1. Salmon Spawning Habitat and Sediments
Brad Dunker
Municipal Creeks Coordinator
Municipality of Anchorage
Parks & Recreation

2. Overview Salmon ecology and behavior during in-migration and spawning
What are some impacts of fine sediments on salmon habitat
Why sediment control and road crossings are important to salmon
Here are some basic questions that I hope we can have an understanding about by the end of the 15 minutes.

3. Physical Parameters and Embryonic Development
“Simple” relationship between physical parameters and steelhead embryonic development. We won’t go over this slide in detail, but just to show you that salmon ecology isn’t always as easy to understand as we would like it to be.

4. Salmon Ecology Important factors include: Temperature
Habitat availability
Water velocity
In-redd flows

5. Temperature
Embryos typically emerge from the redd

6. Temperature
13-16° C= ideal temperature for fish to gain weight (in lab)
22-25° C fish stop feeding/spawning
+25° C mortality occurs
Especially critical for juvenile salmon
Salmon embryos have a limited ability to escape from detrimental environmental parameters.

7. Habitat and Velocity
Substrate is important for embryonic and juvenile salmon survival
Provides:
UV Protection
Crushing/Vibration impacts
Cover from predation
Water Velocity is related to substrate and causes impacts on redds

8. Redd Making

9. Redd Attributes

10. Habitat and Sediment
Fine sediments (% of fines) is critical to habitat quality
Reduces:
Oxygen Supply
Metabolic waste removal
Ability to stabilize temperature
Success of aelvan emergence

11. In-gravel Flow

12. Sediment and Embryo Survival

13. “Good” Sediments? Natural Gravel transport Human Gravel transport
Gravels native to that stream system that naturally flows downstream
Human Gravel transport
Gravels not native to that stream system that are placed by construction activities or restoration projects

14. Gravel Augmentation Project

15. Gravel information Handling:
Typically handled around 10 times before it is placed in a culvert/streambed
Sits in yards after it is processed gaining sediments
Must meet native gravel size criteria to be effective

16. Construction Tips Equipment Storage sites away from stream bank
RUBBER TIRES!
Environmentally-friendly fluids in equipment
Storage sites away from stream bank
Gravel quality and specs

17. Thanks!