Life histories, production, and microdistribution of two caddisflies (Trichoptera) in a Rocky Mountain stream

This paper reports results of a 2-year study of the caddisflies Oligophlebodes zelti (Limnephilidae) and Neothremma alicia (Uenoidae) in a first-order Rocky Mountain stream of southern Alberta. The Oligophlebodes population had a univoltine cycle: eggs were oviposited in July and August and hatched in about 20 days, and the larvae grew rapidly during the remainder of the ice-free season. Larvae overwintered in the fourth larval instar and molted to the fifth instar the following spring. Pupation occurred in June, and adults started emerging in mid-July. Annual production for the O. zelti population was 116 mg∙m−2∙year−1. The Neothremma population had a 2-year cycle. Eggs apparently hatched after freeze-up. Larvae overwintered in the second instar. Most of the population achieved the third instar by the following July and the fourth instar by August, and spent the second winter in either the fourth or fifth instar. There was about a 3-week prepupal stage the following July and then emergence in July and August. Annual production for the N. alicia population was 103 mg∙m−2∙year−1. Oligophlebodes zelti and N. alicia larvae fed mainly on fine particulate organic matter and diatoms. Both O. zelti and N. alicia larvae were found on rocks only in fast water areas, but the two populations did not inhabit the same riffles. The riffles inhabited by O. zelti were wider with lower slopes and water velocities than riffles dominated by N. alicia larvae. Correlation analysis, using several parameters, indicated that total periphyton of the rocks might be a major factor accounting for O. zelti's distribution. The microdistribution of the N. alicia population was not correlated with any food source.

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The life history of Philocasca alba (Trichoptera: Limnephilidae) in a Rocky Mountain stream

Canadian Journal of Zoology ◽

10.1139/z84-185 ◽

1984 ◽

Vol 62 (7) ◽

pp. 1282-1288 ◽

Cited By ~ 9

Author(s):

R. A. Mutch ◽

G. Pritchard

Keyword(s):

Life History ◽

Life Cycle ◽

Rocky Mountains ◽

Laboratory Experiments ◽

Larval Instar ◽

Rocky Mountain ◽

Mountain Stream ◽

Flight Period ◽

Conifer Needles ◽

History Of

The life cycle of Philocasca alba Nimmo spans 3 years in a cold, second order, subalpine stream in the Rocky Mountains of Alberta. The flight period was from mid-May to late July. Larval instar 1 was found only in August–September; all other four instars were present in samples throughout most of the year. In their third autumn in the stream larvae in the final instar burrowed into gravel, pupated, and overwintered. Growth was confined to the ice-free period, June to November, when larval densities were greatest among deposits of conifer needles, cones, and woody material in pools. Larvae from these detrital accumulations had mainly fragments of conifer needles in their guts, although laboratory experiments showed that larvae could feed and grow on conifer needles only if they were highly conditioned. The later instars, particularly instar V, constituted a much greater than expected proportion of total larvae among submerged bank vegetation in spring and summer and deciduous leaves in autumn. Larvae in these two microhabitats mainly had fragments of moss and fragments of leaves, respectively, in their guts. The importance of moss was confirmed by a field experiment which showed that fifth instar larvae had significantly faster growth rates when fed on detritus supplemented with bank moss than detritus alone or detritus supplemented with deciduous leaves during the autumn.

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The life history of Dicosmoecus atripes (Hagen) (Limnephilidae: Trichoptera) in a Rocky Mountain stream of Alberta, Canada

Canadian Journal of Zoology ◽

10.1139/z83-079 ◽

1983 ◽

Vol 61 (3) ◽

pp. 586-596 ◽

Cited By ~ 7

Author(s):

Vytenis Gotceitas ◽

Hugh F. Clifford

Keyword(s):

Life Cycle ◽

Abiotic Factors ◽

Rocky Mountain ◽

Annual Production ◽

Mountain Stream ◽

Microhabitat Selection ◽

Biomass Turnover ◽

First Instar ◽

History Of ◽

Early Instar

Dicosmoecus atripes (Hagen) has a 2-year life cycle in Dyson Creek, Alberta, a second order foothills stream of the eastern Canadian Rockies. Emergence and oviposition occur from August to mid-October. The first winter is spent as first instar larvae, the second as inactive fifth (final) instars in a form of diapause. No growth was observed in overwintering first instar larvae, and a significant (P < 0.05) weight loss was recorded in overwintering fifth instar larvae. Temperature seems to be the most important factor responsible for the 2-year life cycle. Annual production was estimated at 91.4 mg∙m−2∙year−1, with an annual production and biomass turnover (P/B) ratio of 4.97. Larval diet and microhabitat changed between instars. The proportion of diatoms in the diet of early instar larvae was significantly (P < 0.001) greater than that of third and later instars. Early instar larvae inhabit stream margins, while larvae of third and later instars were mainly found in midstream reaches. Larvae of all instars preferred pools to riffles. Abiotic factors important in microhabitat selection seemed to differ between larval instars.

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Thermal Characteristics of a Beaver Dam Analogues Equipped Spring-Fed Creek in the Canadian Rockies

Water ◽

10.3390/w13070990 ◽

2021 ◽

Vol 13 (7) ◽

pp. 990

Author(s):

Tariq M. Munir ◽

Cherie J. Westbrook

Keyword(s):

Thermal Characteristics ◽

Cutthroat Trout ◽

Rocky Mountain ◽

Optimal Growth ◽

Stream Temperature ◽

Mountain Stream ◽

Suitable Habitat ◽

Restoration Technique ◽

Beaver Dam ◽

In Series

Beaver dam analogues (BDAs) are becoming an increasingly popular stream restoration technique. One ecological function BDAs might help restore is suitable habitat conditions for fish in streams where loss of beaver dams and channel incision has led to their decline. A critical physical characteristic for fish is stream temperature. We examined the thermal regime of a spring-fed Canadian Rocky Mountain stream in relation to different numbers of BDAs installed in series over three study periods (April–October; 2017–2019). While all BDA configurations significantly influenced stream and pond temperatures, single- and double-configuration BDAs incrementally increased stream temperatures. Single and double configuration BDAs warmed the downstream waters of mean maxima of 9.9, 9.3 °C by respective mean maxima of 0.9 and 1.0 °C. Higher pond and stream temperatures occurred when ponding and discharge decreased, and vice versa. In 2019, variation in stream temperature below double-configuration BDAs was lower than the single-configuration BDA. The triple-configuration BDA, in contrast, cooled the stream, although the mean maximum stream temperature was the highest below these structures. Ponding upstream of BDAs increased discharge and resulted in cooling of the stream. Rainfall events sharply and transiently reduced stream temperatures, leading to a three-way interaction between BDA configuration, rainfall and stream discharge as factors co-influencing the stream temperature regime. Our results have implications for optimal growth of regionally important and threatened bull and cutthroat trout fish species.

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Abundance and Altitudinal Distribution of Ephemeroptera in a Rocky Mountain Stream

Advances in Ephemeroptera Biology ◽

10.1007/978-1-4613-3066-0_14 ◽

1980 ◽

pp. 169-177 ◽

Cited By ~ 14

Author(s):

James V. Ward ◽

Lewis Berner

Keyword(s):

Rocky Mountain ◽

Mountain Stream ◽

Altitudinal Distribution

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Integrated prestack depth migration of vertical seismic profile and surface seismic data from the Rocky Mountain Foothills of southern Alberta, Canada

Geophysics ◽

10.1190/1.1635031 ◽

2003 ◽

Vol 68 (6) ◽

pp. 1782-1791 ◽

Cited By ~ 1

Author(s):

M. Graziella Kirtland Grech ◽

Don C. Lawton ◽

Scott Cheadle

Keyword(s):

Seismic Data ◽

Rocky Mountain ◽

Velocity Model ◽

Seismic Profile ◽

Vertical Seismic Profile ◽

Prestack Depth Migration ◽

Data Set ◽

Depth Migration ◽

Southern Alberta ◽

Vsp Data

We have developed an anisotropic prestack depth migration code that can migrate either vertical seismic profile (VSP) or surface seismic data. We use this migration code in a new method for integrated VSP and surface seismic depth imaging. Instead of splicing the VSP image into the section derived from surface seismic data, we use the same migration algorithm and a single velocity model to migrate both data sets to a common output grid. We then scale and sum the two images to yield one integrated depth‐migrated section. After testing this method on synthetic surface seismic and VSP data, we applied it to field data from a 2D surface seismic line and a multioffset VSP from the Rocky Mountain Foothills of southern Alberta, Canada. Our results show that the resulting integrated image exhibits significant improvement over that obtained from (a) the migration of either data set alone or (b) the conventional splicing approach. The integrated image uses the broader frequency bandwidth of the VSP data to provide higher vertical resolution than the migration of the surface seismic data. The integrated image also shows enhanced structural detail, since no part of the surface seismic section is eliminated, and good event continuity through the use of a single migration–velocity model, obtained by an integrated interpretation of borehole and surface seismic data. This enhanced migrated image enabled us to perform a more robust interpretation with good well ties.

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