Those pesky little buggers are everywhere up here on the American River… best to be prepared and bring some bug spray to make sure you are not eaten up! The mosquitoes are usually out in the evening in the middle part of the summer. As the night goes on and temperatures cool the mosquitoes tend to disappear.
I hope that this helps, as always if you have questions about this information, or have other questions about river trips, please feel free to E-Mail me, I am always here to help no matter what or where your river adventure is taking you.
Hope to see you on the river this year,
Flash (over 30 years of river rafting experience around the world and back)