the problem would be the highlighted sentence, the solution would be "They're considering using a type of gene-editing tool known as a gene drive"
This is because the start of the passage explains that these birds are going extinct because of a mistake they made before, they don't want to make a mistake again, so they offer a well thought out plan, which is to use a type of gene editing tool known as a gene drive.
It means, for example if I say, "I go to the park every now and then", then it isn't a common event, but happens often enough not to be classified as a rarity.
