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Tone (1970) 16: 115-1 19. 115 A LITTLE BLUE PENGUIN IN CAPTIVITY by Jennifer J. Bedford. * In spite of many years of study, very little is known of the natural history and behaviour of some of our familiar vertebrates. The enormous store of new information gained by Lack (1939) on robins, Neal (1948) on badgers, and the more detailed findings of Lorenz (1952) and Tinbergen (1965) shows how much can be gained by careful observation and recording. Hinde's (1966) statement that " a descriptive account of the ways in which behaviour changes with age might seem to be a necessary preparation for an analysis of the factors which influence these changes, but in fact really detailed descriptions of the development of behaviour over even a small part of the life span are rather rare." is surprisingly only too true. In a world where science appears all-knowing and all- powerful it seems strange to find the large gaps revealed by asking simple questions. This was brought home to us recently when we found a Little Blue Penguin (Eudyptula minor novaehollandiae) washed up exhausted in the surf just south of Kawerua. It still had young down feathers and was waterlogged. We brought it back to Auckland, fed it, and hoped to find whether it could be brought back to a healthy state and released. It soon became apparent that simple questions could not be answered. For instance, how oily should its feathers be? How wet should it get: should only the outer layer of feathers get wet and the inner down remain dry or should the water run off the bird as it does off a clean plate of glass? Does the mother teach it to feed or is feeding behaviour innate? Will it, if reared by humans, attach itself to them whenever it sees one? Will it attempt to return to where it was fed? (Instances have been known where a little blue penguin has walked several miles to return to its own nesting site (Cassie, 1970 pers. comm.)). These basic questions about behaviour could not be answered from the recorded knowledge — spoken or written - in New Zealand ornithology or behaviour. We found out by trial and error and a little luck. While keeping the penguin for two weeks until we felt that it would be able to fend for itself when let go, it passed through a stage in its development in which it matured quickly and developed in a sense from being a chick to a young adult. Our penguin was apparently one of the September/October chicks from last year (1969) and was about three months old. It had several large bird ticks on its chin and head but they fell off after a couple of days once they were fully gorged and distended. They were then about a * Department of Zoology, University of Auckland.

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Tone (1970) 16: 115-1 19. 115

A L I T T L E B L U E P E N G U I N IN C A P T I V I T Y

by Jenni fer J . Bedford . *

In sp i te of many years of s tudy , very l i t t l e i s known of the natural history and behaviour of some of our fami l iar vertebrates. T h e enormous store of new information gained by L a c k (1939) on robins , N e a l (1948) on badgers, and the more deta i led f indings of Lorenz (1952) and Tinbergen (1965) shows how much can be gained by care fu l observation and recording. Hinde ' s (1966) statement that " a descr ip t ive account of the ways in w h i c h behaviour changes with age might seem to be a necessary preparation for an a n a l y s i s of the factors which influence these changes , but in fact rea l ly deta i led descr ipt ions of the development of behaviour over even a s m a l l part of the l i fe span are rather r a r e . " i s surpr i s ing ly only too true. In a world where s c i ence appears a l l - k n o w i n g and a l l -powerful it seems strange to f ind the large gaps revealed by a s k i n g s imple quest ions .

T h i s was brought home to us recently when we found a L i t t l e B l u e Penguin (Eudyptula minor novaehollandiae) washed up exhausted in the sur f just south of Kawerua . It s t i l l had young down feathers and was waterlogged. We brought it back to A u c k l a n d , fed i t , and hoped to f ind whether it could be brought back to a healthy state and re leased . It soon became apparent that s imple questions could not be answered. F o r instance , how o i l y should its feathers be? How wet should it get: should only the outer layer of feathers get wet and the inner down remain dry or should the water run off the bird as it does off a c l e a n plate of g lass? Does the mother teach it to feed or is feeding behaviour innate? W i l l i t , i f reared by humans, attach i t se l f to them whenever it sees one? W i l l it attempt to return to where it was fed? (Instances have been known where a l i t t l e blue penguin has walked severa l miles to return to its own nest ing s i t e ( C a s s i e , 1970 — pers. comm.)). These bas ic questions about behaviour could not be answered from the recorded knowledge — spoken or written - in New Zea land ornithology or behaviour. We found out by t r i a l and error and a l i t t l e luck .

While keeping the penguin for two weeks unt i l we felt that it would be able to fend for i t se l f when let go, it passed through a stage in its development in which it matured q u i c k l y and developed in a sense from being a c h i c k to a young adult .

Our penguin was apparently one of the September/October c h i c k s from last year (1969) a n d was about three months o ld . It had severa l large bird t i c k s on its c h i n and head but they f e l l off after a couple of days once they were fu l l y gorged and d is tended . They were then about a

* Department of Zoology, University of Auckland.

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•A

FIG. I: The Little Blue Penguin.

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quarter to a third of an inch long. Not unt i l s evera l days later d id we d iscover that there were about a dozen of these on the inside of the b i l l and throat — some dead and some a l i v e . Once these were removed the penguin seemed to be much happier; it ate a lot more and showed many s igns of becoming healthier and regaining strength. Obv ious ly s w a l l o w ­ing had been both di f f i cult and uncomfortable for i t . It a l s o had many fleas and mites which were probably acquired in the burrow during its terrestr ia l l i fe as a young c h i c k .

We fed it on f ish ba i t , s m a l l f i s h , and shr imps ; it would take no old or tainted f i sh nor s l imy e e l s . A t f irst our bird had to be force-fed: its legs and b e l l y held f i rmly , i t s f l ippers out of the way , its b i l l held wide open; the f i sh was then forced w e l l down its throat. T h e tongue is " b a r b e d " so that it is l i k e a one way conveyor belt and the f i sh can only go down. Normally penguins feed and swal l ow under water which may be why this one was s o c lumsy when handl ing i ts food on land . The bird ate a lot — up to two large tarak ih i f i l l e t s a day — and put on weight q u i c k l y . Only once did it regurgitate its food, which was then a l l soft but undigested presumably as it had only been stored in the crop. On that occas ion it a l s o lost much weight which it very q u i c k l y regained in about a day. The penguin would make s h r i l l t r i l l i n g noises and quiver its b i l l when it was hungry. Perhaps under natural condit ions this a c t i v i t y attracts the attention of the parent. A s the bird became older i t would accept only large pieces of f i sh and f i n a l l y it would grab the f i sh i n the t ip of its b i l l and f l ip it back down its throat. T h i s change happened very q u i c k l y in one or two days ; and after this the bird became more aggres­s i v e . It seemed quite obvious to us that feeding would not be learnt from the mother. T h i s was further borne out in the way it would ca t ch i n s e c t s . The penguin would fo l low moving f l ies very c l o s e l y wi th i ts eyes , chase them around, snapping inaccurately at them, but f i n a l l y ca t ch ing them. It improved with pract i ce .

Movements of the penguin on land looked c lumsy and c o m i c a l but were in fact ag i l e and e f f i c ient . It would run very fast w i th its f l ippers he ld out for balance and learnt to assoc iate human legs w i th food. It would fo l low " q u a c k i n g " after the f irst pair of legs it saw . A s it became older and stronger it would watch where it was go ing and not tumble down steps but would care fu l ly jump down. One remarkable fact was that it would jump up a step almost equa l to its own height from standing and do th is three or four times in s u c c e s s i o n .

T h e penguin d id not appear to be necessar i l y nocturnal . Although some authors (O l iver , 1930; R i c h d a l e , 1957) say the penguin is not no i sy , this one made a variety of no i ses : a baby t r i l l i n g noise in response to

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food, a more adult quack, a sobbing sound at the back of its throat, and later a more aggress ive h i s s . When rest ing it would l ie flat on its be l l y and seemed to resent being conf ined. On the other hand it would a lways run under some object for protection and would s i t peering watchful ly from a safe p lace .

Penguins can be seen to best advantage in the water where they are very beauti ful and a g i l e . On the surface they w i l l paddle about with the f l ippers hardly moving and the feet employed for s teer ing . A s our bird became older it spent more time in the water. Its down and the wax around the new q u i l l s was lost . A t the same time, as the feathers were o i led more, the water f e l l readi ly from its back. Adul t s during moulting tend to stay out of the water unt i l the new feathers are fu l ly o i led and the same seems true of the young b i rd . Our bird would probably have remained much longer in i ts nest ing burrow, from which it was perhaps prematurely e jected .

With growing fami l iar i ty with the water, the penguin would s c u l l round whi le per i od i ca l l y r o l l ing on i ts s i d e , patt ing and s p l a s h i n g i ts under s ide with one of i ts f l ippers . It appeared a l s o to inflate and deflate i t se l f to contro l its buoyancy. During d i v i n g , i ts shape — apparently so c o m i c a l on land — became smoothly s tream-l ined , enabl ing the bird to cut through the water with ease . It was then propelled mainly by broad strokes of i t s f l ippers , with the feet held re laxed and t r a i l i n g behind. A i r would be expel led from the b i l l at the beginning of a d ive , wi th apparent reduction in buoyancy. B o t h in fresh and sa l t water, the bird would drink a lot and would defaecate frequently, as it did too often on land . The bird seemed to d i s l i k e being sp lashed on the head with water. It was reluctant to dive into s t i l l water, but as soon as it was released it immediately turned and dived through the breaking waves , rather than r id ing over them.

A s may be seen , much can be learned from such elementary observations, keeping a l ive animal for a few weeks or s imp ly just watching it in the f i e l d . Though we know much about the plumage, nest ing , migration, and habitats of common New Zealand b i r d s , important gaps s t i l l remain. Perhaps not only Lorenz and Tinbergen, but people l i k e G a v i n M a x w e l l and Gerald D u r r e l l can show us facts about animals that a n a l y t i c a l and s c i e n t i f i c work w i l l never do . Without an in tu i t ive " f e e l i n g " for animals many of our exact studies can become s t e r i l e , whereas the former engenders a sympathy going far beyond se l f -centred human a f fa i rs .

A C K N O W L E D G E M E N T S

I w i s h to thank Dr . J . P . Leader and Professor J . E . Morton for their enthusiast ic support and c r i t i c i s m of this a r t i c l e .

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HINDE, R.A. 1966

L A C K , D. 1939

L O R E N Z , K . Z . 1952

N E A L , E . 1949 O L I V E R , W.R.B. 1930 R I C H D A L E , L . E . 1956 T H O R P E , W.H. 1956

T I N B E R G E N , N. 1965

R E F E R E N C E S

"Animal Behaviour — a Synthesis of Ethology and Comparative psychology. " McGraw-Hill Book Co. The behaviour of the robin. Proc. Zool. Soc. Lond. A. 109: 169-178. " K i n g Solomon's R i n g " University Paperbacks. Methuen & Co. " T h e Badger." New Naturalist Monograph Series. "New Zealand B i r d s . " A . H . & A.W. Reed. " A Population Study of Penguins. " O . U . P . "Learning and Instinct in Animals . " Methuen & Co. "Animal Behaviour." Time-Life Books, Chicago.