Characteristics and function of large woody debris in subalpine Rocky Mountain streams in northern Colorado

1995 ◽  
Vol 52 (8) ◽  
pp. 1789-1802 ◽  
Author(s):  
Ann D. Richmond ◽  
Kurt D. Fauseh
Keyword(s):  
Pacific Northwest ◽  
Woody Debris ◽  
Fish Habitat ◽  
Rocky Mountain ◽  
Large Woody Debris ◽  
Mountain Streams ◽  
Coastal Forests ◽  
The Pacific ◽  
And Function ◽  
Rocky Mountain Streams

Large woody debris has been well studied in coastal forests of the Pacific Northwest, but little is known of its role in Rocky Mountain streams. Large woody debris was measured in 11 undisturbed streams draining subalpine old-growth forests in north central Colorado to assess abundance, characteristics, and function. Although large woody debris in Colorado had smaller diameter, length, and volume than in the Pacific Northwest, its abundance and function were similar. The majority of pools (76%) were plunge and dammed pools formed by large woody debris, most of which spanned the channels perpendicular to stream flow. Smaller streams had a greater proportion of such perpendicular pool-forming pieces than larger streams. Four disturbed streams had significantly less and smaller large woody debris than undisturbed streams. Flows in larger undisturbed streams were capable of moving large woody debris, so pieces were more often located at the stream margins, oriented diagonally, or distributed in clumps than in smaller streams. Individual pools were larger and deeper in larger streams, but their size was not related to the size of large woody debris pieces forming them. Therefore, the function of large woody debris in forming fish habitat in small Rocky Mountain streams is strongly influenced by the stream's location within the watershed.

Large woody debris in bull trout (Salvelinus confluentus) spawning streams of logged and wilderness watersheds in northwest Montana

1999 ◽  
Vol 56 (6) ◽  
pp. 915-924 ◽  
Author(s):  
F Richard Hauer ◽  
Geoffrey C Poole ◽  
John T Gangemi ◽  
Colden V Baxter
Keyword(s):  
Woody Debris ◽  
Rocky Mountain ◽  
Large Woody Debris ◽  
Mountain Streams ◽  
Bull Trout ◽  
Stream Channel ◽  
Salvelinus Confluentus ◽  
Stream Bank ◽  
Northwestern Montana ◽  
Bankfull Width

We measured large woody debris (LWD) in 20 known bull trout (Salvelinus confluentus) spawning stream reaches from logged and wilderness watersheds in northwestern Montana. Mean bankfull width of stream reaches was 14.1 m ranging from 3.9 to 36.7 m. Streams were large enough to move LWD and form aggregates. We determined the characteristics of individual pieces of LWD that were interactive with the stream channel. Large, short pieces of LWD attached to the stream bank were the most likely to be positioned perpendicular to stream flow, while large, long pieces either tended to be parallel to the flow or, when attached, were most apt to extend across the channel thalweg. Observations indicated that the majority of pools were formed as scour pools by either very large LWD pieces that were perpendicular to the stream or multipiece LWD aggregates. Among reaches in wilderness watersheds, ratios of large to small LWD, attached to unattached LWD, and with and without rootwads were relatively consistent. However, among reaches with logging in the watershed, these ratios varied substantially. These results suggest that logging can alter the complex balance of delivery, storage, and transport of LWD in northern Rocky Mountain streams, and therefore, the likely substantive change in stream habitats.

Are trout populations affected by reach-scale stream slope?

2000 ◽  
Vol 57 (2) ◽  
pp. 468-477 ◽  
Author(s):  
Daniel J Isaak ◽  
Wayne A Hubert
Keyword(s):  
Species Composition ◽  
Spatial Scale ◽  
Relative Abundance ◽  
Cross Sections ◽  
Fish Habitat ◽  
Rocky Mountain ◽  
Mountain Streams ◽  
Habitat Models ◽  
High Slope ◽  
Rocky Mountain Streams

Reach-scale stream slope and the structure of associated physical habitats are thought to affect trout populations, yet previous studies confound the effect of stream slope with other factors that influence trout populations. We isolated the effect of stream slope on trout populations by sampling reaches immediately upstream and downstream of 23 marked changes in stream slope on 18 streams across Wyoming and Idaho. No effect of stream slope on areal trout density was observed, but when trout density was expressed volumetrically to control for differences in channel cross sections among reaches in different slope classes, the highest densities of trout occurred in medium-slope reaches, intermediate densities occurred in high-slope reaches, and the lowest densities occurred in low-slope reaches. The relative abundance of large trout was reciprocal to the pattern in volumetric trout density. Trout biomass and species composition were not affected by stream slope. Our results suggest that an assumption made by many fish-habitat models, that populations are affected by the structure of physical habitats, is at times untenable for trout populations in Rocky Mountain streams and is contingent upon the spatial scale of investigation and the population metric(s) used to describe populations.

Experiments on Oral Secretion of the Rocky Mountain Wood Tick, Dermacentor andersoni Stiles (Acarina: Ixodidae)

1957 ◽  
Vol 89 (1) ◽  
pp. 1-5 ◽  
Author(s):  
J. D. Gregson
Keyword(s):  
British Columbia ◽  
Pacific Northwest ◽  
Rocky Mountain ◽  
Dermacentor Variabilis ◽  
Oral Secretion ◽  
Amblyomma Maculatum ◽  
Dermacentor Andersoni ◽  
The Pacific ◽  
Tick Paralysis ◽  
Rocky Mountain Wood Tick

Tick paralysis continues to be one of the most baffling and fascinating tickborne diseases in Canada. It was first reported in this country by Todd in 1912. Since then about 250 human cases, including 28 deaths, have been recorded from British Columbia. Outbreaks in cattle have affected up to 400 animals at a time, with losses in a herd as high as 65 head. Although the disease is most common in the Pacific northwest, where it is caused by the Rocky Mountain wood tick, Dermacentor andersoni Stiles, it has lately been reported as far south as Florida and has been produced by Dermacentor variabilis Say, Amblyomma maculatum Koch, and A. americanum (L.) (Gregson, 1953). The symptoms include a gradual ascending symmetrical flaccid paralysis. Apparently only man, sheep, cattle, dogs, and buffalo (one known instance) are susceptible, but even these may not necessarily be paralysed.

Responses of Epilithic Algae to Regulation of Rocky Mountain Streams

1987 ◽  
pp. 383-390 ◽  
Author(s):  
R. G. Dufford ◽  
H. J. Zimmermann ◽  
L. D. Cline ◽  
J. V. Ward
Keyword(s):  
Rocky Mountain ◽  
Mountain Streams ◽  
Epilithic Algae ◽  
Rocky Mountain Streams

Keepability of Pennsylvania versus West Coast Grown Douglas-Fir Christmas Trees: Genotypic Variation in Relation to Subfreezing Temperatures

1990 ◽  
Vol 7 (2) ◽  
pp. 86-89 ◽  
Author(s):  
Mark E. Kubiske ◽  
Marc D. Abrams ◽  
James C. Finley
Keyword(s):  
Pacific Northwest ◽  
Genotypic Variation ◽  
Rocky Mountain ◽  
Douglas Fir ◽  
Seed Sources ◽  
Christmas Trees ◽  
Display Area ◽  
The Pacific ◽  
Significant Difference ◽  
Needle Loss

Abstract Cut Douglas-fir Christmas trees grown in Pennsylvania from Rocky Mountain seed sources and coastal trees grown in the Pacific Northwest and shipped into Pennsylvania were compared for keepability. Following various cold treatments, the cut ends of trees were placed in water in an indoor display area. Coastal trees placed in a freezer at - 29°C for 24 h had 89 ± 5.1% (mean ± standard error) needle loss after one day of display, while Rocky Mountain origin trees exhibited only 3 ± 2.0% needle loss after 1 day and 50 ± 5.6% needle loss after 18 days. Coastal produced trees exposed to temperatures > - 12°C had 50 ± 9.8% needle loss at the end of the experiment, while Rocky Mountain trees ended with 22 ± 3.2% needle loss. Four additional treatments consisted of trees placed on an outdoor lot and periodically moved indoors to simulate Christmas tree market activity. Again, there was a significant difference between trees from coastal and Rocky Mountain sources, with 57.2 ± 4.3% and 11.8 ± 1.2% needle loss after 3 days, respectively. By the end of the 23 day experiment, the coastal trees were essentially devoid of needles, whereas Rocky Mountain trees had an average of only 20% needle loss. Coastal trees also exhibited a very noticeable loss of color and lustre. North. J. Appl. For. 7:86-89, June 1990.

scholarly journals The Concept of Place in the American West

Linguaculture ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 46-59
Author(s):  
Irina Chirica
Keyword(s):  
Pacific Northwest ◽  
Visual Arts ◽  
American West ◽  
Rocky Mountain ◽  
New Historicism ◽  
The West ◽  
John Ford ◽  
The Pacific ◽  
Louisiana Purchase ◽  
Cultural Concept

This paper surveys the most significant ways in which the American West has been viewed as a place and region. Starting with Thomas Jefferson’s Louisiana Purchase of 1803, we follow the expansion of the West as a region throughout American history. Jefferson worked out a plan which involved the creation of territories which later became states, following a certain procedure. Inside the larger West, there are many Wests: the prairie states of the Midwest (also called the “Bread Basket” of America), the Rocky Mountain states, the Pacific Northwest, the Southwest and California. We analyze the myths and images associated with the west in American culture, and the influence of Frederick Jackson Turner’s essay dedicated to “the Frontier”. We discuss the New Historicism approach and the way in which it criticizes Tuner. Then we discuss the reflection of the West in the visual arts (the major landscape painters and in the work of the western movie director John Ford). We bring arguments to support the idea that the West is a construct of human experience and a cultural concept, more than a “place”.

Sign in / Sign up

Export Citation Format

Share Document