Wetlands Australia 31: The role of Reef wetlands in a warming world
Authors: Great Barrier Reef Marine Park Authority
The role of wetlands is critical in supporting the healthy functioning of the Reef. There is increasing recognition of the role that wetlands play in supporting biodiversity, storing carbon, regulating greenhouse gas emission sources, being a refuge for wildlife during drought periods, and buffering our coastlines during extreme weather events. Wetlands also support Queensland’s primary industries, as saltmarsh, mangrove and seagrass wetlands provide nurseries for fish and seafood to grow. Some wetlands also provide water for irrigation and farm animals.
Even though there are many different types of wetlands, all are dependent on water cycles. Changing rainfall patterns (distribution, time of the year, quantity), extreme weather events and rising temperatures all affect water cycles and wetland hydrology. This results in modification of wetland structures and functionality. Climate impacts are likely to speed up changes in the water cycle which then has flow-on affects for the Reef.
Increased flooding results in greater freshwater flowing directly into the Reef which can cause coral mortality in exposed reefs. Flooding can also make it more difficult for migratory fish, such as mangrove jack, to move upstream. Stream bank erosion during flooding increases the nutrients and sediments flowing to the Reef.
The Great Barrier Reef Marine Park Authority, as lead managers of the Great Barrier Reef, recognises that healthy coastal ecosystems are critical for the long-term health of the Reef. Our Coastal ecosystems position statement is focused on protecting, maintaining and restoring coastal ecosystems which are critical to supporting Reef recovery.
As part of the Great Barrier Reef Marine Park Authority’s Reef Guardians program, learning about wetlands and their role in supporting a healthy Reef is one of the many activities students undertake.
A recent example is students from seven schools across Mackay, Queensland, who visited a new fish passage and wetland lagoon which was built to restore connectivity between Lagoons Creek and the Pioneer River. They planted trees and learnt about the migratory species that travel between upstream freshwater habitats and the Reef, and how improving waterway connectivity has a positive impact on fish numbers and sustainable fishing on the Reef. Students were reminded of the Reef’s close vicinity to coastal towns and cities, and the resulting impacts this can have on the Reef’s health.
Recognising the links between coastal ecosystems and the Reef is important to managing the long-term health and resilience of the Reef in a warming world.
Mackay school students learning about their local wetlands. Photo: Great Barrier Reef Marine Park Authority