The smallest penguin
The blue or little penguin (Eudyptula minor), also known in Maori as korora, can be found in many places around New Zealand and Southern Australia and is the world's smallest penguin. They only come ashore under the cover of darkness and live underground in burrows. Although quite common, its small size and unusual habits make it rarely seen.
The blue penguin stands just 25 cm tall and weighs a little over 1 kilogram. The plumage is slate-blue with a bright white belly. Juveniles are indistinguishable from adults. Both sexes are alike, although the male is a little heavier and usually has a larger bill.
There are several distinct races of blue penguins and some argue that they should be split up into sub-species. Perhaps the most distinct is the "white-flippered" penguin of Canterbury, however genetic tests have shown it not to be as distinct as its plumage would suggest.
Blue penguins make a variety of calls
to keep in contact at sea (barks), declare territory and advertise for
mates (brays) and to let the neighbours know they are home (croon). The
only call chicks make is a high pitch peeping as they beg for food.
Blue penguins breed underground in burrows or natural holes, although
they will make use of any man-made cavity. Near human habitation it is
not uncommon to find them nesting under buildings, stacks of timber or
even railway tracks. Artificial nest boxes
are readily adopted.
Blue penguins in New Zealand have rather variable breeding seasons. The
core egg-laying period for most of New Zealand is September to November,
and only one clutch is laid. In good food years, blue penguins in Otago
will egg-lay from May to February, with many pairs raising two clutches
Usually two eggs are laid and are incubated for 36 days, with both parents
sharing the incubation and feeding duties. The chicks are guarded by one
parent for the first 2-3 weeks, after which both parents must go to sea
to keep up the supply of fish. Chick growth is rapid, with adult weight
(1000g) being achieved in 4-5 weeks. Chicks usually fledge at 8 weeks
and are independent from then on.
Blue penguins usually breed for the first time at 2-3 years of age. Long
term partnerships are the norm, but divorce is not uncommon. There is
a high rate of juvenile mortality, but individuals can reach up to 25
years of age.
Blue penguins are very faithful to their home site. Chicks will often
return to within a few metres of where they were raised and once settled
in an area never move away. A small number (<1%) of juveniles disperse
to other breeding sites.
Diet and feeding
Blue penguins feed on a variety of surface schooling fish, squid and crustaceans.
Although dive depths of 60m have been recorded, 10-20m is more common.
The average dive time is 24 seconds. Blue penguins usually feed within
25km of the coast and may make daily round-trips of up to 75km. Long winter
feeding trips of up to 750 km (one way) have been recorded. Blue penguins
can reach speeds of up to 6km/hr underwater. More
Predation by introduced mustelids (ferrets, stoats, and weasels) has decimated many mainland colonies. In publicly accessible areas, dogs have been major predators - particularly of penguins returning from the sea. At Chatham and Stewart Islands, the southern brown skua also attacks blue penguins returning from the sea. More >>>
The population and range of the species has been declining in areas not protected from predation, resulting in the NZ Department of Conservation ranking the blue penguin as "Lower risk - near threatened".
Where predator control is in place, populations have been stable or increasing. Nest boxes have been useful in some habitat restoration efforts.
Because blue penguins are only active on land at night they can be hard to view, however there are places one can view them. More >>>