what is their gestation period?
61–63 days.
North American river otter
Female estrus lasts about a month per year, and true gestation lasts 61–63 days.
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. how do they communicate? Communication among them is accomplished mainly by olfactory and auditory signals. Scent marking is imperative for intergroup communication. at what age do females start reproducing? Females usually do not reproduce until two years of age. how many pups do they give birth to? Litter size can reach five, but usually ranges from one to three.
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North American river otter [SEP] Reproduction and life cycle
North American river otters are polygynous. Females usually do not reproduce until two years of age, although yearlings produce offspring on occasion. Males are sexually mature at two years of age. The number of corpora lutea increases directly with age. North American river otters typically breed from December to April. Copulation lasts from 16–73 minutes and may occur in water or on land. During the breeding, the male grabs the female by the neck with his teeth. Copulation is vigorous, and is interrupted by periods of rest. Females may caterwaul during or shortly after mating. Female estrus lasts about a month per year, and true gestation lasts 61–63 days.