Aya Reiss

Department of Forest Sciences
3041-2424 Main Mall, UBC
Vancouver, B.C. V6T 1Z4
Email: areiss@interchange.ubc.ca
Position: M.Sc. Candidate

Study Area: Tracing the impacts of logging fishless headwaters on downstream fish populations.

The value of riparian forests to invertebrate and fish populations in adjacent streams has been recognized for a) leaf litter and woody debris contribution – a source of food and habitat, b) bank stability – influencing sediment input, and c) canopy cover – affecting both water temperature and shade. Riparian tree species influence the abundance and diversity of both aquatic and terrestrial insects found in streams. Cutthroat trout (Oncorhynchus clarki) are primarily drift-feeding organisms consuming both types of insects as food sources. Prey exported from fishless headwaters have the potential to boost growth and viability of downstream trout populations. Logging of forests alters riparian canopy and has subsequent impacts on the riparian ecosystem.

My research will investigate the seasonal variation in invertebrate subsidies from headwaters under different forest management regimes to fish-bearing reaches. Further, it will assess the extent to which variation in drift influences cutthroat trout. Through a comparative study of invertebrate and organic matter exports from headwater streams bordering mature alder (Alnus rubra) and coniferous (Tsuga heterophylla, Thuja plicata, Pseudotsuga menziesii) forests, I will develop a food resource energy budget for fishless headwaters in the temperate rainforests of British Columbia. Further, by manipulating available drifting food resources to trout populations, I will determine growth response as a factor of drift quantity. Linking this response to energy budgets in the stream will allow me to assess the biological response of trout to headwater harvesting. Fishless headwater streams have the potential to contribute a significant portion of the cutthroat trout diet. Establishing a firm connection between fish fitness and headwater subsidies will provide a foundation for management of these currently unprotected areas.

Interests: A native of Washington State, I completed my Bachelor’s degree in Biology at Williams College in Massachusetts. In the five years since completing my degree, I have taught high school and worked on various conservation research projects in Hawaii. As a high school teacher, I taught environmental science to grade 11 at a small school in Vermont. The two years I spent in Hawaii were divided between work on a project with the USGS Palila Restoration Project and a Koa forestry project with Stanford University. I’ve summered as a sea kayak guide in the San Juan Islands for the past three summers. Other interests include bird-watching, cross-country skiing and traditional artisan baking.