www.penguin.net.nz
enlarged
from above picture - note the yellow eye.
The Yellow-eyed Penguin, Megadyptes antipodes,
or Hoiho is a penguin native to New Zealand.
Previously thought closely related to the Little
Penguin, Eudyptula minor, molecular research has shown
it more closely related
to penguins of the genus Eudyptes. Like most other penguins, it is
mainly piscivorous.
The species breeds around the South Island of New Zealand, as well
as Stewart, Auckland and Campbell Islands.
This is a fairly large penguin, averaging 75 cm (30 in) long and
weighing about 6.3 kg (14 lbs). Weights vary through the year
being greatest, 7 to 8 kg (15.518 lbs), just before moulting
and least, 5 to 6 kg (1113.2 lbs), after moulting.
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It has a pale yellow head and paler yellow iris with black feather
shafts. The chin and throat are brownish-black.
There is a band of bright yellow running from its eyes around the
back of the head.
The juvenile has a grayer head with no band and their eyes have
a gray iris.
The Yellow-eyed Penguin may be long lived, with some individuals
reaching 20 years of age.
Males are generally longer lived than females, leading to a sex
ratio of 2:1 around the age of 1012 years.
Lupin,
Lupinus arboreus,
© http://www.flora.org.gg/
This penguin usually nests in forest or scrub, among Native Flax
(Phormium tenax) and lupin (Lupinus arboreus),
on slopes or gullies, or the shore itself, facing the sea. These
areas are generally sited in small bays or on headland areas
of larger bays. It is found in New Zealand, on the south-east coast
of South Island, Foveaux Strait and Stewart Island/Rakiura,
and Auckland and Campbell Islands. It expanded its range from the
subantarctic islands to the main islands of New Zealand
after the extinction of the Waitaha Penguin several hundred years
ago.
Three
Yellow-eyed Penguins at the edge of the sea
© www.photovolcanica.com
The current status of this penguin is endangered, with an estimated
population of 4000. It is considered one of the world's rarest
penguin species. The main threats include habitat degradation and
introduced predators.
In spring 2004, a previously undescribed disease killed off 60%
of Yellow-eyed Penguin chicks on the Otago peninsula and
in North Otago. The disease has been linked to an infection of Corynebacterium,
a genus of bacteria that also causes
diphtheria in humans. It has recently been described as diphtheritic
stomatitis. However, it seems as if this is just a secondary
infection. The primary pathogen remains unknown. A similar problem
has affected the Stewart Island population.
The Yellow-eyed Penguin generally forages 713 km (48
miles) offshore, and travelling on average around 17 km (11 miles)
away from the nesting site. Birds leave the colony at dawn and return
the same evening during chick rearing, although may
spend 23 days at sea at other times. Average depth dived is
34 m (112 ft).
Pair
of unhatched, abandoned eggs in nest bowl.
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The Yellow-eyed Penguin pursues prey in 2060 m (66196
ft) deep dives. Around 90% of the Yellow-eyed Penguin's diet
is made up of fish; with cephalopods such as the arrow squid, Nototodarus
sloanii, making up the remainder.
Fish species consumed include the blue cod, Parapercis colias,
red cod, Pseudophycis bachus, opalfish, Hemerocoetes monopterygius,
and New Zealand Blueback Sprat, Sprattus antipodum, all between
2 and 32 cm (113 in) long.
Cephalopods make up almost half (49%) of the diet of immature birds.
Whether or not Yellow-eyed Penguins are colonial nesters has been
an ongoing issue with penguin people in New Zealand.
Most Antarctic penguin species nest in large high density aggregations
of birds. In contrast yellow-eyed penguins do not nest
within visual sight of each other. While they can be seen coming
ashore in groups of 46 or more individuals then disperse
along track to individual nests sites out of sight of each other.
The consensus view of New Zealand penguin workers is that it is
preferable to use habitat rather than colony to refer to areas where
yellow-eyed penguins nest.
Natural
nest site, Otago Peninsula, YEPT Reserve
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Several mainland habitats have hides and are relatively easily accessible
for those wishing to watch the birds come ashore.
These include beaches at Oamaru, Moeraki light-house, a number of
beaches near Dunedin, and The Catlins.
In addition commercial tourist operations on Otago Peninsula also
provide hides to view Yellow-eyed Penguins.
A reserve protecting more than 10% of the mainland population was
established at Long Point in the Catlins in November
2007 by the Department of Conservation and the Yellow-eyed Penguin
Trust.
Allopreening penguin
pair
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