Perfect For Use In A Bird Hide!
A straight bodied scope like the Opticron IS 70 R is a great choice if most of your birdwatching is done from the comfort of a bird hide. The scope can be easily mounted on an optional hide clamp or other universal mount and the "straight through" view means you can switch from using just your eyes (or binoculars) to locate the bird you are interested in, to then use the scope to see more detail.
For critical ID or for reading leg rings, the higher end of the 20-60x zoom range will pull out the fine details. The 70mm objective lens delivers plenty of light - more than 35% more light than a 60mm scope - extending the amount of time you can use the scope at the beginning and end of the day.