Marine Ecology

Mangrove health 

Mangroves play a vital role in reducing the amount of waste entering the ocean by capturing nutrients, sediments and pollutants. Port of Brisbane is located adjacent to some of the largest mangrove ecosystems in Moreton Bay.

Since 1999, PBPL has monitored the ecological health, species composition and structure of the mangroves adjacent to the port. Monitoring takes place annually and includes field surveys, GIS mapping and photographic monitoring to identify changes over time.

Data collected from the monitoring since this time indicates that the health of the mangrove community has declined during the monitoring period, with fluctuations in health caused by severe weather events (drought and floods) and changes in the quality of water in Moreton Bay. 

Latest monitoring and research (at a glance)

Monitoring

  • The most recent mangrove health monitoring was conducted in 2017.
  • As part of this, PBPL reviewed historical data and revised the monitoring methodology to include new technology to gain a better understanding into the current health of the ecosystem.
  • The 2017 monitoring mapped changes between 2016 and 2017 using remotely sensed data and ground surveys. 
  • The new technology included a UAV to capture high resolution mapping of the mangrove community and satellite imagery to determine long-term changes in mangrove condition from 1999 to 2016.
  • Brisbane is the first Australian port to use a UAV to undertake mangrove health monitoring.
  • Using a UAV ensured the entire mangrove community could be monitored and also removed health and safety risks associated with field surveys.
  • The review of historical data showed a strong correlation between rainfall and mangrove health, explaining changes in mangrove health over time.

Research

  • In 2016, PBPL embarked on a research program in partnership with the Moreton Bay Seafood Industry Association to develop an assessment tool to predict the value of mangroves and other marine habitats for commercial fisheries.
  • The research highlighted that the interconnectedness of different marine habitats is crucial to maintaining high numbers of commercially valuable fisheries species.
2017 Mangrove Health Assessment Report

Recent projects 

In 2016, PBPL worked with Moreton Bay Seafood Industry Association in order to develop a tool to assess the value of coastal seascapes that are adjacent to the Port of Brisbane.

The study showed that seagrass communities are more important than mangrove communities for predicting the value of commercial fisheries adjacent to the Port of Brisbane.
 
2017 Coastal Seascapes for Commercial Fisheries Production

Seagrass health

Seagrass is an important flowering marine plant that forms meadows in shallow, sheltered waters.

Seagrass meadows provide important habitat and food for many marine animals including dugongs, turtles, sea urchins, fish, shore and water birds and benthic fauna. There is a large seagrass meadow adjacent to the Port of Brisbane, which has a considerably high biodiversity value.

Since 1991, Port of Brisbane has conducted regular monitoring of this seagrass meadow. The health of seagrass meadows is determined using aerial photography, survey transects and underwater video surveys to assess the seagrass depth range and undertake community profiling and meadow mapping.

Monitoring results show the construction of the Port’s reclamation area has benefitted the growth and health of the seagrass communities by protecting the seagrass in Waterloo Bay from prevailing winds and separation from the mouth of the Brisbane River.

So much so that since 1991, the seagrass meadows adjacent to the Port have increased by 200% and now cover 1,400 hectares. 

Latest monitoring (at a glance)

  • The most recent seagrass monitoring occurred in 2017.
  • Results show that the meadows located adjacent to the port are slowly expanding and recovering from damage that occurred as a result of the 2011 and 2013 floods.
  • The results also show that port activities have not resulted in seagrass loss at Fisherman Islands.
  • In fact, the overall long-term trend to date has shown a net expansion in seagrass meadows at Fisherman Islands due to the shelter provided by the Port’s reclamation area.
2017 Seagrass Monitoring Report

 

Future Port Expansion seawall

Port of Brisbane’s Future Port Expansion (FPE) seawall, located in the Port’s reclamation area was completed in 2005 and extends over 4.6km.

Over time, the FPE seawall has become an important habitat for a diverse range of benthic flora and fauna communities, supporting a vast array of marine life including macro-algae, corals, sponges, anemones, crayfish and fish. 

Monitoring is undertaken every five years to investigate the quality and extent of this important habitat within the wall.  Data is gathered through field surveys using transects and underwater cameras to assess changes over time.

Latest research (at a glance)

  • The most recent monitoring was undertaken in 2014

  • Results show the FPE seawall continues to support benthic flora and fauna communities, consistent with the 2009 survey.

  • The FPE seawall was also identified as an important habitat for local fisheries. The crevices in the wall and high macro-algae cover provides shelter for small reef dwelling species (crayfish, sea urchins, soft and hard corals etc.) and large schools of fish that are of direct significance to commercial fisheries.

2014 Future Port Expansion Seawall Ecological Assessment