Darwin Harbour
Integrated Report Card

Mangrove Area Change

Mangrove extent along the creeks, rivers and coastline of Darwin Harbour is assessed annually using satellite imagery to detect the expansion or contraction of mangrove forests. Mangrove forests naturally grow and shrink in response to natural and human induced pressures. Data is analysed by the Northern Territory Government.


Photo of a mangroves at sunset in Darwin Harbour taken by Geoff Whalan, used under CC BY-NC-ND 2.0.

Scoring method

For the purposes of this report card, no change (or an increase) in mangrove area compared to a 2016 baseline, equates to a very good report card grade (A); and a net loss of 3% or more of mangrove area compared to a 2016 baseline, equates to a very poor report card grade (E).

In order to standardise the reporting scale across all indicators, the net percent mangrove area change for each reporting region in 2020 was converted to a 0-100 report card scale using the relationship shown in this graph.


Mangrove area change within Darwin Harbour appeared to show a slight decrease in mangrove extent across the harbour (<1%) between 2020 and 2016, resulting in a moderate rating (C+) for the harbour as a whole. The data used to assess this indicator were, however, still in draft format at the time of publishing this report card. As such, this finding is of low confidence and work is underway to improve the confidence and sensitivity of this indicator moving forward.