We are thinking of communities in the Far Northern region affected by Tropical Cyclone Narelle.

Tropical Cyclone Narelle passed through the Far Northern region of the Marine Park as a Category 5 system and crossed the Queensland coast as a Category 4 on 20 March. The cyclone generated intense winds and strong wave action along its track in the Far Northern Region, with modelling also indicating wide-spread high wave action in the Northern region, particularly across offshore reefs. The extent of damage will be assessed in the coming weeks.

The El Niño–Southern Oscillation (ENSO) climate pattern, La Niña, continues to weaken, and conditions are expected to return to a neutral phase in early autumn. However, forecasts suggest that by winter, the system may shift into an El Niño phase, which often brings warmer and drier conditions to much of Australia.

Temperature

Sea surface temperatures continue to fall across the Marine Park, with the largest drop (0.8°C) recorded in the Northern region, however they remain around 0.6°C above the long-term monthly averages.

Despite recent decreases in sea surface temperatures, some reefs in the Far Northern and Northern regions have accumulated heat stress exposure that can cause some coral species to bleach.

Rainfall

From 16–22 March, localised heavy rainfall was recorded in the Cape York and Wet Tropics catchments as Tropical Cyclone Narelle moved through the region. Weekly rainfall totals ranged from 200–450mm, with some locations receiving more than 100–200mm in a single day.

Flood warnings are active across parts of the Cape York catchment, and significant flooding has been reported in the Pascoe River, which is currently at record levels.

Reef health

Over the past week, 67 Reef Health Impact Surveys were completed across nine reefs in the Northern (between Innisfail and just above Cooktown), Central (between Mackay and Innisfail) and Southern regions (between Bundaberg and Mackay).

Coral bleaching in the Northern region varied from moderate (11–30%) to very high (61–90%). Of the five reefs surveyed, one reef also showed signs of coral mortality. These impacts are likely linked to a combination of exposure to ongoing heat stress and recent floodwaters.

In the Central region one reef was surveyed, with no bleaching recorded.

In the Southern region 3 reefs recorded medium (11–30%) coral bleaching prevalence.

Additional Eye on the Reef observations from across the Marine Park reported bleaching on 9 of 20 surveyed reefs. Coral damage was recorded on 6 reefs, and coral disease was observed on 3 reefs.

Crown-of-thorns Starfish Control

The Crown-of-thorns Starfish Control Program continues to manage ongoing outbreaks across the Marine Park, with updates shared in the first weekly Reef Health Update of each month.