Helicopters, far north Queensland tropical sunshine and seagrass surveys. It was all part and parcel of a research trip by a team of scientists from James Cook University's Tropical Water and Aquatic Ecosystem Research (TropWATER) to monitor seagrass in North Queensland Bulk Ports' Port of Weipa.
For 20 continuous years (since 2000) NQBP has commissioned the JCU team to monitor seagrass conditions in the Weipa port area. JCU's Associate Professor and TropWATER co-director Michael Rasheed said seagrasses are a critical component of the marine environment.
"The seagrass monitoring program covers 30,000 hectares across NQBP’s four trading ports which also include Hay Point, Mackay and Abbot Point in the Great Barrier Reef World Heritage Area," Dr Rasheed said.
"Seagrasses are a critical component of the marine environment in the Port of Weipa as they are a nursery ground for prawns and fish and are food for turtles and dugongs. Additionally, seagrasses trap and stabilise sediment protecting the coastline and are a sink for carbon helping to mitigate climate change."
Dr Rasheed said the JCU TropWATER team conducted surveys from both boats and helicopter flights covering more than 5000 hectares of seagrasses.
"There's six species within the port limits. The team assesses seagrasses each September/October at the peak of seasonal seagrass growth," Dr Rasheed said.
"We take a range of measurements including the area of seagrass meadows; the species present biomass (seagrass density); the amount of light that reaches seagrasses to support their growth and tracking and analysing any changes over time."
The JCU TropWATER team conduct surveys over a week during low tides, when the majority of seagrasses are exposed out of the water and therefore easily mapped and assessed rapidly using helicopter survey methods.
"Deeper areas that don’t expose are surveyed using remote camera systems," Dr Rasheed said.
The Weipa region experienced an extreme wet season in 2018/2019, with three tropical cyclones between December 2018 and March 2019. This lead to an extended period of low light in the seagrass meadows.
Seagrasses were able to maintain a good condition despite these impacts due to their resilience and the latest surveys indicated positive signs.
"In the latest survey in September 2020 seagrasses appeared to be in a healthy condition, with the team busily analysing the results for the annual report which will be available early next year," Dr Rasheed said. See seagrass data come to life on NQBP's seagrass dashboard.
