Restoring the #ColoradoRiver: Bringing New Life to a Stressed River — Yale 360 #COriver #aridification

Colorado River Delta

From Yale 360 (Jim Robbins). Here’s an excerpt click through for the photos and to read the whole article:

The Colorado River has been dammed, diverted, and slowed by reservoirs, strangling the life out of a once-thriving ecosystem. But in the U.S. and Mexico, efforts are underway to revive sections of the river and restore vital riparian habitat for native plants, fish, and wildlife. Fifth in a series.

From the air, the last gasp of the Colorado River is sudden and dramatic. The pale green river flows smack into the Morelos Dam on the U.S.-Mexico border, and virtually all of it is immediately diverted into a large irrigation canal that waters a mosaic of hundreds of fields — alfalfa, asparagus, lettuce, and other vegetables, their vivid green color clashing against the sere desert. The slender thread of water that remains in the Colorado’s channel continues to flow south, but is soon swallowed up by a sea of sand, far short of its delta, which lies 100 miles farther on.

The Colorado River once surged through the delta during high flows, carrying so much water at times that shallow draft steamboats chugged hundreds of miles up the river into the U.S. with loads of freight. The water in the delta nourished a vast fertile landscape, a fitting end to a river known as the Nile of North America.

“The river was everywhere and nowhere,” the naturalist Aldo Leopold wrote during a 1922 canoe trip to the delta, describing the waterway as it ebbed, flowed, braided, and stalled into pools, nourishing a rich and diverse ecosystem of “a hundred green lagoons,” a “milk and honey wilderness” with thick stands of cottonwoods and willows that provided habitat for hundreds of species of birds. The delta’s marshes, mudflats, and white sand beaches were home to clapper rails, bitterns, mallards, teal, and clouds of egrets.

Bobcats, puma, deer, and wild boar wandered the delta’s forests. Leopold was searching for the jaguar that roamed there, but didn’t see any…

Morelos Dam. Photo credit American Rivers.

As a natural river, before it was dammed, the Colorado was a massive, dynamic waterway. It flowed from elevations above 14,000 feet in the Colorado Rockies, then dropped to sea level, which meant that it moved at high water with tremendous force, liquid sandpaper carving out red rock canyons. It flooded the desert plains, carving new channels and braids with every inundation. When it receded, it left behind a mosaic of fecund marshes, wetlands, and ponds.

In its natural state, the Colorado had more extreme flows than any river in the U.S., ranging from lows of 2,500 cubic feet per second in the winter to 100,000 cubic feet per second in the summer. In 1884, an all-time historical peak flow reached 384,000 cubic feet per second in Arizona.

But extreme flows are too capricious to support a civilization, so over the past century or so humans have built a network of expensive dams and reservoirs, pipelines, canals, flumes, and aqueducts to tame and divert the flow. Yet these projects also strangled the life out of a once-thriving ecosystem. By design, the river will never again function as a free-flowing stream.

Now, however, experts and environmentalists are rethinking this technological marvel of a river, and looking at ways a natural Colorado can flourish — to some degree, and in some places — with the permission of the engineers. One of those places is in the delta.

The water that flowed in the once-lush delta has been replaced by sand, and the cottonwoods and willows have surrendered their turf to widespread invasive salt cedar and arrowweed. Without the river and its load of nutrients, marine productivity in the Gulf of California — where the Colorado River once ended — has fallen by up to 95 percent. But despite the dismal forecast for the future of water on the Colorado, some conservationists are hoping to return at least a portion of the delta to its former glory.

Point 24 in the Colorado River Delta, September 12, 2016. Photo credit The Nature Conservancy.

“We are trying to restore a network of sites that creates a functional ecosystem,” said Francisco Zamora, who manages the project for the Sonoran Institute. “We’ve acquired water rights, but use them for habitat instead of cotton or wheat.”

The delta is one of a disconnected series of restoration projects that government agencies, local groups, and environmental organizations are undertaking along the Colorado. Numerous efforts are focused on tributaries to the main stem of the river, seeking to enhance resiliency by increasing the flow of water and protecting and restoring riparian habitat for fish and other wildlife.

For example, a coalition of groups — including state agencies, nonprofits, and the Arizona cities of Buckeye and Agua Fria — have been removing invasive salt cedar, planting native species, and building levees to reclaim a 17-mile stretch of the Gila River. Invasive salt cedars are a region-wide problem on the lower Colorado, with a single tree sucking up 300 gallons a day. The invasive forest on this stretch of the river uses enough water to serve 200,000 households.

In the upper basin, meanwhile, a number of groups and local landowners are working to restore a 15-mile-long floodplain with globally significant biodiversity on a narrow section of the Yampa River, another Colorado tributary. Called Morgan Bottom, the section has been damaged by deforestation and poor agricultural practices, threatening bald eagles and greater sand hill cranes, as well as a rare riparian forest of narrowleaf cottonwood and red osier dogwood.

But there are limits to how natural the Colorado River can become, especially along the river’s main stem. “We should not kid ourselves that we are making it natural again,” said John Fleck, the director of the University of New Mexico’s water resources program and the author of a book about the restoration of the Colorado. “We are creating an intensively managed system to mimic some nature because we value it.”

Because of the Colorado’s extensive infrastructure, serious disruption of the river’s ecology is inevitable.

Indeed, some of the remaining naturalness on the Colorado is, paradoxically, because of the human-made system. “The geography of the Colorado gives it hope because L.A. and southern California, which everybody loves to hate, guarantee that a lot of water stays in the system through the Grand Canyon,” says Jack Schmidt, a professor at Utah State University and a member of the Colorado River Research Group. “The best friend endangered fish ever had in the Colorado River Basin is that giant sucking sound” of California withdrawing water.

Widespread protection efforts are focused on native fish in the Colorado. The river once was home to an unusual number of endemic fish. But dams, irrigation, and the introduction of bullhead, carp, and catfish did them in. While the upper basin still has 14 native fish species, the lower basin, according to one study, “has the dubious distinction of being among the few major rivers of the world with an entirely introduced fish fauna.”

The Colorado pike minnow — something of a misnomer for a fish that historically grew to 6 feet in length and weighed up to 80 pounds — once swam through the entire system from Wyoming to Mexico. It is now listed as endangered, with two distinct populations remaining in the upper Colorado and the Green River.

The humpback chub lived in various canyon sections, and though once seriously endangered, it has fared better in recent years through transplantation efforts, growing from 2,000 to 3,000 fish to 11,000. Officials say it may soon be taken off the endangered list.

Beginnings. Photo: Brent Gardner-Smith/Aspen Journalism

Razorback suckers, once common, are now rare. The bonytail, a type of chub that is one of North America’s most endangered fish, no longer exists in the wild. A handful of these fish exist in hatcheries, and attempts are underway to restock them in the river throughout the basin.

Because of the Colorado’s extensive infrastructure, serious disruption of the river’s ecology is inevitable. Dams trap most of the river’s sediment in reservoirs, which means there is no material to rebuild beaches, sandbars, and important fish habitat downstream.

Dams also deprive the river downstream of nutrients, such as phosphorous and nitrogen, and stratify water temperatures. The native fish in the Colorado adapted to a wide range of temperatures, from cold to very warm. They also evolved to tolerate high flood flows along with extremely dry periods. Now, the water is cold in the summer for miles below the dams, and the humpback chub and other fish that had adapted to a range of water temperatures and flows suffer.

Something called hydro-peaking also has had serious impacts on the food web. Dams generate power according to demand. As people come home from work and switch on the stove, air conditioning, and lights, demand soars and dams release more water to produce power. “Prior to the construction of dams, there were almost no major daily changes in river levels,” said David Lytle, a professor of integrative biology at Oregon State University. When fluctuations in water levels occur, they “can interrupt the egg-laying practices of some species. It’s a serious problem.”

Insects lay their eggs just below the water level, and if levels drop rapidly it can dry them out. A recent study found that below the Hoover and Glen Canyon dams, there was a complete absence of stoneflies, mayflies, and other species — insects that are vital food for fish, bats, birds, and other creatures.

Because of the ecological effects of the Glen Canyon Dam, the Grand Canyon stretch of the Colorado is one of the least productive sections of river in the world. The Colorado here will always be highly unnatural, a novel, human-created ecosystem with some natural elements.

Today, there is a large and growing backlash against dams in America and elsewhere as the immense damages they have inflicted on rivers become manifest. Few dams, though, are as reviled as the Glen Canyon, which was built in 1963 and took 17 years to fill Lake Powell.

Before the Glen Canyon was dammed, those who saw it say it was not unlike the Grand Canyon, with towering walls of red, tan, and ochre. Early Native American sites were plentiful. Environmental activist Edward Abbey decried the dam, and in his novel the Monkey Wrench Gang fantasized about using houseboats packed with explosives to blow it up. In 1981, members of Earth First!, a radical environmental group with a connection to Abbey, rolled a black plastic “crack” down the face of the dam to symbolize its demise.

Changes in the northeastern reaches of Lake Powell are documented in this series of natural-color images taken by the Landsat series of satellites between 1999 and 2017. The Colorado River flows in from the east around Mile Crag Bend and is swallowed by the lake. At the west end of Narrow Canyon, the Dirty Devil River joins the lake from the north. (At normal water levels, both rivers are essentially part of the reservoir.) At the beginning of the series in 1999, water levels in Lake Powell were relatively high, and the water was a clear, dark blue. The sediment-filled Colorado River appeared green-brown. To see the complete series go to: earthobservatory.nasa.gov/WorldOfChange/LakePowell. Photos via NASA

Removing the dam was part of the reason the Glen Canyon Institute was formed, but activists have now dropped that idea, says Rich Ingebretsen, a Salt Lake City physician who founded the group. Today, he advocates draining Lake Powell to fill Lake Mead, which is downstream and where the need for water is by far the greatest. The “Fill Mead First” campaign would restore a free-running Colorado River to what was once Lake Powell.

“You’d get much of Glen Canyon back,” said Ingebretsen. “A free-flowing river through the Grand Canyon means you’d restore the river — riparian zones, animals that belong there, a beautiful canyon with arches and bridges and waterfalls. Much of that would come back very quickly.” There would also be increased water in the river, he says, because so much of the Colorado is now lost from Lake Powell; scientists estimate that the lake loses three times Nevada’s allotment of water because of evaporation. As levels in Lake Mead drop due to prolonged drought, a growing number of people are taking this idea more seriously.

Paradoxically, two of the Colorado River’s most important wetlands for wildlife are the product of runoff from irrigated farm fields — and are now at risk from a changing climate and agreements to reduce water use.

In the Sonoran Desert of northwestern Mexico, the 40,000-acre La Cienega de Santa Clara wetland was inadvertently created in the 1970s when U.S. officials built a canal to dispose of salty wastewater from agricultural fields in Arizona. As the water began spilling into the desert, myriad forms of life began to appear. Now its cattail-studded marshes and mudflats are considered one of the most important wetlands in North America, home to 280 species of birds — including the endangered Ridgeways rail — on what was once hard-baked desert.

Meanwhile, in California, the Salton Sea was once a shallow inland lake whose levels routinely fluctuated. In 1905, an effort to increase Colorado River flow into the Imperial Valley led farmers to allow too much river water into their irrigation canal, overwhelming their system; for two years the water poured into the 35-mile-long, 15-mile-wide Salton Sea and expanded it.

But as less water becomes available to agriculture and rising temperatures cause more water to evaporate, scientists are concerned that these wetlands will dry and shrink faster than they already have. A 2003 agreement, for example, allows agricultural water in the Imperial Valley to be sent to San Diego for municipal uses. That could cause water levels in the Salton Sea to drop by more than 40 percent, dramatically reducing bird habitat and increasing toxic dust because wetlands would dry out. Local, state, and federal officials have devised a plan — still not fully funded — to restore 15,000 acres of wetlands, at a cost of more than $700 million.

The largest project to restore some semblance of nature to the Colorado River, though, is in the delta. An unusual agreement in 2012 between the U.S. and Mexico, called Minute 319, mandated that the two countries would provide water and funding to revive sections of the delta and release a one-time pulse of 105,000 acre-feet to again connect the river to the delta temporarily. Scientists would then study the effects.

In 2014, for the first time in decades, the river flowed again in Mexico — for eight weeks. San Luis Rio Colorado — once a Colorado River town, but now a dusty desert settlement — became a river town for two months, to the delight of locals, many of whom had never seen the river. The pulse offered a glimpse of what reclamation efforts might look like. “It gave us an idea of how the river behaves, and the best sites for restoration,” said Zamora.

Martha Gomez-Sapiens, a monitoring team member and postdoctoral research associate in the UA Department of Geosciences, stands on a riverbank next to willows and cottonwoods that germinated as a result of the pulse flow. (Photo: Karl W. Flessa/UA Department of Geosciences)

Minute 319 and its 2017 replacement, Minute 323, have funded the restoration of sections of the river. A group of nonprofits — including the National Audubon Society, the Sonoran Institute, The Nature Conservancy, and a Mexican group called Pronatura Noroeste — is working on a project called Raise the River to revive a significant swath of the delta.

In 2008, the group secured rights to 1,200 acres along the desiccated river channel. Since then, local residents have torn out acres of salt cedar and planted irrigated fields of cottonwood, willow, and other endemic species — more than 200,000 trees in all. A small supply of water mandated by the treaty, along with excess water that flows off of irrigated fields, have been dedicated to the restoration.

On a recent visit, I joined Zamora and botanist Celia Alvarado on a short boat ride to Laguna Grande, a 6-mile section of restored river and estuary. We skimmed across still water the color of weak tea, minnows darting away from our paddles. Thick groves of cottonwoods and willows lined the river. Zamora remarked that bobcats and beaver lived there now, along with blue grosbeaks and yellow-billed cuckoos. “Impacting the target species is key,” he said.

And what about the jaguar? I asked. It has not returned, he said. Will it come back?

“Yes,” said Zamora, smiling. “Someday. If they allow me to introduce them.”

The @CWCB_DNR February 2019 “CWCB Confluence Newsletter” is hot off the presses

Platte River photo credit US Bureau of Reclamation.

Click here to read the newsletter. Here’s an excerpt:

The Platte River Recovery Implementation Program

The Platte River Recovery Implementation Program is an innovative and successful approach to endangered species recovery and water development in Colorado. For almost 13 years, this program has been running smoothly in the background allowing for economic growth in the North and South Platte Basins, as well as species conservation in the Central Platte. Now, Colorado and other partners are taking steps to extend the program for another 13 years. Program partners are confident that the success of the program will speak for itself during the process of seeking congressional re-authorization. Learn more about what the CWCB and program partners are doing to reauthorize the Platte River Recovery Implementation Program in this article.

@USBR Releases Draft Environmental Documents for Platte River Recovery Extension

Here’s the release from the Bureau of Reclamation (Brock Merrill):

The Bureau of Reclamation has released the Final Environmental and Biological Assessment (EA) and signed the Finding of No Significant Impact (FONSI) for the Platte River Recovery Implementation Program, Proposed First Increment Extension. Reclamation, working with the states of Wyoming, Colorado, and Nebraska, water users, and environmental and conservation organizations, proposes to extend the First Increment of the basin-wide, cooperative Recovery Implementation Program by 13 years. Reclamation participates in the Program to meet its obligations under the Endangered Species Act.

The purpose of this action is to continue implementing Program projects in order to accomplish the following:

  • Reduce flow shortages in the Platte River aimed at conforming with U.S. Fish and Wildlife Service target flows
  • Continue land management activities necessary to provide habitat for target threatened and endangered species
  • Continue integrated monitoring, research, and adaptive management, in order to assess the progress of the Program and inform future management decisions
  • The final EA and FONSI evaluates and discloses the potential impacts of the proposed 13 year extension of the Program’s First Increment. The final EA and FONSI does not represent the final decision of the Secretary of the Interior, in cooperation with the Governors of the states of Colorado, Nebraska, and Wyoming, to extend the Program. The final EA and FONSI informs the Secretary that the potential impacts of the proposed extension do not warrant the preparation of an Environmental Impact Statement. The formal decision by the Secretary regarding whether or not to extend the Program in cooperation with the Governors will occur at a later date.

    The final EA and FONSI are available for viewing at http://www.usbr.gov/gp/nepa/platte_river/index.html. For additional information or to receive a printed copy of the EA or Draft FONSI, please contact Brock Merrill at 307-532-1093 or bemerrill@usbr.gov.

    The Platte River is formed in western Nebraska east of the city of North Platte, Nebraska by the confluence of the North Platte and the South Platte Rivers, which both arise from snowmelt in the eastern Rockies east of the Continental Divide. Map via Wikimedia.

    Razorback suckers are hanging on in the San Juan River

    From The Denver Post (Bruce Finley):

    U.S. Fish and Wildlife Service biologists counted 50 yearling razorbacks during a recent survey in the upper Colorado River Basin — the result of water releases in 2016 and 2017 from the Navajo Reservoir aimed at helping the fish, agency officials said this week.

    Federal operators of the reservoir let out 5,000 cubic feet of water per second for 50 days, more than doubling regular flows in the San Juan River. This increased flow created nursery pools, the habitat razorbacks and three other endangered native fish need to spawn and survive.

    Saving razorbacks and other fish “is going to be totally dependent ” on putting more water into rivers, said Tom Chart, director of the Upper Colorado River Endangered Fish Recovery Program, a 25-year, $360 million government-run rescue effort.

    “We’re not going to be able to restore the natural hydrological conditions. We understand that,” Chart said. “But we can recreate conditions that help young fish much more regularly.”

    Yet the intensifying climate shift toward heat and aridity in Southwestern states, combined with population growth, constrains biologists’ push to put more water into rivers for environmental purposes. No water could be released this year from the Navajo Reservoir, which straddles Colorado and New Mexico and holds 1.7 million acre-feet, Bureau of Reclamation engineer Susan Behery said. Probably none will be spared next year, either, because water managers are prioritizing storage after a near-record low snow year left the reservoir half full.

    Raising, stocking razorbacks

    For more than 30 years, federal biologists responsible for emergency rescues of endangered species have relied on raising razorbacks in hatcheries and copiously stocking them into Colorado River tributaries. Razorbacks evolved in wild free-flowing rivers, enduring for millions of years, until widespread dams and diversions reduced and regularized nature’s fluctuating flows. The razorback had nearly blinked out by 1980 with only 100 survivors — weakened by the disruption of flows and attacked by non-native predators such as bass, walleye and pike that state wildlife agencies have introduced for recreational sport fishing…

    Federal survey crews counted the 50 yearling razorbacks along the San Juan River downriver from the Navajo Reservoir. That’s the most fish counted since the surveys began two decades ago. Fish and Wildlife Service biologists calculated that this many yearlings could mean there are thousands of razorbacks along a 180-mile stretch of the river before it reaches Lake Powell.

    Navajo tribal biologists have embraced the effort to save razorbacks and other imperiled native fish. A Navajo team this year helped move 300 razorbacks over a barrier for spawning while weeding out non-native predators.

    “We are trying to preserve the razorback for our future generations,” said Navajo fish biologist Jerrod Bowman. “So that our kids can see razorbacks. … Our numbers are really looking great.”

    “Far from the self-sustaining populations”

    The problem with officially upgrading the status of fish, Bowman said, is that just the presence of yearlings may not establish that a species has become self-sustaining as required. Razorbacks usually don’t reproduce until they’re at least 2 years old. Adults can live up to 40 years.

    Under President Donald Trump, federal wildlife officials have faced pressure to upgrade and de-list endangered species when scientists still aren’t certain about survival, said ecologist Taylor McKinnon, a public lands campaigner for the Center for Biological Diversity.

    #ColoradoRiver: The Humpback Chub and Razorback Sucker, are making a comeback #COriver

    From WesternSlopeNow.com (Colette Bordelon):

    Our local Fish and Wildlife Conservation Office said they release around 20,000 endangered fish from the hatchery every year. “We’re the ones who have almost taken them out, and I feel like it’s our job to recover them, and so that’s why I do what I do,” said Dale Ryden, a project leader at the Fish and Wildlife Conservation Office.

    Those with the local office also said several factors made the fish endangered in the first place, including a lack of water and nonnative fish, as well as barriers like dams and reservoirs. Right now, the Humpback Chub, Bonytail, Colorado Pikeminnow, and Razorback Sucker are all listed as endangered species’. “Fish and Wildlife service established the Endangered Species Act back in 1973, and two of our species were immediately on the list: Humpback Chub and Razorback Sucker,” said Tom Chart, the program director for the Upper Colorado River Endangered Fish Recovery Program.

    Those two species, the Humpback Chub and Razorback Sucker, are making a comeback. The recent proposal by scientists with the Fish and Wildlife Service that suggested moving them from endangered to threatened would require the public’s comments in the future. “I don’t know that they would be possibly downlisted if it wouldn’t have been for the Endangered Species Act years ago,” said Mike Gross, a fish culturist at the Fish and Wildlife Conservation Office.

    The latest E-Newsletter is hot off the presses from the Hutchins Water Center

    What’s for breakfast, in the Grand. Photo: via Aspen Journalism

    Click here to read the newsletter. Here’s an excerpt:

    GRAND CANYON ENVIRONMENT

    This in-depth feature from the Arizona Republic reviews how dams and water management have thoroughly altered the environment in the Grand Canyon, and how some of those alterations could now be, paradoxically, protecting native fish.

    First efforts to revive populations of #Colorado’s state fish seemed fruitless. Then the #greenback cutthroat trout surprised everyone — again — @ColoradoSun

    Greenback cutthroat trout photo credit: Colorado Parks and Wildlife.

    From The Colorado Sun (Jesse Paul):

    The species — previously considered extinct — is thriving in Herman Gulch, off Interstate 70, after initial stocking attempts now appear to be successful

    Colorado Parks and Wildlife biologists first tried to reproduce and reintroduce the greenback cutthroat trout into a stream, not far from Interstate 70 and the Eisenhower-Johnson Tunnel, in the summer of 2016.

    When they returned the next summer, the results were grim. Researchers examining the ribbon of stream that winds down Herman Gulch found that none of the thousands of inch-long swimmers that were hauled up a steep trail by volunteers and placed in the waterway had survived.

    But as history has shown, there’s never really an end to the story of the ancient, threatened greenback cutthroat trout.

    A few months later, in September 2017, there was a good sign.

    “Lo and behold, we found some of the fish that we stocked as young-of-year in September 2016,” said Boyd Wright, a native aquatic species biologist for Colorado Parks and Wildlife’s northeast region. “We thought that it was a failed plant. We are seeing those fish, albeit in a very low percentage of what we stocked out.”

    The news for greenbacks got better from there.

    The creek has been stocked five times since 2016. Last year, CPW put in older fish, some of which were about 5 inches long.

    “The real success story, I think, right now is with those fish we stocked last year as 1-year-olds,” Wright said. “We’ve seen on average about 35 percent survival on those. We’re really happy with that level of success. A year later, they’ve lived through a winter, they’ve lived through a runoff cycle. That’s significant.”

    State wildlife officials chose the Herman Gulch stream, near a popular hiking trail, because a barrier where it spills into Clear Creek near I-70 prevents other types of trout — browns, brooks and rainbows — from sullying the genetics of the pure greenback population.

    Before stocking the greenbacks, biologists remove other trout species from the creek.

    CPW says the retention rate of the greenbacks in Herman Gulch is an encouraging sign for projects that the agency is working on to reintroduce the fish in other watersheds…

    Greenbacks are being stocked in Dry Gulch, near Herman Gulch, and there are two more streams where CPW is building barriers — at a cost of about $250,000 — to stock the trout and keep other species out.

    “Everything we know about this system tells us that it should support a population of native trout,” Wright said of Herman Gulch. “For us, we expect to have reproductively mature fish by 2019 and will best be able to detect if those fish reproduce successfully by 2020. If we see 1-year-old fish in the system in 2020, we know we had good, successful reproduction in 2019. I think 2020 is going to be a big year for this project.”

    The hope is then to replicate that success elsewhere…

    That passion for the greenbacks and for fishing was on display on a recent weekday morning. Several dozen volunteers from Trout Unlimited gathered with CPW officials waiting for a truck filled with thousands of tiny greenback cutthroats to arrive from Mount Shavano Fish Hatchery near Salida.

    They huddled together in the chilly wind since the truck was more than an hour late. But they didn’t care about the delay.

    “It’s pretty amazing to see not only the fish take hold, but the people it brings out in support of this,” Omasta said of the different people involved in hauling the trout up to Herman Gulch. “Just this past summer we had families, we had kids from middle school and a high school, walking alongside old fishermen.”

    The volunteers fashioned an informal line as they waited for sloshing, 2-foot-tall, clear-plastic bags, each filled with 500 tiny greenbacks. They stuffed the bags into backpacks and headed uphill to free them into Herman Gulch.

    As volunteer Brett Piché strolled up to the stream, several 5- or 6-inch greenbacks darted back and forth in the water. Piché placed his bag of fish in the water and, after a few minutes, carefully released its contents into the crystal-clear stream.

    Immediately, a larger greenback swam up and gobbled a few of its smaller brethren and darted away.

    Herman Gulch via TheDenverChannel.com