Al:
From the imagery, it looks like there are still plenty of mangroves on the southern shore of Shoal Reach, out the front of Bullo River. Just upstream around the bend, also on the southern shore, Bull Creek, Boundary Creek, and Packsaddle Creek appear mangrove-fringed at their mouths. ....and that about pulls it up. That would be around 129 degrees 57.5 minutes East.

Might have to plan a field trip to collect some 'ground truth' data!