Coulon Beach and the mouth of the Cedar River are fun places to view many bird species. But one must also widen the choice to include one of the major King County trails in the area:
The Cedar River Trail extends 17.3 miles from the City of Renton through Maple Valley and to the border of the Cedar River watershed. It passes through excellent bird and wildlife habitat. Eagles, hawks, herons, mallards, deer, elk, coyotes - you name it! It's a pleasant walk or bicycle ride. My hope is that someday soon the efforts to connect the Soos Creek Trail (of which I live near) to the Cedar River Trail will reach fruition, giving the recreationist even more options.
The Cedar River enters Lake Washington near Coulon Beach, which offers even more opportunities for birding. Herons can be spotted in large numbers here (55 on Jan 31, 2009), as can Mallards and various types of ducks and geese. The best viewing point is near the bridge accessing the Nature Island bird sanctuary. The island has benches for sitting and relaxing while absorbing the views, as well as two separate observation points.
Please respect the wildlife and the enjoyment of others by staying on the established viewing path.