By Holland Quick
Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrata
Class: Aves
Order: Sphenisciformes
Family: Spheniscidae
Genus: Eudyptula
Species: Eudyptula minor
Geographic Range
Eudyptula minor is found along the shore of Southern Australia, including offshore islands, to New Zealand (Lindsey 1986).
Biogeographic Regions:
australian (native).
Habitat
Eudyptula minor prefers sandy, rocky beaches for landing at night and for nesting. The little penguin occurs in the temperate seas of Australia, feeding mainly in inshore waters around the mainland and offshore islands. Most colonies are found on sandy, rocky islands, around bases of cliffs, or near sand dunes (Lindsey 1986).
Terrestrial Biomes:
chaparral .
Aquatic Biomes:
coastal .
Physical Description
Mass
900 g (average)
(31.68 oz)
Eudyptula minor is a small, flightless bird. The little penguin has a silvery bluish-black dorsum, from the top of the head to the tail. The face and neck area is a lighter gray fading into white moving down. The underparts are white, including the undersides of its flippers. Eudyptula minor has a dark gray bill and silvery-gray eyes. The feet are white on top, with black webs and soles. No seasonal variation has been recorded, although there are a few subspecies with slightly different coloration. One such subspecies has entirely white flippers.
Eudyptula minor is the smallest of all penguins, with a length of 375-425 mm, and an average flipper size of 104 mm. These animals are slightly dimorphic with the male somewhat larger than the female, with a larger, deeper bill.
Fledgelings are similar to the adults, but with a shorter, slimmer bill. The dorsal feathers are a little lighter with a more blue appearance, but fade with wear (Lindsey 1986; Marchant & Higggins 1990).
Some key physical features:
endothermic ; bilateral symmetry.
Reproduction
Breeding occurs mainly on off shore islands, and in some remote parts of the Southern Australian shore. The breeding season for E. minor is between August and December, with peak egg laying in August and November. The male and female copulate close to their nest, which usually is in a natural burrow or rock pile. In most cases the little penguin lays 1-2 white eggs, 3-5 days apart. Incubation begins after first egg is laid, but only partially until after the laying of the second egg, with both sexes shifting on and off every few days.
Eggs hatch within approximately 36 days, and chicks are semi-altricial, weighing about 40 g. They are brooded for first 10 days of life, and guarded continuously for the next 1-3 weeks, again with male and female alternating. At 3-4 weeks the chicks are guarded only at night, and then in later stages they are only visited at night by a parent for feeding.
Fledgling young (90% of adult weight) leave the nest for 2-3 days at a time, and then finally permanently. Eudyptula minor reaches sexual maturity after about three years of life in both sexes (Marchant & Higgins 1990; Heather & Robertson 1997).
Key reproductive features:
iteroparous ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; oviparous.
Behavior
Eudyptula minor is a social bird, and is the most nocturnal of all penguin species. During the day it is either hunting at sea or in its nest sleeping. Little penguins live in loose colonies, composed of birds of all ages. They form small, very vocal groups when coming ashore at night, but then disperse to respective territories. The little penguin has a surprisingly diverse array of visual displays for many social situations. For example, fighting stances, warding off unfamiliar birds, and mating displays.
The little penguin has large range of calls, in addition to its visual displays. Sounds range from soft mewing notes, to loud screams, to growling, and even trumpeting calls.
Individuals undergo a complete body molt sometime from December to March, after the breeding season. This usually takes place at the breeding site and lasts from 10-18 days.
Eudyptula minor has a distinct sexual behavior. The male stands in a distinctive stance with flippers up, bill also pointed upward, accompanied by a braying call to attract a female. He will often build a nest to court her. Once male and female are mated they form a long-term monogamous pair, usually for life. Although they do not hunt for food together during the day they both come back to their shared nest at night.
Once a pair has bred and laid eggs both raise young together. Although eggs may sometimes be deserted there is no record of deserted young. Food is transferred directly from parent to young through regurgitation. Aggression between parents and children is rare, and only occurs when fully fledged young are driven from the nest. Adults are, however, aggressive toward young other than their own if approached for food. Fledglings usually migrate to different areas after becoming independent of their parents (Marchant & Higgins 1990; Heather & Robertson 1997).
Food Habits
Eudyptula minor eats small fish (10-35 mm), some cephalopods, including arrow squids and octopi, and less often small crustaceans.
Much of the feeding of E. minor takes place within the top 5 m of the surface of the ocean. However, the mean dive is appoximately 30m, with a maximum recorded dive of 69 m. The little penguin is usually found feeding singly.
Prey is caught with a pursuit-diving technique. When E. minor sights a school of fish it will circle around the school and then dive into the middle, grabbing a fish on its way through. In some cases the penguin will seek out stragglers from the school or eat solitary fish, always swallowing underwater.
The penguin feeds daily, roughly from dawn until dusk. An irregularity in food availability may explain the bird's low metabolic rate, as compared to other species (Marchant & Higgins 1990; Heather & Robertson 1997).
Economic Importance for Humans: Positive
Eudyptula minor is common in and around Australia and is a relatively familiar species to the people there. Tourists gather to see the nightly "penguin parade", as the penguins noisily come ashore after a day's feeding. They are relatively common in inshore waters where pleasure crafts and other boats may glimpse the small bird (Lindsey 1986).
Conservation Status
IUCN Red List:
Least Concern.
US Federal List:
No special status.
CITES:
No special status.
This species is a proctected native of Australia. It is common on remote islands and in a few areas of the mainland, where not disturbed by dogs, cats, and humans. Populations undergo severe crashes in some years, however, with many dead birds washing ashore. This is probably a result of food shortage or biotoxins.
This species is severly depleted where human populations have increased. They may be killed in fisherman's nets, when set too close to shore they inhabit, and also by domestic dogs (Heather & Robertson 1997; Parks and Wildlife Service, Tasmania 1998)
Other Comments
One important fact about Eudyptula minor is that there are five to six subspecies, which are debated by scientists. There are slight color variations between some of the subspecies. Generally there is accepted to be a cline around the New Zealand region (Lindsey 1986).
Contributors
Holland Quick (author), University of Michigan.
Phil Myers (editor), Museum of Zoology, University of Michigan.
References
Heather, B., H. Robertson. 1997. The Field Guide to the Birds of New Zealand. New York: Oxford University Press.
Lindsey, T. 1986. The Seabirds of Australia. London: Angus & Robertson Publishers.
Marchant, S., P. Higgins. 1990. Handbook of Australian, New Zealand & Antarctic Birds. Melbourne, Australia: Oxford University Press.
Parks and Wildlife Service, Tasmania, 1998. "Wildlife of Tasmania" (On-line). Accessed March 23, 2001 at http://www.parks.tas.gov.au/wildlife/birds/penguin.
2009/04/19 02:45:24.281 GMT-4
Citation:
Quick, H. 2001. "Eudyptula minor" (On-line), Animal Diversity Web. Accessed April 24, 2009 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Eudyptula_minor.html.
Information courtesy of Animal Diversity WEb @
http://animaldiversity.ummz.umich.edu/site/accounts/information/Eudyptula_minor.html
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