Study data sheets of all posted models and make a table/sheet with all features for your use case (watching birds). When this would be my use case, I would look for this:
DS-2CD7A85G0-IZHS
Image Sensor: 1/1.8"
Minimum Illumination Color: 0.007 lux @ (f/1.2, AGC on)
FOV: 2.8 to 12 mm, horizontal...