Estuary Monitoring

Posted December, 2016
New Study Released:

Winter Distributions, Movements, and Habitat use by Juvenile Salmonids throughout the Lower Smith River Basin and Estuary, Del Norte County, California

Properly functioning estuaries are complex systems where aquatic organisms benefit from a variety of spatial and temporal niches. This is especially evident for Pacific juvenile salmonids, where studies have shown estuarine habitats can be more productive and can lead to greater growth and survival compared to those derived from natal stream habitats occurring upstream. Habitats including low gradient streams, sloughs, backwaters, off channel ponds, and emergent tidal wetlands have been shown to be especially productive features for rearing juvenile salmon throughout California and the Pacific Northwest. Understanding the functional role of coastal streams and estuaries can aid management and restoration decisions in maximizing population resilience through protection of diverse life-history patterns expressed among various salmonid populations.

This study adds a second winter period to a two-year comprehensive fish and habitat inventory of the lower Smith River and its estuary. From January 7 to March 19, 2016 we surveyed a total of 200 winter salmonid rearing habitat across 35.9 km using minnow traps, beach seines, and snorkel surveys. We also evaluated migration timing and residence in coastal streams by utilizing PIT tag antennas located in Morrison Creek and Tryon Creek. We found coho salmon to be widely distributed throughout coast tributaries that are dry during some of the summer months. Our findings can help to guide restoration efforts to maximize the survival of estuarine rearing individuals and aid in the recovery and conservation of salmonids in the Smith River basin.

Posted June, 2015
2015 Study

Distribution of Juvenile Salmonids and Seasonally Available Aquatic Habitats within the Lower Smith River Basin and Estuary – August 2015

Studies have suggested that estuaries, sloughs, backwaters, off channel ponds, and beaver structures are productive habitat features for rearing juvenile coho salmon throughout the Pacific Northwest. Little is known about the degree to which habitat features are available and used by rearing coho salmon in the lower Smith River. This project was the first year of our efforts to identify, map, and monitor juvenile coho distribution and habitat in the main channel, sloughs, beaver sites, alcoves, backwaters, and tributaries within the lower Smith River. Results offer essential baseline information to aid in restoration efforts.