Key environmental pressures
In the 2021–22 monitoring season, pressures affecting inshore Reef seagrass habitats were considered to be low but variable among regions and habitats.
There was limited cyclone activity, with only ex-Tropical cyclone Tiffany crossing the Eastern Cape York coast in early January 2022.
Read the latest Marine Monitoring Program Annual Report 2021-22 Inshore Seagrass Monitoring.
How did inshore seagrass meadows respond?
- Inshore seagrass meadow condition improved slightly in 2021-22 from the previous year, but with the condition remaining ‘moderate’. However, trends were not uniform across the Reef.
- Improvements in condition were detected in the northern and central regions, while southern NRM regions (Fitzroy and Burnett–Mary) declined.
- Substantial decrease in Abundance was observed in the Mackay-Whitsunday and Fitzroy regions, where meadow extent remains low and highly fragmented. This condition is likely a legacy of impacts such as Tropical cyclone Debbie in 2017 and localised disturbances.
- The Resilience indicator continued to improve in 2021–22, suggesting a recovering trajectory for Reef seagrass habitats following the seven-year low up to 2019–20. However, seagrass in very southern regions remains vulnerable to further disturbances.
- During the 2021–22 monitoring year, the seagrass condition Index score for the Cape York region improved slightly since the previous reporting period, with the overall grade remaining ‘moderate’.
- In the 2021–22 monitoring period, the seagrass condition for the overall Wet Tropics region improved to ‘moderate’.
- In the Burdekin, the condition of seagrass meadows across the region was unchanged overall and remained ‘moderate’.
- Seagrass meadows across the Mackay–Whitsunday region improved in the overall condition in 2021–22 to ‘moderate’, mainly driven by improvements in the Resilience indicator.
- Seagrass meadows in the two southernmost inshore regions (Fitzroy and Burnett–Mary) remained ‘poor’ and their condition continued to decline.
What is monitored and where?
Inshore seagrass meadows are monitored in four types of habitats: estuarine, coastal intertidal and subtidal, and reef intertidal.
- Two main indicators are assessed:
- Abundance (per cent cover)
- Resilience (resistance and recovery potential – full details of the resilience metric can be found in the Resilience in practice report)
In addition to these indicators, seagrass species, the size and patchiness of the seagrass meadows, and the density of seeds in the seed bank are also assessed.
Factors that can affect seagrass conditions are recorded, which include within-canopy seawater temperature, the amount of light reaching the plants, the sediment characteristics, and the abundance of macroalgae and epiphytes.
- Six regions are included in the sampling design:
- Cape York
- Wet Tropics, Burdekin