Mangroves lecture.rtf by tongxiamy


									MANGROVES: a fascinating eco-system

REDO THIS LAST PORTION!!! (4. Text mangroves)
The Kamoro distinguish between three different species of pandanus for which we have been unable
to find the scientific names. The most important is a kind they call mani, which bears a large, red
fruit. This is eaten with sago and much appreciated for its oily quality. Another kind, called katang,
is used as tongues to pull things out of fires after they have been cooked. The yapinako kind of
pandanus has wide leaves which are plaited to form temporary shelters.

Mangroves make up a unique eco-system, one of the most unusual on earth. The production of
organic matter is absolutely fantastic: 20 tons of leaves per hectare per year or 1.2 kg. per meter
square. The decaying organic matter starts the rich food chain by breaking down into small particles
called detritus which are then covered by hungry but protein-rich bacteria, along with fungi. These
minute particles feed the mollusks and some of the smaller crustaceans. The chain links up to the
birds, fish, reptiles and mammals. Perhaps even more important, mangroves bind the loose mud, thus
preventing coastal and riverside erosion. Mangroves act as a crucial nursery for many commercial
species such as prawns, mangrove crabs, barramundi, snappers, bream and mackerel. Smaller non-
commercial species spend their juvenile stage in the protective root system of the mangroves, later
becoming food for larger fish.

Mangroves prefer at least a measure of protection from direct contact with waves, on sheltered
shores and between the mean sea level and the mean high water spring tide. Rarely exposed to the
open ocean, mangroves prefer a habitat of abundant silt brought down by rivers, lots of mud.
Mangrove heaven consists of numerous meandering river channels forming a network of waterways
confining the tides. A good description of the south coast of Irian Jaya.

>Mangrove adaptations
Thriving in the coastal tidal swamps, the mangrove vegetation has developed the amazing ability to
absorb and excrete salt water, setting them apart from other plants. Not many made the grade: only
some 55 species world-wide, divided into twenty families. Whereas a square kilometer of tropical
rain forest may contain thousands of plant species, a similar area in the typical mangrove swamp
holds only a couple of dozen different trees and shrubs.

Southern Irian Jaya, the world’s center of mangrove bio-diversity, boasts of just 33 species, divided
into 14 genera and 13 families. These few species, a specialized minority within the different
families, came up with similar adaptations through a process called convergent evolution. As a
parallel in the world of mammals, we have the similar independent evolution of two completely
unrelated species: the placental and marsupial ‘wolves’ with similar bodies, teeth and digestive
systems to nail down a top predator status among carnivores. Yet their birth mechanisms are quite

The mangroves swamps’ high salinity and anaerobic (lacking oxygen) soils required several
physiological evolutionary strategies for survival. A system of aerial roots or else pneumatophores
(horizontal root segments sticking up above the substrate) specialize in absorbing oxygen from the

air and provide stability in the shifting mud. To remove excess salt, some species have evolved salt-
secreting glands while others can survive with their saps holding ten times the salt concentration of
non-mangrove plants.

Aside from their salt-tolerance, most mangroves have developed the advanced reproductive strategy
of seed germination prior to parental release - like almost all mammals. Biologists call this vivipary
or live birth. Some 85% of the mangroves are hermaphrodites, with stamen and carpels in the same
flower. While this makes fertilization a cinch, the cost is diminished genetic diversity. Of the other
mangroves, 11% are dioeceous (male and female flowers on the same plant) and only 4% are
dioeceous where male and female flowers are on different plants. These last two categories need an
outside agent for fertilization. This is where the birds and the bees come in. And bats too.

In a famous case of interlocking dependencies in an eco-system, the delicious (or infamous,
according to your proclivities) durian fruit trees became sickly and would not reproduce in areas of
Malaysia and Kalimantan. For many Asians, this was on the verge of an international disaster.
Biologists to the rescue. Our scientific friends found that a small bat (like the ones at Goa Lawah on
Bali) played a crucial role in during cross pollination. But when the durian flowers were out of
season, the bats fed on the nectar of the Sonneratia, a mangrove genus. When large areas of
mangroves were cleared to make room for fish ponds and other projects, the Sonneratia were cut
down. The bats could no longer feed for several months a year and died or moved. No more durian
pollinators. Tragedy was averted only when it was found the durian could be cross-pollinated by
human hands - but this is a painstaking and not very efficient method. Better leave this to the
nature’s experts, the bats.

Most seeds germinate only if they land on suitable soil - otherwise they lie dormant or die.
Mangrove seeds not only germinate on the parent tree but the seed also grows from the base of the
fruit into an elongated cylinder called a propagule. When finally released, the propagules are adapted
to the saline environment, meaning that they can drift with the tides until sensing a suitable substrate
where, with unseemingly haste, the propagules set out roots before another tide sweeps them away.

>Ecological tragedy
The world total of mangroves is estimated at 18 million hectares using remote sensing technology.
Indonesia is blessed with the most extensive mangroves swamps of any country. But where in 1982
there were some 4.3 million hectares, the 1996 total was down to 3.5 million. This still ranks
Indonesia as numero uno, way ahead of Brazil with 1.4 million hectares and Australia with 1.1
million hectares. Of Java’s former 170,000 hactares of mangoves, 89% has been lost, directly
attributed to change to tambaks (fish and shrimp ponds) which now cover 128,740 ha. Some 70%
of Indonesia’s mangroves are in Irian Jaya.

Most of the loss of Indonesia’s mangroves can be attributed to the lack of ecological awareness in
general and the ignorance or disregard of the function of mangroves in particular. Just about all the
formerly extensive mangrove fringe of north Java has been cut to make way for shrimp ponds,
chopped down for firewood or otherwise destroyed in the name of progress. This is also applies to
large chunks of Kalimantan, Sulawesi and Sumatra. As a direct result, thriving offshore fishing and
shrimp gathering have been eradicated.

Indonesia’s most extensive remaining mangroves swamps stretch along the south coast of Irian Jaya,
split between a 1300-kilometer zone along the Arafura Sea from near the border with Papua New
Guinea to Etna Bay, and then farther west, in Bintuni Bay. Unfortunately, a large chunk of Bintuni
Bay’s mangroves have been devastated to feed a large Japanese-Indonesian wood chip plant which
sends its output to Japan to make paper, cardboard and rayon. Other lumber companies around
Bintuni, even if they do not specialize in mangroves, have also greatly disturbed large areas due to
careless operations and infrastructure.

>Animals in the mangrove supermarket
The mangrove swamps hold many more useful animals than the hordes of mosquitoes - which
however seldom bother humans in a moving boat. The many edible animals found here by the local
inhabitants turn this area into a vast, free supermarket. One just needs skill and experience as to just
where to shop. And when: the timing of the tides determines the shopping hours.

Mollusks are abundant in the mangroves, especially various snail-like gastropods and bivalves which
include the tambelo. This long, thick, worm-like animal, closely related to ships’ worms, is really a
bivalve mollusk, living in two species of mangrove trees. Repulsive to most outsiders, the tambelo is
a delicacy to the Kamoro. It is usually eaten raw, right on the spot as the animal is pulled out of the
split mangrove tree. Some of the tambelo as well as other mollusks larger than a couple of
centimeters are brought back by the ladies from their daily shopping trip in the mangroves, an
adjunct to the family meals. No market exists for mollusks, thus consumption is limited to the

Quite the contrary for crustaceans. A high demand exists, especially in Timika, an insatiable market
for any of the larger shrimp and the mangrove crab. Some of these crabs have been exported, by air,
to Singapore as they can stay alive for several days. Mangroves are home to many other crab
species, including the often seen fiddlers with one outsized claw, and the sarsamids, eaten locally by
the Kamoro. The mud lobster lives in underground burrows, aerating the soil and thus enhancing the
growth of the vegetation. Their burrows are topped by cone-shaped mounds.

These mounds sometimes serve as a base for the dome-shaped nests of the secretive mangrove pitta
(Pitta megaryncha), much sought after by bird watchers. Other birds include the typical wetlands
denizens like the egret, heron and the cormorant. Along the beach fringe of the mangroves, the
maleo, a mound-building megapode, unwillingly provides outsized eggs to the Kamoro who also
hunt the bird for its meat. At the drier fringes of the mangroves, we find the birds most hunted by
the Kamoro: the cassowary (the largest animal indigenous to Irian), the crown pigeon and the greater
bird of paradise. Numerous hornbills (Blyth’s, the only species in New Guinea) also inhabit this
(Note: material to be added from Peter Ebsworth on the most common and most unusual of
mangrove birds.)


The brackish waters of the mangrove provide a safe haven for many commercial fish species such as
snappers, catfish and the highly prized barramundi. Many other kinds of fish also live there,
temporarily or permanently, the smaller ones prey for the commercial species in the estuaries, the
inland water network and the offshore waters. Two unusual fish also inhabit the mangroves. The
frequently seen mudskippers can spend long periods out of the water thanks to a breathing apparatus
partially adapted for air, along with modified fins for skipping along the mud and even climbing a
short way up the nearby plants in search of insects. The archer fish uses a different technique for his
meals: an accurate gob of water spat out from under the surface to nail a nearby unsuspecting insect
who deserved to die anyway.

Scientists working in the mangroves subscribe to the motto ‘the only good mozzie is a dead mozzie’.
Not much love is lost either on the aggressive tailor ants. All humans feel much more friendly
towards the synchronous fireflies (a kind of beetle) and their frequent night-time light shows which
illuminate selected trees with precise twinkling - a spectacular show-stopper on pitch-black nights.
Two other kinds of beetles work the opposite fringes of the mangrove swamps. The huge rhinoceros
beetle haunt and severely damage coconut trees growing on the beech-strip. At the opposite side of
the mangroves, the sago grub (a beetle larva) is a sought-after delicacy for the Kamoro while for the
Asmat these fat grubs are both a gourmet delicacy and a ritual food.

The technique of obtaining the grubs is a simple one: cut down a sago tree and return in about three
months. Unless your luck has run way out, the fat, juicy wiggly little white fellows should be happily
munching away. They can be eaten raw, held by the angry head (which can bite back) which is
bitten off and thrown away. A buttery, still-squirming taste. The more squeamish prefer their sago
grubs holding still and roasted. But even this way, few visitors take up the gastronomic challenge to
eat one.

The same technique, the cutting down of a sago tree, also serves to attract the Kamoros’ favorite
protein: wild pig. The trunk has to be split open, but then the wait is much shorter, or there is no sago
tree left - or pigs either. A week is enough. Armed with long spears ending with locally made metal
tips (often forged from Freeport scrap metal), the men and their hunting dogs run down the sago-
satiated animals. Other prey in the mangroves includes various species cuscus, a kind of thick-
furred tree dwelling marsupial, wallabies, and tree kangaroos. Seldom hunted and quite rare, the
long-beaked echidna - an egg-laying marsupial mammal, occasionally roams Irian’s mangroves.
Crab-eating, outsized water rats and crab-eating macaques (not found in Irian) also live and love in
the mangroves. Another mangrove monkey, a Kalimantan endemic called the proboscis, due to its
indecently sized nose, has been dubbed monyet Belanda, the Dutch monkey. The large Dutch noses
attracted plenty of attention among the Indonesians whose noses tend to be short and flat. The
proboscis eats mangrove leaves, processing the vegetation in its digestive tract’s specialized
fermentation chamber - which finds a parallel convergent evolution among the ruminants such as
cows, buffaloes and deer. Large aggregations of flying foxes round out our tally of mangrove
mammals. Spending their days hanging upside down by the hundreds in selected trees, they are easy
prey to the Kamoros’ arrows. At sundown each day, the flying foxes take off to feed, mostly on fruit.


The huge salt-water crocodiles, along with their fresh-water relatives, formerly lurked in large
numbers in the mangroves along Irian’s south coast. In the Asmat area, a seven-meter long monster
was finally destroyed in 1970 after being accused of gobbling 55 humans and countless dogs. After
World War II, professional hunters with high-powered rifles, along with the enthusiastic
participation of the Irianese, just about wiped out the crocodile population by the time crock killing
was banned in the 1980’s. There are very few big ones left. I saw one which got tangled in a fishing
net, the beast measuring a bit over three meters, with an impressive mouth filled with large enough
teeth to give me the willies and cut way down on my swimming. In 1987 a young woman from
Atuka village was killed by a crocodile, her body cut in half. But in spite of several night-time
crocodile-searching forays, we never saw any critters longer than a half meter.

While pythons are occasionally sighted in the mangroves, including the stunningly beautiful emerald
python, these snakes are not dangerous to humans. Vipers however can and do kill. An elderly lady
headed for the sago groves from Kekwa village was bitten on her ankle and died shortly thereafter.
Moral of the story: wear boots when traipsing around the mangroves.

Rounding out our list of notable reptiles, the mangrove monitor lizard is often hunted by the Kamoro
both for its meat and its skin. The hourglass-shaped drums are topped by a lizard skin playing
surface, fastened to the wooden body by human blood and tied down with long strips of rattan or
some other strong vine. Kamoro legends speak of a huge lizard, now mistakenly called a ‘komodo’ -
these animals are endemic only to Komodo Island and its immediate vicinity, hundreds of kilometers
to the west. Perhaps the origins of these huge lizard myths go back to the Kamoros’ distant ancestors
who may have had uncomfortably close contact with a now extinct Australian lizard, the mother of
monitors, called Varanus prisca, a seven-meter long, one-ton killing machine and Australia’s top
predator. During the Ice Ages, up to 7000 years ago, the shallow Arafura Sea separating Australia
from New Guinea dried up as sea levels dropped up to 50 meters. Although no prisca bones have
been found in Irian, some of the behemoths could have reached what is now the south coast and
made savory if squirming meals out of the Kamoros’ forefathers. But no need to worry about them
when drifting through today’s mangrove swamps. We are assured that they have been extinct for
about 15,000 years.

A most useful family
Two similar species of trees, both of the Rhizophora family, catch attention as they are the most
numerous, species-rich and obvious in the mangroves. Supported by tangles of gracefully arched stilt
roots, these trees line estuaries, the lower reaches of rivers and the mangroves’ meandering
waterways. Long, drooping propagules decorate these evergreens.

The two species are not so easy to tell apart for a casual observer but the Kamoro quickly distinguish
between them. The red mangrove (Rhizophora stylosa) has - often but not always - brown speckles
on its leaves while the tall-stilted mangrove (R. apiculata) lacks these spots and its leaves are more
pointed and slightly longer. Both species are used extensively by the Kamoro who call the red
mangrove ‘pako’ and the tall-stilted mangrove ‘paé’. The natural growth angles of the roots are put
to good use to fashion the adz-like tools they wield to break up the pith of the sago tree, thus
facilitating the separation of the edible starch from the interlaced cellulose fibers. The much-
appreciated high-grade tambelo, the oyster-tasting bivalve, lives in the fallen trunks of both of these

species; the hard trunks are spit with an ax to give easy access to the mollusks. The red mangrove’s
trunk provides a kind of adhesive which, mixed with lime made from burned mollusk shells serves
as a substitute for human blood to fasten the monitor lizard skin playing surface to the drums. A red
color is obtained from soaking the bark. Carvings are then soaked in this dye. The tree’s tanning
properties are put to good use in strengthening fishing nets and new dugout canoes. The fruit is used
as temporary earrings. The Japanese during World War II taught the Kamoro that the part of the tree
holding the fruit can serve as a sugar substitute.

Elsewhere, these two species are heavily exploited for firewood and charcoal and more recently for
plywood, adhesive particle board and wood chips for making cardboard, paper and rayon. Formerly,
these and many other mangrove species were highly valued for their natural tannins, used to cure
leather, to toughen nets and rope for marine use and for fish traps. In some areas of Asia, the bark of
these trees still provides a local remedy for dysentery.

Two other mangrove species, also of the Rhizophora family but of a different genus, occur in the
same vicinity but a few meters back from the waterways. The large-leafed and small-leafed orange
mangrove, Bruguiera gymnorhiza and B. parviflora respectively are called tao and uu in Kamoro.
These trees are one of the largest and most long-lived in the mangrove community. They are
distinguished by their buttress roots at the base of the tree and knee roots pushing up through the soil
from the horizontal root system. The Kamoro use scrapings from the fruit of the tao as a glue and as
a thickening additive to sago gruel or porridge. The circular encapsulating growth holding the seeds
calyx lobes, with numerous even tips are dipped in lime and touched to the face and torso as body
decorations of the initiates in the karapao ritual, making a circle of white dots. The bark of the uu
hold the tambelo brought to the karapao ritual. The uu species mainly cut for house construction,
used in posts, traverse rafters and floor support. For good reason: the wood is highly resistant to
termites and boring toredo worms. The dried out trunks and branches serve as firewood. The color of
the leaves shade towards the yellow-green. In other parts of south-east Asia, the bark of the tao
serves to tan leather and to strengthen fish nets. Its trunk can yield strong, straight planks up to seven
meters long. The wood also yields excellent charcoal. Aside from its use as a condiment and an
adhesive, the bark of this tree serves in many local medicines including for diarrhea, malaria, for
shingles, as eye medicine and generally as an astringent. The roots and leaves are used as treatment
for burns. Trunk sections of tao are also used to attract a tambelo-like mollusk called titiri, found
only in fresh water.

Another member of the Rhizophora family, the genus Ceriops, is known as the yellow mangrove to
Aussies and mbaaka to the Kamoro. While its root system is less conspicuous than that of Bruguiera,
it is also supported by buttress roots and knee or looped surface projections from underground. It is
distinguished by its leaves which, unlike the pointed ones on Bruguiera, are blunt or rounded and
considerably smaller. In Irian, this strong wood was formerly shaped into war-clubs meant on impact
to impart head-spitting aches (splitting head-aches?). The wood from this tree is used to make small
sago beaters, stilt-posts for houses and fences. Outside of Irian, the bark of this genus, especially that
of Cerops decandra, yields a high quality tannin while the sap from the bark provides the dye for
black batiks. The natural tannins from these trees are much cleaner than synthetic ones, with a
minimum of insoluble matter. A decoction from the bark is used in some areas to treat hemorrhages.

Another species, Ceriops tagal, grows the tallest in areas of high seasonal rainfall. Both the sap and
bark provide dyes for batiks, especially the high-quality Javanese sogan-batiks. Combined with other
ingredients, this dye imparts warm, yellowish brown colors which gradually shade into one another
on the cotton cloth. This effect is impossible to achieve with synthetic dyes. When combined with
indigo, the dye yields subtle shades of black and purple. The bark is also used medicinally. The
wood from this tree is used for tool handles as it is resistant to shocks and splitting (see above: good
for splitting heads, but not the wood) and makes a good firewood although the flame may to too hot
for many cooking pots.

A true pioneer
The Avicennia marina is the Aussies’ grey mangrove. The Kamoro call it teako and use it only for
firewood, appreciated for its fast-drying. This is the toughest of mangroves, tolerant of hypersaline
environments, thanks to salt-excreting glands on the leaves. The teko is also the species most widely
distributed in Australia, due to its adaptability to cool temperatures. The cable root system rears up
erect, pencil-sized pneumatophores. The tree grows well in poor soils such as salt flats, colonizing
newly formed mud spreads and sand banks in the tidal zone. It is also a characteristic element of the
outer mangrove fringe along the shore and tidal rivers.

The big apple
The Sonneratia genus of mangroves can be identified by the tall, conical pneumatophores pushing up
thorough the ground from the horizontal roots. Forget about telling the main species apart: even
botanists have a tough time. Unless, that is, you or the botanists are lucky enough to be around for
the one night a year when these trees flower. Then it’s a snap: white flowers grace the Sonneratia
alba while Sonneratia caseolaris sports red ones. The genus is called the apple mangrove due to the
shape of its fruit which the Kamoro children spin like tops. Adults put the tree to use as large house
posts and firewood. These trees are sometimes called firefly mangroves as they serve as social
centers for these insects. In western Indonesia, bats frequently gorge on the copious nectar filling the
calyx cups of the Sonneratia, performing pollination as a side line. In Irian, hawk moths do this job.
The Kamoro call these trees yapako.

The two Lumnitzera species are also tough to tell apart. The Aussies call both of them black
mangroves. The Kamoro refer to them as amau and the wood for house posts, as floor supports to
raise the whole construction above ground and as mooring posts to tied up their canoes. These trees
either have no above ground roots or only small, knee-type ones. The leaves have unique small
indentations at the tips.

The river mangrove, Aegiceras corniculatum, is known to the Kamoro as titipoko. They use the root
for making machete (parang) handles. The tree grows on riverbanks, in thickets up to four meter
high. The flowers are small, white and bunched, smelling sweetly like rotten bananas. The
propagules are short and thin, some five centimeters long. Look for a spiral-patterned cap at the end
of the fruit attached to the tree. These fruits turn from green to red when ripe. These are fashioned
into temporary earrings.

>The cannonball mangrove
The large, melon-sized round fruit of this species makes the common name easy to remember, a lot
simpler than its scientific designation: Xylocarpus granatum. Another common name is monkey-

puzzle, based on the interlocking sections of the fruit. It’s umu to the Kamoro. They use the trunk as
house posts to fashion boards and to make furniture such as chairs and tables, as a substitute for
ironwood. This is their favorite tree for making dugout canoes and paddles. The umu has medicinal
uses as well, its bark used as an astringent. Cannonball mangroves grow to 25 meters, supported by
buttresses at the base and laterally extending plank or ribbon type roots above ground. The leaves,
thickened at the base, allow them to turn to face towards or away from the sun. A closely related
species, the cedar mangrove, Xylocarpus mekongensis, has similar leaves but a smaller fruit and peg
or snorkel-type above-ground spreading roots for pneumatophore-enhanced breathing. The Kamoro
call this species taara and put it to the same use as the umu. Plus using its bark as an additive to palm
wine, sagero. These two species are found in the upper limits of tidal muds in the mangrove swamps.
The umu is associated with nypa palms and Sonneratia species while the taara prefers to hang out in
the Bruguiera gymnorhiza dominated mangrove areas.

The world at large has recognized the high quality, mahogany-like timber of this genus. In one area
of the Kamoro-land, the logging company tried to forbid the locals from cutting these trees, causing
predictable outrage. There is an excellent market for the wood of these trees, with widespread use for
the timber: high quality furniture and cabinet work, carvings, light construction, fence posts, salt-
water pilings, gun stocks, billiard tables and billiard cue butts, tool handles, tobacco pipes.... An oil
extracted from the seeds of the granatum variety is still used for lighting and as hair oil. The burned
seeds of the same species, mixed with sulfur and coconut oil, relieves itchy skin.

Patience: a few more mangroves, landward
The strangely-named looking-glass mangrove, Heritiera littoralis, thrives in the landward side of the
swamps, with substantial fresh water flow. Another common name is milkwood. It is called peyaro
by the Kamoro and they use its trunk for house posts. Relatively easy visual identification is
provided by the silvery undersides of the large, dark-green leaves. The roots system shows above
ground as buttresses at the base of the trunk and spreading plank or ribbon-like extensions. The
seven-centimeter long fruits are highly distinctive, each with a prominent ridge which acts as a keel
or a sail to aid in dispersion once the fruit falls.

Stay away from the sap exuded by the leaves of the aptly named blind-your-eye mangrove,
Excoecaria agallocha to botanists and watakota to the Kamoro. They heat the leaves in the fire and
then apply them to the body to bring down fevers. These tall, up to 30 meter high trees can aggregate
as dense scrub or open woodland or scattered among a lower layer of Hibiscus tiliaceus (see below).
The trees also grow on the landward side to the mangrove area. The density probably depends on the
degree of swampiness and salinity. As fresh water increases, this tree becomes mixed with genera
such as Acacia and Melaleuca, while the ground cover Acrostichum (a type of fern: see below) is
replaced by grasses and sedges. A series of adventitious (not usually occurring) roots sprout from the
bases of both this species as well as Melaleuca, probably in a survival effort in response to
intermittent flooding.

Also towards the drier land, the myrtle mangrove, Osbornia octodonta, becomes peta to the Kamoro.
They say it very closely resembles their amau, the black mangrove (Lumnitzera sp.) and they are
correct. However the peta belongs the Myrtaceae, the same family as the eucalypts, so when the
leaves are crushed, the distinctive smell gives you a positive identification. A red tinge at the base of

the leaves offers the best visual clue. The Kamoro say that this is the second strongest tree in the
mangroves and they use its trunk for house posts and to build piers.

>A herb and a fern
Two low plants, a holly and a fern, are both widespread in the mangrove swamps. The prickly-leafed
holly mangrove, Acanthus ilicifolius, has three important functions for the Kamoro who call it
dowao. Just after birth, the midwife used these thorny leaves to spank the baby in order to make it
cry and start breathing. The stem is thrown to dogs to hunt. And the ash from this plant, mixed with
sago, facilitates catching wild pigs. A brew made from crushed leaves is believed to strengthen the
male sexual organ. This low viny herb grows up to two meters and often become dominant after
mangrove forests have been cleared. It develops adventitious aerial roots which help it to sprawl
over any nearby vegetation. The plant is often seen and easily identified in the muddy soils along
rivers banks.

The mangrove fern, Acrostichum speciosum, is the only fern in which grows on the floor of this
swampy environment: all the other ferns are epiphytic, attached to the trunks and branches of trees.
The Kamoro call this fern titimi and use its stems to make string while the leaves serve to wrap the
tambelo mollusks to keep them fresh during the trip back to the village. A hook made from the stem
helps to pull the tambelo out of its hole. The timimi grows best with freshwater input and it often
dominates in cleared areas. Closer to the coast, the fern grows on slightly elevated sites such as the
tall mounds of the burrowing lobster, Thalassina. The plant is easy to recognize with its long fronds
and small, thin leaves some 15 centimeters long.

The mangrove lily, Crinium pendunculatum, sprouts its leaves directly from its base. Named ape by
the Kamoro, the leaves of this plant serve to wrap tambelo and small mollusks when out in the
mangroves and the mollusks are also cooked in these leaves.

>Camp followers: mangrove associates
A fair number of tree species live at the fringes of the mangroves, in areas where fresh water cuts
down on salinity, thus reducing or eliminating the need for salt water adaptations.

The Barringtonia formation, the name emphasizing the dominant genus, contains a group of different
trees growing together along rivers and on the landward side of the tidal swamps. Several species of
Barringtonia yield saponins from their crushed bark and leaves, locally used as fish poison. Washed
into stretches of still or slow moving waters, the saponin stuns the fish which then float to the
surface, paralyzed but very edible. The most common tree of this type, Barringtonia racemosa, rears
up so frequently in the milieu that its’ common English name is the freshwater mangrove - although
it does not really qualify for mangrove status, lacking a halophytic strategy. Nor can it qualify by its
roots as it has none above ground level. (Note: not all trees with above-ground roots are necessarily
mangroves and not all mangroves have above-ground roots, although the majority do so.) The tree
sometimes forms pure stands along tidal rivers or in the upper mangrove swamps. It is also found in
the company of beach dwellers who have sneaked inland, the casuarina and the hibiscus, along with
pandans. Identification of this Barringtonia is relatively easy: the leaves are large, up to 40 cm. long
and 15 cm. wide, with pointed tips, slightly toothed edges along with the giveaway, very pronounced
veins. The Kamoro call this tree uni and use it as a fish poison as well as to toll up the tambelo to

carry home. Elsewhere, the wood is used for temporary construction, local house building and the
tree is planted as an ornamental. Medicinal uses are varied, changing according to locality.

Aside from the familiar coconut trees, the casuarinas are the easiest to recognize along the beach
front and continuing a fair ways inland, but only in relatively dry areas, sometimes associated with
the Barringtonia formation. Looking like pine trees on vacation on a tropical beach, it is the most
wide-spread and obvious along the Kamoro seashore, occurring naturally at the inland fringe of the
beach where they intermingle with patches of planted coconuts. A bit further to the east, a long
section of similar Asmat sea front has been named the Casuarina Coast.

The casuarina tree, also called the coast she-oak or whistling pine, appears closely related to pines
due to its soft, thin, needle-like leaves. But appearances are deceiving as this tree has a family of its
own, named logically enough Casuarinacea. It occurs naturally from south Asia all the way to
Polynesia. The tree is also planted for erosion control and land reclamation, especially in the
typhoon zone, due to its resistance to high winds. A 3000-km. long belt of casuarinas line the
southern Chinese coast.

Mankind has found many uses for this omnipresent tree. It is cut for firewood and produces excellent
charcoal. The bark, which contains tannins, strengthens fishing nets, dyes fabrics a muted red color
and was formerly used to preserve leather. The bark is also used in local medicines for dysentery,
diarrhea and just plain stomach aches. The powdered bark helps to heal shameful facial pimples and
a decoction made from the twigs brings down swellings. Casuarina poles maintain their age-old
popularity for fishing boat masts, oars, tool handles, salt and fresh water pilings and fish traps.
Modern uses include telegraph poles, mine props, raw material for paper, pulp, chipboard and rayon
fibers. In traditional underground ovens, the needle-like leaves function in heat retention in the pre-
fired stones which cook the food by contact.

Iiri is the Kamoro name for the casuarina. Today it is occasionally used for firewood but in former
times the tree held a ritual significance. The ‘owner’ (tuan pesta) of the kawaré ritual cut down one
of these trees which then served as the host for an ancestral spirit who would be invited to the
following ceremonial activities. Under pressure from church and state, this ritual declined slowly
and was finally abandoned in the early 1950’s but it saw a recent revival at Ipaya village to answer a
request of some foreign visitors.

Two other members of the Barringtonia bunch also belong to the 200-species-strong hibiscus-related
plants. Both are found just off the beach as well as inland, near fresh water. Identification is easy
thanks to the typical large and showy flowers. The Hibiscus tiliaceous tree, called native hibiscus or,
less often, cottonwood, shows heart-shaped leaves and five-petaled flowers. The very similar
Thespecia populnea, the Pacific rosewood, can be distinguished by its similarly shaped but more
elongated leaves and five dark spots at the center of the flower.

Both of these species, respectively called iwae and manare by the Kamoro, have the same multi-
purpose. The inner bark, fashioned into and excellent string. This is then turned into strong carrying
bags, fishing nets and, formerly, items of clothing. The string is also wound around machete
(parang) handles for a better grip and used to tie the monitor lizard skins on top of wooden drums.
The tree’s sap and leaves, boiled with water and drunk by pregnant women, insures a smooth birth.

The crushed tips of the leaves absorb poison from catfish spines and stingray tails but the concoction
does not work for snake bites. Recently, the Kamoro have found that they can chew the leaf tips (as
a substitute for siri) with the betel nut to produce mild euphoria.

Elsewhere, these two trees have similar uses: light construction, including simple houses, interior
trim, implements, tool handles and musical instruments. The bark is made into good quality, salt-
resistant rope, also used for caulking boats. It local medicine however, the two species have different
applications. The bark and leaves of the native hibiscus relieve coughs, sore throats and tuberculosis.
The Pacific rosewood’s core functions against colic and fever. The leaves and fruit are applied to
cure skin diseases while the ripe fruit, crushed and mixed with coconut oil, gets rid of lice. The wood
and yellow gum provide a dye while the young leaves are eaten as a vegetable. Both species are
grown near temples in many areas of the Pacific and elsewhere planted as roadside ornamentals.

>The nypa palm: untapped potential
Very obvious monospecific stands of nypa crowd together on the riverbanks of the mangrove
swamps where salinity levels are lower than near the sea. This unusual palm has no stem as the long
fronds shoot up directly from the base of the plant. A unique inflorescence arises among the
leaves and bears unisexual flowers of both sexes. Its eye-catching, spiky fruit comes in soccer-
ball size. If your canoe zips along at the right time of the year, the reward is seeing a very pretty and
orderly series of yellow flowers carefully displayed on a clump arising from the plant’s base. A less
appealing spectacle, the normally buried underground axis looks just like overlapping cow plats.

This plant, one of the 3000 different palms, is among the most ancient in existence. Its pollen is one
of the oldest of the angiosperms, traceable to a modern species and recorded from the Upper
Cretaceous sediments. The mangrove palm is isolated within the palm family, an advanced member
which has pursued an independent line of specialization, adapting to a partially saline environment.
Somewhere back in its evolutionary history, the nypa palm has a possible relation with the pandanus

Elsewhere in south-east Asia, the nypa palm is treated to yield molasses, sugar, vinegar and alcohol.
And the production can be excellent: up to 11,000 liters of alcohol per hectare, although this requires
high labor input. The nypa’s inflorescences are tapped, producing a sap which quickly and
spontaneously ferments. Et voilà: in 30 hours we have a toddy whose alcohol content varies from six
to nine per cent. This toddy can then be distilled into a more potent brew. In some areas outside of
Irian, traditional medicine uses the juice of the young shoots against herpes and the ash of the plant
to treat headaches and toothaches.

To the Kamoro, this palm serves many purposes. But only in the westernmost village, Potowai Buru,
is there an alcoholic beverage, called bobo, made from the nypa. Called awani by the Kamoro, its
fronds are widely used for thatching, although not as good as sago palm thatch. A mat (tikar) made
of the interwoven leaves of the awani serve as both inner and outer house walls. This mat, called ao
in Kamoro, can be also used as a sleeping mat to help heal the sick. The leaves, called kipere, are
also woven into temporary baskets used to bring fish, sago grubs, crabs or mollusks back to the
village. The burned tips of the frond ribs are stuck into the wounds made by the stingray in order to
counteract the poison. The burned ribs in a decoction prevent fever. The fronds are used to relieve
aching bones. The young, unopened shoots make a good wrapper for tobacco for home-made

cigarettes. Short pins are fashioned from the leaf ribs to pin together the leaves used for thatching.
The meat of fruit, called keta, is sometimes eaten when it ripens, around June to September. During
the karapao ritual, huge rectangles of sago are wrapped in the leaves of the awani. A separate
package is made the same way to hold a sago and mollusk mixture.

REDO THIS LAST PORTION!!! (4. Text mangroves)

The Kamoro distinguish between three different species of pandanus for which we have been unable
to find the scientific names. The most important is a kind they call mani, which bears a large, red
fruit. This is eaten with sago and much appreciated for its oily quality. Another kind, called katang,
is used as tongues to pull things out of fires after they have been cooked. The yapinako kind of
pandanus has wide leaves which are plaited to form temporary shelters.


To top