Penguin breeding in Edinburgh

The Scottish National Zoological Park at Edinburgh has been notably successful in keeping and breeding penguins. It is happy in possessing as a friend and benefactor, Mr Theodore E. Salvesen, head of the firm of Christian Salvesen & Co., Leith, to whose interest and generosity it owes the great number of penguins it has possessed. Of the seventeen known species of penguins, seven are represented in the Park, the king (Aptenodytes patagonica Miller), gentu (Pygoscelis papua Forster), ringed (Pygoscelis antarctica Forster), macaroni (Catarrhactes chrysolophus Brandt), Magellan (Spheniscus magellanicus Forster), Peruvian (Spheniscus humboldti Meyen) and black-footed (Spheniscus demersus L.). The collection has risen as high in number as 180 individuals, but at present numbers only about 70. The first penguins received in the Park were three king penguins which arrived from South Georgia in January 1914. One of these three was fully adult and was therefore not less than two years old at the time of its arrival. I am happy to say that it is still alive. It is a female and was the mother of the first chick hatched in the Park. The other two which came at that time were in the brown nestling plumage and were probably, therefore, just about a year old when they arrived. One of these young ones, a male, was, after it had moulted, much courted by the adult, but in spite of the attention paid to it by the adult female in the years 1915, 1916 and 1917, it showed little inclination to respond and was, I concluded, not sexually mature at that time. In 1918 the female laid an egg which was not fertile. On the 1st of September 1919 another egg was laid. This egg was incubated by the parents, both birds taking turns with the egg though the greater part of the work of incubation seemed to fall upon the male. The king penguin makes no nest, but holds its single egg on the feet and covers it with the skin and feathers of the lower part of the abdomen. There is nothing in the way of a pouch for brooding the egg and the egg is held between the two feet placed close together and the lower part of the body. The penguin is able to move about in an awkward shuffling manner with the egg held on its feet, and so firmly can it be held that the bird can even climb a rock, or fall from a rock, without losing its grip of the egg. On the 26th of October the egg was found to be chipped, and on the second day after that the young penguin emerged. The king penguin chick, when newly hatched, shows traces, especially on the head, of a natal coat of white down-like feathers. This disappears within two or three days and the growth begins of a brown nestling coat. This seems to suggest that the king penguin chicks were at one time clothed in a white nestling coat like that of the emperor penguin, but that either a movement to more northerly breeding grounds, or a change to a less glacial climate of the established breeding ground, induced a corresponding change in the colour of the nestling coat. The chick is, like the young of all penguins, fed on pre-digested fish which it takes from the throat of the parent bird. It has been noted that for a day or two before the egg hatches the adult bird is disinclined to feed, perhaps so that there may be a supply of fully digested food available for the very small chick when it first appears. The parent birds soon, however, begin to feed more greedily again. The food regurgitated is at first quite liquid, but in a few days quite large pieces of fish are brought back. The chick has a warbling flute-like call which it utters when it wishes to feed. The growth of the chick is fairly rapid, though not so rapid as in the case of the smaller penguins. By the time the chick was eight weeks old it had attained so large a size and was making such demands upon the parents for food that they seemed to be growing weak, so the experiment was made of giving the chick its own allowance of fish, small herring and whiting being used for the purpose. The chick took very readily to the change and was soon taking its 14 to 20 herrings a day. This enabled the parent birds to recover condition, but one wonders how wild king penguins manage to endure the strain of finding sufficient food, not only for themselves but for the chick, as they must do, until it is about a year old. In due course this chick was reared and it went into its first moult in April 1920, about six months after it was hatched. In the following year, 1920, two pairs of king penguins laid eggs but neither egg hatched. The same thing happened the next year. More adults had been received from South Georgia and in 1922 three eggs were laid and two hatched, but each of the chicks died when it was just three days old. The year 1923 brought a similar experience. I was puzzled to understand why these chicks died so quickly and I reviewed the circumstances and compared them with those attending the hatching and rearing of the first chick. I could perceive no difference in conditions or treatment except one, that while the first successful egg had been laid and incubated in the late autumn, when the weather was bleak and wet, subsequent eggs had been laid in June and the chicks hatched in August when the weather was hot and dry. In order to compensate for this difference I arranged, in 1924, a fine spray in the penguins’ enclosure which kept a portion of rock always wet. When the first egg was laid in June 1924, this spray was turned on and the incubating birds kept pretty much within its range. A second egg also was laid in 1924 and both these eggs hatched and the chicks were reared. I concluded, therefore, that the spray had solved the problem and since then I have a spray in each of the penguin enclosures and keep the spray going whenever the weather is hot. One of the 1924 chicks is still alive although the other, and that of 1919, are both dead. Meantime, in 1925, the male of the original pair had died and there was no fertile egg in 1926, but in the years 1927 to 1932 inclusive, a chick was hatched each year and several of them, but not all were reared. In 1932, a consignment of 16 adult penguins was received from South Georgia and these I have kept in a separate enclosure so that they form a second colony. They also have bred successfully and in all twenty two king penguin chicks have been hatched and reared in the Park. Four of them are being reared at the present time. As many as nine king penguins were incubating eggs at one time in the Park last August, but only four of the eggs hatched. So much for the king penguins.