The Benefits of Mangroves (2023)

Brisbane's lord Mayor Clem Jones is famous for two things: installing the sewers (before then the city was septic tanks in the main) and digging up the mangroves, which he disliked on aesthetic reasons. Silting became a huge issue in the river and water quality declined overall for complex reasons, but the lack of mangroves definitely affected fish stocks.

Post Clem Jones, the mangroves have mostly recovered, although flooding causes some die-back. Fish stocks are huge, recreational fishing is all up the river, the prawn industry is back in the lower reaches, the river is not crystal clear but its significantly better overall. Bull sharks live in the upper reaches of the city, we see dolphins from time to time, threadfin salmon, eel, and bait fish. Herons, Kingfishers, Pelicans, sea eagles and kites up and down the river.

The city has high(ish) speed commuter catamarans, ploughing up the water from the docks up stream to the university and mangroves help stabilise the banks which suffer badly from the wash (it's not enough, the council deploys gabions and rocks to try and help halt erosion too)

Mangroves are the fish nursery. They're where young fish hide from predators, where eggs hatch, where prawns and mudskippers live. They provide perches for birdlife, and screen the river from the city. Fruitbats live in amongst them too in some of the quieter stretches.