Nannopterum brasilianum, commonly known as the Neotropic Cormorant, is native to the Americas. Its geographical distribution includes parts of North, Central, and South America. The species is found from the southern United States, down through Mexico and Central America, and throughout much of South America, reaching as far south as Tierra del Fuego in Argentina and Chile.

The Neotropic Cormorant typically inhabits freshwater and coastal environments. It is commonly found in lakes, rivers, mangroves, marshes, and estuaries. The species tends to prefer warm climates with abundant water bodies, although it can adapt to a range of wetland habitats across its distribution range.

Nannopterum brasilianum primarily feeds on fish, which it captures by diving. The species is well adapted to its aquatic environment, possessing powerful webbed feet for swimming and a streamlined body for efficient diving. It exhibits versatility in its feeding strategies, sometimes working cooperatively in groups to herd fish into shallower waters. Additionally, the Neotropic Cormorant uses perches and tall vegetation around water bodies for nesting and roosting, which also serve as vantage points for scanning the waters for prey.