Arizona is situated in the southwestern United States. As the sixth largest state, it possesses diverse geography – the deserts are hot and dry, whereas the Colorado Plateau in the northeast is cooler overall, with cold winters and mild summers.
Just one species of otter can be found in Arizona: the southwestern river otter, which is a subspecies of the North American river otter (Lontra canadensis).
1) Southwestern river otter (Lontra canadensis sonora)
- Native to rivers and basins of southwestern North America
- Family: Mustelidae
- Order: Carnivora
- Conservation status: Least concern
Also known as the Arizona river otter, Lontra canadensis sonora grows to lengths of around 90 cm (3 ft) and may weigh up to 9 kg (20 pounds). This species is characterized by its webbed feet, long, tapered tail, and short, glossy fur. River otters have evolved for both aquatic and terrestrial movement – individuals have short legs, muscular necks, and elongated bodies.
The history of the southwestern river otter in Arizona is complex. In the 1960s this species became extinct in the wild, but then between 1981 and 1983, a reintroduction program was begun. Forty-six individuals were released into the Verde River, and while the population is now thriving, changes to the use of the river may threaten these otters again.
Although the IUCN has designated this species as that of least concern, this is an assessment of the North American river otter as a whole, thus it does not consider the statuses of subspecies. Other sources suggest that Lontra canadensis sonora may be critically imperiled. Threats include development, agriculture, trapping, changes to water management, pollution, and climate change.
The southwestern river otter is a playful species, spending much of its time leaping in and out of the water and splashing. This behavior is thought to help maintain social bonds. These otters feed predominantly on fish and crustaceans – it is thought that the habitat type may influence which prey an individual pursues.
