Spring has finally arrived in the northern hemisphere, sweeping winter away with flowers, outdoor activities, and cute babies. While it’s safe to assume that human younglings will be outside in higher numbers, of course we’re talking about baby animals. In the springtime it’s not unusual to find babies such as chicks and squirrels separated from their mothers, but the protocol for what to do about it depends on the species—and the females’ motherly instinct.
In the case of opossum mothers, that instinct is comically low. If given the opportunity, squirrel and raccoon mothers will take their babies back—but these marsupial mothers are less forgiving.
“With possums, we generally say that reuniting is not possible, because mom generally has just kept going,” Priya Patel, wildlife veterinarian at Massachusetts’ New England Wildlife Center, tells Popular Science. It’s worth clarifying that while possums and opossums are sometimes used interchangeably, they are technically two different animals, and here we’re talking about Virginia opossums (Didelphis virginiana), North America’s only native marsupial.
Opossum babies weigh just 0.13 to 0.16 grams at birth. The newborns immediately move into the mother’s pouch, where they attach to her nipples and are quite literally stuck for 55 to 60 days, after which they re-emerge into the world.
“The most common period we have people calling us about baby possums is generally about right before they’re two months old, when they’re starting to come out of the pouch and attach onto mom,” Patel explains. That’s when “you see all those pictures of them clinging onto her as she’s moving around, and they’re starting the weaning phase at that point and starting to explore, but they fall off of her and she doesn’t typically wait for them.”
In mom’s defense, opossum babies don’t have the clearest call for help—they make sneezing sounds. If she’s nearby, she might pause to take them back, but Patel has only heard of one potential case of a mother looking for her lost babies.
As such, you should call a licensed wildlife rehabber or wildlife hospital if you come across one or more opossum babies on their own. In the meantime, don’t try to feed them—baby animals have a particular diet, and it could upset their gastrointestinal system, Patel explains.
You might not always be asked to bring the animal in for care. If the individual is around 10 inches long not including the tail, it’s usually grown enough to be independent.
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