UPDATE: Habitat Mapping the Great Barrier Reef: Starting with 200 reefs around Cairns and Cooktown

 

Reefs visited and data collected during the April-May field trip.

 

The mapping of the coral reef habitats of the Great Barrier Reef, is going full steam ahead with the recent completion of extensive repeat surveys and mapping for 200 reefs in the area around Cairns and Cooktown.

The mapping combine’s satellite remote sensing imagery, using Landsat 8,  with ecological modelling and mapping rules to create maps showing:

  • Geomorphic zones, areas with consistent bathymetric form, forcing process, and position on reef (e.g. reef slope, reef crest, lagoon).
  • Benthic composition, areas with similar benthic and substrate features (e.g. coral, algae, rock, sand); and
  • Coral types (e.g. plate, branching, massive corals).  

Development of the mapping and modelling work is a collaboration lead by RSRC SEES with Marine Spatial Ecology lab, and Engineering at UQ, AIMS, JCU, GBRMPA and EOMAP.

Peran Bray (RSRC) conducting a georeferenced photo transect survey, while towing a GPS that floats at the surface.

The field data collection is now finalised from  January and May field trips, and data will be used for mapping and modelling calibration (January) and validation (January, and May) activities.  The May field data included  12,000 geo-located photos from 59 transects with a total lenght of 40 km, 57 coral colour surveys  using  www.coralwatch.org, 59 Crown of Thorn surveys and 51 Reef Health and Impact Surveys. 

 

The May trip took place due to the unique collaboration with the Swiss run Ocean Mapping Expedition from 25th April – 20th May, where two RSRC-UQ team members were on board the sailing vessel MV Fleur De Passion.

 

The Swiss mv Fleur de Passion, originally a German mine sweeper rebuild to a sailing vessel, sails around the world as part of the Ocean Mapping Expedition to map underwater sound and plastics.

 

Field trips on coral reefs are a unique way to experience the reef, but can be confronting as well, as the field team found out during the May trip. Sadly, many reefs showed signs of past and current bleaching impacts.  Luckily we also have seen healthy areas but not as many as during the January field trip. Three reefs visited in January were revisited in May to assess the of the March coral bleaching event using Sentinel 2 satellite imagery in collaboration with European Space Agency.

Left to right: Yves Plébert (Crew), Pietro Godenzi (Skipper), Crew, Peran Bray (UQ RSRC), Kathryn Markey (UQ RSRC), Chris Roelfsema, Candy Aeschlimann (Crew), Eva Kovacs and Brea Vincent (UQ RSRC).

The field trips helped to create the first draft map of the geomorphic zonation of the 200 reefs, which is currently being refined.

For more information on the GBR habitat mapping contact Dr. Chris Roelfsema (project PI).

 

Once arriving at the reef, the Fleur de Passion would drop anchor and with the small tender field data would be collected over the reef top. This idyllic picture was taken on possible the only day with lest then 15-20 knot winds in 20 days.

Draft of the geomorphic zonation mapped of 200 reefs, using remote sensing imagery, object based image analysis, field knowledge and geo-ecological based rule sets.