Brief description
The data is quantitative abundance of fish and megafaunal invertebrates and algal % cover derived from transect based counts at a wide range of locations across Temperate Australia. The methods are described in detail in Edgar and Barrett (1997). Primarily the data are derived from transects at 5 m depth and/or 10 m depth at each site surveyed. Methods were initially developed for research on temporal changes following protection in Tasmanian long-term MPAs (Maria Is, Tinderbox, Ninepin Point, Governor Island), and the data represented by this record has been collected at Tinderbox.In many cases the dataset involves temporal replication (year scale), particularly for the core Tasmanian MPAs represented by this record.
Lineage
Maintenance and Update Frequency: asNeeded
Statement: The underwater visual census (UVC) methodology used to survey rocky reef communities involved quantitative diver-based surveys of fishes, large mobile invertebrates and macroalgae (see below for more detail; also described by Edgar & Barrett, 1997 and Edgar et al., 1997).
At each site, 4 x 50m transects were laid at the 5m or 10m depth contour, and fishes, invertebrates (> 2.5 cm) and algae were recorded separately (as described below) by a team of 2 - 3 divers. Details of each site, including the date and GPS location, were recorded.
FISHES:-The density and estimated size-class of fish species within 5 m either side of the 50 m transect line were recorded by a diver (i.e. 50 m x 10 m). This was done by swimming parallel to the transect line (2.5 m away) and recording fish within a 5 m wide lane, on each side of the transect. Size-classes of total fish length were categorised as 25, 50, 75, 100, 125, 150, 200, 250, 300, 350, 375, 400, 500, 625, 750, 875 and 1000+ mm. Lengths of fish >1000 mm length were individually estimated.
MACROINVERTEBRATES:-A diver searched the seabed for a 1 m wide lane along the transect line for cryptic fishes and macroinvertebrates (i.e. 50 m x 1 m). Four 1 m x 50 m transects were surveyed at each site. Algae were swept away from the transect to obtain a clear view of the substratum. Mobile invertebrates (including rock lobsters, abalone, sea urchins, octopus etc) were counted, as were cryptic fishes (also estimated for size). The maximum shell length of abalone and the carapace length of rock lobsters were measured underwater using vernier callipers whenever possible.
MACROALGAE:-Macroalgae were surveyed at 10 m intervals along the transect line using a 0.25 m quadrat with a grid of 7 wires crossing perpendicularly. Macroalgal cover was assessed by identifying and counting algae species that occurred directly under the 50 (49 plus one corner) grid positions. Values for each species were converted to percentage of the total values for all algal species. Algae were counted in layers, with percent cover of canopy species recorded first, then pushed aside exposing the understorey species for counting.
At each site, 4 x 50m transects were laid at the 5m or 10m depth contour, and fishes, invertebrates (> 2.5 cm) and algae were recorded separately (as described below) by a team of 2 - 3 divers. Details of each site, including the date and GPS location, were recorded.
FISHES:-The density and estimated size-class of fish species within 5 m either side of the 50 m transect line were recorded by a diver (i.e. 50 m x 10 m). This was done by swimming parallel to the transect line (2.5 m away) and recording fish within a 5 m wide lane, on each side of the transect. Size-classes of total fish length were categorised as 25, 50, 75, 100, 125, 150, 200, 250, 300, 350, 375, 400, 500, 625, 750, 875 and 1000+ mm. Lengths of fish >1000 mm length were individually estimated.
MACROINVERTEBRATES:-A diver searched the seabed for a 1 m wide lane along the transect line for cryptic fishes and macroinvertebrates (i.e. 50 m x 1 m). Four 1 m x 50 m transects were surveyed at each site. Algae were swept away from the transect to obtain a clear view of the substratum. Mobile invertebrates (including rock lobsters, abalone, sea urchins, octopus etc) were counted, as were cryptic fishes (also estimated for size). The maximum shell length of abalone and the carapace length of rock lobsters were measured underwater using vernier callipers whenever possible.
MACROALGAE:-Macroalgae were surveyed at 10 m intervals along the transect line using a 0.25 m quadrat with a grid of 7 wires crossing perpendicularly. Macroalgal cover was assessed by identifying and counting algae species that occurred directly under the 50 (49 plus one corner) grid positions. Values for each species were converted to percentage of the total values for all algal species. Algae were counted in layers, with percent cover of canopy species recorded first, then pushed aside exposing the understorey species for counting.
Notes
CreditAustralian Research Council (ARC)
Credit
National Heritage Trust (NHT)
National Heritage Trust (NHT)
Credit
Natural Resource Management (NRM)
Natural Resource Management (NRM)
Credit
Fisheries Research Development Corporation (FRDC)
Fisheries Research Development Corporation (FRDC)
Credit
Professor Colin Buxton
Professor Colin Buxton
Purpose
The initial purpose was to provide a description of the temporal changes in the biota of Tasmanian MPAs following protection from fishing. This was expanded to providing an insight into biogeographical patterns at the Tasmania wide scale. It has since been further expanded to describe biogeographical patterns at an Australia wide scale, to describing temporal changes in MPAs at an Australia wide scale, for understanding natural variability at decadal time scales, detecting changes associated with climate change (range extensions), quantifying impacts of introduced species (e.g. Undaria), understanding and describing ecosystem effects of fishing, and describing the influence of reef based fisheries at the decade scale.
The initial purpose was to provide a description of the temporal changes in the biota of Tasmanian MPAs following protection from fishing. This was expanded to providing an insight into biogeographical patterns at the Tasmania wide scale. It has since been further expanded to describe biogeographical patterns at an Australia wide scale, to describing temporal changes in MPAs at an Australia wide scale, for understanding natural variability at decadal time scales, detecting changes associated with climate change (range extensions), quantifying impacts of introduced species (e.g. Undaria), understanding and describing ecosystem effects of fishing, and describing the influence of reef based fisheries at the decade scale.
Created: 03 07 2007
text: westlimit=147.3; southlimit=-43.07; eastlimit=147.4; northlimit=-43.03
text: uplimit=10; downlimit=5
Subjects
Agricultural and Veterinary Sciences |
ANIMALS/INVERTEBRATES |
Abundance - fish |
Abundance - invertebrates |
Aquatic Ecosystem Studies and Stock Assessment |
BENTHIC HABITAT |
Biological Sciences |
Carapace length - rock lobster |
Conservation and Biodiversity |
Ecology |
Environmental Science and Management |
Environmental Sciences |
FISH |
FISHERIES |
Fisheries Sciences |
Fish size class |
Freshwater Ecology |
MACROALGAE (SEAWEEDS) |
Marine and Estuarine Ecology (Incl. Marine Ichthyology) |
Percentage cover algal species |
REEF HABITAT |
Shell length - abalone |
biota |
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Other Information
global : 24d0bb36-8fae-4bdd-8aaf-8d917d2a81b6
Identifiers
- global : 03c59e36-bee4-4186-8bd4-f1c5dd69c396
