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Home , Chinook salmon, Rainbow trout, Salmon run

Understanding Napa County Watersheds Steelhead and Understanding Napa County Watersheds Indicators of Watershed Health Steelhead and Salmon Steelhead & Salmon A watershed’s ecological health is directly reflected by the condition Steelhead and salmon are anadromous , meaning they are born in Requirements of its salmonid populations. Migratory fish, including steelhead and freshwater, migrate to the , and return to freshwater as adults to salmon, are indicator , meaning they are highly sensitive to . The Napa and many streams in Napa County historically environmental disturbance such as habitat alteration and pollution, supported large numbers of steelhead , , and coho and therefore, provide an early warning sign of ecosystem salmon. Unfortunately, their populations have declined sharply in the deterioration. Reductions in water quantity, poor water quality from past several decades. became extinct in the pollution and , and habitat degradation all have direct,

Watershed in the 1960s and steelhead were listed as threatened in Napa ToddAdams negative impacts on salmonids. County in 1997 under the Act. A small chinook A large, diverse population indicates a healthy watershed system still exists in the Napa River, but it is not clear whether these Adult Migration while low numbers are indicative of overall habitat degradation. are wild fish or strays from in the Sacramento and San Joaquin Adult female chinook salmon, Napa Creek, 2003 · Adequate stream temperatures The diminishing salmonid populations in Napa County reflect how River systems. Improving and expanding habitat for steelhead and (55° - 70° F) aquatic systems have been altered over the past century. chinook salmon is a top priority in the Napa River Watershed. · Moderate flow velocities Did You Know? · Lack of impassable barriers such as Steelhead Trout mykiss Chinook salmon, coho salmon, road culverts, crossings, and dams Protection Efforts · Adequate water clarity and steelhead trout belong to the Many groups and individuals are actively involved in efforts to Steelhead and are the same family . Fish in this · Habitat complexity with holding areas ensure the survival of Napa County’s remaining steelhead and species; only their life history pattern and shelter family are called salmonids. salmon populations. These efforts include monitoring fish distinguishes one from the other. · Hiding cover from predators abundance and distribution, improving the condition of existing Steelhead migrate to the ocean and rainbow They also belong to the Spawning fish habitat, expanding habitat through stream restoration and trout remain in freshwater their entire life. Interestingly, both can come Oncorhynchus, which means “hooked snout”. The name refers · Clean, un-silted gravel (1-4 inches in barrier removal, and educating the public about the importance of from the same parents, regardless of their life-history, and most to the elongated hooked snout diameter) protecting these vanishing species. The goal is to improve and populations contain a mix of anadromous and resident fish. · Adequate, sustained streamflow spawning salmon males develop. restore fish populations to self-sustaining levels through habitat Adult steelhead have a blue to nearly brown iridescent back, silver sides, · Cold water temperatures (55° to 70° F) Chinook salmon are the largest improvement, land stewardship, and education. an iridescent pink to red lateral band, pinkish cheeks, a silver, white, or · Complex channel habitat: pools, , of any salmon. Spawning adults yellowish belly, and numerous black spots on the tail, adipose fin, dorsal riparian trees, large logs The RCD is actively engaged in this effort. To find out how, visit often exceed 40 pounds. The · Gravel bed not subject to scour or www.naparcd.org or contact Jonathan Koehler, RCD Senior fin, and back. largest on record for siltation Biologist, at (707) 252-4188 ext. 109. Steelhead populations in Napa County have been greatly reduced from weighed just over 84 pounds. Incubation/Emergence historical levels of approximately 8,000 adults as recently as 100 years The Napa River basin has been Sources · Clean, well-aerated gravel ago. The population is currently estimated to be between 200 and 1,000 identified as San Francisco Dewberry, Dr. T. C. of Ecotrust and Friends of the Napa River. 2001. Whole-basin · Sustained cold streamflow adult fish, but is not well known. Steelhead spawning has been Bay’s most significant direct · Lack of excessive channel scour and Snorkel Count for Steelhead Trout in the Napa Watershed, California (Year 2001) - Final Report. documented consistently in many tributaries each year, and most streams tributary with the highest siltation appear to be well-seeded with juvenile steelhead. potential for maintaining and · Complex channel habitat: pools, riffles, Jonathan Koehler, Senior Biologist, Napa County Resource Conservation District . restoring current and historical riparian trees, large logs Leidy, Robert A., Gordon Becker, and Brett Harvey. 2003. Historical Distribution and Chinook Salmon Oncorhynchus tshawytscha salmonid populations. Current Status of Steelhead, Coho Salmon, and Chinook Salmon in Streams of the San Juvenile Rearing Francisco , California. www.cemar.org/pdf/solano.pdf. Chinook salmon (also known as king · Cool summer water temperatures Moyle, Peter B. 2002. Inland of California. Berkeley, CA: University of salmon) in the Napa River Watershed are a fall run species, meaning they (< 70° F) begin to migrate from the ocean to their freshwater spawning grounds in · Habitat for feeding and refuge: pools, California Press. the fall. While at sea, chinook have blue-green backs and silver flanks, but riffles, riparian trees, large logs Napa County Resource Conservation District. 1994. Napa River Watershed Owner’s · Good water quality Manual: An Integrated Resource Management Plan. A collection of natural resource as they reach spawning age they become olive brown to dark maroon and · Sustained cold streamflow management recommendations developed by the RCD with assistance from private develop conspicuous streaking or blotches on their sides and numerous black spots on their back, , · Hiding cover from predators citizens, local interest groups, and federal, state, and local government agencies. and tail. Spawning males are darker than females and have hooked jaws and slightly humped backs. Purchase it at the RCD/NRCS office or view sections of it on the RCD’s website at Smolt Outmigration naparcd.org/ownermanual.htm. Chinook have been sporadically reported in the Napa River since the 1980s; however, until recently, no one had · Adequate streamflow in late spring NOAA National Marine Service. Chinook Salmon species account. collected information on how many there are or where they spawn. In the winters of 2003 and 2004, a · Hiding cover from predators www.nmfs.noaa.gov/pr/species/fish/Chinook_salmon.html. significant number of spawning chinook returned to the Napa River basin. Field surveys along a 3.5 mile · Cool water temperature and adequate stretch of the Napa River conducted by the Napa County Resource Conservation District (RCD) in the winter water quality This fact sheet was prepared by the Napa County Resource Conservation District of 2004 documented 62 spawning nests and over 100 spawning adults. The surveys also showed that some of · Lack of barriers or low-flow obtacles with assistance from the Natural Resources Conservation Service and funded through Napa County’s Watershed Education Program coordinated by the Conservation Division the fish were strays from fish hatcheries in the Central Valley. Regardless of their origin, it is possible that a of the Napa County Conservation, Development and Planning Department. self-sustaining population of chinook salmon is developing in the Napa River.

Napa County Resource Conservation District 4 Napa County Resource Conservation District 1 Understanding Napa County Watersheds Steelhead and Salmon

The unique life cycle of steelhead and salmon poses challenges for protection efforts. Their populations are controlled by ecological conditions throughout the watershed, bay, and ocean. and Protecting inland waters is particularly important. and streams must provide the complex habitat conditions essential for spawning and rearing. Steelhead and salmon require The Steelhead Salmon Life Cycle clean water, adequate water flow, abundant food, and a well-functioning to thrive. If any of these requirements is absent or limited, their populations decline.

Migration into the Napa River begins in the fall Spawning chinook salmon in the Napa River Chinook salmon in the Napa River Chinook salmon alevin and eggs Chinook salmon parr from the Napa River Migration out of the Napa River begins in the spring Adult Migration Spawning Incubation Emergence Juvenile Rearing Smolting Spawning chinook Adult chinook salmon move into the salmon Once the adults The eggs will remain in the gravel for After the eggs hatch, the tiny Young fry tend to As the young fish Napa River immediately following the reach their one to three months, depending upon Chinook fish remain buried in the congregate in schools move downstream salmon alevin Chinook Chinook first rains in fall, returning to the male natal stream or environmental conditions. They are a gravel, nourished by an salmon parr around cover along banks salmon smolt they undergo same streams where they were born. other suitable site, translucent yellow to orange color and attached yolk sac for two to and under logs. As they grow older and physiological changes that Adult steelhead follow salmon into the female the female chooses a nest are relatively large (1/6 to 1/3 of an three weeks. At this stage the fish larger, fry become parr with distinct allow them to live in saltwater. basin arriving in late fall/early winter. site, called a redd, in gravel and inch). are called alevins. markings and begin to find and defend During this phase, the builds it by fanning her tail (caudal They find their way back to the Napa The eggs cannot develop without Once the yolk sac is absorbed, the small territories within the stream. lose their parr marks and turn a fin), thus creating a depression where River Watershed by “remembering” well-aerated, cold, clean water. The eggs fish emerge from the gravel and move During their stay in freshwater, they silvery color. This process is known the eggs will be deposited and incubate. smells, visual cues, and other unique are highly sensitive to fine sediment and into the calm stream margins to begin feed mostly on aquatic insects and as smoltification and the fish are stream characteristics they During spawning, the female deposits other pollutants, which can clog the feeding and growing. The fish are now require clean, cool water and good now called smolts. encountered during their seaward the eggs into the downstream portion spaces between the gravel and reduce called fry. They are very small and are quality habitat to survive. Generally, smolts reach the lower migration as juveniles. of the depression and simultaneously the amount of water flowing over the easy prey for other fish, birds, During Napa’s hot dry summer, juvenile portion of a river system in several the male releases to fertilize the and other . days or weeks. Some will stay in the Typically, once they enter fresh eggs. steelhead are typically found in deeper, eggs. estuary to grow, while others simply water from the sea, they don’t eat. A constant flow of freshwater is vital to To survive, the fry must find cover and well-shaded pools where they can hide head straight for the ocean. Young All their energy is focused on Adult chinook salmon die shortly after bring oxygen to the developing protection in the stream. Most often from predators and move into fast- chinook salmon smolt at a very small migrating upstream to suitable spawning; however, steelhead may embryos and carry away waste. Too this protection comes in the form of moving riffles to actively feed. size (2-3 inches), while steelhead spawing areas, engaging in courtship, return to the ocean and repeat the much silt, lack of flowing water, or undercut banks or beneath logs where Life in the river is difficult and most are smolts are typically older and larger nest building and spawning. spawning cycle in subsequent years. In increased water temperature will kill the there is low water velocity. Chinook eaten or die within the first year. Juvenile (5-6 inches). the Napa River watershed, chinook eggs. During incubation, eggs are salmon fry seek shelter in side channels steelhead spend one to three years in salmon are more likely to spawn in the vulnerable to scour caused and backwater areas; much of this freshwater, while chinook salmon spend main stem of the river while steelhead by high flows during storms. protective habitat has been lost in the just a few months in the stream and Fish illustrations courtesy of Ocean adult prefer smaller tributary streams. Napa River. move downstream to the estuary. the U.S. Fish & Wildlife Service chinook salmon Once salmon and steelhead reach the ocean, there is abundant food and growth is rapid. The first year of life in the ocean is the most critical year for the young salmon and steelhead, as Life in the Ocean there are many predators in the ocean that eat fish of their size. Chinook will spend 2-5 years, and steelhead 1-2 years, in the ocean before returning to the Napa River Watershed to spawn. A Year in the November December January February March April May June July August September October Adult migration Life of Spawning Steelhead Incubation Chinook Salmon

Emergence 123456789012345678901234567890121234567890123456789012345678901212345678901234567890123456789012123456789012 123456789012345678901234567890121234567890123456789012345678901212345678901234567890123456789012123456789012 and Salmon 123456789012345678901234567890121234567890123456789012345678901212345678901234567890123456789012123456789012 Juvenile rearing

in the Juvenile rearing in 12345678901 12345678901 Napa River lower Napa River estuary Smolting Watershed* Steelhead * There is tremendous variation within any given steelhead and salmon population. This chart represents a generalized description of their life history in the Napa River Watershed.

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