Christie et al., 1996:

Introduction

"The major objective of the sessile benthic component of the Long Term Monitoring Program (LTMP) is to monitor the status of coral dominated benthic communities by detecting and quantifying major spatial and temporal changes in the abundance of benthos.

A video technique has been developed at the Australian Institute of Marine Science (AIMS) to achieve this objective. The video technique is a relatively new method used to quantify percentage cover of reef benthic communities (Carleton and Done 1995). This survey technique has replaced the time consuming line intercept method (Marsh et al. 1984, Loya 1978).

The video technique has the advantage of being quicker to implement in the field than the line intercept method and it provides a permanent record of the reef benthos (the video tape). Like the line intercept method, it can be used in most diving conditions, including limited visibility. It is also an easy technique for an experienced diver to learn.

The purpose of this Standard Operational Procedure manual is twofold. Firstly, it is an explicit account of the methods used by this program at AIMS, consequently some aspects of the manual are specific to the equipment used in this program. Secondly, it is intended as a guide for other users who wish to use video technology to monitor reef communities."

Sampling design

"Reef benthos communities are surveyed annually within six sectors of the Great Barrier Reef (Cooktown/Lizard Island, Cairns, Townsville, Whitsunday, Swain and Capricorn Bunker sectors). In each of these sectors (with the exception of the Capricorn Bunker sector) three shelf positions (inner, mid and outer) have been identified. Three reefs are nested within each of these shelf position/sector combinations.

In the Capricorn Bunker sector, only outer shelf reefs are represented, with four reefs being surveyed. Shelf position is determined by the position of the reef relative to the coast and continental slope, with inner shelf reefs closest to the coast.A single habitat is surveyed on each reef, typically situated on the north-east flank of the reef. It is defined as the first stretch of continuous reef with a slope less than vertical, going in a clockwise direction from the back reef zone towards the reef front.

The selection of a common habitat allows comparisons to be made between reefs, both within and between sectors. Within this habitat three sites are selected, each containing five, permanently marked, 50 metre long transects, lying roughly parallel to the reef crest. Further details of the design can be found in Oliver et al. (1995).

Transects are set-up along the reef slope (at a depth between 6 and 9 metres). Each transect is marked at the beginning and at the end with a star-picket and at 10 metre intervals with steel reinforcing rods (10 mm diameter). A tape stretched between the star-pickets and rods marks the centre line of each transect. Each star-picket is labelled with an aluminium tag (identifying the transects as belonging to AIMS project 221). The GPS position of the star-picket at the beginning of the first transect of each site is recorded in a database. This star-picket is also marked with a subsurface buoy to aid in locating the site.

Fish abundance surveys and benthic surveys are conducted along each transect. The benthic surveys are conducted approximately 50 cm from the tape, horizontal to the substrate on the upper slope side. The video camera is kept a consistent distance from the substrate (25 cm). The resulting belt transect to be analysed is approximately 25 cm by 50 m."

---

Citation and/or URL

Christie, C.A., Bass, D.K., Neale, S.L., Osborne, K. & Oxley, W.K. 1996, Surveys of sessile benthic communities using the video technique, Australian Institute of Marine Science, Long-term Monitoring of the Great Barrier Reef Standard Operational Procedure: No. 2, Townsville, Qld, Australia

 http://www.aims.gov.au/pages/research/reef-monitoring/ltm/mon-sop2/sop2-00.html

Spatial Coverage

Not applicable 

Temporal Coverage

Not applicable

Update Frequency

Not applicable 

Other Information

'Manta tow' is another method used by AIMS to estimate broad-scale coral cover.