Nutria

Myocastor coypus, commonly known as the nutria or coypu, is a large, semi-aquatic, herbivorous rodent native to South America, introduced to North America. Adults typically weigh 4-10 kg and measure 70-100 cm in total length, including a long, round, scaly tail. They possess coarse brown fur, prominent white whiskers, webbed hind feet, and bright orange incisors, which grow continually. Nutria are primarily crepuscular and nocturnal. They are highly prolific breeders, capable of year-round reproduction in warm climates, producing 1-3 litters annually of 2-13 young (average 4-5) after a gestation of 130 days. Young are precocial. Lifespan is 1-3 years in the wild.

Nutria are voracious herbivores, consuming up to 25% of their body weight daily in various aquatic and terrestrial vegetation. Their diet includes roots, rhizomes, tubers, and shoots of wetland plants, as well as agricultural crops. They cause extensive damage to wetlands by converting vegetated areas into open water through destructive foraging, known as 'eat-outs.' Nutria are highly adept swimmers and divers. They construct burrows in banks, contributing to erosion and undermining infrastructure. They are generally shy but can be aggressive when cornered. Their burrowing can destabilize levees, dikes, roads, and bridge abutments, leading to significant structural damage.