The quiet of night is often punctuated by unexpected squeaks. These high-pitched noises frequently lead to questions about their source. Identifying the creatures responsible can range from common household pests to elusive wildlife, each with unique reasons for their sounds.
Rodent Squeaks
Mice are common nocturnal rodents known for their distinct high-pitched squeaks. These vocalizations serve as a primary means of communication within their colonies. If mice are heard squeaking in a home’s walls, attics, or basements, it indicates communication among them, suggesting more than a single mouse.
Mice produce both ultrasonic and audible sounds, though humans cannot hear all their pitches. Their squeaking can vary in pitch and frequency, conveying different messages. For example, squeaks become louder when they find food and faster during mating. Male mice use intricate squeak patterns during courtship, and pups squeak for their mothers when she leaves or returns. Female mice also squeak frequently when near other females.
Rats, while generally quieter than mice, also produce squeaks, chirps, and hisses. Most of their vocal communication occurs in the ultrasonic range, making it undetectable to human ears without specialized equipment. When audible, a rat’s squeak often signifies fear or pain, similar to a scream. They may also squeak during play or mild protest, with longer, more drawn-out squeaks indicating severe protest or distress.
Voles, small mouse-like rodents, also emit high-pitched chirps, particularly when frightened or in danger. Many of their sounds are at frequencies beyond human hearing. These squeaks often serve as warning signals.
Mammalian Night Sounds
Beyond common rodents, other nocturnal mammals contribute to the array of high-pitched sounds heard at night. Bats, for instance, are renowned for their sophisticated use of sound. They navigate and locate prey using echolocation, emitting high-frequency sound pulses through their mouth or nose and listening for the echoes.
While most bat echolocation calls are ultrasonic and beyond human hearing, some social calls and sounds made within their roosts are audible to humans. Bats can also produce a rapid series of clicks, known as a “feeding buzz,” when zeroing in on an insect.
Shrews, tiny insectivorous mammals, are quite vocal and produce a diverse range of sounds. They communicate with squeaks, chirps, and clicks. Many of their high-pitched sounds are outside the human hearing range. These animals often make constant “twittering” noises as they move through grass and undergrowth, with volume increasing when other animals are present. They may also emit louder alarm squeaks when threatened.
Young or distressed larger mammals can also produce squeaking or high-pitched sounds. Baby raccoons, for example, cry and squeal, especially when hungry or separated from their mothers. These sounds, sometimes described as similar to a “chirping bird,” can be quite loud and are used to get their mother’s attention. Young raccoons in their den may also let out loud squeals if they feel pain or perceive a threat. Baby opossums, known as joeys, primarily make a “sneezing” sound (“CHH! CHH!”) to get their mother’s attention. A distressed or injured baby opossum might also make quiet whimpering sounds.
Avian and Insect Chirps
Nocturnal birds and insects can also produce sounds that resemble squeaks or high-pitched chirps. Certain bird species, such as nightjars, are known for their distinctive calls at night. The Eurasian Nightjar produces a “churring” call. The Large-tailed Nightjar makes a monotonous series of hollow “chonk, chonk, chonk” notes, which can sound like chopping wood, along with frog-like croaking and soft growls. The Australian Owlet-nightjar makes a variety of sounds, including churring notes, soft “tyeow” calls, and higher-pitched shrieks and squeaks. While some owls may hoot, other species or young birds in nests might produce chirps or squeaks as calls for their parents.
In the insect world, crickets are a prominent source of nocturnal chirping. Male crickets produce these sounds by rubbing their wings together, a process known as stridulation. This chirping serves to attract female mates and warn other males away from their territory. Crickets are most active at night because darkness offers protection from predators, and the quieter environment allows their chirping to travel further. The frequency of their chirping can increase with higher temperatures.
Interpreting Nocturnal Squeaks
Understanding the context of nocturnal squeaks involves considering factors like volume, frequency, and location. These sounds often signify communication among animals, whether it is an alarm, a territorial warning, a mating call, or a distress signal. For instance, a continuous series of squeaks from within walls might suggest rodent activity, particularly if accompanied by scurrying or scratching.
A sharp, isolated squeak could indicate a sudden fright or pain in a small mammal. The specific pitch and repetition of the sound can offer clues about the animal’s emotional state or intent.
Observing accompanying noises, such as gnawing, scratching, or rustling, can further help identify the source. A rhythmic, repetitive sound from outdoors might point to an insect like a cricket, especially if consistent in pattern. By paying attention to these auditory details and any other environmental cues, one can better discern which creature is responsible for the sounds heard in the night.