Skagit Chinook escapement assessment using Unmanned Aerial Vehicle (UAV)

This project is a stock assessment and research project to improve Management of a valuable tribal resource. The project is designed to monitor and enumerate spawning abundance using unmanned aerial vehicle (UAV) system technology as a compliment to helicopter surveys operated by Washington Department of Fish and Wildlife. These methods are implementing aerial spawning surveys to estimate salmon escapements. The present method deploys helicopter flights. The additional UAV missions would help assure full survey coverage during Skagit Chinook spawning period. Ground surveys will also be conducted to ground truth and collect biological data for stock assessment needs.



The proposal would cover the implementation of a 5th year of this continuing project. The UAV missions will be deployed to assess the six Chinook populations on the Skagit River system. The survey river reaches would include the Skagit River, Cascade River, Suiattle River, and Sauk River. Surveys will be implemented once every 10 to 14 days per population as water clarity conditions dictate. Spawning occurs from late July through early November depending on the Chinook population. The UAV missions planned for the Sauk summer Chinook population will explore beyond-line-of-site deployment. Additional UAV missions will be deployed on the White Chuck River in the form of spot checks to identify chinook spawning activity and distribution.

It is essential for managers to collect accurate escapement data for Sauk summer Chinook considering the increased environmental impacts to such a vulnerable population. Days for optimal aerial surveys under good water visibility conditions is decreasing during the spawning period. The logistics of booking a helicopter reduces survey opportunities too especially considering flight and river visibility conditions can change within hours. An Unmanned Aerial Vehicle (UAV) can be deployed immediately when good aerial survey conditions are present