Will Guineas eat rats if I don't have a huge flock of them? I only have room for 2
If you only have room for 2 guineas, I recommend that you don't get any guineas. They are a flock bird and do best in large groups. I recommend a minimum of 10 guineas.
Guineas will kill and eat small animals such as mice, voles, lizards, etc. Rats are not that small. While a flock of guineas may drive away rats during the daylight hours it is highly unlikely that a pair of guineas or even a flock of guineas would have any effect on rats during the night.