2013 coral reef survey in Torres Strait (NERP-TE 2.3, AIMS)

As part of Project 2.3 broadscale surveys and biodiversity assessments were conducted in the central island group and eastern island group within the Torres Strait region.

Manta tow (broadscale surveys)

Broadscale surveys were conducted by manta tow in February 2013 at Aureed Island Reef, Aukane Island Reef, Kabbikane Island Reef, Masig Island Reef, Mer Island Reef and Waier and Dauar Island Reef.

Biodiversity surveys

Lists of scleractinian coral species and fish species were collected in February 2013 at Poruma Island Reef, Aureed Island Reef, Masig Island Reef, Erub Island Reef and Mer Island Reef, shown in the image below. Species level photos were collected.

Fish and hard coral biodiversity surveys

The results of biodiveristy surveys are published in (Ref) For methods used and a list of fish species observed within the Torres Strait region by CSIRO in 2007 and additional records from the survey in 2013, please refer to the appendicies in the report.

Surveys of reef benthos

Photo transects

Photo transects were taken in representative habitats on each island to provide context for the biodiversity assessments and to establish baseline data on benthic community composition. Habitats sampled included the reef flat, reef crest, reef slope and lower reef slope. The depth range of the reef slope varied from the central to eastern islands. The lower slope transects was near the base of the reef slope. The slope transects were typically around 4-6 meters depth but were not located randomly, as areas of higher coral cover were being targetted for the biodiversity surveys. In patchy habitats the estimates of cover would be expected to be higher than if transects were randomly located. The standard methods established by the AIMS long term monitoring project (LTMP) were modified for the surveys in Torres Strait and are outlined below.

At each site, 3 x 10m transects were laid out and sampled by taking a photograph of the substrate at 50cm intervals from a distance of 50cm from the substrate, giving a total of 20 photos per transect. The benthos were analysed using image analysis software developed for the LTMP at AIMS. On each photograph, benthos were identified under 5 points arranged in a quincunx, resulting in 100 samples of benthos per transect and this data was converted to percent cover (%).

Reef Health Impact Surveys

As well as the photo transects mentioned above, Reef Health Impact Surveys (RHIS) sites were established and surveyed in the zone of the reef crest or the shallower part of the reef slope(2-3m). RHIS are part of the Great Barrier Reef Marine Park Authority's (GBRMPA) Eye on the Reef Program, and are intended to be a quick and efficient way to provide a snapshot of reef health at any time, on any reef. In Torres Strait the sites established in 2013 will be monitored by Torres Strait Regional Authority (TSRA) rangers who were trained by GBRMPA staff during the trip.

This page links to a summary page for each reef surveyed in 2013. Summaries of broadscale surveys for each reef included an aerial image of the reef, graphs showing the median percent coral per tow and the number of Acanthaster planci or crown-of-thorns-starfish (COTS) per tow, as well as a text summary. Summaries of benthos for each reef included: site locations, photos of the benthos, graphs showing estimates of main groups of benthos, hard coral families (crest, slope and lower slope) and types of algae (reef flat) and text summarising major trends. Summaries for RHIS sites included graphs for percent cover of hard coral and soft coral.