Here's why:
* Nurse sharks are bottom dwellers: They spend most of their time on the seafloor, while killer whales are more pelagic (open ocean) hunters. Their habitats don't often overlap.
* Size and defense: Adult nurse sharks can reach up to 10 feet in length and have strong jaws, making them a tough target for a killer whale.
* Killer whale diet: Killer whales are known to eat a wide range of prey, including fish, seals, sea lions, dolphins, and even other whales. They tend to focus on prey that are abundant and accessible in their habitats.
It's possible that a killer whale might opportunistically take a nurse shark if the situation arose, but it's not considered a regular part of their diet.