The Prairies of California: the Most Extraordinary Landscape (and Ecosystem) in California

The Tuolumne River on the east side of the Great Valley

I admit this statement is a hard sell, especially among those who live here, but hear me out: the Great Valley prairie is the most extraordinary landscape and ecosystem in California. 

The Great Valley prairie remnant east of Modesto

"But", they will say, "the valley is boring. It is just one long flat plain full of farms, feedlots, oil derricks, and urban hellscapes. It's dusty and the air is bad. And there is nothing to do." And from their point of view, their statement is valid. But that's not the part that I am talking about. I'm talking about the valley that once was, and more importantly, the 5% of the valley that is not given over to agriculture and urban development. It is that small bit that teaches us what once was. 

I was thinking a lot about the original valley today.

Prairie and wetlands at the San Luis National Wildlife Refuge south of Turlock

The occasion was World Migratory Bird Day, Global Bird Weekend, and eBird's October Big Day. The purpose of the day is to gain a one-day snapshot of the world of birds, and birdwatchers all over the world contributed observations. For myself, I decided I wanted to capture as much of the primeval Great Valley prairie as I could, so I selected three habitats for the day: the valley wetlands and marshes, the riparian environment, and the dryland prairies that once filled the spaces between the rivers and wetlands. In the end Mrs. Geotripper and I explored the Merced National Wildlife Refuge and the San Luis National Wildlife Refuge, and in the afternoon I walked the Tuolumne River Parkway Trail (as I often do). As the sun began to set I took a drive through the prairies between the Tuolumne and Stanislaus Rivers east of Modesto. In all we saw nearly 60 species of birds.

One of the most extraordinary facts about the prairie lands of California is that they ever existed at all. The Great Valley is 400 miles long and 30-40 miles wide, and with the exception of a single volcanic center at Sutter Buttes, is as flat as any place on Earth. The entire American West is characterized by rugged mountainous topography, including the Coast Ranges and Sierra Nevada of California between which the Great Valley is sandwiched. Such a large mostly flat region is akin to finding a serene quiet lake surface in the midst of an intense hurricane.

The origin of the Great Valley lies in the violent tectonics of the subduction zone that existed off the coast of California for at least 200 million years. A region of oceanic crust was being driving beneath the western edge of the North American continent, forming a trench and a deformed mass of sediment called an accretionary wedge. Parts of the accretionary wedge were buoyed upwards to become the core of California's Coast Ranges.

As the slab of ocean crust sank into the Earth's mantle, portions of the plate melted and formed vast plutons of magma that melted their way through the overlying continental crust, forming an extensive volcanic chain called a magmatic arc. The deeper parts of the magmatic arc eventually cooled to become the granitic rocks of the Sierra Nevada.

Between the geologically violent wedge and arc though was a shallow sea that simply collected sediments washed off the land. This sedimentary trough is known as a forearc basin. As the sediments accumulated, they pressed the crust downwards, providing room for additional sediments. Eventually these silt and sand layers reached a thickness of 25,000 feet or more. These sediments became the floor of the Great Valley.

Source: National Park Service

The valley was below sea level for most of its first 140 million years, but in the last four or five million years the floor of the valley was lifted slightly above sea level to become the plain it is today. It is dry in large part because the adjacent Coast Ranges act as a barrier to incoming storms from the Pacific Ocean. It is literally a desert in the southern portions from Fresno to Bakersfield, but the dry plain is crossed by numerous rivers flowing out of the Sierra Nevada.

In antiquity the valley was a vast prairie, a grassland stretching 400 miles from what is now Bakersfield to Redding. The drylands were broken up by a system of rivers, marshes and wetlands that supported groves of oak, cottonwood, and sycamore and vast thickets of willows and shrubs. These plants supported a rich fauna.

Until roughly 12,000 years ago, the prairies were populated by millions of grazing animals including horses, camels, deer, elk, bison, and even elephant species like mammoths and mastodons. This megafauna was preyed upon by a terrifying roster of predators including saber-tooth cats, 
lions, cheetahs, dire wolves, and bears, including the California Grizzly and the even larger short-faced bear. The cause of the extinction of most of these species is still debated, but the prime suspects are climate change and overhunting by newly-arrived humans. A minority view argues for an asteroid impact that primarily affected North America.

Sandhill Crane and Great Egret at the Merced National Wildlife Refuge

In the aftermath of the extinctions, the valley still supported a robust ecosystem. The mild winters provided shelter for millions of migratory birds, and the grasslands were grazed by elk, deer, and antelope. Predators included wolves, coyotes, foxes, mountain lions, and bears. The Tule Elk were thought to have been hunted to extinction in the years after the Gold Rush, but a small remnant of the species survived on a single ranch at the south end of the valley. The California grizzly and wolves were eliminated in the early 1900s. 

Tule Elk bull at the San Luis National Wildlife Refuge. We didn't see any today so I borrowed a shot I took in 2016

Today the remaining original prairie and wetlands environments are present due to sheer luck, and from concerted efforts by many environmental organizations and government agencies. A series of national wildlife refuges have been established like a string of pearls up and down the valley to provide habitat for the millions of migrating cranes, geese, swans and other species.

The White-faced Ibis is a tropical species that looks almost black until the sun shines on the iridescent feathers. The white face appears in the breeding season.

Some grass prairies are preserved in state parks and national monuments (most notably Carrizo Plains National Monument). But most persist because they are on cattle ranch property. These private lands are threatened by the rapid expansion of almond groves into the foothills. In my county alone, tens of thousands of acres have been planted, with no secure irrigation sources for the thirsty trees. I'm pretty sure they'll be abandoned within a decade or so as the groundwater they are using dries up.

Dry Creek, shown here, has earned its name this year, although it is capable of serious flooding in wet years. An invading and misguided almond orchard can be seen at upper right.

The riparian habitats have their own problems. The river woodlands are among the least-affected environments as attempts to develop them as farmlands tended to fail because of repeated flooding. Still, much damage was done in the attempt, and current efforts are directed at replanting native species in floodplains that have reverted to government or conservancy ownership.

The Tuolumne River near the Sierra Nevada foothills.

It is the rivers themselves that face the biggest challenges. There is no more contentious issue in the Great Valley than water use and distribution, especially in severe drought years. All of the major rivers are dammed and strictly controlled except for the occasional exceptional flood. The Tuolumne has been kept at a minimal flow, enough to maintain a string of river water into the delta. The slow-moving water is subject to warming to a dangerous level for river species, and the expansion of invasive species like river hyacinth. Through it all the river is a beautiful walk at all times of the year.

Sandhill Cranes at the San Luis National Wildlife Refuge

It was a serene day, but it was also the calm before the storm. The migratory birds are beginning to arrive in greater numbers, and soon these pools will be filled with Snow and Ross's Geese, Tundra Swans, and Aleutian Cackling Geese. There is nothing quite like seeing a flock of 10,000 geese take off all at once. It becomes so easy to imagine what once was in this most extraordinary place.

Pictorial Celebration of Wetlands Day: the Great Valley of California

Sunset at the San Joaquin River NWR near the Beckwith Road Viewing Platform

Before going any farther, please go over to Siera Nystrom's wonderful blog Natural History Journal for this excellent piece on World Wetlands Day, which is on February 2. She's delivered an excellent review about the meaning and value of wetlands to all of us.

Really! Go read it first!....okay, are you back now?

Snow and Ross's Geese taking flight at the San Joaquin River NWR

I wanted to add my own celebration of wetlands here at Geotripper because I happen to live adjacent to some of the most important wetlands in the world, and those wetlands are under attack. The Great Valley of California is to many a featureless plain 400 miles long that is covered by millions of acres of agricultural lands. That's true, but that reality obscures an even more important reality: the Great Valley is a critical and priceless link in the Pacific Migratory Flyway, and as such it provides shelter and food to millions upon millions of bird species who travel the region with the seasons.

Snow and Ross's Geese at the San Joaquin River NWR

95% of the original prairies and wetlands have been converted to agricultural development, but the 5% that remains includes critical habitat for these birds, preserved as a string of wildlife refuges and parks along the length of the valley. It's not enough, but over time as some farmlands are retired, the acreage for the birds slowly increases. There are a number of National Wildlife Refuges that I visit on a regular basis. The first, shown in the first four pictures above, is the San Joaquin River National Wildlife Refuge.

Aleutian Cackling Geese and Snow Geese at the Beckwith Road Viewing Platform

The refuge has two principle areas where observations and exploration are possible: a viewing platform at the western end of Beckwith Road about 7 miles west of the town of Modesto, and the Pelican Trail, a 4.5 mile long loop trail along the San Joaquin River south of Vernalis and Highway 132. The principle attraction during the winter are the huge flocks of Aleutian Cackling Geese (much or most of the world's population of the species), and tens of thousands of Sandhill Cranes, Snow Geese, Ross's Geese, and Greater White-fronted Geese. The diverse environments within the refuges support nearly 200 species of birds along with the mammals, reptiles, fish, and amphibians that form the complex web of life along the rivers and marshes.

Merced NWR at Sunset

The other main complex is the San Luis National Wildlife Refuge, which has several units along the San Joaquin River south of Turlock. The refuge includes the main San Luis refuge and Tule Elk Preserve, along with Bear Creek Unit and the Merced National Wildlife Refuge.

Sandhill Cranes at the Merced NWR

The Merced Unit is home to well over 200 species of birds, which in winter includes tens of thousands of Sandhill Cranes and Snow/Ross's Geese. There is a six mile auto tour that allows visitors to see vast numbers of birds in seasonal and permanent ponds. We were there on Friday for a few hours and recorded nearly fifty bird species, including my first decent pictures of a Common Yellowthroat (not so common for me!).

Common Yellowthroat at the Merced NWR

Along most of the tour visitors remain in their vehicles, which thus act as a sort of blind. Because of this, birds often remain close to the road and it is possible to get some extreme close-ups of some very colorful birds like those seen below. There are also three short hiking trails where one can stretch legs and get a chance to hear the quieter and more well-hidden bird species.

Gadwall at the Merced NWR

The main part of the San Luis NWR has two major auto-tours and an extensive new visitor center, along with a variety of hiking trails. A major attraction is the Tule Elk compound, a square mile area where the elk are free to roam about. Visitors can follow a road that completely surrounds the compound.

Tule Elk at the San Luis NWR

The Tule Elk have a tortured history in California. They are a distinct subspecies of the elk clan, native to the state. They were one of the most abundant large grazers on the California prairie prior to the arrival of European colonists, with numbers estimated at about 500,000. They were hunted literally to oblivion, and when hunting of the elk was outlawed in 1873 they were thought to be already extinct. A small number, either two or four according to the story, were found on Henry Miller's ranch in the south San Joaquin Valley, and Miller undertook to protect them. They hovered near extinction for the next several decades, but preserves have been established around the state and the herd has reached a population of more than 5,000 individuals. They are still threatened by lack of  genetic diversity, given that they are all descended from a single pair or two.

American Wigeon

The second auto-tour at the San Luis NWR, the Waterfowl Route, is a fascinating journey through a land that closely resembles the primeval appearance of the Great Valley, with stretches that include open prairie, marshes, and riparian (river) habitats. We see all manner of raptors such as Northern Harriers, White-tailed Kites, Red-tailed Hawks, and Great Horned Owls. There are thousands of geese, swans, ducks and coots in the ponds and marshes, and we've seen Muskrats, River Otters, Raccoons, Deer, and Coyotes.

Ruddy Duck at the Merced NWR

There is a less traveled part of the San Luis NWR called the Bear Creek Unit, accessed off of Highway 165 south of Turlock and Hilmar. There is a short two-mile auto-tour and two trails, but birders have only made about 150 reports there compared to over 1,000 at the Waterfowl Route, and more than 2,000 at the Merced NWR.

Green-winged Teal at the Merced NWR

The ponds are often dry and the birding can be sparse, but when the ponds are full there are thousands of Red-winged Blackbirds, and it is the only reliable spot where I've found Yellow-headed Blackbirds. These birds are incredibly beautiful to photograph, but their call is not nearly so attractive. To me it sounds a lot like scraping metal!

Yellow-headed Blackbird at the Bear Creek Unit of the San Luis NWR

There are other areas throughout our region that I have not had a chance to explore yet, including the Great Valley Grasslands State Park, the Kesterson Unit of the San Luis NWR, the Los Banos Wildlife Management Area, and the Merced Vernal Pools and Grasslands Reserve. Life is so short!

American Avocet at the Merced NWR

Unfortunately, in the midst of a celebration of the diversity of life and an appreciation for the beauty to be found in our wetlands, there is a tragic reality: our government is in the hands of those who see protection of wetlands as an impediment to their quest for profits, and that government is actively seeking to destroy our precious remaining wetlands in the name of unconstrained development. They literally want to poison our water for the sake of monetary gain.

Great Horned Owl at the Merced NWR

You can read some of the details in this article, but here is the main takeaway...

This sickening gift to polluters will allow wetlands, streams and rivers across a vast stretch of America to be obliterated with pollution," ... "People and wildlife need clean water to thrive. Destroying half of our nation's streams and wetlands will be one of Trump's ugliest legacies. We'll absolutely be fighting it in court.

After so much that has been lost, especially here in California, and here in my home in the Great Valley, I am sickened at heart that men so craven have been allowed to destroy so much that is good. I hope you can appreciate the incredible legacy we have in our valley, and that you might become part of the fight to preserve the small parts that remain.

Sunset at the Bear Creek Unit of the San Luis NWR

Good-bye to 2018: 12 Months of the Joy of Geology

Mesa Arch in Canyonlands National Park

It's been a year. There are lots of ways of looking at the events of 2018 and so many of them are tragic and unjust. But there is always hope as well. There are still the beautiful places of the Earth, and always a chance to seek them out, no matter where you are. That's the joy of being a geologist and a teacher. Or being anyone with a curiosity about our planet. What follows are twelve months of exploring our planet from my base in California's Great Valley.

Merced National Wildlife Refuge, south of the city of Merced.

Where does one go in January? So much of the countryside is covered in snow, but California is kind of special in that regard. We get to visit the snow if we want and then we can go home to our valleys and coastlines. The migrant birds know all about this. Millions of geese and other species spend their summers in the Arctic, but when the snows come they fly south and spend the winter in a series of wetlands and prairies that have been preserved in places like the Great Valley. Our destination in January was the Merced National Wildlife Refuge. There were thousands of Sandhill Cranes, Snow Geese, Ross's Geese, and multitudes of ducks. It is an overwhelming experience to stand at the edge of the wetlands and imagine this valley hundreds of years ago before agricultural development took over 95% of the landscape.

Zabriskie Point and Manly Beacon in Death Valley National Park

The most satisfying aspect of a teaching position in geology is the chance I have to share the incredible planet with my students in my classroom of course, but also in the field. In February our intrepid crew headed out to Death Valley National Park in the Basin and Range Province of eastern California. The valley is a vast fault graben with 11,000 foot peaks next to valley floors below sea level. It is the hottest place in the world and the driest place in North America, yet 20,000 years ago it contained a 100-mile long freshwater lake and grassy savannas with horses, camels, and mammoths. Some of the fish who inhabited the lake still survive today in isolated spring-fed ponds.

Natural Bridge in Death Valley National Park

Death Valley is recognized as the premier geology park in the national park system, containing rocks as old as 1.7 billion years, and including layers and intrusions from every period in Earth history ever since.

We survived a phenomenal windstorm on the last night of our trip. I hate to say I littered in a national park, but somewhere out on the dunes there is a tarp that blew away from under my tent in the night.

The Ghirardelli Store in Hornitos within the Sierra Nevada Mother Lode

Our field studies in March were closer to home. We journeyed through the southern Mother Lode of the Sierra Nevada. We saw ghost towns, old mines, and the quartz veins that were the source of the ores of the California Gold Rush in 1848. The ruins in the picture above are the Ghirardelli Store in Hornitos. Before he made chocolate in San Francisco, the man sold supplies to the miners in the Mother Lode.

Yosemite Falls in Yosemite Valley

In April, Yosemite National Park took center stage, as we took two field studies trips there. One of them was the morning after an epic flood that closed the park for a day or two. When we got there, the Merced River was still at flood stage and the waterfalls were booming.

Mt. Rainier in Washington

In May, family matters found us on a plane out of Seattle, Washington. We left for home in the early evening while Mt. Rainier was capturing the last rays of the sun. As you may have read in the last post, Rainier (14,411 feet) is the tallest volcano in the Cascade Range, and has more glacial ice than any mountain in the Pacific Northwest. The potential of eruptions happening under the ice makes Rainier one of the most dangerous volcanoes on the planet. Lahars (volcanic mudflows) could overwhelm some of the cities of the Puget Sound.

Horseshoe Bend on the Colorado downstream of Lake Powell and Glen Canyon Dam

One of the greatest adventures one could ever experience is an in-depth exploration of the Colorado Plateau. It is a showcase of geology with a treasure trove of national parks and monuments. In June, our intrepid crew headed out to plateau country where we explored Grand Canyon, Zion, Bryce Canyon, Black Canyon of the Gunnison, Mesa Verde, Arches, Canyonlands, Capitol Reef and Great Basin National Parks. The region is so extraordinary that a place like Horseshoe Bend on the Colorado River isn't even in a national park or monument.

House on Fire Ruin in Bear's Ears National Monument

One of the great crimes of the present administration in Washington D.C. was the attack upon the Bear's Ears National Monument. Even though the law didn't allow it, the park was reduced in size to 15% of what it had been before. And for the sole purpose of money, i.e. oil drilling and uranium mining. I hope the courts do the right thing this year.

Hurricane Ridge in Olympic National Park

In July Mrs. Geotripper and I escaped the heat and dust of the Great Valley and headed north along the coast, eventually reaching Olympic National Park in Washington. Hurricane Ridge is one of the most stunning viewpoints in America. The views take in the alpine peaks glaciers of Mt. Olympus, the temperate rainforests of the valleys, and the coastlines around Port Angeles. The mountains are composed of oceanic sediments and seafloor crust pushed upwards by the motions of the Cascadia Subduction Zone.

We stayed close to home in August, but almost every morning found me walking the Parkway Trail along the Tuolumne River where it flows from the Sierra Nevada foothills onto the floor of the Great Valley. Birders (including me) discovered 115 species on this trail over the course of the year.

Valentine Cave in Lava Beds National Monument

The resumption of classes in August and September found me and my students on the road again. We explored the Cascades Volcanoes, including Mt. Shasta, Lassen Peak, Medicine Lake Highland and Lava Beds National Monument. Lava Beds has miles of lava tubes, one of the greatest concentrations in the world.

In October we went underground again with an exploration of Black Chasm Cavern. The cave has been carefully managed so that visitors can see cave decorations that are absolutely pristine. The cave has thousands of fragile speleothems called helictites. I call them stalactites on acid...

November was the lost month. The horrific fire in Paradise caused air quality to suffer throughout the state and the school shut down for a week and a half. It's the first time this has happened, and our scheduled field trip to Pinnacles National Park was postponed to the beginning of December. We went underground again, in yet another kind of cave. It wasn't limestone or marble, and it was a lava tube even though the Pinnacles are volcanic. It's a talus cave, one caused by giant boulders falling into and covering a narrow canyon. Hikers are in near total darkness for upwards of a quarter mile.

December arrived and along with it came the holidays. We have family all along the coast from California to Washington, so Christmas for us was a very long road trip. On our last night we stayed near Mt. Shasta in Northern California. The sunset provided beautiful lenticular clouds around the summit of the second and third highest volcanoes in the Cascades (you'll have to check out the last post to learn about that one).

And that was the story of my year and that of my students and Mrs. Geotripper. We saw a lot of incredible things, and my whole purpose in describing these places is to encourage you to explore them for yourselves. I know that this is impossible for many, which is quite literally why I write this blog. But if you can make time and get away, seek out the wild places where you live. If your local college offers field studies courses, consider getting back into school for some personal enrichment. I guarantee you won't regret it.

If you live in the vicinity of Modesto, the Modesto Junior College Geology Department will be offering a great line-up of field studies courses. We'll explore Death Valley again in February, the Southern Mother Lode in March, and Yosemite Valley in April. In September we'll head out to the Eastern Sierra Nevada and Owens Valley. In October we'll travel through the Mother Lode, and in November we'll be back to Pinnacles National Park.

But our premier trip with be on June 26-July 10 when we head to British Columbia and the Pacific Northwest. We'll be exploring Olympic and North Cascades National Parks, Vancouver Island, and the Coastal Mountain Ranges around Whistler and Pemberton. It will be a memorable experience. If you are interested, keep an eye on this blog, follow our Facebook page at https://www.facebook.com/groups/1920712791360611/, or the class web page (soon to be updated) at http://hayesg.faculty.mjc.edu/GeologyPacificNorthwest.html.

See you on the road!

Seeking the Savanna instead of Seas: "Saturday Night Live" and Geology??

Historical geology is a real head trip (remember that term?). Stick geologists in the desert against a cliff like the one above, and they will make a few observations, pick up a few stones (and/or fossils), and in their mind's eye, they will be exploring a long-ago prairie that would have looked much like the one in the picture below (a bit of the rarest ecosystem in California, the prairie at Merced National Wildlife Refuge).

There would be differences of course. This current-day prairie is populated by a diverse group of birds and small mammals like ground squirrels and rabbits. But it lacks some of the components of a healthy modern wild prairie, mainly the larger grazing animals like deer, antelope, and bison, and the large carnivores that would prey on them. Coyotes and foxes still inhabit the region, and cattle or sheep are sometimes brought onto the prairie to help maintain the quality of the grasslands. But the larger canines and cats, i.e. the wolves and the lions, are long gone, as are the bears.

We were on the first full day of our exploration of Death Valley National Park. We weren't there yet, because we had a hundred miles of Mojave Desert to cross before we reached the park. Along the way we made a stop at one of California's most spectacular state parks, Red Rock Canyon (not to be confused with the Red Rock Canyon National Conservation Area outside of Las Vegas). Red Rock Canyon is on Highway 14 between the town of Mojave and Lone Pine, southeast of the Sierra Nevada. The place will look familiar to many, as the striking red and white cliffs have formed the backdrop to dozens if not hundreds of Hollywood movies (including some the opening scenes of the original Jurassic Park).

The plain hills to the south of our parking area (in the picture above) are composed of Paleozoic and older metamorphic rocks that have been displaced and uplifted along the Garlock Fault just south of the park. The rocks have been moved some forty miles from their original location by the left lateral movements of the fault zone. They have their own fascinating story, but what catches the eye are the much more colorful sedimentary layers that were deposited on the eroded surface of the metamorphic rocks between about 8 and 12.5 million years ago, a time period called the Miocene epoch.

For many of our students, this is the first real-world example of the basic principles of stratigraphy. We spent a few minutes talking about the birth of the science of geology in the observations of Nicolas Steno (superposition, lateral continuity, and original horizontality), and James Hutton (uniformitarianism). Then I unleashed them onto the rock exposures so they could evaluate the origins of the rocks and the sequence of events that produced the spectacular cliffs in front of us.

Understanding the changes of a prairie ecosystem through time is as easy as understanding "Saturday Night Live" (which for a fact might not be that easy). For more than forty years the underlying structure of the show has remained much the same; there's a guest host, there is a cold open ("It's Saturday Night!"), there are skits, there is the weekend news, there are fake ads, there are musical numbers. But cast is constantly in flux. There have been many people over the years who have filled in the niches: those who could mimic political figures, those who could act as the "straight man/woman", those who could sing. Sometimes the actors were so unmemorable that they disappeared without a trace after a few weeks or months. Others were successful, and remained for years. Others went on to greater things, like Hollywood movies. And that's how the prairie savanna has worked over the years.

Once our students have looked closely at the rocks, they've identified that there are fine layers representing deposition in lakes, other layers that formed on floodplains or alluvial fans. The terrestrial origin of many of the layers is supported by the bright red color, formed as iron in the rocks oxidized into natural rust. What we don't have time for (or permission for that matter) is a search for fossils, because it is the fossils that tell the fullest story of these rocks. Are these fossils the John Belushi-Dan Akroyd period of the grasslands? Or the Joe Piscopo-Eddie Murphy period? Or Kate McKinnon?

Grasses emerged as a dominant plant species in the middle of the Cenozoic period around 30-35 million years ago. The low-lying plants had a novel method of survival: instead of broad leaves easily chewed by forest-dwelling animals, the blades of grass incorporated silica into their structure, and the hard silica would soon destroy the teeth of most animals that tried to subsist on it. A general warming and drying of the world climate led to the expansion of the grasses at the expense of woodlands and tropical rainforests. Animals either adapted to the new conditions or went extinct. The early part of the Oligocene and early Miocene saw many changing species, especially in the horse clan. The ancestors of the horses were small browsers in the forests. As they adapted to the open grasslands, they became larger, and their feet went from three or four toes to hooves, which gave them great speed to escape predators. Their teeth evolved to grow throughout life, allowing them to survive nicely while grazing the grasslands.

The fossil-bearing rocks at Red Canyon are called the Dove Spring Formation (formerly the Ricardo Formation). The cast of characters are familiar in the sense that they fill the roles of many species on the prairies and wetlands today, but there were some unfamiliar characters as well. More than a hundred species of plants and animals have been found, making this one of the richest and most diverse fossil assemblages in the American West. They include the smallest mammalian members of the ecosystem such as mice, ground squirrels, rabbits and even a pika. The larger grazers were represented by ten (yes, ten) species of horse (compared to the three existing in the present day), four camel species, and three species of antelope. There were the surprising ones, two rhinoceros species, and two elephant ancestors (gomphotherium). The carnivores are represented by eight species of canine ancestors (some are called the "bone-crushing dogs"), and three species of felids (cats), including an early saber-tooth. There is a fair candidate for the ancestor of bears and dogs called a "bear dog" (Amphicyon). For a complete listing of the fossils found at Red Rock, check out this technical report from 2009.

So our investigation of an ancient savanna prairie revealed some of the early players in the drama that has played out across North America over millions of years. Some of the players (genera) were diverse and widespread but ultimately died out in North America (the horses and camels, rhinos and elephants). Other lineages survived, including the deer, the pronghorns, and predators like the wolves, coyotes, mountain lions, and foxes. The bears still lurk nearby in the mountains and would no doubt reoccupy the grasslands if the farms disappeared. Like "Saturday Night Live", the show continues and hasn't suffered cancellation, but a great many changes have taken place. The prairies of 12 million years ago can still be found in California today, but with a new cast and a different look.