Albert Ruhi Vidal, Professor

Closed (1) Effects of climate change on Sierra Nevada stream food webs

Applications for fall 2021 are now closed for this project.

We investigate how extreme low flows that will be common due to climate change in the future alter aquatic insect communities of Sierra Nevada headwaters near Kings Canyon National Park. Future Sierra Nevada snowmelt is predicted to occur up to two months earlier in the year, which may result in lower summer flows, shifts in insect emergence timing, and changes in community structure. We sampled a watershed in the rain-snow transition zone to determine what aspect of low flow (e.g. reduced current, sedimentation, and increased temperature) has the greatest impact on native aquatic insects. We also will determine how species interactions may differ with low flow conditions and the relative influence of the upstream community. This experiment will improve our understanding of how climate change may alter stream communities as temperatures rise and precipitation shifts from snow to rain.

The URAP student will assist in sorting and identifying macroinvertebrates most weeks of the semester. This will require availability of two 3-4 hour shifts to complete a sample with a partner most weeks. This time should be available in your schedule. The student will be trained in identifying and sorting aquatic insects at the beginning of the semester. We welcome undergraduates to join Ruhi Lab meetings and learn more about our research if they desire to. We will provide personal development opportunities like learning how to manage data and apply for graduate school. The student will also have the opportunity to continue working on the project and pursue his or her own research question in the future, provided their work is satisfactory. Co-authorship is possible with a significant contribution to the project that can be discussed. Fieldwork is possible with this project or others in the lab if interested!

Day-to-day supervisor for this project: Kyle Leathers, Graduate Student

Qualifications: No prior experience is required, but skills or coursework in aquatic ecology, entomology, and microscope identification of samples are advantageous and should be mentioned in the application. The URAP student should be excited to learn about freshwater ecology and collaborate with our lab team. The student must have 2-3 days that they can devote 8 hours total time to sorting work. The student should highlight why they want to work with this project, how it matches their interests, and how it would help them reach their goals with aspects of their background used as supporting information throughout.

Weekly Hours: 6-8 hrs

Related website: https://nature.berkeley.edu/ruhilab/
Related website: https://www.youtube.com/watch?v=j9kobU_JKS4

Closed (2) Experiment on stream invertebrate dispersal in Pinnacles National Park

Applications for fall 2021 are now closed for this project.

We will survey aquatic invertebrate communities in the Chalone Creek basin (Pinnacles National Park), an intermittent stream network that exhibits clear gradients in drought severity and habitat fragmentation. In particular, we will develop a dispersal experiment to parse out the relative importance of different resistance and resilience mechanisms that allow stream biodiversity to persist in the face of drought.

Assist in the design, construction, and testing of invertebrate traps. This component will take place locally, in the Ruhi lab and in Strawberry Creek. Additionally, assist in the field during the development of the experiment (week to be determined based on rain conditions; likely between November-December). This field component will take place in Pinnacles National Park, and will involve assisting the PI in the deployment and maintenance of traps, and collecting aquatic invertebrates.

Day-to-day supervisor for this project: ALBERT RUHI

Qualifications: No prior experience is required, but skills or coursework in aquatic ecology, engineering, entomology, hydrology, or field research techniques are advantageous and should be mentioned in the application. The URAP student should be excited to learn about freshwater ecology and collaborate with our lab team.

Weekly Hours: to be negotiated

Off-Campus Research Site: Trips to Pinnacles National Park will be necessary when assembling the system and performing the experiment. Accommodation will be provided.

Related website: https://nature.berkeley.edu/ruhilab/
Related website: http://ciwr.ucanr.edu/CIWR_Making_a_difference/Towards_a_mechanistic_understanding_of_the_multi-scale_effects_of_drought_on_riverine_biodiversity/

Closed (3) Influence of tidal marsh restoration on aquatic food webs of the Sacramento–San Joaquin River Delta

Applications for fall 2021 are now closed for this project.

In the past decade, multiple projects in the upper San Francisco Bay Estuary and Delta have restored wetland habitat by breaching the wetlands and restoring their natural tidal connection with the estuary. However, effects of these restoration efforts at the food-web level remain largely unknown. The goal of this project is to evaluate whether the restoration of tidal wetlands translates into recovery of both community structure (species presence) and the dominant energy pathways (algal and detrital) connecting resources and consumers across the estuary-marsh continuum. This is a three-year project funded through Proposition 1 (California Department of Fish and Wildlife) and co-led by three institutions: UC Berkeley, USGS, and ICF. At UC Berkeley, PhD student Megan Pagliaro is leading the stable isotope analysis (SIA) component of the project. This component aims at determining the relative importance of imported vs. localized inputs in reference wetlands compared to restored (breached) wetlands, and interactions among the main groups of consumers. We will use three stable isotopes: carbon (to assess the carbon source), nitrogen (to determine trophic position), and sulfur (to track marine influence), and we will combine these data with community composition data. The results of this project will provide valuable information on the effect of restoration on wetland ecosystem recovery, and will inform future restoration and management strategies in the Delta. The project will continue beyond the scope of this position. Thus, opportunities will be available for undergraduates to get involved in the longer term, and develop independent research projects in the lab.

Separate, clean, and identify samples consisting of terrestrial and aquatic plants and aquatic macroinvertebrates. Assist in fish muscle dissections. Prepare samples for stable isotope analysis (e.g., drying, weighing on a microbalance, grinding) while in a sterile work environment. Potentially learn and assist in methods for isolating food-web components (e.g. phytoplankton, zooplankton, suspended organic matter, fine particulate organic matter).

Day-to-day supervisor for this project: Megan Pagliaro, Ph.D. candidate

Qualifications: While not required, a background in any the following is preferred and should be mentioned on the application: previous lab experience, relevant courses in environmental science and biology, majoring or minoring in a field relevant to the project, and any hands-on experience in field ecology and/or aquatic ecology. The student should be excited to learn more about wetland ecology and aquatic ecology. Ideally, students should be able to commit to working 6 hours per week, but we are willing to negotiate hours.

Weekly Hours: 6-8 hrs

Related website: https://nature.berkeley.edu/ruhilab/

Closed (4) The Potential for Wastewater Effluent to Restore Coastal Stream Ecosystems in Southern California

Applications for fall 2021 are now closed for this project.

Hydrologic connectivity is a major driver of river ecosystem structure and dynamics — from headwaters to estuaries. In Southern California, management agencies are currently making decisions that will affect hydrologic connectivity levels of local rivers for decades to come. However, we do not have a clear understanding of how such changes in flow levels may influence ecosystem health, access to biodiverse waterways, and the potential for restoring urban coastal rivers in the region. Several key decisions involve treated wastewater (effluent), which has dominated the flows of the Los Angeles and Santa Clara Rivers since the mid-to-late 20th Century. The steady addition of effluent has created new habitats that support a diversity of terrestrial and aquatic species, while also “perennializing” these historically intermittent waterways, causing them to reach the ocean more regularly. Sanitation districts are planning to recycle more treated wastewater to fortify local water supplies against drought, meaning there could be dramatically less effluent discharged into these rivers as soon as 2022. As a result, additional segments of these waterways will likely run dry during at least part of the year, reducing the degree of hydrologic and ecological connectivity within rivers and between riverine and estuarine ecosystems, and altering the structure and composition of their biological communities. I am conducting the first study of the consequences of these actions on the Los Angeles and Santa Clara Rivers, helping inform and improve decision-making and delivering products that advance our understanding of riverine ecosystems and how effluent can be a tool to restore ecosystem health and improve human well-being.

Sort and identify terrestrial and aquatic invertebrates.

Day-to-day supervisor for this project: Melissa von Mayrhauser, Graduate Student

Qualifications: The student is not required to have previous invertebrate identification experience, but a background in environmental science, previous hands-on fieldwork experience, and an interest in freshwater ecology are desired.

Weekly Hours: 6-8 hrs

Related website: https://nature.berkeley.edu/ruhilab/