Sireniën

Sireniën are the order Sirenia, a small group of large, fully aquatic, herbivorous mammals that includes the extant families Trichechidae (manatees) and Dugongidae (dugongs). The Dutch term sireniën corresponds to this order and in English they are commonly called sirenians or sea cows. The name stems from the Sirens of Greek mythology, reflecting early beliefs about their songs. The order also includes the extinct Steller’s sea cow (Hydrodamalis gigas), once found in the North Pacific.

Sirenians are streamlined, slow-moving creatures with paddle-like forelimbs and a broad, horizontally oriented tail. They lack dorsal fins and external ears. They breathe air through nostrils on the upper snout and must surface regularly. Teeth are adapted for a herbivorous diet of seagrasses and aquatic vegetation; manatees have molars that are replaced as they wear, while dugongs can develop tusk-like canines in some individuals. They inhabit shallow, coastal waters, rivers and estuaries in tropical and subtropical regions, often in seagrass beds which form the basis of their diet. They are typically solitary or found in small, loose groups and have slow reproductive rates, with gestation around 12 months and extended lactation.

Conservation: All living species face threats from habitat loss, boat strikes, entanglement in fishing gear, and hunting. IUCN assessments generally classify most sirenian species as Vulnerable, with some populations listed as Endangered. Protection of seagrass habitats, boat-speed regulations, and rescue and rehabilitation programs contribute to their ongoing conservation. Sirenians have long lifespans, with individuals living for several decades in the wild.