THE CARE & FEEDING OF JOHN BALL ZOO'S BABY PENGUINS.
John Ball Zoo’s penguin species is the Magellanic or Spheniscus magellanicus. They are native to Chile, Argentina and the Falkland Islands in the southern hemisphere. As wild birds they would begin breeding about September, but we keep our flock on a light cycle that mimics the northern hemisphere (particularly Grand Rapids) so ours begin breeding in March. Females almost always lay 2 eggs, which then take about 43 days to hatch. This year we took all of the penguin eggs when they were freshly layed, and incubated them artificially. The parents were given weighted plastic "dummy" eggs so that they would continue nesting. When the eggs were ready to hatch we replaced the dummy eggs with the real thing and let the parents raise most of the chicks. It was necessary, however, to hand raise two of the chicks that were the most genetically valuable (having the genes least represented in the captive population). Hand reared chicks like the one in the video are fed fillets of mackerel, herring and capelin, as well as krill. We also make a milkshake-like "formula" each morning consisting of herring fillets, krill, water, half-and-half, an enzyme that the chicks need in order to digest lactose, two dietary supplements, and a multivitamin formulated specially for our penguins. We then coat the fillets with formula, heat the whole thing to about 90 degrees (yum!) and feed the chicks. Parent penguins feed by regurgitating into chicks' beaks so we need to try to mimic that action with our hands. There is an acquired skill there. For the first two weeks the chicks eat seven times per day. At thirteen days of age they switch to four feedings per day. Day 29 brings only three feedings (and no more formula!) and at 49 days the chicks are fed only twice (just like the adults). As the chicks grow the food offered becomes bigger, and after 21 days they receive whole or half fish rather than fillets. The chick in the video is only 17 days old, and at that age they are still very fragile and unsteady. They're barely able to stand upright and still need to be kept in a heated isolet because they can't fully regulate their body temperatures (parent birds use their own body heat to do this for the chicks).
At each feeding chicks are offered 10% of their morning body weight (not counting formula), and they are weighed before and after each feeding to gauge how much was eaten. Chicks of the age of the one in the video generally eat most or all of the food offered (imagine eating 70% of your body weight daily).
John Ball Zoo began breeding penguins in 1988 and has developed into one of the most successful programs in the country. In that time we have successfully raised 61 total birds - many of which have gone on to populate other zoos such as Sea World, Shedd Aquarium and St. Louis Zoo. I've been at JBZ for eighteen years, making this my nineteenth breeding season and in that time I've raised or helped raise 47.