Can You Find the Nest? A Near-future Killdeer Family on the Tuolumne River

The Killdeer (Charadrius vociferous) is a sneaky little bird that hides in plain sight. That sounds like some kind of negative judgment, but really I admire these little Plovers. I wonder sometimes how the species survives, given their habit of building nests right out in the open on stony ground, within easy reach of all manner of predators. And yet somehow they persist.

We watched a nest last year at the Great Valley Museum's Outdoor Nature Lab. This year, the Killdeer nest I "found" is along the Tuolumne River Parkway Trail, but not so much on the trail as on the grounds of the Waterford water treatment plant. They have gravel roads around the aeration ponds, and that's where the Killdeer put its nest. Luckily a city worker noticed and put up a traffic cone to protect the nest from being run over.

If a threat presents itself, the Killdeer will make a lot of distracting noises and actions. The Killdeer are famous for their broken-wing act by which they draw a predator away from the nest. And as you can see from the picture above, the eggs themselves are well-protected by camouflaged coloration.

I found myself wondering how the eggs avoid being fried by the sun in their rocky nest out in the open, but if you look at mama Killdeer watching her nest, you'll notice she is shading her eggs, not sitting on them.

I missed the hatching last year, but if the stars align I might get to see the babies this year, seeing as how my summer field classes got cancelled, and we are still on a shelter-in-place order. We'll see.

A final note...if you are wondering if I was invading the personal space of the bird in this picture, I was actually on a bluff around a hundred yards away. I love the zoom lens on my camera!

Civilization Exists By Geological Consent...So does life in the Great Valley

Sandhill Cranes at the San Luis NWR

The Sandhill Cranes are returning to their winter home in the Great Valley of California! In the next few weeks there will be 20,000 of them arriving at the Merced National Wildlife Refuge a few tens of miles south of Modesto. They will be sharing space with hundreds of thousands of other birds, including Snow Geese, Cackling Geese, Ross' Geese and many others. To many pundits, the Great Valley of California is a rotten place to live (see my comments about this from yesterday's post). But if you are a bird, the valley is next to paradise. It represents survival, and the reasons are geological.

Sandhill Cranes at the San Luis NWR

The Great Valley is 400 miles long, and around 30-40 miles wide, running from Redding at the north end to Bakersfield in the south. It is amazingly flat, with total relief of only a few hundred feet. Two major river systems, the Sacramento and San Joaquin, provide a richness of water in what would otherwise be desert or near-desert. A huge range of habitats existed here at one time, including short-grass prairies, riparian floodplains, oak woodlands, lakes, and vernal pools. Although agriculture and urban development have co-opted some 95% of the valley floor, there are still pockets of native environments remaining.

Killdeer at the Merced NWR

The valley originated as a large shallow sea called a forearc basin along the vast subduction zone that once existed across the entire west coast of North America. The convergent boundary was eventually changed, and the San Andreas transform took its place. The Coast Ranges rose in the last few million years, acting as a rain shadow, and preventing the rivers from finding an easy path to the sea. The Sacramento and San Joaquin rivers flow outward through the Carquinez Strait, but several other rivers, including the Kings, Tulare, and Kern, don't reach the sea. Prior to settlement and diversion of the rivers for agriculture, they ended in large shallow lakes at the south end of the San Joaquin Valley. The lakes are dry today.

Yellowlegs (Greater?) at the San Luis NWR

Though so much of the original valley habitat is gone, a few critical wetlands remain and are preserved as a string of National Wildlife Refuges. These refuges are a critical component of the migratory flyway for millions of birds. Some simply pass through, stopping long enough to eat and gather energy for their long journey, but others spend the winter here, and some stay all year.

California Quail at the San Luis NWR

Many tourists pass through the Great Valley without a second thought on their way to Lake Tahoe, Yosemite, or Sequoia/Kings Canyon, but at this time of year they are missing an awesome show of the variety and diversity of nature. There is nothing quite like seeing and hearing the spectacle of 10,000 geese taking off all at once. There are hundreds upon hundreds of bird species who spend at least part of the year in the valley, not to mention a rich variety of mammals, reptiles, fish and amphibians. The valley for all its problems can be a fascinating place to spend some time.

Great Blue Heron at San Luis NWR

The San Luis National Wildlife Refuge Complex includes 45,000 acres of protected lands within an hour's drive of Modesto, my home base. There are a number of hiking trails (all level, imagine that!) and several auto tours, including those at the San Luis and Merced Units where I took all of these pictures today. I think we saw or heard at least three dozen species of birds in just the four hours we spent exploring.

Northern Shovelnose at the Merced NWR

We were entranced by the hundreds of Sandhill Cranes arriving by the minute in the setting sun. The video below provides a sense of how it felt...

Don't just pass through the Great Valley on your next trip to California. Check out our valley and find out why we call it "Great". Two places to get information: the headquarters for the San Luis NWRC near Los Banos, and in a few short months, the Great Valley Museum on the west campus of Modesto Junior College. 

The title quote comes from Will Durant, and in its entirety reads "Civilization exists by geological consent, subject to change without notice".

The Birds of My Neighborhood: Geotripper Explores the Home Base

These pictures will be familiar to my Facebook friends who have been subjected to several weeks of wintertime explorations of my neighborhood looking for our local bird species. I've always liked birds, but I've lacked a camera with sufficient zoom to capture them easily, and I am pretty bad at remembering names and species. I've been surprised at how many different species can be seen during short walks around the block and through the nearby cow pasture (although I shouldn't be; we live in prime wintertime bird habitat).

The first, and one of my favorite recent pictures, is a Western Scrub Jay (Aphelocoma californica) making a meal out of a pecan. The scrub jays are obnoxious and raucous, and at constant war with our cat in the backyard, but they are also a bright splash of color, and are one of my favorites.

The Snowy Egret (Egretta thula) is a fairly common wetlands inhabitant in our area. They are one of the most graceful birds I see on a regular basis, standing very still will getting ready to stab at fish or amphibians in shallow water (like they did when they got the goldfish in my pond...).

I keep a feeder in the backyard, and it attracts three or four varieties of finches, including the House Finch (Haemorhous mexicanus), the Goldfinch (Carduelis tristis), and the Lesser Goldfinch (Carduelis psaltria). They like their sunflower and nyjer seeds and they are quite vocal in their complaints when I let the feeders go too low.

I thought the gray bird in the picture below was a mockingbird from a distance, but some of my facebook experts suggest that it is a Western Kingbird (Tyrannus verticalis). I am open to being corrected in this identification.

True to the season, here are two doves, but they aren't turtle doves. I was told (and agree) that these are Eurasian Collared Doves (Streptopelia decaocto). It is an relatively recent invasive species that I have constantly mistaken for Mourning Doves.

On a brief foray along the Tuolumne River near La Grange we found an American Kestrel (Falco sparverius) watching for a meal from a telephone pole.

For ten years I've been trying to catch a photo of a Yellow-billed Magpie (Pica nuttalli), a species unique to California (it is a cousin to the Black-billed Magpie found in much of the rest of the country). They have been very shy when I come around with a camera, but one hung around for a moment before flying away the other day. They've been decimated by the West Nile Virus.

I am familiar with the story of how European Starlings (Sturnus vulgaris) arrived in America to become a pest (it was a Shakespeare lover of all people), but I had never noticed them around my neighborhood until I started walking a few weeks ago.

The Killdeer (Charadrius vociferus) is a widespread species found all over the Americas, but it holds kind of a special place in our valley. We chose it to be part of our banners and symbols for the new Science Community Center at Modesto Junior College. As if to play the part, a Killdeer set up a nest on the vacant lot north of our building that will eventually become our Outdoor Nature Laboratory. I often hear them when I walk around the campus.

 There must have been a dozen of them running about the cow pasture a few blocks from my house.

The biggest surprise in my recent walks was the drumming of a woodpecker. I've never noticed any near my house, but walking under a telephone I heard one pecking away.

A bit of research suggested that it might be a Nuttall's Woodpecker (Picoides nuttallii). It's the second kind I've seen in the region so far (the other is the Acorn Woodpecker, farther up in the mountains).

The small bird wandering in the grassland appears to me to be an American Pipit (Anthus rubescens), but I await your confirmation. They hide well, so I've never noticed them before.

The other of many pleasant surprises has been the spotting of some Western Bluebirds (Sialia mexicana) in the trees around the cow pasture. I don't think they've visited our bird feeders.

The pictures I took the other day show a brightly colored male (above), and a slightly more drab female (below). I'd like to see more of them!

I've enjoyed paying more attention to our local bird life, and look forward to adding more of them during my travels. Once again, have a wonderful Christmas and restful holiday!

A Convergence of Wonders, Day 10: Exploring a Real Hot Spot

It was day 10 of our field studies journey through the Pacific Northwest and Northern Rocky Mountains. We had finally arrived at one of the flagship destinations for our trip: Yellowstone National Park! One of the crown jewels of our national park system, home of Old Faithful...we set aside two days to explore the park, and I did something slightly devious to my students. I spent the entire day looking at "not geysers"!

Frankly, I'm not sure any of the students noticed the distinction. That's the thing about Yellowstone; it is so full of wonders and curiosities that it would be a unique landscape to explore even if there were no geysers to be seen at all. We spent our day exploring the northern loop of the park, from Canyon Village and the Grand Canyon of the Yellowstone to Mt. Washburn and then to Mammoth Hot Springs. We stopped in at Norris Geyser Basin at the end of the day, but were distracted by a wolf.

It's funny about furry charismatic animals; they seem to trump the attention of everyone, especially geology students. Our first stop of the day had nothing to do with geology at all, it was to photograph an elk. One cannot travel fast in Yellowstone National Park, because there are constant traffic jams caused by tourons (tourist morons, including ourselves...) looking at bison, elk, bear, moose, beaver, or wolf. I was immune to the effect. I took only ten pictures of this particular elk...

We explored several overlooks at the Grand Canyon of the Yellowstone and Lower Yellowstone Falls. The colorful walls of the canyon are composed of weathered rhyolite just over 500,000 years old. This canyon has been cut very rapidly! 

Standing at the brink of the 308-foot-high Lower Fall of the Yellowstone, one can feel the powerful surge of the water as it disappears over edge. It's not hard to believe that such a deep canyon could be carved by a river like this.

The most astounding story to be learned at Yellowstone was never envisioned by those who established Yellowstone as our first national park in 1873 (Yosemite was set aside nine years earlier, but as a state park). We drove to the high ridge near Dunraven Pass and Mt. Washburn to have a look around.

There is a fable about several blind men who were touching an elephant and disagreeing about its nature, whether it was like a rope (the tail), a snake (the trunk), or a tree (the leg). Yellowstone's most striking feature was so big that it was decades before geologists recognized it for what it was: a vast caldera, the site of three of the largest volcanic eruptions to ever hit the North American Continent in recent geologic time (2.1 million, 1.3 million, and 640,000 years before present).

How big is the caldera? The snowcapped mountain in the distance in the picture below is Mt. Sheridan. We were standing on the side of  Mt. Washburn; there is a forty mile gap between the two. The mountain ridge that connected the two peaks sank into the caldera during a single massive eruption that put 600 cubic miles of ash into the atmosphere. The ash spread for thousands of miles. A repeat eruption would be devastating to civilization (despite what the television tells you, such eruptions are not imminent, nor are they overdue; we would see signs of caldera unrest dozens, if not hundreds of years beforehand). The source of these eruptions is thought to be a mantle hot spot, although there are several alternate interpretations.

Volcanism has been influencing events in the Yellowstone region for a long time. In early Cenozoic time, around 50 million years ago, the region was rocked by numerous eruptions that produced volcanic mudflows (lahars) that overwhelmed forests of sequoia/redwood trees (You thought they were found only in California didn't you? They were once much more widespread). Each time a forest was destroyed and buried, a new forest would grow in the sediments. That forest was destroyed in turn, and over time dozens of layers containing petrified logs accumulated. These forests are generally hard to access by road or trail, but one solitary upright trunk can be seen in the north part of the park. There used to be three here, but souvenir collectors carted off the others, which explains the prison in which the trunk resides.

We moved on down to Mammoth Hot Springs (with a few bear diversions), and took a look at the strange edifice of calcium carbonate. Most of the hot springs and geysers of Yellowstone do not produce massive mineral deposits, but they happened here, outside the boundaries of the caldera. Most of the water emerging from geothermal features in the park is charged with silica, but at Mammoth, the water has passed along faults that traversed Paleozoic limestones. The acidic waters dissolved the calcite making up the limestone, and when the waters emerged here, the calcite came out of solution.

The hot springs are constantly growing and changing location, so the deposits never look quite the same. Heat-tolerant bacteria provide a splash of color to the otherwise snow-white rock.

Spelunkers (cavers) will recognize many of the deposits, as they are similar to flowstone features found in many limestone caverns, especially the rimstone pools seen in the pictures below. Exploring Mammoth Hot Springs is kind of like exploring an inside-out cavern...

 The rimstone pools were especially photogenic...

There were several killdeers strolling across the pools...

We drove on in the late afternoon to Norris Geyser Basin, but I didn't get any pictures. We were distracted by the whole charismatic mammal thing anyway, the subject this time being a Canis lupus enjoying a meal in a meadow north of Norris.

You can see the whole wolf drama in this post.

We were done with another day...tomorrow would include the famous geysers (maybe), and Grand Teton National Park.

I've been posting regularly for the last ten days, but I am hitting the road again tomorrow, so the next few posts will be at unpredictable intervals, as web access will be tricky. Take care, all!