Posts tagged trout
FLY FISHING THE SEASONS IN COLORADO by Ron Baird— just in time for Spring
Mar 8th
FLY FISHING THE SEASONS IN COLORADO
An Essential Guide for Fishing through the winter, Spring, Summer and Fall
Author Ron Baird
“The single most important factor that determines a fly angler’s approach to a stretch of water isn’t the time of day, nor is it a hatch of insects or even the character of the water itself. It’s the season. From spring and summer through fall and winter, changes in weather dictate changes in strategy. This can be intimidating. If fish were biting here a month ago, why are things so different now? Where to go where they might be better? The seasonal variation of fishing strategy is necessary knowledge for any fly angler, and Fly Fishing the Seasons: Colorado is the first-ever guidebook to address this subject.”
Focusing on the world-class waters of the Centennial State, and with full-color photos throughout, this book comprises four equal sections—summer, fall, winter, and spring—each with a general locator map and each covering five to ten primary locations. The best waters to fish in this particular month or span of months? What flies and techniques to use? Look no further than Fly Fishing the Seasons in Colorado.”
Ron Baird worked for the Colorado Division of Wildlife, where he researched and wrote about fishing spots for anglers visiting our state. His first book was Fishing Colorado. His new book Fly Fishing the Seasons in Colorado was released just in time for Christmas. It is available in book stores and fly shops all over Colorado or world-wide on Amazon.com
Mr. Baird is the news editor for Boulder Channel 1 and Channel One Networks
New CU-Boulder study clarifies diversity, distribution of cutthroat trout in Colorado
Sep 24th
A novel genetic study led by the University of Colorado Boulder has helped to clarify the native diversity and distribution of cutthroat trout in Colorado, including the past and present haunts of the federally endangered greenback cutthroat trout.
The study, led by CU-Boulder postdoctoral researcher Jessica Metcalf, was based largely on DNA samples taken from cutthroat trout specimens preserved in ethanol in several U.S. museums around the country that were collected from around the state as far back as 150 years ago. The new study, in which Metcalf and her colleagues extracted mitochondrial DNA from fish to sequence genes of the individual specimens and compared them with modern-day cutthroat trout strains, produced some startling results.
The biggest surprise, said Metcalf, was that the cutthroat trout native to the South Platte River drainage appears to survive today only in a single population outside of its native range — in a small stream known as Bear Creek that actually is in the nearby Arkansas River drainage. The strain from Bear Creek is thought to have been collected from the South Platte River drainage in the 1880s by an early hotelier who stocked the fish in a pond at the Bear Creek headwaters to help promote an early tourist route up Pikes Peak.
“We thought one way to get to the question of which cutthroat trout strains are native to particular drainages was to go back to historical samples and use their DNA as a baseline of information,” said Metcalf of the chemistry and biochemistry department and a former postdoctoral researcher at the Australian Centre for Ancient DNA. “Our study indicates the descendants of the fish that were stocked into Bear Creek in the late 1800s are the last remaining representatives of the federally protected greenback cutthroat trout.”
A second, key set of data was all of the Colorado cutthroat trout stocking records over the past 150 years, a task spearheaded by study co-author and fish biologist Chris Kennedy of the U.S. Fish and Wildlife Service. Between 1889 and 1925, for example, the study showed that more than 50 million cutthroat trout from the Gunnison and Yampa river basins were stocked in tributaries of all major drainages in the state, jumbling the picture of native cutthroat strains in Colorado through time and space.
Originating from the Pacific Ocean, cutthroat trout are considered one of the most diverse fish species in North America and evolved into 14 recognized subspecies in western U.S. drainages over thousands of years. In Colorado, four lineages of cutthroats were previously identified: the greenback cutthroat, the Colorado River cutthroat, the Rio Grande cutthroat and the extinct yellowfin cutthroat.
The museum specimens used in the study came from the California Academy of Sciences, the Smithsonian Museum of Natural History in Washington, D.C., the Academy of Natural Sciences in Philadelphia and the Harvard University Museum of Comparative Zoology. Colorado cutthroat trout specimens were collected by a number of early naturalists, including Swiss scientist and former Harvard Professor Louis Agassiz and internationally known fish expert and founding Stanford University President David Starr Jordan.
The new study, published online today in Molecular Ecology, follows up on a 2007 study by Metcalf and her team that indicated there were several places on the Front Range where cutthroat populations thought to be greenbacks by fish biologists were actually a strain of cutthroats transplanted from Colorado’s Western Slope in the early 1900s.
Other co-authors on the new study included CU-Boulder Professor Andrew Martin and CU-Boulder graduate students Sierra Stowell, Daniel McDonald and Kyle Keepers; Colorado Parks and Wildlife biologist Kevin Rogers; University of Adelaide scientists Alan Cooper and Jeremy Austin; and Janet Epp of Pisces Molecular LLC of Boulder.
“With the insight afforded by the historical data, we now know with a great deal of certainty what cutthroat trout strains were here in Colorado before greenbacks declined in the early 20th century,” said Martin of CU’s ecology and evolutionary biology department. “And we finally know what a greenback cutthroat trout really is.”
Metcalf and her colleagues first collected multiple samples of tissue and bone from each of the ethanol-pickled trout specimens, obtaining fragments of DNA that were amplified and then pieced together like a high-tech jigsaw puzzle to reveal two genes of the individual specimens. The tests were conducted on two different continents under highly sterile conditions and each DNA sequencing effort was repeated several times for many specimens to ensure accuracy in the study, Metcalf said.
Roughly half of the study was conducted at CU-Boulder and half at the Australian Center for Ancient DNA at the University of Adelaide, where Metcalf had worked for two years. “By conducting repeatable research at two very different, state-of-the-art laboratories, we were able to show the Bear Creek trout was the same strain as the cutthroats originally occupying the South Platte River drainage.”
The Bear Creek trout strain is now being propagated in the Colorado Parks and Wildlife hatchery system and at the USFWS Leadville National Fish Hatchery.
In addition to identifying the Bear Creek cutthroat trout, Metcalf and her colleagues discovered a previously unknown cutthroat strain native to the San Juan Basin in southwestern Colorado that has since gone extinct. The study also confirmed that the yellowfin cutthroat, a subspecies from the Arkansas River headwaters that grew to prodigious size in Twin Lakes near Leadville, also had gone extinct.
Fortunately, most fish preserved by naturalists before 1900 were “fixed” in ethanol, which makes it easier for researchers to obtain reliable DNA than from fish preserved in a formaldehyde solution, a practice that later became popular. Prior to the new study — which included DNA from specimens up to about 150 years old — scientists working in ancient DNA labs had only performed similar research on ethanol-preserved museum vertebrate specimens less than 100 years old.
“One of the exciting things to come from this research project is that it opens up the potential for scientists to sequence the genes of other fish, reptiles and amphibian specimens preserved in ethanol further back in time than ever before to answer ecological questions about past diversity and distribution,” said Metcalf, who conducts her research at CU’s BioFrontiers Institute.
Funding for the study was provided by agencies of the Greenback Cutthroat Trout Recovery Team, including the USFWS, the U.S. Forest Service, the Bureau of Land Management, the National Park Service and Trout Unlimited.
“I think in many cases success depends less on the application of a new technology and more on the convergence of people with shared interest and complementary skills necessary for solving difficult problems,” said Martin. “Our greenback story is really one about what can be discovered when dedicated and talented people collaborate with a shared purpose.”
“We’ve known for some time that the trout in Bear Creek were unique,” said Doug Krieger, senior aquatic biologist for Colorado Parks and Wildlife and the Greenback Cutthroat Trout Recovery Team leader. “But we didn’t realize they were the only surviving greenback population.”
The decline of native cutthroats in Colorado occurred because of a combination of pollution, overfishing and stocking of native and non-native species of trout, said Metcalf. “It’s ironic that stocking nearly drove the greenback cutthroat trout to extinction, and a particularly early stocking event actually saved it from extinction,” she said.
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CU study: Nitrogen damage to RMNP could become irreversible
Jul 10th
The emissions of nitrogen compounds to the atmosphere are being carried to remote areas of the park, altering sensitive ecosystems, said CU-Boulder Professor William Bowman, who directs CU-Boulder’s Mountain Research Station west of Boulder and who led the study. “The changes are subtle, but important,” he said. “They represent a first step in a series of changes which may be relatively irreversible.”
A new study led by the University of Colorado Boulder indicates air pollution in the form of nitrogen compounds emanating from power plants, automobiles and agriculture is changing the alpine vegetation in Rocky Mountain National Park.
The emissions of nitrogen compounds to the atmosphere are being carried to remote areas of the park, altering sensitive ecosystems, said CU-Boulder Professor William Bowman, who directs CU-Boulder’s Mountain Research Station west of Boulder and who led the study. “The changes are subtle, but important,” he said. “They represent a first step in a series of changes which may be relatively irreversible.”
In other regions of the world, higher amounts of nitrogen pollutants correlate with decreased biodiversity, acidified soils and dead stream organisms like trout, said Bowman. “There is evidence that indicates once these changes occur, they can be difficult if not impossible to reverse. It is best to recognize these early stages before the more harmful later stages happen.”
The study site was an alpine meadow roughly one mile east of Chapin Pass in the Mummy Range of Rocky Mountain National Park. Bowman and his team analyzed the plant communities and soils under ambient levels of nitrogen deposition and compared them to plots with added nitrogen to simulate the increasing atmospheric nitrogen pollution expected in the coming decades. The results indicated changes in plant abundances already were occurring under ambient conditions, but to date no changes in soils were detected.
During the course of the three-year study, rising levels of nitrogen in the soils correlated with large increases in a common species of sedge shown to flourish in other nitrogen addition studies. Bowman said the team anticipates that the diversity of vascular plant species will rise with increasing nitrogen deposition, then decrease with more rare species being excluded by competition from other plant species. “While the changes are relatively modest, they portend that other more environmentally adverse impacts may be on the horizon in Colorado’s alpine areas,” said Bowman.
A paper on the subject was published in the June issue of the Journal of Environmental Management. Co-authors on the study included John Murgel, a former CU-Boulder undergraduate student now completing graduate work at Colorado State University, and Tamara Blett and Ellen Porter of the Air Resources Division of the National Park Service in Lakewood, Colo. The study was funded by the National Park Service.
Previous studies by Bowman and others have shown vegetation changes and soil acidification has been occurring due to increasing nitrogen deposition at other alpine sites in Colorado, including Niwot Ridge. Niwot Ridge is a National Science Foundation-funded Long-Term Ecological Research site administered by CU-Boulder and located adjacent to the university’s Mountain Research Station located some 30 miles west of the city.
Given the projected population growth in Front Range cities in the greater Denver area and increasing agricultural development, nitrogen deposition is expected to increase steadily in Rocky Mountain National Park over the next several decades, said Bowman, a professor in CU-Boulder’s ecology and evolutionary biology department.
The high-elevation ecosystems of the park are a magnet for thousands of visitors each year who have opportunities to see plants and animals well adapted to the severe climate above treeline, said Bowman, but such ecosystems are the most sensitive to adverse impacts from air pollutants. Previous studies by other researchers have documented ongoing changes in the algae found in several of the Rocky Mountain National Park’s high elevation lakes due to nitrogen pollution, he said.
While the park is also a haven for fishermen hoping to catch trout in pristine waters, continued inputs of nitrogen pollutants are a hazard to the health of both trout and their food sources, said Bowman, also a fellow of CU-Boulder’s Institute of Arctic and Alpine Research. It starts when the ability of the land plants and soils to take up the nitrogen is exceeded, causing soils to become acidified, he said.
Other parts of the Colorado Front Range have exhibited signs of acidification at the highest elevations, Bowman said. “Once this happens, soluble aluminum leaches from soils and begins to show up in streams and lakes. This aluminum is quite toxic to many aquatic animals,” he said.
“The take-home message is that the amount of nitrogen deposition reaching the tundra in Rocky Mountain National Park has already passed an important threshold and may lead to more serious environmental impacts,” said Bowman. “It’s not inconceivable that continued negative ecological impacts in the park due to nitrogen pollution could eventually impact tourism in Colorado.”
Officials from Environmental Defense and Trout Unlimited petitioned the State of Colorado and the Environmental Protection Agency to reduce emissions of nitrogen pollution in 2004. This effort resulted in a 2007 plan to lower nitrogen emissions on a voluntary basis to reduce impacts to Rocky Mountain National Park.
Excel Energy’s recent switch to natural gas in some of its power plants is one of many steps toward limiting nitrogen emissions, said Bowman. Ongoing efforts by air quality managers and representatives from the Colorado agricultural industry are also working on management practices that would lower nitrogen emissions.
In other regions of the world, higher amounts of nitrogen pollutants correlate with decreased biodiversity, acidified soils and dead stream organisms like trout, said Bowman. “There is evidence that indicates once these changes occur, they can be difficult if not impossible to reverse. It is best to recognize these early stages before the more harmful later stages happen.”
The study site was an alpine meadow roughly one mile east of Chapin Pass in the Mummy Range of Rocky Mountain National Park. Bowman and his team analyzed the plant communities and soils under ambient levels of nitrogen deposition and compared them to plots with added nitrogen to simulate the increasing atmospheric nitrogen pollution expected in the coming decades. The results indicated changes in plant abundances already were occurring under ambient conditions, but to date no changes in soils were detected.
During the course of the three-year study, rising levels of nitrogen in the soils correlated with large increases in a common species of sedge shown to flourish in other nitrogen addition studies. Bowman said the team anticipates that the diversity of vascular plant species will rise with increasing nitrogen deposition, then decrease with more rare species being excluded by competition from other plant species. “While the changes are relatively modest, they portend that other more environmentally adverse impacts may be on the horizon in Colorado’s alpine areas,” said Bowman.
A paper on the subject was published in the June issue of the Journal of Environmental Management. Co-authors on the study included John Murgel, a former CU-Boulder undergraduate student now completing graduate work at Colorado State University, and Tamara Blett and Ellen Porter of the Air Resources Division of the National Park Service in Lakewood, Colo. The study was funded by the National Park Service.
Previous studies by Bowman and others have shown vegetation changes and soil acidification has been occurring due to increasing nitrogen deposition at other alpine sites in Colorado, including Niwot Ridge. Niwot Ridge is a National Science Foundation-funded Long-Term Ecological Research site administered by CU-Boulder and located adjacent to the university’s Mountain Research Station located some 30 miles west of the city.
Given the projected population growth in Front Range cities in the greater Denver area and increasing agricultural development, nitrogen deposition is expected to increase steadily in Rocky Mountain National Park over the next several decades, said Bowman, a professor in CU-Boulder’s ecology and evolutionary biology department.
The high-elevation ecosystems of the park are a magnet for thousands of visitors each year who have opportunities to see plants and animals well adapted to the severe climate above treeline, said Bowman, but such ecosystems are the most sensitive to adverse impacts from air pollutants. Previous studies by other researchers have documented ongoing changes in the algae found in several of the Rocky Mountain National Park’s high elevation lakes due to nitrogen pollution, he said.
While the park is also a haven for fishermen hoping to catch trout in pristine waters, continued inputs of nitrogen pollutants are a hazard to the health of both trout and their food sources, said Bowman, also a fellow of CU-Boulder’s Institute of Arctic and Alpine Research. It starts when the ability of the land plants and soils to take up the nitrogen is exceeded, causing soils to become acidified, he said.
Other parts of the Colorado Front Range have exhibited signs of acidification at the highest elevations, Bowman said. “Once this happens, soluble aluminum leaches from soils and begins to show up in streams and lakes. This aluminum is quite toxic to many aquatic animals,” he said.
“The take-home message is that the amount of nitrogen deposition reaching the tundra in Rocky Mountain National Park has already passed an important threshold and may lead to more serious environmental impacts,” said Bowman. “It’s not inconceivable that continued negative ecological impacts in the park due to nitrogen pollution could eventually impact tourism in Colorado.”
Officials from Environmental Defense and Trout Unlimited petitioned the State of Colorado and the Environmental Protection Agency to reduce emissions of nitrogen pollution in 2004. This effort resulted in a 2007 plan to lower nitrogen emissions on a voluntary basis to reduce impacts to Rocky Mountain National Park.
Excel Energy’s recent switch to natural gas in some of its power plants is one of many steps toward limiting nitrogen emissions, said Bowman. Ongoing efforts by air quality managers and representatives from the Colorado agricultural industry are also working on management practices that would lower nitrogen emissions.