Life Sciences Commons^™

The Macroinvertebrate And Fish Communities Of In-Stream Beaver Ponds In Northeastern Utah, Susan Washko

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Beavers were virtually extirpated from North America during the fur trade, but populations have since recovered. Dams built by recolonizing beaver alter stream habitat by forming deep, slow ponds within the streams. Such changes to the habitat is likely to have consequences for organisms such as macroinvertebrates and fish. The objective of this study was to identify the differences in the macroinvertebrate and trout community in beaver ponds and lotic (e.g. flowing reaches of a stream) reaches in tributaries to the Logan River in northeastern Utah. The macroinvertebrate community of beaver ponds had fewer species, fewer numbers, and lower biomass …

Using Network Models To Predict Steelhead Abundance, Middle Fork John Day, Or, Monica R. Blanchard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

It is important in the management of threatened and endangered species to have informed population estimates. Population estimates are used to gage whether or not recovery goals are being met. When assessing Pacific salmonids this assessment involves sampling a small subset of the population and then scaling up to estimate larger populations units. This is complicated by the fact that fish populations are not evenly distributed along river systems but respond to fluctuating physical and biological stream properties. We used rapid assessment survey methods and the River Styles classification to explore fish-habitat relationships. River Styles is a classification system that …

Approaches For Studying Fish Production: Do River And Lake Researchers Have Different Perspectives? – Extended Abstract, Wayne A. Wurtsbaugh, Nicholas A. Heredia, Brian G. Laub, Christy S. Meredith, Harrison E. Mohn, Sarah E. Null, David A. Pluth, Brett B. Roper, W. Carl Saunders, David King Stevens, Richard H. Walker, Kit Wheeler

Watershed Sciences Faculty Publications

Biased perspectives of fisheries researchers may hinder scientific progress and effective management if limiting factors controlling productivity go unrecognized. We investigated whether river and lake researchers used different approaches when studying salmonid production and whether any differences were ecologically supported. We assessed 564 peer‐reviewed papers published between 1966 and 2012 that studied salmonid production or surrogate variables (e.g., abundance, growth, biomass, population) and classified them into five major predictor variable categories: physical habitat, fertility (i.e., nutrients, bottom‐up), biotic, temperature, and pollution. The review demonstrated that river researchers primarily analyzed physical habitat (65% of studies) and lake researchers primarily analyzed fertility …

Pervasive Thermal Consequences Of Stream-Lake Interactions In Small Rocky Mountain Watersheds, Usa, Jessica D. Garrett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Limnologists and stream ecologists acknowledge the fundamental importance of temperature for regulating many ecological, biological, chemical, and physical processes. I investigated how water temperatures were affected by hydrologic linkages between streams and lakes at various positions along surface water networks throughout several headwater basins in the Sawtooth and White Cloud Mountains of Idaho (USA). Temperatures of streams and lakes were measured for up to 27 months in seven 6 – 41 km² watersheds, with a range of lake influence. When they were ice-free, warming in lakes resulted in dramatically warmer temperatures at lake outflows compared to inflow streams (midsummer …

Differences In Nitrate Uptakeamong Benthic Algal Assemblages In A Mountain Stream, Michelle A. Baker, G. De Guzman

Biology Faculty Publications

We evaluated how benthic algal assemblages that vary in composition, richness, and other diversity metrics remove NO 3 -N from the water column of a mountain stream. Ecological theory and empirical studies suggest that ecosystem process rates should increase as richness increases because of niche separation or activity of dominant taxa. Accordingly, we predicted that algal assemblages with highest richness would show the highest rates of NO 3 -N uptake. To test this prediction, we transplanted 225 rocks representing 3 patch types (green, yellow, and brown) that differed macroscopically in algal composition from a lake outflow stream to a lake …

Discontinuities In Stream Nutrient Uptake Below Lakesin Mountain Drainage Networks, Michelle A. Baker

Michelle A. Baker

In many watersheds, lakes and streams are hydrologically linked in spatial patterns that influence material transport and retention. We hypothesized that lakes affect stream nutrient cycling via modifications to stream hydrogeomorphology, source‐waters, and biological communities. We tested this hypothesis in a lake district of the Sawtooth Mountains, Idaho. Uptake of NO3− and PO4−3 was compared among 25 reaches representing the following landscape positions: lake inlets and outlets, reaches >1‐km downstream from lakes, and reference reaches with no nearby lakes. We quantified landscape‐scale hydrographic and reach‐scale hydrogeomorphic, source‐water, and biological variables to characterize these landscape positions and analyze relationships to nutrient …

Nitrogen Transport Through Linked Stream-Lake Systems Measured With N Tracer, Wayne A. Wurtsbaugh, Koren Nydick, Michelle A. Baker, Bob Hall

Watershed Sciences Faculty Publications

No abstract provided.

Topo-Morphometric Analysis Of Lake-Stream Interactions In Alpine Watersheds, Wayne A. Wurtsbaugh, Michelle A. Baker

Watershed Sciences Faculty Publications

No abstract provided.

The Effects Of Salmon Availability, Social Dynamics, And People On Black Bear (Ursus Americanus) Fishing Behavior On An Alaskan Salmon Stream, Danielle K. Chi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The primary goals of this research were to investigate 3 ecological factors influencing black bear (Ursus americanus) foraging behavior on an Alaskan salmon (Oncorhynchus spp.) stream: fish availability, social dynamics, and human activity. Over 900 observation hours were logged at 2 falls from July 1-September 1 1993-1995; the lower falls were open to public for wildlife viewing, but the upper falls were restricted to research personnel.

In general, black bears responded to differences in fish accessibility on both spatial and temporal scales. All years of the study, 3 indices of bear activity (bear minutes, bear numbers, bout …

Stream Insect Production As A Function Of Alkalinity And Detritus Processing, Thomas G. Osborn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The study was conducted to determine if aquatic insect production was significantly different between high and low alkalinity mountain streams and if any differences were associated with food availability factors. The major objectives included determining: (1) if annual production differences occur between high and low alkalinity streams; (2) if processing rates of terrestrial detritus differs between high and low alkalinity streams; (3) if detrital processing rates are related to stream insect productivities; (4) if primary productivity varies between high and low alkalinity streams; (5) if toxic effects or micronutrient limitations exist in high or low alkalinity streams that could limit …