chair of the Department of Environmental Science and Policy at the University of California at Davis. Susan’s caption is indented, and you can enlarge her photos by clicking on them.
These photos are from a single day (April 30, 2020), in fact a single period of around 2 hours, spent at the South Padre Island Convention Centre (yes, they use the British spelling) on Laguna Madre of South Padre island, near the southern end of the Texas gulf coast. It’s a famous location for watching the spring migration, and we were mainly there to see warblers and other songbirds, which were there in abundance. But more surprisingly, the boardwalk at the convention centre yielded close-up sightings of just about every long-legged and long-billed marsh bird you could imagine. Here are the ones I was able to photograph, including 4 rails (including the sora and gallinule), 6 herons (including the bitterns), and a few others. Boy, I would hate to be a frog or small fish in the Laguna Madre!
Today’s photos are of DUCKS, contributed by reader Bob Fritz. His captions and IDs are indented, and you can click on the photos to enlarge them.
Some duck photos taken at Santee Lakes Recreation Preserve in Southern California. The preserve is a water reclamation center and park that provides camping, fishing, boating, hiking and other activities, including bird watching! This is the only location where I have regularly seen Wood Ducks.
Wood Duck (Aix sponsa) – male with closeup and female with closeup:
Today’s photos come from Charles Schwing, whose captions and IDs are indented. Click on the photos to enlarge them.
Here are some game camera pictures of the larger predators photographed at the Archer Taylor Preserve in the western hills above the city of Napa, CA. The picture below shows most of the approximately 400 acres in the Preserve. Caretakers live in the residences at the bottom left and to the right of center.
Above is before the 2017 fires, below is afterward.
The largest predator we’ve caught on camera is an American black bear (Ursus americanus). We suspect the bear is not resident. We get photos only occasionally – once or twice a year.
Not far behind the black bear in size and seen much more frequently (on camera, virtually never in person) is Puma concolor, locally called mountain lion or puma and panther or catamount in other parts of the country.
In the last year or so we have found pictures of two different families. The collared puma (Puma concolor, also called a “cougar”) is P4 (see this very informative site). The uncollared female and her offspring have been showing up frequently enough that we suspect their territories overlap in the vicinity of the Preserve.
The charred trees in the background are what much of the Preserve looks like 3.5 years after the Nuns fire swept through in October 2017.
None of the other predators are nearly as large. Shown are coyote (Canis latrans), bobcat (Lynx rufus), and gray fox (Urocyon cinereoargenteus).
Once again, send it your good wildlife/street/travel photos. The tank inexorably drains towards zero. All readers’ comments and IDs are indented, and you can enlarge photos by clicking on them.
Today we have a potpurri from several readers. We’ll start off the with a video from Jonathan Storm, a biology professor at University of South Carolina Upstate.
This female Ruby-throated Hummingbird [Archilochus colubris] was collecting spider silk from a window on my house in South Carolina. The sticky and stretchy nature of the silk help hold the nest together and anchor it on top of a tree branch. Ruby-throated Hummingbirds often construct their nest from dandelion seeds, moss, and lichens and place it high up in a hardwood tree.
Here is one of a Cedar Waxwing, Bombycille cedrorum, one of a nesting pair in Champaign County, Ohio, the photo taken on June 8, 2021. An adult Cedar Waxwing is near the pinnacle of feathered elegance.
From Diana MacPherson.
Here is a black variant of the Eastern Gray Squirrel (Sciurus carolinensis) on my feeder this afternoon. I like how the squirrel sits under the wire holder.
While driving south along the western shore of the Columbia River going from Lake Chelan to Wenatchee, I inadvertently looked up at the hillside I was about to pass and was rewarded with the sight of a Bighorn ram standing on a dirt roadcut overlooking the river. I stopped, dug out my camera, then walked back to get a decent photo.
Having lived in Washington for most of my 80 years, this is the first Bighorn sighting I have witnessed. They were driven to near extinction by 1920, primarily by disease transmitted through domestic sheep. Overhunting and habitat loss is usually cited as contributing reasons, although it is hard to see how either could be a major factor prior to 1920, and no evidence is given. There is abundant evidence that the mycoplasma bacterium (sheep pneumonia) is found in and transmitted by domestic sheep allowed to graze on Federal lands. One infected Bighorn lamb corpse was found in October, 2020. Later that month a lost (and infected) domestic ewe was found in the Bighorn’s range.
Today there are 17-18 herds and they number somewhere around 1700-1800, although they are threatened by the disease, which has been said to have killed up to 98% of a population. These gorgeous creatures are in, but not out of, the woods.
From Christopher Moss:
Continuing my life under house arrest with my brand new immune system, I keep looking out and spying new friends, like this red fox cub [Vulpes vulpes] who has discovered there are spilled sunflower seeds under the bird feeders. The cutlery? A windchime made by a friend that one is obliged to hang somewhere…
Today’s selection comes from Rachel Sperling, whose notes and IDs are indented. Click on the photos to enlarge them.
Apart from the video, these were all taken in Connecticut and the New York section of the Appalachian Trail, which I’m hiking with a friend.
A pair of mute swans (Cygnus olor) on the reservoir near my house.
A pair of black vultures (Coragyps atratus) amid some glacial erratics in northern Connecticut. I think this is a bit north of their normal range. I used to see them fairly often when I lived in Maryland.
Canada goose (Branta canadensis) on Lake Zoar in Connecticut. Nothing terribly exciting about a Canada goose, but this one was sitting on some eggs, and it was around Mothers’ Day, so I thought it was sweet.
A couple of millipedes (Apheloria virginiensis) on a trail in Sharon, Connecticut. The one on the right is giving a ride to an inchworm, but I’ve no idea which species of Geometer moth it might be.
Finally (for now – I’ll be back on the trail this weekend, I hope!) here’s a video I took back in December of 2017, when I was living in New Hampshire. My cat Lloyd (Felis catus) was intensely interested in a supremely unruffled American goldfinch (Spinus tristis). I don’t know much about bird intelligence, apart from what I’ve read about crows, ravens, and parrots, so it surprised me that the goldfinch would understand that it was safe from the cat.
Here are some travel photos by Joe Dickinson. You can enlarge them by clicking on them, and Joe’s captions are indented.
Here is a second set of my favorite photos.
This is a diverse collection of cacti in Baja California.I can’t identify the species.
This is a campsite in Nine Mile Canyon, Utah, with my wife and our dog, Ruby. We purchased the camper van when I retired in 2002 and passed it along to her brother-in-law just a few months ago.
Oregon coast near Canon Beach:
The Disney Concert Hall in Los Angeles:
Our Granddaughter, Erin, on Hilton Head Island, South Carolina.I always imagine her saying “I hereby claim this land in the name of…” We just attended her high school graduation. Time flies.
My wife and I on the stairs down to Point Reyes Light.
Kolob Canyon in the redrock area of southern Utah, winter.
Multnomah Falls along the Oregon side of the Columbia Gorge.We plan to cruise that canyon in a few months.
A personal indulgence if I may.I am an amateur horn player and had just received a replica of an early 19th century horn of the type that Mozart and Beethoven wrote for, pictured with some typical music written for horns in that style. The smaller circle is one of a set of interchangeable “crooks” that put the horn into different keys.
Another shot along the Oregon coast, near Coos Bay, I think.
Our dog, Ruby, in deep snow at a cabin we had in the Wasatch mountains near Salt Lake City.She had, shall we say, an unfortunate affinity for snow.
Finally, a view from Zabriskie Point in Death Valley. [JAC: I spent a lot of time in this locality while collecting and releasing flies in California, and there’s a movie called “Zabriskie Point” filmed by Antonioni in 1969. It’s not a very good movie.]
