* Orcas (Killer Whales): Orcas are apex predators known to prey on a variety of marine mammals, including large animals like whales. It's likely that Steller's sea cows would have been vulnerable to orcas, especially calves or injured individuals.
* Polar Bears: While Steller's sea cows were primarily found in the North Pacific, polar bears do have a range that overlaps with their former habitat. Though polar bears are primarily land-based hunters, they are known to be opportunistic and might have preyed on Steller's sea cows if the opportunity arose.
* Great White Sharks: Great white sharks are also apex predators and have a large range that could have included some of the areas inhabited by Steller's sea cows. They could have posed a threat to sea cows, especially if they were injured or weakened.
It's important to note that while these animals could have been potential predators, there's no concrete evidence that they actually preyed on Steller's sea cows. The most significant threat to their survival, as mentioned, was overhunting by humans.