Steelhead and salmon distinct population segments facts for kids
The National Oceanic and Atmospheric Administration (NOAA), along with the U.S. Fish and Wildlife Service and the Environmental Protection Agency, works to protect important fish like steelhead and salmon. They group these fish into special categories called distinct population segments (DPS) for steelhead and evolutionarily significant units (ESU) for Pacific salmon. These groups help scientists and government agencies decide if a specific population of fish needs protection because it is threatened or endangered species under the Endangered Species Act. This means they are either at risk of becoming endangered or are in danger of disappearing completely.
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Steelhead Populations: What's a DPS?
Steelhead (Oncorhynchus mykiss) are a type of rainbow trout that spend part of their lives in the ocean before returning to freshwater to spawn. To protect them, scientists have identified 15 different "Distinct Population Segments" (DPS). A DPS is a group of animals that is separate from other groups of the same species and is important for the species as a whole. If a DPS is struggling, it can be listed as threatened or endangered.
Here's a look at some of the steelhead DPS groups and their current status:
| Steelhead Oncorhynchus mykiss | ||
|---|---|---|
| DPS Name | Initial/Revised Status | Current Status |
| Southern California DPS | Endangered (1997), (2006) | Endangered (2011) |
| South-Central California Coast DPS | Endangered (1997), Threatened (2006) | Threatened (2011) |
| California Central Valley DPS | Threatened (1998), (2006) | Threatened (2011) |
| Central California Coast DPS | Threatened (1998), (2006) | Threatened (2011) |
| Northern California DPS | Threatened (1998), (2006) | Threatened (2011) |
| Klamath Mountains Province DPS | ||
| Lower Columbia River DPS | Threatened (1998), (2006) | Threatened (2011) |
| Middle Columbia River DPS | Threatened (1999), (2006) | Threatened (2011) |
| Oregon Coast DPS | ||
| Puget Sound DPS | Threatened (1997) | Threatened (2011) |
| Olympic Peninsula DPS | ||
| Snake River Basin DPS | Threatened (1997), (2006) | Threatened (2011) |
| Southwest Washington DPS | ||
| Upper Columbia River DPS | Endangered (1997), Threatened (2006), Endangered (2007), Threatened (2009) | Threatened (2011) |
| Upper Willamette River DPS | Threatened (1999), (2006) | Threatened (2011) |
Pacific Salmon Populations: What's an ESU?
Pacific salmon (Oncorhynchus) include five main species: Chinook, Coho, Sockeye, Chum, and Pink salmon. For these species, scientists use "Evolutionarily Significant Units" (ESUs). An ESU is a group of organisms that is genetically different from other groups of the same species and is important for the species' long-term survival. There are 31 ESUs for Pacific salmon.
Chinook Salmon ESUs
Chinook salmon (Oncorhynchus tshawytscha) are the largest and often most prized salmon. Many of their populations are facing challenges.
| Chinook salmon Oncorhynchus tshawytscha | ||
|---|---|---|
| ESU Name | Initial/Revised Status | Current Status |
| Central Valley Spring-run ESU | Threatened (1995), (2005) | Threatened (2011) |
| Central Valley Fall-run and Late Fall-run ESU | ||
| California Coast ESU | Threatened (1999), (2005) including hatchery stocks |
Threatened (2011) |
| Oregon Coast ESU | ||
| Mid-Columbia River Spring-run ESU | ||
| Lower Columbia River ESU | Threatened (1999), (2005) | Threatened (2011) |
| Deschutes River Summer/Fall-run ESU | ||
| Southern Oregon & Northern California Coastal ESU | ||
| Snake River Spring/Summer-run ESU | Threatened (1992), (2005) | Threatened (2011) |
| Snake River Fall-run ESU | Threatened (1992), (2005) | Threatened (2011) |
| Sacramento River Winter-run ESU | Threatened (1989), (1990), Endangered (1992), Threatened (2004), Endangered (2005) |
Endangered (2011) |
| Puget Sound ESU | Threatened (1995), (2005) | Threatened (2001) |
| Washington Coast ESU | ||
| Upper Willamette River ESU | Threatened (1999), (2005) | Threatened (2011) |
| Upper Klamath-Trinity Rivers ESU | ||
| Upper Columbia River Summer/Fall-run ESU | ||
| Upper Columbia River Spring-run ESU | Endangered (1999), (2005) | Endangered (2011) |
Coho Salmon ESUs
Coho salmon (Oncorhynchus kisutch) are known for their silver sides and bright red meat. They are also an important part of the Pacific ecosystem.
| Coho salmon Oncorhynchus kisutch | ||
|---|---|---|
| ESU Name | Initial/Revised Status | Current Status |
| Central California Coast ESU | Endangered (1996), (2005) including hatchery stocks |
Endangered (2011) |
| Lower Columbia River ESU | Threatened (2005) | Threatened (2011) |
| Olympic Peninsula ESU | ||
| Oregon Coast ESU | ||
| Puget Sound/Strait of Georgia ESU | ||
| Southern Oregon/Northern California ESU | Threatened (1997), (2005) | Threatened (2011) |
| Southwest Washington ESU | ||
Sockeye Salmon ESUs
Sockeye salmon (Oncorhynchus nerka) are famous for turning bright red when they return to their spawning grounds.
| Sockeye salmon Oncorhynchus nerka | ||
|---|---|---|
| ESU Name | Initial/Revised Status | Current Status |
| Baker River ESU | ||
| Lake Pleasant ESU | ||
| Lake Wenatchee ESU | ||
| Okanogan River ESU | ||
| Ozette Lake ESU | Threatened (1999), (2005) | Threatened (2011) |
| Quniault Lake ESU | ||
| Snake River ESU | Endangered (1991), (2005) | Endangered (2011) |
Chum Salmon ESUs
Chum salmon (Oncorhynchus keta) are also known as dog salmon. They are important for many ecosystems.
| Chum salmon Oncorhynchus keta | ||
|---|---|---|
| ESU Name | Initial/Revised Status | Current Status |
| Columbia River ESU | Threatened (1999), (2005) | Threatened (2011) |
| Hood Canal Summer-run ESU | Threatened (1995), (2005) | Threatened (2001) |
| Pacific Coast ESU | ||
| Puget Sound/Strait of Georgia ESU | ||
Pink Salmon ESUs
Pink salmon (Oncorhynchus gorbuscha) are the smallest and most common Pacific salmon. They have a unique two-year life cycle.
| Pink salmon Oncorhynchus gorbuscha | ||
|---|---|---|
| ESU Name | Initial/Revised Status | Current Status |
| Even-year ESU | ||
| Odd-year ESU | ||
