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Return to the: DNR Homepage or Type 5 Stream Literature Review (main DNR site)
How do Type 5 streams contribute to the riparian conservation strategy?
Statements within this literature review are based on the reported findings from various published sources. Due to differences in sample design, methodology, geographical location, site characteristics, data analysis and interpretation, these statements may or may not agree with the results of other published reports. Despite contradictory results, one cannot say the findings of one author are more or less valid than another, due to the wide range of site characterists. Readers are urged to consider how and where information was collected when interpreting the value of the following conclusions. Headwater stream science is, in many ways, a relatively new field. Early observations and case studies may or may not represent widespread relationships.
Click on the citation following each statement to view the annotated bibliography
- The data suggested
that invertebrate inputs are higher in these Alder (Alnus rubra)
dominated stands of south eastern Alaska. As in western Washington,
these streams are classified as relatively unproductive. (Allan
et al. 2003).
- Approximately 1/3
of juvenile coho (Oncorhynchus kisutch) diets consisted of
terrestrial invertebrates. (Allan
et al. 2003).
- Riparian buffers
with a heterogenous overstory and understory supply "variation
in quantity, composition, and timing of terrestrial invertebrates."
(Allan
et al. 2003).
- Depletion or exclusion
of terrestrial prey, usually results in a behavioral response by fish
populations to emmigrate to areas were prey is more abundant. (Baxter
et al. 2005).
- Fish prefer terrestrial
prey over benthic prey, because benthic organisms are often smaller
and more difficult to catch. (Baxter et al. 2005).
- Fish production was
greater in the clear cut/ buffered site, because the fish populations
depend on food delivered from allochthonous pathways. (Bilby
and Bisson 1992).
- Fish are more closely
associated with in-stream habitat, rather than with riparian conditions.
For example, Cutthroat trout (Oncorhynchus clarki clarki) prefer streams
with adequate pool habitat. This species in not a good indicator of
riparian health.(Bisson
et al. 1996)
- Torrent sculpins
(Cottus rhotheus) were found more often in streams with an
abundance of pools and mid-seral riparian areas. (Bisson
et al. 1996).
- Coastrange sculpins
(Cottus aleuticus) are more common in low elevation streams
with adequate pool habitat. C. aleuticus is rarely found
in late-seral riparian areas. (Bisson
et al. 1996).
- Tailed frogs (Ascaphus
truei) are associated with late-seral riparian forests. (Bisson
et al. 1996).
- The authors agree
that fish are generally less abundant in old growth streams with high
elevations, and a history of landslides. (Bisson
et al. 1996).
- Amphibians are more
abundant in high elevation, steep gradient, montane streams, than
in low elevation, coastal streams. The researchers also found that
the amphibians favored late-seral over early-seral riparian forests.
This suggests that amphibian populations are negatively affected by
timber removal. (Bisson
et al. 1996).
- Coho use ephemeral,
and intermittent streams for off-channel overwintering habitat. Overwintering
in small tributaries increases their chances of survival because it
prevents the entire stock from being wiped out by a catastrophic event,
such as a debris torrent. (Brown
and Hartman 1988).
- By using a stream
flow mixing equation, it was determined that warmer Type 4 waters
would not increase Type 3 water temperatures by more than 0.49 degrees
celsius, provided that the Type 3 reach is at least 7km long. Type
3 waters recieving warmer inflows, will go back to equilibrium within
150m of the Type 4 confluence. (Caldwell
et al. 1991).
- Landslides and debris
torrents are sometimes triggered from forest related practices. This
in turn, increases stream sediment yields. Excessive sediment levels
can have a range of effects on Coho salmon. For example, the survival
of eggs is dependent on well oxygenated water; the infiltration of
fine sediment may lead to egg and alevin suffocation. Disproportioned
suspended sediment levels can also lead to increased stress in juvenile
fish. Overwintering refugia for smolts may be reduced from increasing
sediment yields. Additionally, coarse sediment can decrease summer
rearing habitats. And finally, the removal of woody debris can decrease
stream bank stability, which leads to more sediment input. Pool frequency
is often reduced by the above mentioned process. (Cederholm
and Reid 1987).
- Dam break floods
start in first-fifth order streams, and propagate to six order streams.
(Coho and Burges 1991).
- Annual litter input
declines with greater stream order (the smaller the stream the greater
the litter input). This suggests that these low order streams may
deliver organic material downstream to higher order channels. (Connors
and Naiman 1984).
- Summer low flows
are detrimental to salmon because as stream temperatures increase,
dissolved oxygen is reduced. As a result, juvenile steelheads leave
riffles, and go into pools where they face increased competition with
more aggressive Cohos. (Hicks
et al. 1991).
- Alders provide a
good food source for fish and other aquatic organisms. But these benefits
are counteractive in terms of woody debris input, because alder is
generally smaller and has a shorter mean residence time as woody debris,
compared to conifers. (Johnson
and Edwards 2002).
- In the Pacific Northwest,
alder is not comparable to coniferous woody debris inputs because
it is generally smaller in diameter and has a shorter mean residence
time. (Johnson
and Edwards 2002).
- The upper distribution
limits of Oncorhynchus spp. (Rainbow and Cutthroat Trout)
is less influenced by logging practices and more influenced by physical
factors, such as channel gradients, pool abundance, and wetted channel
width. (Latterell
et al. 2003).
- Trout (Oncorhynchus
spp.) are commonly found in gradients exceeding 10%. This study found
that trout can access channels with up to 22% gradients. (Latterell
et al. 2003).
- An essential role
of headwater streams is to process coarse particulate organic matter
and small organic debris, for downstream uptake of nutrients and carbon
by aquatic organisms. (MacDonald
and Ritland 1989).
- Transpiration was higher in young growth stands, compared to old growth stands. (Moore et al. 2004).
- Water use decreases in climax forests due to "age-related changes in whole tree hydraulic conductance, species-related differences in water use and structurally related changes in sapwood area distribution within stands." (Moore et al. 2004).
- Headwater channels
are important sources of sediments, water, and nutrients for downstream
reaches. (Moore
and Richardson 2003).
- Large organic debris
dams store sediment, while also providing structure, and channel stability
to steep low order streams. Disrupting these dams would increase the
amount of bedload transported downstream, possibly effecting salmon
and/or juvenile rearing habitat. (O'Connor
and Hall 1994).
- Nitrogen is removed
from the water column quicker in smaller headwater streams. As nitrogen
levels increase in small streams the capacity to effectively retain
and transform these molecules may become inhibited, allowing a greater
amount of inorganic nitrogen to move downstream. (Peterson
et al. 2001).
- Altering stream flow can have a number of negative cumulative effects including: re-distributing woody debris, alternating the geometry of the channel, and increasing stream scour frequency. These effects might be worsened in areas such as in the transient snow zone, where storms may produce rapid storm run-off or in regions of high precipitation, potentially affecting channel morphology. (Peterson
et al. 1992).
- Young alder stands
export more prey to downstream linkages, than do young conifer stands.
(Piccolo
and Wipfli 2002).
- The results show
that the birds, fish, and small mammals sampled in this study, persist
at buffered and unbuffered sites. However, amphibians were found to
be more sensitive to harvesting. Amphibian abundance and diversity
was highest in old-growth settings, lowest in young unbuffered sites,
and intermediate at second growth sites. (Raphael
et al. 2002).
- The diameter of large
woody debris is the most determinant characteristic that influences
instream pool formation. Pool formation is a function of total woody
debris and diameter distribution. (Rosenfeld
and Huato 2003).
- Larvae of Pacific giant salamanders (Dicamptodon tenebrosus) appear to have behavioral defenses, rather than chemical defenses, to cutthroat trout (Oncorhynchus clarki) because Dicamptodon's were proven palatable to cutthroat trout. When cutthroat chemical cues are present, Dicamptodon larvae tend to take cover in refugia. (Rundio
et al. 2002).
- Bull trout found
in mountainous terrain are affected by bedload scour induced by rain,
and snow events. (Shellberg
2001).
- Basin wide examination
of water, nutrient, and sediment movement is important to connect
upstream forestry practices to downstream fishery resources. (Swanson
et al. 1987).
- Steep basins are
more sensitive to management activities because of the frequency of
mass wasting. (Swanson
et al. 1987).
- Debris flows in low
order channels can block fish passage, but this occurs at the upper
extent of their distribution. (Swanson
et al. 1987).
- Fish can occupy gradients
ranging from 3 - 35%, although the majority are found in gradients
around 15%. (Trotter
2000).
- Fish that occur in
the uppermost headwater reaches (ephemeral and intermittent) include
the following: Oncorhynchus clarkii (cutthroat trout), Oncorhynchus
mykiss (native rainbow trout), Salvelinus
fontinalis (non-native brook trout), Salvelinus confluentus
(bull trout), and Cottus spp. (sculpins). (Trotter
2000).
- Detritus and macroinvertebrates
from headwater streams, most likely contribute substantial amounts
of food to downstream aquatic organisms, particularly salmonid species.
(Wipfli
and Gregovich, 2002).
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