Ultimately, the fishermen decided it was a risk they had to take. These cubs belonged to their mother, and they had a duty to reunite the family. In all the excitement of rescuing the cubs, the mother had disappeared from view.
Fortunately, one of the fishermen had been keeping an eye on her, and knew she'd made it onto the island. Strangely, though, there was no sign of her now. Was she still on the island somewhere? If she wasn't, what on Earth were they going to do with these cubs?