Fast Fact Attack: Endangered Species No. 101 – The Yellow-eyed Penguin


Yellow-eyed penguin

“Wilderness is not a luxury but a necessity of the human spirit, as vital to our lives as water and good bread”
Edward Abbey

Yellow-eyed penguin courtship This Antipodean yellow-eyed penguin may well be the rarest penguin on earth, and if conservation efforts fail, it could be lost altogether.  The arrival of man in the New World has done untold damage to the species.  Its coastal habitat has been given over to development and agriculture.  Along with the loss of habitat, sheep and cattle not only graze the land, they are also capable of treading on nests, destroying eggs and often killing young chicks.  A further introduction of cats, dogs, rats and ferrets has seen adults penguins killed, eggs stolen and chicks eaten.

Rats were the first introduced predators. Although this was not deliberate, you can imagine the rate at which they multiplied.  Cats were then needed to control the rats.  In they came.  Most of these became feral.  Ferrets and other mustelids were brought in during the 1880s to control the burgeoning rabbit population (yet another unwise introduction to the islands).

Adult birds can escape the smaller predators, but they cannot escape from, nor defend themselves against the dogs.  They are particularly vulnerable during the moulting Yellow-eyed penguin (Megadyptes antipodes) at Bushy Beach, Oamaru, New Zealand. moulting,season when they cannot run to the sea and immerse themselves.  Needless to say, chicks and juveniles do not stand a chance against any of these predators. There is also a high recorded rate of chick mortality through starvation and disease.

Then, there are the commercial fishing practices.  Every year, yellow-eyed penguins die from entanglement in fishing nets.  According to the Yellow-eyed Penguin Trust, numbers of by-catch of yellow-eyed penguins by commercial fisheries may be considerable. 

The Trust, which relies upon donations and volunteers, has instigated various measures to try and ensure the continuation of the species.  It is doubtful the colonies could survive without the ongoing predator control and maintenance which is now in action.  The Department of Conservation is also strongly involved in monitoring and maintaining breeding sites over the yellow-eyed penguin’s range, and the local community is actively involved in conservation plans.  Fishing practices are being addressed.

This is the good news.  The bad news is, no-one has any control over the unexplained outbreaks of disease which have occurred over the past three decades.  The causes of these catastrophic events still remain a mystery.

Yellow eyed penguin coupleAdult yellow-eyed penguins have bluish-grey backs and flippers, with a white underside and pink feet.  In the water, this combination of light and dark colouring (known as counter-shading) provides camouflage from both above and below.  A diving penguin becomes totally dark when seen from above and totally light when seen from below.

A distinctive yellow eye and a bright yellow stripe, which runs from the eyes to the back of the head, sets them apart from other species of penguin.  Under water, all penguins have optimum vision and are able to spot prey in the murkiest of waters.  Their eyesight is said to be better in the water than on land.

The average adult yellow-eyed penguin can reach a height of two feet and weigh around thirteen pounds.  Males tend to be slightly taller and heavier than females.

These penguins make a lot of noise when calling to each other.  This unique call prompted the Māori name, Hoiho, meaning ‘noise shouter’.   The call is used as a general form of communication within the colonies.

Yellow eyed penguin 'porpoising'Penguins are very accomplished swimmers and spend up to seventy-five per cent of their lives at sea. Having lost the ability to fly millions of years ago, they now have well-developed, powerful flippers and streamlined bodies.  They can achieve speeds of up to twenty miles per hour in the water, where they practice ‘porpoising’;  the art of leaping in low arcs in and out of the water.  This reduces friction by coating the feathers with tiny bubbles, and, at the same time, the movement allows them to breathe more evenly.  It is thought the penguins porpoise as a means of evading predators, though some say it is simply out of pure joy.   I would prefer to believe the latter.  There is no doubt they are joy to behold to the onlooker. 

Primarily a benthic forager, the yellow-eyed penguin is known to dive up to depths of five hundred feet and travel along the bottom for up to one hundred and sixty feet. Maximum dive time is thought to be three and a half minutes.

Yellow eyed penguin chick by Darren Scott free download from flickrThe breeding season begins in mid-August.  Penguins are ready to breed when they are three or four years old, at which time life-long relationships are formed.  Nest sites are chosen together and normally two eggs will be laid in September.   For the next forty-three days, both parents will share the incubation.   After hatching, one parent will guard the chicks while the other is at sea foraging.  The forager will return daily to feed the chicks and relieve the partner.  Chicks are fed by regurgitating stomach contents.  When the chicks are about six weeks of age, both parents go to sea to gather food for their rapidly growing young.

Chicks are covered in thick, brown, fluffy feathers when first hatched.  They shed these and develop their adult plumage when they fledge in February, and off they go to sea.  This can be an extremely hazardous time with less than twenty per cent of juveniles returning and reaching maturity.  The ones that do survive may live for up to twenty-four years.

Seventeen species of penguin exist in the world, of which seventy-five per cent  suffer from declining populations.   Only five of the species are not considered vulnerable, threatened or endangered.  The endangered yellow-eyed penguins tend to return to the small colonies where they were born; consistently low survival rates from any given colony could eventually end in its extinction.

Natural Habitat
Both marine and land habitat are important to the yellow-eyed penguin, and it depends heavily on each of them.  Crucial land habitat includes forest , scrubland and pasture. These spaces are used for resting and building nests.  Their indispensable marine habitat provides food and a means of travel between locations.
Where
New Zealand – South Island, Stewart Island and the sub-Antarctic islands of  Auckland and Campbell.  
What they eat
Arrow squid forms the most part of the diet, followed by such as blue cod, red cod, opal fish and  blueback sprat.
Threats
Coastal habitat destruction and habitat loss due to human activities.  Introduction of domestic mammalian predators such as cats, dogs, rats and ferrets.  By-catch by commercial fisheries.  Outbreaks of disease.  Natural predators include sharks, barracouta, Hooker’s sea lions, skua and giant petrel.
Status: Endangered
The yellow-eyed penguin (Megadyptes antipodes) is listed on the  IUCN Red List of Threatened Species  as Endangered.  The species is also listed by the New Zealand Department of Conservation as being Threatened.  In 2010 the yellow-eyed penguin was granted protection under the United States Endangered Species Act.
It is fully protected by law under New Zealand’s Wildlife Act 1953.
The Yellow-eyed Penguin Trust is engaged with the MPI and the fishing industry to attempt to resolve the threat of by-catch.  Predator control programmes are in place, barriers have been created preventing humans from disturbing nests and a habitat restoration plan is in action.
Six hundred to eight hundred breeding pairs are thought to inhabit the New Zealand mainland, including Stewart Island.  There are no captive populations of yellow-eyed penguins. 

Related Articles
Yellow-eyed penguin nest numbers down (October 2013)
Penguin deaths ‘devastating’  (February 2013)
Tagging yellow-eyed penguins on the Otago Peninsula (February 2013)
Climate change is killing baby penguins
The Galapagos Penguin


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9 thoughts on “Fast Fact Attack: Endangered Species No. 101 – The Yellow-eyed Penguin

  1. What cute guys these are!!! And ya know that’s the part that’s so hard to wrap my mind around. How does anyone look at a creature like that and want to do it harm??? Did someone cut out their hearts at birth?! Blessings, Natalie

    • Isn’t it a shame, Natalie! Adorable little things…and yet again, stupidity (note the word!) came into play at one stage. And, that awful industrial fishing that we see everywhere is a big problem. But, thankfully, the residents are trying their very best to put it all right 🙂

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