Well don't think I'm a birdwatcher, but my girlfriend started to have some interest in birds since our trip to New Zealand last year. So I think I did pick-up some knowledge here and there 😅

What mount are you looking at? Maybe it is more wise to invest already in that mount and try to help yourself out on your current mount with a adapter? Otherwise you where shooting Nikon right? When you switch to their mirrorless camera's they have the FTZ adapter added when you buy a body. That way I would advise a 200-500 from Nikon. that lens works great with the FTZ adapter. But the 60-600 from Sigma is also a great object to buy. Only not sure how that one works on the Z mount from Nikon. So that would be something you have to try for yourself.

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