Contribution for the 28th BUFUS Newsletter
Contact the Authors (Madl & Yip)
....I'll never get tired to gaze at the sheer unlimited diversity of life,
Girl w/ grandma in boat (80kB)
Our planet faces many serious environmental problems, among them global climate change, land
degradation, soil erosion and pollution of the biosphere. There is though an even more serious problem that surpasses all others
in term of importance - loss of biodiversity (extinction of species), as the most severe and irreversible consequence.
Around the world, humans are responsible for a worsening trend of net loss in the amount of "untouched", natural habitats that
cover our planet. Even though the working groups involved in this excursion are no specialists in their assigned field, it was still
our aim to identify as many organisms as possible (although, the sheer amount of organimic diversity just flooded both our eyes
and recognition). The manifold display of live present on these reefs becomes even more valuable if we consider that many of
them are lost even before scientists had a chance to document the rich array of organisms that thrive in our biosphere and
determine their potential benefit to human kind; perhaps as sources for new medical treatments or economic livelihood.
At a global level, there are roughly 25 regional land areas that account for 40% or more of all terrestrial diversity which are at
great risk (see also threats to reefs).
PNG's geographical setting:
PNG is part of the "coral triangle" that comprises countries like Indonesia, Malaysia, Japan and Australia.
It houses the most biological diverse coral reefs, mangroves, and sea grass beds in the world.
Map of PNG & milne bay (140kB)
There are innumerable fringing, platform and bank reefs, some small barrier reefs and a few atoll-like
formations. The reef life is extremely rich and diverse, and the area is generally considered as one of the faunistic center of the
entire Indo-Pacific region.
Oil Search Limited operating in the PNG highlands (175kB)
Physical environment: The climate is monsoonal, tropical, with much of the year being hot, still,
and humid. During November to March a prevailing westerly and north-westerly rain-bearing monsoon dominates, while a dry
south-easterly trade winds become evident from May to September.
Reef morphology: Four major types of reef structures are present in Milne Bay Province; fringing
reefs, platform reefs, atolls, and barrier reefs.
Reef types of PNG (75kB)
Deacons Reef and Dinah's Beach: Deacon's reef comprises of a steep drop-off that
easily exceeds the 100m mark. Being close to the shore, a series of coral towers reach almost the water surface where they
easily could come into contact with the overhanging branches of shoreside trees. Besides exquisite coral growth, this site
offered also a large display of sea fans (Gorgonaria), whips (Antipathes and Cirripathes), and large
Tubastrea colonies that are even accessable to snorkelers.
Part of Deacon's Reef with Dina's beach (110kB)
Banana Bommie*: This outer patch reef environment is just small enough to swim around on a single tank, but it is best to dive only whichever side is receiving the current (usually the west). The reef is incredibly rich, and the sheer numbers of marine life are staggering. The reef top houses large numbers of staghorn corals (Acropora), while the reef-side vertically slopes down to the sandy bottom at about 27m. Among garden eels (Gorgasia) also Heteroconger are easily recognized; furthermore, there are batfish (Platax tiera), gray reef shark (Carcharinus amblyrhynchos), colorful red-lined sea cucumbers, masses of small fish (Chromis ternatensis, Pseudoanthias huchtii) and much more.
Boia-Boia Waga: A reef with a huge dropoff that plunges to depths of 40-50m; it displays a large selection of soft corals (Alcyoniidae), sponges, tunicates, crinoids, black corals, small seafans, etc. Turtles are quite common in this area as well. The lagoon area with its impressive thickets of staghorn (Acropora) and some outstanding bommies* form a heaven for thousands of cardinalfishes (Apogon). Even though some claim that it features manta rays (Manta birostris) and Hammerhead sharks (Sphyrna lewini), none of these species have been sighted on our visits.
Black and Silver Reef: It is an outer patch reef environment consisting mostly of large, circular pinnacles with 6-8m on top of the reef and dropping steeply - almost vertically into deep water. Besides a very large concentration of fish along the slopes (due to strong currents and numerous hiding places), it also has an abundant aggregation of black coral (Cirripathes), anglefish (Genicanthus lamarcki), large amounts of Tubastrea corals, and a splendid display of the larger sponges like (Xestospongia, Speciospongia), besides many different species of sea squirts (Ascidiacea).
Little China Reef: It lies west of Nuakata Island and is a very pretty reef with lots of colorful corals and fish; a place where white tip reef sharks (Trianedon obesus), the Maori wrasse (Cheilinus undulatus), and large barracudas (Sphyranea barracuda) are quite common. This is a relatively sheltered and shallow reef that drops off gently at a roughly 45° angle. Rich corals in shallow waters, predominantly Acropora, and patchy growth along the slopes characterize this site. Sand and scattered bommies* dominate below the 20m line.(*) a coral bommy is a patch reef structure probably the size of a reasonably big house.
Observation Point: A coastal lagoon environment that both combines coral reef, with sea-grass (Enhalus acoroides) and crocodile infested mangroves; it borders a steep sandy slope dotted with crinoids and coral debris. Although less spectacular, and at certain spots partly dead, it offers some very unusual marine life that range from Padina algae to sand darters (Trichonotus halstead). On the other side of the strait, some very active coral predation by Crown of thorn starfish ( Acanthaster planci) can be observed.
Observation Point (140kB)
Mapamoiwa: A silty coastal reef with very few fish species, but in large numbers, small massive coral colonies (Porites sp.) that exhibit a wide variety of color patterns. Apart from the occasionally passing sharks, this reef features not only a very deep dropoff but at the leeward side a rich display of soft, stony corals, and huge barrel sponges (Xestospongia testudinaria), besides a very rich fauna of higher invertebrates.
Barrier Island situated between Goodenough and Ferguson Island, stuns not only a trained diver but makes even a firm snorkeler forget to breathe (!); this very shallow reef impresses with the large display of octocorallia (like Dendronephytha sp.), an impressive variety of nudibranches (among them Notodoris sp., Phyllidia sp.), lobsters (Panulirus sp.), impressive giant clams (Tridacna gigas), numerous rays (Taeniura lymnia), sea turtles (Chelonia mydas) are among the most obvious, must capture even the saturated biologists.
Ferguson Reef, likewise located between Goodenough and Ferguson Island is somewhat less spectacular than the previous site, but houses large areas of corallinacean algea (like Halimeda), and an immense aggregation of foraminifera (probably Marginopora), which offer a superb insight into the frame-building network of a coral reef. A rather dense accumulation of soft corals (Dendronephthy sp., Sarcophyton sp., Xenia sp. etc.) are indicators of sedimentation that probably occur regularly at this site.
Julian's Reef is one of the many reefs to the west of Normanbay Island and lies just north of the small Duchess Island. It has a beautiful scenic reef with very rich hard and soft corals, fans, crinoids and lots of interesting gutters and gullies to explore. There is a ledge on the western side about 20m and about 10m wide, as well as a wall dropping down to 60m or more. Many varieties of fish life; e.g. brown-spotted cat-shark (Chiloscyllium), toadfish (Arothon hispidus), butterfly fish (Chaetodon), and triggerfish (Balistoides), large moray eels (Gymnothorax), and the dreadful crown of thorns (Acanthaster planci). After traversing the NE corner it is possible to return to the boat by way of a small channel where huge colonies of cabbage corals (most likely Turbinaria) are growing.
Aim of this excursions:
Initially, the various working groups were given different phyla to work with: annelids, echinodermata, scolicidae, molluscs, crustacea, chordata, pisces; our group was given the task to document the manifold diversity of porifera (sponges), cnidaria (also known as coelenterates like hydroids, jellyfish, corals sea anemones and black corals) and whenever possible to document the presence of bryozoa (moss animals).