Bird photography tips
Patience is the key.
If you want to shoot a bird you need a lot of patience waiting for it to sit in the right place or slowly move towards him. If you got a chance to be close to it you can definitely use a portrait lens 50-85mm for full-frame or 30-55mm for the cropped sensor.
The higher parts of this range will allow you to have some distance of 2-3 m from the subject. With a Sigma lens 85mm f/1.4 you achieve a perfect bokeh which gives you this nice portrait feeling.
It’s not always easy to get close to the bird. Many times not even possible. That’s why you should have telephoto lenses in your inventory.
You can even be a hundred meters far from the target and still have a good close-up.