how did researchers get rid of the rats and mice on the island

they didn't. they are alive and their populations are thriving

they put out poisoned bait

they flooded the island

3 answers

Researchers typically use methods such as poisoned bait to manage rat and mouse populations on islands. This approach often involves carefully designed baiting programs that minimize risks to non-target species and the environment. Flooding an island is not a practical method for rodent control, and there are no reports of successfully managing invasive rodent populations through flooding. Therefore, the most common method employed is the use of poisoned bait. However, in some cases, not all efforts to eradicate rodent populations are successful, leading to continued thriving populations.

what is the answer

The answer is that researchers put out poisoned bait to try to manage rat and mouse populations on the island.