Originally posted by Wolfestone better option for taking wildlife photos
"Wildlife" can mean different things: small birds in the back yard, birds in flight, squirrels in the park, deer in the forest, elk or sheep at extreme distance and so on.
I have owned and sold two different mirror lenses and was not happy with either. They are manual focus and extremely fussy, I failed to get any images I liked using them.
When you say 'zoom' lens do you mean an actual zoom lens such as the DFA 150-450 or a 'telephoto' such as the DA 560mm or DA*300mm. Both are excellent lenses but have different characteristics.
You do not mention budget and when you start talking long lenses that has to be a consideration. Wildlife enthusiasts will use 600mm f/4 lenses that cost a fortune. Short of that there are options such as the DA*300 or the DA 560mm. A good compromise is the DA*60-250 which I highly recommend. If budget is a restriction look at several of the older Pentax zooms like the FA 80-320, it is slow but in good light will work and the cost much lower. The various versions of the DA 55-300 are also highly recommended.