The morning was still too dark to know that it looked charcoal with a
white ruff. We have seen it twice before, but always too far away to
identify.
Today I learned of an Australalian bird similar to the ostrich.The
name of this bird is the cassowary. The two excertps are from
Wikipedia:
"The cassowaries are ratites, very large flightless birds, in the
genus Casuarius native to the tropical forests of New Guinea,
nearby islands and north-eastern Australia.[2] There are three
extant species recognized today. The most common of these,
the Southern Cassowary, is the third tallest and second heaviest
living bird, smaller only than the ostrich and emu.
Cassowaries feed mainly on fruit, although all species are truly
omnivorous and will take a range of other plant food including
shoots, grass seeds, and fungi in addition to invertebrates and
small vertebrates. Cassowaries are very shy, but when
disturbed, they are capable of inflicting serious or even fatal
injuries to dogs and people."
"The Northern and Dwarf Cassowaries are not well known.
All cassowaries are usually shy birds of the deep forest,
adept at disappearing long before a human knows they are
there. Even the more accessible Southern Cassowary of the
far north Queensland rain forests is not well understood.
Females are bigger and more brightly colored. Adult Southern
Cassowaries are 1.5 to 1.8 metres (4.9–5.9 ft) tall, although
some females may reach 2 metres (6.6 ft),[5] and weigh 58.5
kilograms (129 lb).[6]
All cassowaries have feathers that consist of a shaft and loose
barbules. They do not have retrices (tail feathers) or a
preen gland. Cassowaries have small wings with 5-6 large
remeges. These are reduced to stiff, keratinous quills, like
porcupine quills, with no barbs.[6] A claw is on each second
finger.[7] The furcula and coracoid are degenerate, and their
palatal bones and sphenoid bones touch each other.[8] These,
along with their wedge-shaped body, are thought to be
adaptations to ward off vines, thorns and saw-edged leaves,
allowing them to run quickly through the rainforest.[9]
A cassowary's three-toed feet have sharp claws. The second toe,
the inner one in the medial position, sports a dagger-like claw
that is 125 millimetres (5 in) long.[6] This claw is particularly
fearsome since cassowaries sometimes kick humans and animals
with their enormously powerful legs (see Cassowary Attacks, below).
Cassowaries can run up to 50 km/h (31 mph) through the dense
forest. They can jump up to 1.5 metres (4.9 ft) and they are good
swimmers, crossing wide rivers and swimming in the sea as well.[7]
called casques on their heads, up to 18 cm (7 in).[8] These
consist of "a keratinous skin over a core of firm, cellular
foam-like material".[10] Several purposes for the casques have
been proposed. One possibility is that they are secondary
sexual characteristics. Other suggestions include that they are
used to batter through underbrush, as a weapon for dominance
disputes, or as a tool for pushing aside leaf litter during foraging.
The latter three are disputed by biologist Andrew Mack,
whose personal observation suggests that the casque amplifies
deep sounds.[11] However, the earlier article by Crome and
Moore says that the birds do lower their heads when they are
running "full tilt through the vegetation, brushing saplings aside
and occasionally careening into small trees. The casque would
help protect the skull from such collisions."[10] From an
engineering perspective the wedge shaped casque is also the
most efficient way to protect the head by deflecting falling fruit.
As cassowaries live on fallen fruit they spend a lot of time under
trees where seeds the size of golfballs or larger are dropping
from heights of up to 30 metres. Mack and Jones also speculate
that the casques play a role in either sound reception or acoustic
communication. This is related to their discovery that at least the
Dwarf Cassowary and Southern Cassowary produce very-low
frequency sounds, which may aid in communication in dense
rainforest.[11] This "boom" is the lowest known bird call, and
is on the edge of human hearing.[12] Crowe described a
cooling function for the very similar casques of guineafowl.
The average lifespan of wild cassowaries is believed to be
about 40 to 50 years.[13]
Distribution and habitat
Cassowaries are native to the humid rainforests of New Guineaand nearby smaller islands, and northeastern Australia.[2] They
will, however, venture out into palm scrub, grassland, savanna,
and swamp forest.[8] It is unclear if some islands' populations are
natural or the result of trade in young birds by natives. The
cassowary is usually found in a rainforest of a sort but in Australia
mostly Northern Queensland in places as in Cairns or The Great
Daintree Rainforest.
Behaviour and ecology
Cassowaries are solitary birds except during courtship, egg-laying,and sometimes around ample food supplies.[8] The male cassowary
defends a territory of about 7 square kilometres (1,700 acres)
for itself and its mate, while females have overlapping territories
of several males.[13] While females move between satellite
territories of different males, they appear to remain within the
same territories for most of their lives, mating with the same or
closely related males over the course of their life span. Courtship
and pair bonding rituals begin with the vibratory sounds broadcast
by females. Males approach and run with necks parallel to the
ground with dramatic movements of the head, which accentuate
the frontal neck region. The female approaches drumming slowly.
The male will crouch upon the ground and the female will either
step on the males back for a moment before crouching beside
him in preparation for copulation or she may attack. This is often
the case with the females pursuing the males in ritualistic chasing
behaviors that generally culminate in water. The male cassowary
dives into water and submerges himself up to his upper neck and
head. The female pursues him into the water where he eventually
drives her to the shallows where she crouches making ritualistic
motions of her head. The two may remain in copulation for extended
periods of time. In some cases another male may approach and run
the other male off. He will climb on to her to copulate as well. Males
are far more tolerant of one another than females, which do not
tolerate the presence of other females.
Reproductive
The breeding season starts in May or June. Females lay three toeight large, dark bright green or pale green-blue eggs in each
clutch into a prepared heap of leaf litter.[8] These eggs measure
about 9 by 14 centimetres (3.5 by 5.5 in) — only Ostrich and
Emu eggs are larger. The female does not care for the eggs or
the chicks but moves on to lay eggs in the nests of several other
males. The male incubates the eggs for 50–52 days, removing or
adding litter to regulate the temperature, then protects the
brown-striped chicks, who stay in the nest for about nine months,
defending them fiercely against all potential predators, including
humans. The young males then go off to find a territory of their own.[8][13]
-
- "Young cassowaries are brown and have buffy stripes.
- They are often kept as pets in native villages
- [in New Guinea], where they are permitted to roam like
- barnyard fowl. Often they are kept until they become
- nearly grown and someone gets hurt. Mature cassowaries
- are placed beside native houses in cribs hardly larger than
- the birds themselves. Garbage and other vegetable food is
- fed them, and they live for years in such enclosures; for in
- some areas their plumage is still as valuable as shell money.
- Caged birds are regularly bereft of their fresh plumes."[9]
Diet
Cassowaries are predominantly frugivorous. Besides fruits, theirdiet includes flowers, fungi, snails, insects, frogs, birds, fish, rats,
mice, and carrion. Fruit from at least twenty-six plant families
have been documented in the diet of cassowaries. Fruits from
the laurel, podocarp, palm, wild grape, nightshade, and myrtle
families are important items in the diet.[8]
The cassowary plum takes its name from the bird. Where trees
are dropping fruit, cassowaries will come in and feed, with each
bird defending a tree from others for a few days. They move on
when the fruit is depleted. Fruit is swallowed whole, even items
as large as bananas and apples.
Cassowaries are a keystone species of rain forests because
they eat fallen fruit whole and distribute seeds across the jungle
floor via excrement.[8]As for eating the Cassowary, it is supposed
to be quite tough. Australian administrative officers stationed in
New Guinea were advised that it "should be cooked with a stone
in the pot: when the stone is ready to eat so is the Cassowary".[14]
Role in seed dispersal and germination
and usually pass viable seeds in large dense scats. They are known
to disperse seeds over distances greater than a kilometre, and thus
play an important role in the ecosystem. Germination rates for
seeds of the rare Australian rainforest tree Ryparosa were found
to be much higher after passing through a cassowary's gut (92% versus 4%).[15]
Status and conservation
Kofron and Chapman (2006) assessed the decline of this species.
They found that, of the former cassowary habitat, only 20 -
25% remains. They stated that habitat loss and fragmentation is the
primary cause of decline.[16] They then studied 140 cases of
cassowary mortality and found that motor vehicle strikes accounted
for 55% of them, and dog attacks produced another 18%. Remaining
causes of death included hunting (5 cases), entanglement in wire (1 case),
the removal of cassowaries that attacked humans (4 cases), and
natural causes (18 cases), including tuberculosis (4 cases). 14 cases
were for unknown reasons.[16]
Hand feeding of cassowaries poses a big threat to their survival, because
it lures them into suburban areas. There, the birds are more susceptible
to vehicles and dogs.[17] Contact with humans encourages cassowaries
to take food from picnic tables.
Feral pigs are a huge problem. They destroy nests and eggs but their
worst effect is as competitors for food, which could be catastrophic
for the cassowaries during lean times.
In February 2011 Cyclone Yasi destroyed a large area of cassowary
habitat, endangering 200 of the birds, around 10% of the total Australian
population.[18]
Relationship with humans
Cassowary attacks
Cassowaries have a reputation for being dangerous to people anddomestic animals. During World War II American and Australian
troops stationed in New Guinea were warned to steer clear of
them. In his book "Living Birds of the World" from 1958,
ornithologist Thomas E. Gilliard wrote:
- "The inner or second of the three toes is fitted with a long,
- straight, murderous nail which can sever an arm or
- eviscerate an abdomen with ease. There are many records
- of natives being killed by this bird."[19]
in print by authors including Gregory S. Paul (1988)[20] and
Jared Diamond (1997).[21] Of 221 attacks studied in 2003, 150 were
against humans. 75% of these were from cassowaries that had been
fed by people. 71% of the time the bird chased or charged the victim.
15% of the time they kicked. Of the attacks, 73% involved the birds
expecting or snatching food, 5% involved defending natural food
sources, 15% involved defending themselves from attack, 7% involved
defending their chicks or eggs. The 150 attacks included at least one
human death.[22]
One documented human death was caused by a cassowary on 6 April 1926.
16-year old Phillip McClean and his brother, aged 13, came across a
cassowary on their property and decided to try to kill it by striking it with clubs.
The bird kicked the younger boy, who fell and ran away as his older brother
struck the bird. The cassowary then charged and knocked the older
McClean to the ground and kicked him in the neck, opening a 1.25 cm (0.49 in)
wound which may have severed his carotid artery. The boy managed to escape,
but died shortly afterwards as a result of his injuries.[23
]Cassowary strikes to the abdomen are among the rarest of all, but there
is one case of a dog that was kicked in the belly in 1995. The blow left
no puncture, but there was severe bruising. The dog later died from an
.jpg)
Now the more humorous side of cassowary. Go to Facebook--
where Kenny Cassowary has a face book site, I was told, but
couldn't locate, I did find Cassowary! on FB--with some
exceptional pictures! Kenny Cassowary is living at the beach
and stealing food from tourists, no aggressive behavior at all,
but he may not be breeding age yet. Currently he is like the
lovable but exasperating Yogi Bear of Jellystone Park!
Back to my birds--we had the feeder that is attached to the window
removed so as to clean it and replace the food with the sunflower,
peanuts, dried cherry and raisin blend. While the feeder was feeder
was down, here comes flying my favorite (very blond--not in color though)
tufted titmouse. He couldn't stop, looked very suprised and grabbed hold
of the attachment to regain his balance and gave me suprised look
before flying away.
All for today.
kate thorn
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