Walking along the River is amazing, there is a sanctuary off King William Street, it hasn't been commercialised yet so it is in fairly rustic condition
If you walk on the other side of Garret Rd, you can also see birds in the rushes and bush by the path. Sometimes gives a different perspective - watch out for snakes in the area.
The best birds can be found at the bird sanctuary along the river.
Yes - The Eric Singleton Bird Sanctuary is at the end of King William St Baywater - near the Riverside Gardens Area. There is a lake and a bird hide to look over the water.