how do they communicate?
Communication among them is accomplished mainly by olfactory and auditory signals. Scent marking is imperative for intergroup communication.
North American river otter
Communication among North American river otters is accomplished mainly by olfactory and auditory signals. Scent marking is imperative for intergroup communication. The North American river otter scent-marks with feces, urine, and possibly anal sac secretions. Musk from the scent glands may also be secreted when otters are frightened or angry.

North American river otters can produce a snarling growl or hissing bark when bothered, and a shrill whistle when in pain. When at play or traveling, they sometimes give off low, purring grunts. The alarm call, given when shocked or distressed by potential danger, is an explosive snort, made by expelling air through the nostrils. North American river otters also may use a birdlike chirp for communication over longer distances, but the most common sound heard among a group of otters is low-frequency chuckling.
where do river otters live in the winter They travel drastically less during winter. is this creature a mammal, reptile, amphibian, or any other? Mammal how long can this creature live underwater? 4 minutes do they have a special respiratory system or any other metabolic adaptations to survive underwater for so long? The right lung of the North American river otter is larger than the left, having four lobes compared with two for the left. Reduced lobulation of the lungs is presumed to be adaptive for underwater swimming. In addition, the length of the trachea of the North American river otter is intermediate between that of terrestrial carnivores and marine mammals. The mean tracheal length of the North American river otter is , or 23.2% of the body length. A shorter trachea may improve air exchange and increase lung ventilation in diving mammals.
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North American river otter [SEP] Communication
Communication among North American river otters is accomplished mainly by olfactory and auditory signals. Scent marking is imperative for intergroup communication. The North American river otter scent-marks with feces, urine, and possibly anal sac secretions. Musk from the scent glands may also be secreted when otters are frightened or angry. North American river otters can produce a snarling growl or hissing bark when bothered, and a shrill whistle when in pain. When at play or traveling, they sometimes give off low, purring grunts. The alarm call, given when shocked or distressed by potential danger, is an explosive snort, made by expelling air through the nostrils.