Sirenia – Sirenians
Cows who decided to dive deep
The remarkable tale of sirenians, or sea cows, is one deeply intertwined with the history of human exploration and exploitation. In the year 1768, a mere 27 years subsequent to their European discovery, the gentle giant known as Steller’s sea cow, a member of the family Dugongidae, found itself on a sorrowful path to extinction. This behemoth of the sea, which once glided through the kelp-rich waters of the North Pacific, was relentlessly hunted for its substantial meat and fat reserves, leading to its tragic demise.
The contemporary relatives of Steller’s sea cow, which include species like the manatee and the dugong, continue to traverse the warmer waters of our oceans. These modern-day sirenians, characterized by their languid movement and protracted reproductive cycles, find themselves facing mounting threats from human activity and environmental changes.
These fully aquatic mammals, which can trace their lineage back to a time when their ancestors walked on land or dabbled in the shallows, have since been fully enveloped by the aquatic realm. Yet, they retain the quintessential trait of surfacing for air, a gentle reminder of their terrestrial heritage. This regular ascent for breath punctuates their otherwise submerged existence and is a sight that has enchanted seafarers for centuries.
These creatures, with their rotund forms stretching 2.5 to 4 meters in length, depending on the species, echo the bucolic presence of a bovine on the waterbeds. Their bodies, though adapted to the liquid medium, still bear semblance to the terrestrial cows, a nod to their evolutionary past. However, the comparison extends beyond mere physicality. These gentle beings dedicate a substantial portion of their waking hours—about eight each day—to foraging for sea grasses and other aquatic plants, much like a cow grazing in a meadow.
Sirenians are known for their peaceful demeanor and slow-paced lifestyle, which, unfortunately, contribute to their vulnerability. Their leisurely reproductive rate, with females typically giving birth to a single calf every few years, coupled with the pressures from habitat destruction, boat collisions, and entanglement in fishing gear, compounds the risk of their populations dwindling.
Families in this order
Freshwater herbivores inhabit the shallow marshes and rivers of coastal areas
The marine (salt water) fluke-tailed cousins of the freshwater manatees