Antwerp Zoo has confirmed that one of its chimpanzees is pregnant. Eighteen-year-old Marit is expecting her baby in December or January. If all goes well, it will be the first chimp to be born at the zoo in more than 30 years.
Until two years ago, the zoo’s two females, Marit and Mia, were given the contraceptive pill. Zookeepers were then given permission from the European authorities to expand their group of chimpanzees.
“As in humans, it can take a while for contraception to fully wear off,” says keeper Sarah Lafaut. “Since they stopped taking the pill, we tested monthly to see if they were pregnant.” There was great joy among the zookeepers when the latest test was positive.
Visitors to the zoo won't notice that Marit is pregnant any time soon, says Lafaut. “A baby chimp weighs only 1.5kg, so she will only have a small belly at the end of the pregnancy.”
The father is not yet known. Lafaut: “The chances are it will be Tambuzi or Tuma. They are the dominant chimpanzees in the group.” They will only know for sure at the zoo after the birth, when a DNA test will be done on the baby’s hair.
The days when we were a museum collection full of animals are long gone
Zoos around the world work together to maintain the population of a particular species, with coordinators deciding which animals are allowed to breed where.
Most animals at Antwerp Zoo are given contraception to prevent pregnancies, with apes given the human contraceptive pill. “The days when we were a museum collection full of animals are long gone,” says Lafaut. “We don’t want our animals to breed indefinitely. That is not desirable.”
In other animals where males and females cohabitate, zoos have to be more creative. “Lions and smaller monkeys, for example, have a hormone rod implanted in their arm or paw. The rod has to be replaced every year or six months depending on the species,” says Lafaut. “In chimpanzees, that method doesn't work because they can feel there is something in their arm and they just scratch it out.”