Spring Rivers and Streams

Coldwater fish species such as coho salmon and rainbow trout are increasingly threatened as climate changes and temperatures rise. They must adapt, migrate or face extinction. But freshwater fish can only migrate so far; they are bound by river corridors, barriers and physical conditions (salt water tolerance, temperature, etc.).

Spring-fed rivers and streams are becoming more important for cold-water fish species because the water volume and temperatures in these systems are more resilient to variation in precipitation and climate change than surface run-off watersheds. Spring-fed rivers will act as cold-water refuges for these species as climate changes and surface water-fed rivers run low and warm.

The underlying geology of a river is one of the most important factors in determining whether a watershed will be more resilient to climate change by maintaining cold water for cold-water species. Water chemistry is another factor that contributes to ecological productivity, particularly in a spring-fed system. Underlying rocks can contain nutrients such as nitrogen and phosphorous, common nutrients in spring waters and critical for a robust aquatic food-web (Jeffres et al. 2009).

The UC Davis Center for Watershed Sciences has taken a multi-disciplinary approach to studying spring-fed systems. Spring-fed systems are a prime example of physical conditions driving the aquatic biota, and as such provide a unique opportunity for a synergism between various research groups. Areas of research include: geology, geomorphology, water quality, hydrology, vegetation, invertebrates and fish. By researching all of these areas, a complete story of spring-fed systems can be assembled.

Research Programs

Spring Rivers and Streams
	Project
	Migration of Fall River rainbow trout	The purpose of this study is to better understand the spawning migration and timing of rainbow trout in the spring-fed Fall River of Northern California.
	Scott River	The Scott River includes California's largest wild population of coho salmon (Onchorhynchus kisutch); a species listed as threatened under both state and federal Endangered Species Acts. The Center for Watershed Sciences is partnered with California Trout and Western Rivers Conservancy to improve conservation strategies within the Scott River and its coldwater tributaries while maintaining agricultural land-use activities for private property-owners in the region. Monitoring throughout this watershed is focused on determining whether current conditions meet desirable streamflow and water temperature criteria for the success of the species and whether ongoing conservation activities have any positive effect on these conditions.
	Spring-Fed vs. Snowmelt Rivers: Ecosystem Productivity	This project measures and compares ecological productivity in two types of river systems in the Upper Sacramento River watershed. The project's team of ecologists, geologist and biologists is comparing the food-web dynamics of three spring-fed systems - Hat Creek, Fall River and tributaries of the upper Sacramento River - with those of rivers that receive mainly snowmelt and stormwater runoff in the same watershed.
	Big Springs Creek	In 2008, Center researchers seized a rare opportunity to quantify the results of conservation action on a large scale. The Nature Conservancy bought ranchland along Big Springs Creek, a Shasta River tributary that had been degraded by cattle grazing. The conservancy continued ranching but fenced out cattle along the 2.2 mile stream.
	Little Shasta River	The Little Shasta River project is the third phase of CWS’ research in the Shasta basin – moving past baseline assessment and demonstration projects to private landowner collaboration. The Center for Watershed Sciences is partnering with private landowners, California Trout, and The Nature Conservancy to identify how heritage rangeland can be managed to ensure the long-term viability of both rangeland and recover coho salmon populations. Our research shows how science can inform and influence the management of rangeland and environmental resources.