marine habitats are those found on the sea floor (benthic
means "bottom"). They are made up mainly by
macroalgae (plants) but also some sessile (attached)
invertebrates. Two survey methods are used to sample
Intercept Transect (LIT) - a weighted one metre steel
ruler is placed in a number of consecutive locations
on a bottom contour and the points along one edge
(in cm) at which the lifeforms change are recorded.
This is the same method used in studies commissioned
every few years by the EPA. The method used is described
more fully in the Reef
Watch LIT Survey Manual, which should be read
in conjunction with the Reef
Watch Site Manual.
- a one square metre quadrat is placed randomly on
the bottom and the approximate percentage cover and/or
count of the different lifeforms within it are recorded
using codes. The method is described more fully in
Watch Quadrat Survey Manual.
Datasheets for both Quadrat and LIT surveys are available
from Reef Watch, but if you have waterproof paper
you can download and print your own:
that there are more than a thousand species of algae,
and that even the experts can't identify them all without
laboratory equipment, Reef Watch provides a simple yet
scientifically useful set of lifeform codes that are
based on appearance. The same codes are used for both
codes are described in the Reef
Watch Benthic Identification Manual.
benthic identification manual is best read with the
book Australian Marine Life - The Plants
and Animals of Temperate Waters, by Graham Edgar
(either the first edition by Reed books in 1997, or
the second, paperback edition by Reed New Holland in
2000 will do). Although it contains only a relatively
small proportion of the known southern Australian benthic
species, it covers those most commonly observed by divers.
Graham has generously allowed us to use images from
this book for our on-line identification guides and
is a list of Reef Watch and other resources that can
assist you with the identification of benthic organisms
(both algae and invertebrates), and provide further
|List of codes for species
in Australian Marine Life
|Illustrated identification guides
|Other web sites
Life Society of South Australia (MLSSA) -
- a database of information on algae, including
names and images.
Seaweed Site - information on marine algal
Australian Marine Life,
by Graham Edgar (see above)
Plants of Australia, by John Huisman, 2000,
University of WA Press.
||Sets of herbarium sheets with identification notes
are readily accessible to the public in the reception
area at the SA Herbarium on Hackney Road.