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Jack Marks His 30th Birthday March 11, 2021
Hatch Day: March 11, 1991

Humboldt penguin Jack

The Zoo celebrates the 30th birthday of Jack, one of our Humboldt penguin flock members. Jack is in the top 20 oldest penguins in North America! The oldest confirmed Humboldt penguin living in human care lived to be 36 years old. MCZ’s own male Humboldt, Arisco, lived to be 34 years old. So, as Jack turns 30 years old, this marks quite a milestone, and speaks to the high level of care and attention he receives at the Milwaukee County Zoo! Keepers will be celebrating his birthday with his favorite treats!

Fun facts:

  • Humboldt penguin Jack
    Jack is shown here on the right, with a green band.
    Jack hatched at the Milwaukee County Zoo.
  • He is banded green right. His mate is Eva (banded green left).
  • Jack and Eva had our first surviving Humboldt penguin chick (Titi) after West Nile Virus overcame our flock in 2002. Titi was hatched in 2006 and transferred to Sea World San Diego for breeding.
  • Jack and Eva are also the parents of Penelope (banded orange left), Liberty (no longer with us) and Lilly (banded red left).
  • The pair is also the grandparents of Thistle (banded light purple left), Daisy (now at the Brookfield Zoo in Illinois), Anchovy (banded pink left), River (now at the St. Louis Zoo) and Wallace (banded white right).
  • He is an excellent dad and likes to spend time with his chicks once they fledge onto exhibit.
  • Humboldt penguin JackJack is scale trained so keepers can record regular weights. He weighs about 9 ½ pounds which is almost the same weight as a sack of potatoes.
  • His buddies are Farley (banded orange right), and Houdini (banded grey right).
  • Jack can be one of our shyer penguins.
  • He likes to play with toys in the pool; his favorites are the boomer ball, confetti bottle, bubbles and the purple octopus. He especially likes to watch cartoons when the keepers play them. The toys and cartoons are part of animal enrichment programs which keep the animals active and engaged and also serves to alleviate boredom.
  • His favorite fish treats are silversides, herring, smelt and rainbow trout.