Baby rabbits, known as kits, face a high probability of mortality from birth due to their specific biological and behavioral traits. Kits are born altricial—naked, blind, and completely helpless—relying entirely on their mother for warmth and sustenance. The mother rabbit, or doe, employs a unique strategy to avoid leading predators to the young, visiting the shallow, camouflaged nest only once or twice a day for a few minutes to nurse. This strategy leaves the kits alone and exposed for long periods, making them vulnerable to a wide array of threats in the wild.
Apex and Wild Mammalian Hunters
Wild mammalian hunters pose a significant threat, using keen senses and physical tools to locate hidden nests. Canids, such as foxes and coyotes, are primary predators that rely on their acute sense of smell to pinpoint the nest location, often even through soil cover. These hunters frequently dig into the ground to unearth the shallow depression where the kits are buried.
Larger mustelids, including badgers and weasels, also actively seek out rabbit nests, leveraging their ability to dig or their slender bodies to access kits. Badgers are powerful excavators that quickly breach a nest, while smaller predators like stoats and weasels can overpower and consume a litter of vulnerable young.
Terrestrial threats also include various species of snakes. Non-venomous constrictors, such as bull snakes, target nests specifically, consuming the entire litter whole. These reptiles follow scent trails directly into the nest, where the kits are defenseless against the silent, subterranean invasion.
Opportunistic and Avian Nest Raiders
Many baby rabbits succumb to opportunistic predators, particularly those associated with human environments. Domestic and feral house cats are a major source of mortality. They possess a strong, innate hunting drive that compels them to stalk and kill small prey, often killing kits for instinct or sport and leaving the bodies uneaten.
Domestic dogs, especially those with a high prey drive, also pose a substantial threat. They often detect and destroy nests during backyard exploration; the instinct to chase and dig leads to fatal outcomes even if the kits are not consumed. Smaller, nocturnal mammals like raccoons, skunks, and opossums are also drawn to suburban areas. Raccoons are dexterous raiders that readily consume kits if they stumble upon a nest.
Avian predators pose an aerial threat, swooping down to snatch exposed kits. Large raptors, including great horned owls and red-tailed hawks, use keen eyesight and speed to capture young rabbits from above. Corvids, such as crows and ravens, are also opportunistic nest raiders that prey on vulnerable kits.
Environmental and Human-Caused Mortality
Non-predatory factors account for a considerable portion of baby rabbit deaths, often involving environmental stress, maternal failures, or disease.
Environmental Stress
Severe weather is a major cause of environmental mortality. Heavy or prolonged rainfall can flood the shallow, ground-level nests and drown the kits. Extremely cold temperatures or sudden drops can also lead to hypothermia, as kits cannot regulate their own body temperature for the first weeks of life.
Maternal Issues and Disease
Maternal issues are frequently cited in pre-weaning deaths, including insufficient milk supply or the mother’s failure to adequately care for the young. In some cases, a doe may resort to cannibalism, often linked to high stress, nutritional deficiencies, or kits being born outside the nest.
Diseases and parasites also take a heavy toll on the vulnerable immune systems of kits. Viral diseases like myxomatosis and bacterial infections (such as Staphylococcus aureus or E. coli) can spread rapidly and be fatal. Parasitic infestations, including botfly larvae and internal parasites like coccidia, can weaken or kill kits before they are old enough to leave the nest.
Unintentional Human Actions
Unintentional human actions contribute significantly to mortality, especially where nests are built in lawns or gardens. Accidental deaths frequently occur from common activities like mowing, tilling, or using gardening equipment over a concealed nest. The application of herbicides and pesticides in yards can also expose kits to toxic chemicals, leading to poisoning or developmental failure.