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PART-IV Discussion:
Papua New Guinea (PNG) is the largest equatorial island and lies adjacent to the northern tip of the
Great Barrier Reef. The southern reefs of Papua New Guinea are a continuation of the GBR, whereas the reefs to the north and
around the islands have strong affinities with reefs of the Solomon Islands to the east and Indonesia to the west. |
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Coral reefs are an integral part of the subsistence economy in most coastal regions where people rely
on them for coastal protection, food, medicines and cultural properties. Subsistence and artisinal (or game) fishing is the
predominant human activity on PNG reefs. In general, reef fish harvests are thought to be below sustainable levels. The
pressures on reef resources in PNG will almost certainly increase as the population continues to grow, especially in large
coastal towns, along with a growing tourism industry. The national economy is poorly developed although the islands are
rich in resources and foreign aid plays a major role in this economy. |
![]() Echinopora sp. (Pectiniidae - 185kB) |
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An ecological assessment of Milne Bay Province noted that the bay is separated from the open sea by a
barrier reef with both sunken and exposed portions (Opu and Aruga 1999). The diverse coastal habitat of this bay includes
seagrass meadows, mangroves, sandy beaches and coral reefs. Its coral reefs are characterized by high species diversity. For
example, 1,039 species of fish and 637 species of molluscs were recorded in a recent survey in Milne Bay Province (Werner,
and Allen, 1998) along with 362 species of hard coral (Veron 1997) with a live coral cover of up to 83%. He discovered 14 new
species and predicted that the total number of coral species could approach 420 - including the free-living hermatype
Heteropsammia. Indeed an average coral coverage over 40% is common, but this varies with location, reef type, depth
and other variables. In comparison, the average reef-wide cover of hard coral on GBR was estimated at 23% in 2000,with values
ranging from 3-51%. These relatively low values reflect fairly frequent disturbances such as cyclones and Crown of Thorns (CoT =
Acanthaster planci) outbreaks during the last few decades. Much of the change in coral cover on the GBR is due to
growth and destruction of table Acropora spp. (e.g. A.cytherea and A.hyacinthus). These table corals live
in areas of high water movement and grow rapidly to cover a large area, but they become increasingly susceptible to storm
damage as they grow. On reefs close to the equator, where cyclones are rare, such corals cover much of the reef and average
values for coral cover will be higher (up to 80% or more in places - Maniwavie et al. 2000). |
![]() Montipora sp. probably M.danae (Acroporidae - 255kB)
![]() Platygyra lamellina (Faviidae - 215kB)
![]() Lobophyllia hemprichii (Mussidae - 210kB) |
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Threats: Some of the most serious threats to coral reefs in PNG appear to come from terrestrial
activities, such as sediment mobilisation as a result of large-scale forestry and agriculture. Extensive tracts of coastal forest
have been allocated for logging and there are insufficient mechanisms to prevent widespread sediment damage to reefs as a
consequence. Given that most of PNG reefs are nearshore and downstream of steep, forested watersheds, then significant
additional inputs of sediments can be expected from large-scale deforestation. Although there are almost no data to substantiate
elevated sedimentation as a result of past or current logging operations, there is equally no quantitative monitoring of reefs that
might be affected by these logging activities. Increasing stresses on reefs will also come from the growing coastal population
and pattern of urbanisation, though increased fishing pressure and pollution, such as inadequately treated sewage. Attempts to
assess anthropogenic impacts to coral reefs in PNG are limited by a lack of data on the spatial and temporal patterns on the
abundances of reef organisms and a lack of data on the physical and chemical characteristics of the reef environment. The
apparent good condition of PNG reefs must, therefore, be considered with this lack of information in mind. Reliable monitoring
programs should be encouraged, particularly in areas of increasing population pressure and where anthropogenic impacts are
likely to occur in the future. |
![]() Acropora palifera (Acroporidae - 255kB)
![]() Acropora sp. probably A.cytherea ( Acroporidae - 215kB) |
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Monitoring Change in Tropical Marine Biota: Healthy coral reefs are one of the most exotic and
varied habitats known to us, but they also pose problems for conservationists. In order to predict coastal marine habitats, it is
essential to know about its past, to understand the bio-geochemical connectivity, and the dynamics of destabilizing processes.
Coral reefs may be temporarily damaged by natural events such as hurricanes (although rare), temperature and salinity changes,
sedimentation, and a host of biological factors, but many of the most serious and lasting threats come from man himself. Humans
tend to consider the sea both as a convenient dumping site as well as a useful provider. Coral reefs are exploited for food,
trophies and building material. They are abused by dynamite and other destructive fishing methods. They are choked by silt
washed into the sea from erosion on land, or are disturbed during dredging operations or sand extractions in shallow waters.
They are polluted by sewage, oil, pesticides, industrial wastes, and are damaged by warm water outflows. Along the coast of
Papua New Guinea, the amount of river water and sediment transported into the ocean - especially during the monsoon season -
is very large. Satellite based remote sensing technology can be used to map and monitor shallow water habitats (Quinn et
al.1985, 1986).With the help of such data, it is also possible to trace river plumes, and relevant information important to
understand marine bio-geochemistry. Rain, especially, in the wet season, washes fertilizers and pesticides into the river,
industries may spill part of their waste, increased development replaces dense vegetation with concrete and bare soil, causing
increased erosion and ultimately increased sedimentation and eutrophication. Layers of marine sediment, accumulated through
time, store data of changing land use through history. Researchers are studying patterns of coral reef growth and linking
historical climatic records with current information and creating models of climate change through time. The last 200 years can
be tracked by the researchers examining coastal sediments, and signatures of climate change as well as contaminants that are
incorporated into growing coral skeletons. Researchers can read the history of land use and climate change over the last
several centuries that are recorded in the annual growth bands of massive corals. Such information aids in the understanding of
the periodicity of ENSO related drought and flood events, climate change, and to detail the pathways of carbon cycles and
ocean water circulation. Such findings allow researchers to link present assessments of ecosystem sensitivity to climate
variations with the potential effects of climate changes in the future. In this way oceanography is linked to biology, and also to
industry (it helps to assess the risk and dispersal of oil spills, pesticides and other organic wastes in the environment or creates
more effective strategies of rescue efforts. In addition, such study enables the classification of an ecosystem's stability and its
capability to resist outside disturbances). It also helps to understand the influence of wave and tide-induced flushing currents on
larval dispersal (how tidally generated internal waves effect vertical and horizontal movement of phytoplankton, as well as the
mixing of phytoplankton and other nutrients which occurs). Thus, facilitating prediction of larval dispersal of crown-of-thorns
starfish. |
![]() right: Acropora sp. probably A.eyquisita (Acroporidae); left: Pachyseris speciosa (Agarticiidae - 190kB) (Acroporidae - 255kB)
![]() Echinopora sp. (Faviidae - 165kB)
![]() Goniastrea sp. (Faviidae - 185kB)
![]() Acropora palifera (Acroporidae - 180kB) |
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PNG Legislation and Regulation: There appears to be adequate laws and legislation for the conservation and management of coral reefs. However, most legislation does not specifically refer to marine systems and this has caused uncertainty about how it should be applied to coral reefs. Also, the laws relevant to different sectors (e.g. fisheries, mining, environmental protection) are not fully integrated which has lead to confusion over which laws have priority, who is responsible for management, and the rights of the various interest groups. There is little government capacity for enforcement of laws, quota and regulations. A national surveillance strategy has been suggested which would involve participation from all levels of government, NGOs and local communities. Local communities have to play a greater role in enforcement of fisheries regulations and marine protected area through the expansion of community based management programs. |
![]() Montipora sp. (Acroporidae - 190kB) |
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Management Concepts: The unrivaled cultural and natural attractions of the province's marine
environment does have huge tourism potentials, and are already a popular dive destination. Due to ancestral ownership by
fishing villagers of Milne Bay Province, financial compensation by visiting dive boats should be given to the locals. They also
should be offered the chance to participate in management projects, in order to avoid missuse in form of cyanide and dynamite
fishing and the illegal exploitation of giant clams. Any license issued for the purpose of reef fishing should specifically ban the
use of such degrading methods, with any commercial fishing activity accurately monitored by a provincial officer that should
monitor ongoing activities aboard. Excess harvesting and removal of protected species should result in a fine, seizure of the
vessel, and immediate withdrawal of the license. |
![]() Acanthastrea sp. probably A.ishigakiensis or A.hillae (Mussidae - 235kB)
![]() Mycedium sp. or Echinophyllia aspera (Pectiniidae - 205kB) |
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Marine Park Authorities: PNG has a number of legally designated protected areas that contain coastal and marine habitats within their boundaries. However, insufficient resources for management and enforcement of regulations means the effectiveness of these areas is usually questionable. There are, however, demonstrated successes in the small-scale, community-based protected areas in a number of locations. Currently the most effective marine protected areas in the country are in Kimbe Bay, Madang, and Aroma coast. They provide a model of how other protected areas can be established and managed. Milne Bay province is a priority region for new protected areas, given that it contains much of PNG reef area, the highest overall diversity of fishes and other marine organisms, and most of the endemic species of fish. It appears that the ingredients for success in these areas include:
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![]() top: Favites sp. (Faviidae); bottom: Euphyllia sp. probably E.cristata (Euphyllidae - 180kB)
![]() Porites sp. (Poritidae) with Octopus (211kB) |
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Recommendations: A number of recommendations are made for ways to support efforts to protect and conserve coral reefs in PNG, some of which are already being developed or instigated (Suggestions based on the management concepts of P.L.Munday's The Status of Coral Reefs in PNG, 2000) Building Scientific Capacity for both the long-term assessment and management programs: Effective management of urban development, watershed degradation and large-scale commercial activities requires much greater capacity in provincial and national government agencies.
Improving knowledge: Monitoring initiatives need to be supported and developed to provide an effective and ongoing assessment of reef health - especially in areas likely to come under stress from coastal development and other terrestrial activities. Support is needed for diver and technical skills training, routine monitoring trips, quality control, data assessment and dissemination; High quality mapping of PNG reefs is important for conservation initiatives and appropriate management of fisheries and biodiversity assessments for the long-term sustainability of PNG’s coral reef resources.
Implementation of Marine Protected Areas: Community-based programs could be established within a network of marine protected areas. Addressing the needs of local communities and integrating them in the development, management and enforcement of protected areas is likely to yield success. Continued community support is important for the success of marine protected areas.
Threats to Reefs: Effective methods of enforcing fisheries regulations are urgently needed. This is particularly important for any re-introduction of the live reef-fish trade.
Awareness and Education: Community education and alternative income programs can help reduce destructive fishing practices. Increased commitment is also needed at provincial and national levels.
Many of these recommendations focus on specific issues or are community based. A number of other issues such as urban development - here especially the provincial capital of Alotau, watershed degradation and large-scale commercial activities require a more integrated approach that will depend on improved capacity in both provincial and national government agencies. Finding ways to increase the importance of environmental issues at higher policy levels will clearly bring substantial rewards to conservation efforts. |
![]() left overview: Platygyra sinensis on top with Echinopora mammiformis (right) and probably Millepora sp. (left); detail right: Platygyra sinensis with Porites sp. (Faviidae / Poritidae - 155kB)
![]() overview: Diploastrea heliopora (Faviidae) with Porites sp. (Poritidae) below; detail: D.heliopora (185kB)
![]() overview: members of the family Acroporidae; detail: Acropora willisae on top and A.sp. (hyacinthus group) below (235kB)
![]() top: Protopalythoa sp. (Zoanthidae) surrounded by an encrusting sponge; bottom: either Scolymia sp. or Lobophyllia pachysepta (Mussidae - 265kB) |
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Literature: Gosliner, T.M., Behrens, D.W., Williams, G.C.; 1996; Coral Reef Animals of the Indo-Pacific; Sea Challengers; California - USA. Halstead B., 1997; The Dive Sites of PNG; Passport Books - NTC Publishing Company; Chicago, IL - USA. March L., Slack-Smith S. 1986; Sea Stingers; Western Australian Museum, Perth - AUS Pears V.&J.; Buchsbaum M. & R.; 1986; Living Invertebrates; Boxwood Publishers, Los Angeles , CA - USA. Schumacher H.; 1976, Korallenriffe; BLV-Verlagsgesellschaft München - FRG Tomascik T., Mah A.J., Nontji A., Moosa M.K.; 1997; The Ecology of Indonesian Seas - Part I; Oxford University Press - Singapore. Veron, J.E.N; 1997; Corals of Australia and the Indo-Pacific; University of Hawaii Press, Honolulu, USA. Veron, J.E.N. 2000; Corals of the World; Australian Institute of Marine Science; Townsville - AUS. Werner T.B., Allen G.R. eds. 1998; A rapid biodiversity assessment of the coral reefs of Milne Bay Province, PNG; Rapid Assessment Program, RAP Working Papers 11; Conservation International; Washington DC - USA http://www.conservation.org/marine/diverse.htm Wood E.M. 1983; Corals of the World; TFH Publications Inc Ltd - USA Wood R.; 1999; Reef Evolution; Oxford University Press; New York - USA Recent AIMS Report sheets: Human Impacts on Coastal Marine Ecology; Marine Biogeochemistry of Contaminants; Marine Bioproducts; Monitoring Change in Tropical Marine Biota; Predicting the Coastal Marine Environment; Supporting Tropical Fisheries; Sustaining Coral Reefs; Sport Diving Australia Magazine #77, Nov-Dec 1999-2000 Coral Reef Research Center: http://www.reef.crc.org.au/ Great Barrier Reef Marine Park authority: http://www.gbrmpa.gov.au/ M.V.Marlin1: http://www.png-diveboat.com/boat.html Reef Teach Center (Paddy Colwell); Cairns - AUS: http://www.reefteach.com.au/ ReefBase - A Global Information System On Coral Reefs: http://www.reefbase.org/Summaries/default.htm http://www.reefbase.org/Summaries/National81.htm Porifera: http://www.mailbase.ac.uk/lists/porifera/ http://www.divewhidbey.com/sealife.htm | |
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