Status (IUCN v3.1)
This species tends to live in very small colonies and has many predators, making it a preservation concern. Listing should remain “vulnerable,” because some large colonies do exist, on different islands of New Zealand that are relatively free of predators, so that if one of these colonies should be destroyed enough penguins will remain to repopulate. Species has land/water protection and management, site/area protection and management, and invasive/problematic species control.
Increases in human populations near penguin colonies would lead to the presence of more dogs and cats, and therefore more predation on colonies. Protection of Weka populations (listed as vulnerable by the IUCN) will possibly result in larger Weka populations and therefore more penguin egg/chick kills. Destruction of Weka plant foods would lead to more predation on birds.
Increasing tourist interest in penguins will disturb the colonies that are easily accessible, possibly leading to the failure of these colonies, as well as leading to more traffic and therefore more accidental kills by vehicles. Squid fisheries can reduce the food available to the penguins, as well as increase the possibility of their entanglement and death in trawling nets. Habitat modification, such as the loss of small streams (excellent nesting sites) will also result in fewer penguins.
Marine perturbations can cause changes in the amount of prey available to the birds, and a rise in sea temperature would have the same effect (BirdLife 2009).
The most important threats are Weka predation and human disturbances. Until more protection is established, human threats will continue and possibly rise, while Weka predation will probably remain constant.
Adult: Adult plumage is similar in males and females, with blue-black body, flippers, and tail, white stomach, and black head with conspicuous yellow stripe of plumage starting a bare patch of skin at the base of a reddish-brown bill and extending back, white patches on cheeks.
Juvenile: Juveniles are similar to adults but smaller, with a blacker bill and no bare patch of skin at base, shorter yellow plumes along sides of head; white parts are grayer in juveniles than in adults.
Chick: Down feathers are gray, and thicken after hatching.
Males are usually larger with larger bills; the ratio of bill depth for females to males is approximately .83
Weight: 3 kg
Height: 60.0 cm
Beak: 5.1 cm
Flipper: 18.5 cm
Foot: 12.5 cm
Weight: 2.91 kg
Height: 60.0 cm
Beak: 4.5 cm
Flipper: 17.7 cm
Foot: 11.3 cm
There are six calls: (1) The “contact call” is a simple cry used at sea, (2) the “mutual display call” is 4-5 second sexual call consisting of throbs increasing in length, (3) the “trumpeting call” is another sexual call very similar to the mutual display call but beginning with a grunt, (4) the “hiss” is a low-pitched sound ending with a growl, used during fighting, (5) the “bill-locking call” is used in direct fighting and consists of a single throb, and (6) the “squeal” is emitted in response to danger. Chicks simply “cheep.”
Average Arrival Date: July 12
Average Egg Laying Date: August 9
Incubation Period: 33 days
Chick Rearing Period: 75 days
Fledging Period: mid-November to peak at November 23
Average Annual Reproductive Success: 1.00 chicks/nest
Nest: 2-3m apart, made in wet, cool, sheltered/hidden hollows and lined with vegetation and/or stones
Age at First Breeding: 5 years
Maximum Lifespan: 20 years
Egg Weight: 99.5 grams
Egg Length: 6.7 cm
Egg Breadth: 5.1 cm
Molt: Birds forage for about two months, gaining approximately 1.6 kg, and then return in February to molt, a process that takes about three weeks, with immatures molting before adults. Males lose approximately 1.9 kg of weight and females 2.3 kg.
Probably cephalopods (squid and octopus), crustaceans, some fish
Dogs, wekas, cats, rats and stoats prey upon eggs and chicks on land. Hooker seals prey upon both fledglings and adults at sea.