Rabbit moms have a never-ending job, and can birth a new litter every 30 days! In order to keep their babies alive, moms have to keep their distance.
The processes of ovulation and copulation are coupled in female rabbits - meaning that each time she has sex, a baby enters her womb. The gestational period in rabbits is a mere 30 days, and the litter size is usually three to six kits. Female rabbits provide very little in the way of direct care to their kits. Each time she’s near birth, a rabbit mother will assemble a comfortable nest in a hidden burrow using vegetation, her own loose fur and some fecal pellets.
The babies are then born in the burrow, each about one minute after the next. Once the babies are clean and safe, mom leaves them in the burrow and seals up the entrance with loose vegetation. For the next two weeks, she will only return once a day for just for a few minutes to nurse her babies. Rabbit milk is extremely rich. It contains nearly four times the amount of fat and protein as cow’s milk, and almost three times the energy content. The rich milk is incredibly important since rabbit nursing is far less frequent than many other mammals.
Rabbit mothers staying away from their young is a strategy to keep the babies safe. Rabbits are an easy target for a wide range of predatory birds and mammals, so frequent trips to the burrow could showcase the location of offspring. Because their mother isn’t near, newborn rabbit siblings quickly form close social bonds by staying close together for warmth and keeping each other clean.
The kits will stay in their burrow for about three weeks, but before they leave, they begin the transition to solid food. Meaning, they no longer need their mother to survive. The bunnies start this process by consuming the vegetation of their nest - and they will also consume fecal pellets. The pellets contain important bacteria that help to establish a healthy microbiome in their stomachs - essential for digestion in the outside world.
When the kits emerge from the nest, it’s a signal that mom’s job is done, at least for that group. She is most likely already pregnant again with a new litter and hard at work constructing another nest elsewhere.