614
W. Judson Kenworthy et al.
B. The Great Barrier Reef: A Representative
Areas Approach for Protecting Biodiversity
Including Seagrasses
1. The Great Barrier Reef Marine Park
Establishing Marine Protected Areas requires careful definition of the location, size, and comprehensive representation of species, habitats, and
ecosystems representative of the biomes protected
by the MPA (Jameson et al., 2002; Lubchenco et al.,
2003). The Great Barrier Reef World Heritage Area
in northeastern Australia is the largest world heritage site covering 347,800 km
2 and stretching along
approximately 2,000 km of coastline in northeastern Australia. It is managed as part of a very large
MPA—the Great Barrier Reef Marine Park. Although it is best known for its approximately 2,800
coral reefs, coral accounts for only about 6% of the
total area. Inter-reef and lagoon areas are far larger
at 61%, with the continental shelf making up the
balance of the area (Lee Long and Thom, 2001;
Wachenfeld et al., 1998). It is also one of the most
important sites in Australia for seagrass biodiversity, with 15 species. Nearly 6,000 km
2 of seagrass
beds grow in water shallower than 15 m and as much
as 40,000 km
2 of seagrass occur in waters deeper
than 15 m (Coles et al., 2000). The GBR is typical
of a vast biome of seagrasses found throughout the
Indo Pacific region and conservation practices in the
GBRMP are a model applicable to other sites in the
region as well as other locations.
When the Great Barrier Reef Marine Park was
established in 1975 it was designed to protect coral
reefs and minimize conflict between users. In highly
protected areas nonreef habitats were severely under represented, including seagrasses. Since 1975
scientific understanding of the significance of interconnectivity across reef and nonreef areas and the
concepts of ecosystem services and protection of
biodiversity have radically changed protected area
management approaches. A review of existing zoning arrangements in the GBR, recently concluded,
has used an approach that identifies and protects representative examples of the biodiversity of habitats
and processes upon which species depend rather than
focusing on individual species or specific habitats.
A representative area is defined as an area that is
typical of the surrounding habitats or ecosystems at
a selected scale (GBRMPA, 1999). This Representative Area Program approach is a departure from
the past of protecting parts of the Marine Park perceived to have a high value, to protecting a range of
habitats that are representative of the biodiversity in
the area. Some areas included in a representative approach will not be perceived by others, such as fisheries agencies and public users of the reef, to have a
high conservation value, yet may exclude them from
some activities in those areas.
To implement a Representative Area Approach
over such a large region a biophysical analysis was
guided by an independent scientific steering committee with an analytical working group providing
modeling, statistical analysis, GIS skills, and general guidance. This process provided conservation
options that were then refined using socio-economic
data and expertise followed by a formal statutory
process which included public consultation. The
three-step process is outlined in Fig. 7. In the classification phase a biological conservation approach
was implemented in two ways. Knowledge was collected by interviews from over 60 experts, most with
scientific expertise, including indigenous and fishing industry people. This “Delphic”-type approach
was combined with about 60 key biophysical data
sets (e.g. seagrass, algae and bottom community, geomorphology, topography, and oceanography) and
with data on special and unique areas in an interactive workshop with GIS overlays and analysis. From
this, 70 bioregions were identified. A bioregion was
defined as an area within which habitats, communities (areas such as seagrass) and physical features
(such as sediment and water depth) would be more
similar to each other than to similar habitats (or communities) occurring in other bioregions (Day et al.,
2000). This process provided a conceptual approach
to understand the heterogeneity of this large system and the basis for designing a reserve network
system—a part of each bioregion would be included
for protection.
2. Highly Protected or No-take Areas
The second phase of selection used the bioregions
and scientific data to select various options for including parts of the Marine Park in highly protected
areas or no-take areas. The identification process
used a modified reserve design software program
MARXAN based on the terrestrial SPEXAN (Ball
and Possingham, 2000), and other tailored analytical
tools (De’arth and Fabricius, 2000). If several configurations of highly protected areas exist that satisfy
W. Judson Kenworthy et al.
B. The Great Barrier Reef: A Representative
Areas Approach for Protecting Biodiversity
Including Seagrasses
1. The Great Barrier Reef Marine Park
Establishing Marine Protected Areas requires careful definition of the location, size, and comprehensive representation of species, habitats, and
ecosystems representative of the biomes protected
by the MPA (Jameson et al., 2002; Lubchenco et al.,
2003). The Great Barrier Reef World Heritage Area
in northeastern Australia is the largest world heritage site covering 347,800 km
2 and stretching along
approximately 2,000 km of coastline in northeastern Australia. It is managed as part of a very large
MPA—the Great Barrier Reef Marine Park. Although it is best known for its approximately 2,800
coral reefs, coral accounts for only about 6% of the
total area. Inter-reef and lagoon areas are far larger
at 61%, with the continental shelf making up the
balance of the area (Lee Long and Thom, 2001;
Wachenfeld et al., 1998). It is also one of the most
important sites in Australia for seagrass biodiversity, with 15 species. Nearly 6,000 km
2 of seagrass
beds grow in water shallower than 15 m and as much
as 40,000 km
2 of seagrass occur in waters deeper
than 15 m (Coles et al., 2000). The GBR is typical
of a vast biome of seagrasses found throughout the
Indo Pacific region and conservation practices in the
GBRMP are a model applicable to other sites in the
region as well as other locations.
When the Great Barrier Reef Marine Park was
established in 1975 it was designed to protect coral
reefs and minimize conflict between users. In highly
protected areas nonreef habitats were severely under represented, including seagrasses. Since 1975
scientific understanding of the significance of interconnectivity across reef and nonreef areas and the
concepts of ecosystem services and protection of
biodiversity have radically changed protected area
management approaches. A review of existing zoning arrangements in the GBR, recently concluded,
has used an approach that identifies and protects representative examples of the biodiversity of habitats
and processes upon which species depend rather than
focusing on individual species or specific habitats.
A representative area is defined as an area that is
typical of the surrounding habitats or ecosystems at
a selected scale (GBRMPA, 1999). This Representative Area Program approach is a departure from
the past of protecting parts of the Marine Park perceived to have a high value, to protecting a range of
habitats that are representative of the biodiversity in
the area. Some areas included in a representative approach will not be perceived by others, such as fisheries agencies and public users of the reef, to have a
high conservation value, yet may exclude them from
some activities in those areas.
To implement a Representative Area Approach
over such a large region a biophysical analysis was
guided by an independent scientific steering committee with an analytical working group providing
modeling, statistical analysis, GIS skills, and general guidance. This process provided conservation
options that were then refined using socio-economic
data and expertise followed by a formal statutory
process which included public consultation. The
three-step process is outlined in Fig. 7. In the classification phase a biological conservation approach
was implemented in two ways. Knowledge was collected by interviews from over 60 experts, most with
scientific expertise, including indigenous and fishing industry people. This “Delphic”-type approach
was combined with about 60 key biophysical data
sets (e.g. seagrass, algae and bottom community, geomorphology, topography, and oceanography) and
with data on special and unique areas in an interactive workshop with GIS overlays and analysis. From
this, 70 bioregions were identified. A bioregion was
defined as an area within which habitats, communities (areas such as seagrass) and physical features
(such as sediment and water depth) would be more
similar to each other than to similar habitats (or communities) occurring in other bioregions (Day et al.,
2000). This process provided a conceptual approach
to understand the heterogeneity of this large system and the basis for designing a reserve network
system—a part of each bioregion would be included
for protection.
2. Highly Protected or No-take Areas
The second phase of selection used the bioregions
and scientific data to select various options for including parts of the Marine Park in highly protected
areas or no-take areas. The identification process
used a modified reserve design software program
MARXAN based on the terrestrial SPEXAN (Ball
and Possingham, 2000), and other tailored analytical
tools (De’arth and Fabricius, 2000). If several configurations of highly protected areas exist that satisfy