Inshore seagrass and habitat condition: ²⁰

• In the 2019–20 monitoring period, the seagrass condition index remained relatively stable and was graded as poor.
• The abundance score increased marginally on average, but remained poor.
• Reproductive effort has remained low since 2011–2012 and scored very poor in 2019–20 for the seventh year in a row. Therefore, fluctuations in the seagrass condition index over the last seven monitoring periods have been primarily driven by fluctuations in abundance and tissue nutrient status.
• Tissue nutrient elemental C:N increased slightly in 2019–20, but remained on the grade threshold of poor.

Seagrass abundance, composition and extent: ²⁰

• In 2019–20, coastal and reef sites declined in abundance relative to the previous period, however, this was offset by the estuary sites where one site (GH1) doubled in abundance and the other site remained stable. Seagrass abundances (per cent cover) in the Fitzroy region in 2019–20 were significantly higher in coastal (18.2 ±0.7 per cent) and estuarine (11.2 ±1.8 per cent) habitats, than reef (0.5 ±0.3 per cent). Seagrass abundances across all habitats were higher in the late dry than the late wet season (e.g. coastal 25.2 ±0.7 per cent and 11.2 ±0.7 per cent, respectively).

• Seagrass abundance at estuary and coastal intertidal habitats has fluctuated greatly between years over the life of the monitoring, with some sites experiencing total or near total loss followed by recovery. In 2019–20, all but one of the coastal sites decreased in abundance relative to the previous period, but the increase at GH2 was enough to slightly elevate the score for the region.

• Examination of the long-term trend in seagrass abundance (per cent cover) across the region reveals a significant decrease. These decreases have primarily occurred in the estuary and reef habitats, although two thirds of all monitoring sites in the region (including coastal) show no significant trend.

• Seagrass abundance in the estuarine habitat — believed to be low due to a legacy of a mud wave traversing across the meadow — is showing signs of recovery at GH2, leading to a general increase in abundance for the habitat type. As the mud wave dissipated in 2018–19, meadow integrity (e.g. reduced scarring) improved.

• In the north of the region, coastal sites receive low river discharge, however, the meadows were still exposed to turbid ‘brown’ sediment laden waters for much of the year. There turbid waters could be partly the result of wind-driven resuspension, but appear mainly the consequence of the extreme tidal movement in Shoalwater Bay (some of the highest along the Queensland coast).

Seagrass reproductive status: ²⁰

• Reproductive effort has varied inconsistently among habitats in the Fitzroy region over the life of the MMP. Reproductive effort is higher in the late dry season and remained steady at coastal and estuary sites in 2019–20. A seed bank has also persisted at coastal and estuary sites since 2012.
• Reproductive effort has remained very low at reef sites and were absent in 2019–20 together with the seed bank. This limits the meadow capacity to recover following further disturbance.

Epiphytes and macroalgae: ²⁰

• Epiphyte cover on the leaves of seagrass in estuarine habitats of the Fitzroy region increased in 2019–20 to above the overall inshore Reef long-term average for the first time in four years. At coastal habitats, however, epiphyte abundances continued to fluctuate and at reef habitats remain below the overall inshore Reef long-term average for the seventh consecutive year.

• Macroalgae cover remained very low and below the overall inshore Reef long-term average at all habitats in the Fitzroy region, with a minor deccrease at the reef habitat.