FACTSHEET
Marine brown alga
Nereia lophocladia
Fisheries Ecosystems Unit, Port Stephens Fisheries Institute
Description
Nereia lophocladia is one of four species in the
genus Nereia: the others being Nereia filiformis (J.
Agardh) Zanardini from the Mediterranean, Nereia
intricata Yamada from Japan and Hawaii, and
Nereia tropica Taylor from the Galapagos Islands.
Two undescribed species have since been
discovered from Norfolk Island and New
Caledonia. In the evolutionary chain the genus
Nereia is the oldest member of the order
Sporochnales and Nereia lophocladia is the oldest
extant member of the genus.
Habitat and Ecology
Nereia lophocladia is found on rocks at the
sand/rock interface on the seabed in about 5 -7m
depth of water.
Sporophyte of Nereia lophocladia Photo: Alan Millar
Introduction
The marine brown alga, Nereia lophocladia has
only been found in two places on the coast of
Australia; Port Phillip Heads in Victoria and
Muttonbird Island at Coffs Harbour in northern New
South Wales. Despite intensive survey work Nereia
lophocladia has not been found in southern
Australia since the late 1800’s. The population at
Coffs Harbour was discovered in 1980 and is the
only known remaining population of the marine
alga.
Nereia lophocladia was listed as a vulnerable
species in July 2005. However, in 2007 the
Fisheries Scientific Committee reviewed the
conservation status of the species and
subsequently upgraded Nereia lophocladia to a
critically endangered species in NSW. There are
heavy penalties for harming, possessing, buying or
selling it, or for damaging its habitat (see ‘Legal
implications’).
The life cycle of Nereia lophocladia involves an
alternation of generations. The sporophyte (see
photo) releases spores that germinate into free
living microscopic branched creeping filaments
(gametophytes) with separate sexes.
Gametophytes have half the number of
chromosomes of the sporophyte. Sexual
reproduction of the gametophytes results in the
commencement of the sporophyte stage.
Both stages of the life cycle are influenced by the
same environmental factors.
The species is thought to have limited dispersal
capabilities.
Why is Nereia lophocladia threatened?

The reason for the disappearance of Nereia
lophocladia from south-eastern Australia is
unknown. However, a reduction in numbers at
Coffs Harbour has been attributed to the
construction of a breakwall that joins
Muttonbird Island to the mainland.

There is also anecdotal evidence of an
increase in sea urchins that could be causing
June 2012, http://www.dpi.nsw.gov.au/factsheets for updates
Primefact 192 second edition
Aquaculture, Conservation and Marine Parks

large scale grazing pressure on the north side
of the Island.
without approval through such actions as dredging
and construction.
Nereia lophocladia growing at this location is
brilliantly iridescent and is a potential target for
illegal aquarium collection.
The impact of developments or activities that
require consent or approval (in accordance with
the Environmental Planning and Assessment Act
1979) must be assessed and considered by
consent or determining authorities. Where such
actions are likely to result in a significant impact on
a threatened species or its habitat, a detailed
species impact statement must be prepared.
Conservation and recovery actions

Nereia lophocladia grows within a habitat
protection zone of the Solitary Islands Marine
Park on the northern side of Mutton Bird Island.
The zoning plan of the marine park provides a
high level of environmental protection.

Conduct further research into the distribution,
biology and ecology of the species.

Educate aquarium enthusiasts about the
threatened status of Nereia lophocladia and
the ban on collecting the species.

Implement the Protected, Threatened and Pest
Species Sighting Program: Report any
sightings of the species on the NSW DPI 24
hour automated message-taking service by
calling (02) 4916 3877.
Strategies to be adopted for promoting the
recovery of Nereia lophocladia to a position of
viability in nature must be set out in the NSW DPI
Priorities Action Statement.
A recovery plan may be prepared for in
accordance with the provisions of the Fisheries
Management Act 1994 to promote the recovery of
the species to a position of viability in nature.
Bibliography and further reading
Fisheries Scientific Committee 2007. Final
Determination, Nereia lophocladia Marine
brown alga.
Yee N, Millar AJK, Marchant A and Peters A. 2003.
Phylogenetic relationships between genera of
the Sporochnales (Phaeophyceae) as inferred
from plastic DNA sequences. 3rd European
Phycological Congress.
For further information
Contact NSW DPI Threatened Species Section.
Port Stephens Fisheries Institute
Locked Bag 1
Nelson Bay NSW 2315
Fax (02) 4916 3880
Email:[email protected]
Distribution of Nereia lophocladia in NSW.
Legal implications
It is illegal to collect and keep, buy, sell, possess or
harm Nereia lophocladia (or any other threatened
species in NSW) without a specific permit, licence
or other appropriate approval, and significant
penalties apply. For critically endangered species
these penalties can include fines of up to $220,000
and up to 2 years in prison.
There can also be significant penalties for causing
damage to the habitat of a threatened species
p 2 Nereia lophocladia Marine brown alga
© State of New South Wales through Department of Trade and
Investment, Regional Infrastructure and Services 2012. You
may copy, distribute and otherwise freely deal with this
publication for any purpose, provided that you attribute the
Department of Trade and Investment, Regional Infrastructure
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ISSN 1832-6668
Disclaimer: The information contained in this publication is
based on knowledge and understanding at the time of writing
(June 2012). However, because of advances in knowledge,
users are reminded of the need to ensure that information upon
which they rely is up to date and to check currency of the
information with the appropriate officer of the Department of
Primary Industries or the user’s independent adviser.
Published by the Department of Primary Industries, a part of the
Department of Trade and Investment, Regional Infrastructure
and Services.
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