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June 2022
This update is about the native trees and shrubs that grow along rivers and streams in our region: the riparian habitat of the Rogue watershed.
In ODFW’s new Rogue-South Coast Multispecies Conservation and Management Plan, riparian protection and restoration are key actions to address:
- Water temperature - a primary factor limiting salmon and steelhead abundance.
- Illegally introduced fish species - a secondary limiting factor related to water temperature.
- Building resilience to climate projections.
A healthy, multistory canopy of native trees and shrubs grows more fish because it grows survivors—young salmon and steelhead that survive in the Rogue Valley for one to three years to reach the smolt stage, and then head to sea.
We hope you join us in spreading the word about the importance of riparian vegetation and allowing that vegetation to mature. Even dead trees are important for Oregon’s fish and wildlife.
What is a riparian area anyway? It is the land next to a wetland, pond, lake, stream, or river. The waterway affects the type of vegetation that grows, and the vegetation affects the waterway. Riparian areas provide a rich habitat of native trees and shrubs and support a variety of fish and wildlife species.
Why are riparian areas so important? Healthy riparian areas are key to productive fish populations and to wildlife that live in or use these areas. The native trees and shrubs growing in riparian areas shade the water, keeping it cool for fish and creating hiding places so they can escape predators. This vegetation also reduces erosion and filters runoff including soil and pollutants. Native vegetation produces additional food for fish, and nectar, seeds, fruits, and acorns that feed a wide variety of wildlife.
If amphibian, reptile, bird and
mammal communities were combined,
riparian areas would support more
species than any other habitat type.
Counts by the Rogue Valley
Audubon Society found over
130 bird species using riparian habitat
along the Bear Creek Greenway.
Dead trees are important too! Just as salmon and steelhead have a life cycle, trees do as well. When trees die, the standing snag provides important habitat for wildlife. Many birds nest in or on large snags. Nests built by birds like hawks are very visible. Less visible are woodpecker cavities created for nesting. Many other birds also nest in the cavities built by woodpeckers.
When a tree dies and falls over, is cut down by beavers, or blows over, it can land in or next to the stream. These dead and downed trees, often referred to as Large Woody Debris (LWD) also benefit the stream ecosystem. LWD slows the flow of water and scours rearing pools. Slow water eventually lets gravel collect to provide spawning areas for fish. LWD allows streams to flow in portions of the floodplain during higher flows, increasing the amount of fish habitat in winter. The floodplain acts like a sponge, slowly releasing cool ground water back to the creek throughout the summer.
LWD on the ground within the riparian area helps slow flood waters that occur periodically. Slowing flood waters helps protect the banks from large scale erosion events and allows sediment in the flood waters to drop out of the water and build soil. As LWD decays on the streambank, it eventually becomes part of the riparian area soil, which will grow another tree to start the cycle all over again.
Rules that protect riparian habitat. Oregon Land Use law directs cities and counties to adopt regulations that protect riparian areas.
Regulated riparian setbacks are generally part of city or county ordinances and are administered by a planning department or planning commission. The ordinance spells out what development activities are legally allowed next to streams.
In the Rogue watershed, there are a variety of legally regulated riparian setbacks, however some cities have little to no legal protections in place. For information on the rules in your community, ODFW recommends checking in with your local planning department. A list of ordinances in the Rogue watershed is also available on the ODFW website below: https://www.dfw.state.or.us/fish/local_fisheries/rogue_river/docs/Rogue_Riparian_Setbacks.pdf
Exceptions let landowners remove non-native vegetation, such as blackberries, in many of the regulated riparian areas. Developing and implementing a Riparian Landscape Plan is a requirement prior to vegetation removal, and ODFW often helps landowners develop their plan to meet city or county requirements. The landowner can then apply for a land use permit with their city or county to lawfully complete the work.
You can help protect riparian areas. Do you care about the salmon and steelhead of the Rogue? Then please get involved in riparian restoration and protection in the city or county where you live. Call your local planning department and find out how to track development proposals and code enforcement. ODFW can provide advice as well.
If your ordinance is not effective, work with your elected officials to strengthen it. And let your local government officials know that you care about riparian habitat, and you want the ordinance to be implemented. Let native vegetation grow! The fish will thank you.
 Maturing riparian vegetation at confluence of Walker and Emigrant Creeks (Bear Creek). Ask city and county governments to protect riparian habitat—and let native vegetation grow!
The Rogue, climate projections and non-native fish. The Rogue Watershed is no stranger to drought and hot summers. Most of our precipitation comes in winter followed by hot and dry summer months. Just as you may be donning a hat or sunscreen in the summer to keep from getting a sunburn, riparian areas help lessen sun exposure to water bodies which can increase water temperatures. Walking into the cool shade next to a creek is a welcome thing on a blistering 90-degree day. Remember, if you need shade, native fish need shade too!
The Rogue watershed is also no stranger to the illegal introduction of non-native fish. Two non-natives are in the minnow family: pikeminnow and shiners. Redside shiners have been in the watershed since the 1950s and pikeminnow since the late 1970s; both have spread throughout the basin.
The minnows thrive in water that is warmer than cool water preferred by salmon and steelhead. As water temperatures rise, redside shiners outcompete young steelhead for the best available holding and feeding habitat in a stream. When stream temperatures are cool, steelhead outcompete the invasive shiners.
In a stream with a heavy population of illegally introduced minnows, shiners can often outnumber young of the year steelhead 10 to one or even more. Sand Creek, a local stream in Grants Pass is a perfect example.
In the past, wild steelhead were produced higher in the watershed because riparian vegetation cooled the water. Without that cooling canopy, shiners outcompete the steelhead.
Recently, volunteers working with the Salmon Trout Enhancement Program (STEP) operated a juvenile fish trap in the lower reach of Sand Creek where water temperatures can exceed 76 degrees. Shiners dominated the catch (see photo below).
 Redside shiners come in many size classes and large schools. The ruby red fathead minnow in the photo is another non-native fish.
Most climate scenarios predict hotter conditions and more frequent and severe droughts - scenarios that favor the production of non-native fish like the redside shiner at the expense of native fish like steelhead. Nonnative species will make a warmer future even worse for Rogue salmon and steelhead. This is why ODFW’s new conservation plan emphasizes the need to grow a healthy, multi-story canopy of native riparian vegetation, and protect that vegetation as it matures. Fully functional riparian habitat is needed for the bigger climate changes expected 30-50 years in the future.
 Wild steelhead, brought to you by healthy riparian vegetation.
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