One of the basic points I am trying to get across is that the exercise of an instinct requires a great deal of thinking on the animal's part. Instinct is basically an alternative to learning, which means the critter knows something, or how to do something, without first learning it. The animal is born an expert, as it were.
But actually implementing that knowledge in a specific situation requires a lot of thought, just as it does with learned expertise in humans. So simply saying that an animal does what it does by instinct is missing an important question, namely what is the animal thinking? Interestingly there is a lot of research on how humans apply expertise, which may be useful in understanding how animals apply instincts.
Nor is understanding a specific instinct easy. Here the key question is what does the animal have to know (or believe) in order to do what it does? Merely saying it is instinctive is not helpful.