Niche and Habitat: Salmon and Steelhead

WFC 10 15 October 2008

Lisa Thompson

Fisheries Extension Specialist Wildlife, Fish, & Conservation Biology Department

University of California, Davis

Outline

• “Niche and habitat change with the life stage of the organism.”

• Salmon life history • Salmon life stages

– Habitat – Niche – Conservation issues

Definitions • Habitat

– Distribution – Actual location in the environment where the

organism lives • Niche

– Role of organism in community • Fundamental Niche

– Based on physical and chemical habitat, and food availability

• Realized Niche – Also includes interactions with predators and

competitors

Salmon and Steelhead

Chinook salmon

Steelhead / Rainbow Trout

Coho salmon

Spawners

Egg

Alevin

Fry

Parr Smolt

Adult

OCEAN

FRESHWATER

ESTUARY

ESTUARY

Salmonid Life Cycle

Watersheds in Northern California

Map courtesy of the Water Education Foundation

Federal project

Local project Wild & scenic Natural lake, river Saline / alkaline

lake Irrigated area

Urbanized area

Pumping or power plant

State project

• What is the fish trying to do? – Survive – Grow – Reproduce

• Why do habitat and niche change with life stage?

Egg

~ 1 cm 3/8”

Habitat Egg Life Stage

Redd

Photo by Jenna Voss

Irrigation Diversion – Cow Creek

Water Temperature

Species Water Temperature (°F)

Migration Spawning Incubation Juvenile Rearing

Preferred Optimum Lethal

Chinook (Fall run)

51.1-66.9 42.1-57.0 41.0-57.9 45.1-58.3 54.0 77.4

Chum 46.9-60.1 45.0-55.0 39.9-55.9 52.2-58.3 56.3 78.4

Coho 45.0-60.1 39.9-48.9 39.9-55.9 53.2-58.3 --- 78.4

Steelhead --- 39.0-48.9 --- 45.1-58.3 50.0 75.4

Source: Adapted from Beschta et al. (1987) Note: °C = (°F-32)/1.8

Bank Erosion & Siltation

Dissolved Oxygen

Response DO (ppm)

Percent Oxygen Saturation at Given Temperatures

Water Temperature (°F) 32 41 50 59 68 77

Function without impairment

7.75 76 76 76 76 85 93

Initial distress symptoms 6.00 57 57 57 59 65 72

Most fish affected by lack of oxygen

4.25 38 38 38 42 46 51

Adapted from Bjornn & Reiser (1991) Note: Less oxygen can be dissolved in warm water than in cold water. Therefore the same amount of DO results in a higher percent saturation at higher temperatures.

Alevin

~ 3 cm 1”

Photo by Marj Trim

Habitat Alevin Life Stage

Fry

~ 4 cm 1 ½”

Photo by Gerard Carmona Catot

Habitat Fry Life Stage

Shallow Edge Habitat

Bank Erosion & Siltation

Parr

~ 9 cm 3”

Photo by Jenna Voss

Habitat Parr Life Stage

Parr foraging in deeper water

Photo by Jenna Voss

Chinook salmon parr foraging

• http://youtube.com/watch?v=xRgSSQcxL08 • There are both Chinook salmon and

Sacramento suckers in this video clip • Chinook have parr marks – a row of about 10

spots along the side of the body • Suckers have 2 or 3 round gray spots on the

side

Steelhead/Rainbow Trout & Large Wood

Steelhead/Rainbow Trout & Large Wood

Photo by Jenna Voss

Steelhead/Rainbow Trout & Large Wood

Photo by Jenna Voss

Loss of large wood and pools Gualala River

Exotic species – Brook trout

Rainbow trout

Brook trout

Photo by Gerard Carmona Catot

Coho Salmon Smolt

~ 15 cm 6”

Habitat Smolt Life Stage

River & Estuary Habitat Santa Clara River Estuary

Suisun Marsh

Diversions = Detours

Map courtesy of the Water Education Foundation

Federal project

Local project Wild & scenic Natural lake, river Saline / alkaline

lake Irrigated area

Urbanized area

Pumping or power plant

State project

Rip-rapped bank Lower American River

Habitat Adult Life Stage

Santa Clara River Estuary & Ocean

Spring-run Chinook Salmon Spawners

~ 0.75 m 2 ½ ’

Habitat Spawner Life Stage

Chinook Salmon Spawner Migrating

Redd

Photo by Jenna Voss

Butte Creek Chinook salmon spawning

• http://www.youtube.com/watch?v=A8vPcOv3E0g&NR=1 • The female is the smaller, more green-colored fish • The males are larger, and more red-colored

Dams & Barriers are Roadblocks to Fish

Shasta Dam, 1945, Central Valley Project. Dams & water diversions block fish movement to

headwaters of Central Valley streams

Dead spawner adding nutrients to stream

Salmon & Steelhead Life Histories

Chinook Coho Steelhead Years in Stream 0 - 1 1 1 - 3

Years in Ocean 1 - 7 2 1 - 4

Spawner Age 4 3 2 – 7 (may spawn

more than once)

Adult Size Up to 100 lb. 7-12 lb. Up to 27 lb.

Eggs per Female

5,000–12,000 2,000 – 5,000 200 – 12,000

More information on California fish life histories…

• http://www.calfish.ucdavis.edu/