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| Royal penguins, Macquarie Island - Image Author: M. Murphy - Public Domain |
The Royal penguin (Eudyptes schlegeli) breeds on Macquarie Island and the Bishop and Clerk Islands, roughly equidistance between Antarctica, Australia and New Zealand. They form very large, crowded colonies on slopes covered by rough tufts of grass and loose stones. The largest colony is on Macquarie Island at Hurd Point with an estimated population of 500,000 pairs out of a total world population of 850,000 pairs in 1984-85. There are estimated to be 1,000 pairs on the Bishop and Clerk Islets. They were once regarded as a subspecies of the Macaroni penguin but today many scientists consider them a separate species in their own right. They are related to the Macaronis and their breeding territories often overlap. Like the Macaroni penguin, Royals are members of the crested penguins, or genus Eudyptes. Other members of this group are Fiordland, Snares, Erect-crested, and Rockhopper penguins.
Description
Royals do look similar to Macaroni penguins but are a little smaller. The faces of Macaroni penguins are mostly black while Macaronis have mainly white faces with white chins. Royal penguins can grow to about 28 inches tall and weigh up to 13 pounds. They are not as large as Yellow-eyed, King or Emperor penguins but considerably larger than Little Blue penguins.
Hunting and Diet
The Royal penguin’s diet consists mainly of krill, squid and
fish caught using pursuit diving at depths of between 50-150 feet. Their dives
will not usually last longer than 2 minutes. They are strong, fast swimmers and
their webbed feet and flippers power them through the water at up to 20 miles
per hour.
Breeding
The Royals breed in a synchronized cycle beginning when the
males arrive on Macquarie
Island to claim nesting
sites in late September. The females arrive later in October.
Nests are often scratched out hollows lined with pebble or
vegetation in the scree and grass tufts on slopes by the shore where the female
lays 2 eggs. Typically with the crested penguin group the first egg will be
neglected and not hatch. It usually takes around 30 days to hatch the second
egg.
For the next 3 to 4 weeks it is the task of the male to
guard the chick until it has grown big enough to form nursery groups with other
chicks. These then huddle together for warmth and security while both parents
hunt at sea. About late February the chicks fledge, loosing their down and
growing adult plumage. They are then ready to hunt in the sea on their own. Around May after the adults have moulted they will leave Macquarie Island
for the open sea roaming the southern ocean between Tasmania
and Antarctica until the next breeding cycle.
Threats and Predators
For many years Royal penguins were hunted by humans for
their oil but now they are protected. Nevertheless they still suffer from human
activity such as over fishing and oil spills. In the sea they are prey to sharks and seals while on land
skuas steal eggs and kill chicks. Human introduced species have caused havoc on
Macquarie Island which was not helped by further
human interference. On Macquarie
Island cats had
previously kept the rabbit and rodent population under control though they also
preyed on penguins. When cats were removed from the island the population of
rabbits multiplied causing so much damage to plant life it could be seen from
space. Now the Australian government plans to remove rats, mice, and rabbits
from the island. The International Union for Conservation of Nature have
listed Royals as Vulnerable
(VU D2) on the IUCN Red List of Threatened Species and regarded as having a
high risk of extinction in the wild.
References, Attributions and Further Reading
Royal Penguin from Wikipedia
As an animal-lover, I wonder if the cats were a species original to the island or if they were also a kind of invasive species (no offense to cats, but they do kill a lot of birds, etc.). That's fascinating how the damage by rabbits once they took the cats away could be seen from outside the Earth. I didn't know much about rabbits in Australia until I saw the excellent movie "Rabbit-Proof Fence" several years ago, even though it was not focused on wildlife per se but on human interactions, specifically mistreatment of indigenous people.
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