Parks Victoria Standard Operating Procedure

More documents

Recommendations

Info

Parks Victoria Technical Series No. 9Subtidal Reef Monitoring SOPThis document details the field procedures used to obtain the data, the post-field proceduresused to manage the data, and the scientific observer training required as part of the VictorianSubtidal Reef Monitoring Program. The operating procedures described here are designed tominimise biases and error associated with underwater visual census techniques, as well ascomply with quality and occupational health and safety policies.This subtidal reef monitoring procedure integrates with standardised procedures formonitoring intertidal and deep reef, deep sediment, seagrass and shallow sediment habitatsin Victoria and elsewhere in southern Australia.3
Parks Victoria Technical Series No. 9Subtidal Reef Monitoring SOP2.0 Overview of the Methods2.1 GENERAL DESCRIPTIONThe Edgar-Barret methods (Edgar and Barrett 1997, 1999; Edgar et al. 1997) are generallyused for the repeated census of a set of sites within locations (usually within 10 km ofcoastline). The position of each site is fixed, as with the position of transects surveyed withineach site. Two hundred metre transects of four contiguous 50 m sections are surveyed ateach site.Where possible, sampling is along the 5 m (± 1 m) depth contour, to minimise spatialvariability between sites. The depth of 5 m is considered optimal for monitoring becausediving times are not limited by decompression schedules and these reefs are subjected toheavy fishing pressure from wrasse fishers, rock lobster fishers and divers. Sampling inVictoria at some sites has to be deeper or shallower, depending on the available habitat andexposure to wave action, with sites ranging between 3 and 7 m deep.Each site is located using differential GPS and marked with a buoy, or the boat anchor. A100 m long numbered and weighted transect line is run along the appropriate depth contoureither side of the central marker. The resulting 200 m of line is divided into four contiguous50 m sections (T1 to T4). The sections are orientated the same way for each survey, with T1generally toward the north or east (i.e. anticlockwise along the open coast).For each transect, four different census methods were used to obtain adequate descriptiveinformation on reef communities at different spatial scales. These involved the census of: (1)the abundance and size structure of large fishes; (2) the abundance of cryptic fishes andbenthic invertebrates; (3) the percent cover of macroalgae; and (4) the density of string-kelpMacrocystis plants. A fifth method was recently implemented to document the abundance ofinvertebrate grazers within sea urchin barrens present in eastern Victoria. This method isonly used at a small number of sites. The depth, horizontal visibility, sea state and cloudcover are recorded for each site. Horizontal visibility is gauged by the distance along thetransect line to detect a 100 mm long fish. All field observations are recorded on underwaterpaper. The following descriptions for Methods 1 to 3 are derived from Edgar and Barrett(1997).2.2 METHOD 1 – MOBILE FISHES AND CEPHALOPODSThe densities of mobile large fishes and cephalopods are estimated by a diver swimming upone side of a 50 m section, and then back along the other. The diver records the number andestimated size-class of fish, within 5 m of each side of the line. The size-classes for fish are4
Page 1 and 2: P A R K S V I C T O R I A T E C H N
Page 3 and 4: Parks Victoria Technical Series No.
Page 9: Parks Victoria Technical Series No.
Page 56: Parks Victoria is responsible for m

Parks Victoria Standard Operating Procedure

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?