For bird photography on the Z system, you really can't go wrong with the Z 400mm f/2.8 TC VR S if budget isn't a concern - it's absolutely stellar with incredible sharpness and the built-in teleconverter gives you 560mm when needed. But realistically, most of us are looking at the Z 100-400mm f/4.5-5.6 VR S, which is fantastic for the price point. Great reach, solid image quality, and much more manageable than the big primes. I've been using it for over a year and consistently get sharp shots of everything from songbirds to raptors.

Nikon Z 400mm f/4.5 VR S.

I totally agree with the sentiment that finding a lighter, more manageable setup is the real game changer for birding. Before I fully committed to my current kit, I spent a lot of time doing market research on how Nikon’s roadmap compares to other brands. I was tempted by some of the third-party zoom options on other systems, but I’ve always been a bit cautious about long-term reliability and focus speed. So basically, here is what I found during my research:

• Native glass consistently outperforms third-party options for tracking fast birds.
• The resale value of the high-end native lenses is way more stable than the alternatives.
• Total weight is the biggest factor in whether you actually take the gear out of the bag. Honestly, I learned that the hard way. I used to use a really heavy setup and after an hour at the local wetlands, my technique would just fall apart. I switched to the compact one I have now and my keeper rate skyrocketed because I can actually hold it steady. Idk if I could ever go back to those massive setups. It’s just not worth the strain for me.

Honestly, I am in the exact same boat with my Z8 right now and it has been a total headache trying to decide on glass. I had high hopes for my old setup but unfortunately the transition to mirrorless has been way more expensive and frustrating than I anticipated. I actually tried to DIY a mount repair on my old backup lens last week after a trip to the coast... total disaster.

• the tiny screw heads stripped almost immediately
• found way more salt corrosion than I expected
• spent three hours with a magnifying glass just to lose a spring It actually reminds me of when I tried to refurbish my old wooden tripod legs myself. I thought I could just sand them down and refinish them in the garage, but I ended up using the wrong type of sealant and the whole thing stayed sticky for a month. I got so annoyed that I ended up spending the weekend reorganizing my entire workbench and sharpening all my wood chisels instead of actually shooting. My garage is spotless now but I still dont have a working long lens for the weekend. Anyway lol, sorry kinda went off topic there.

I'll throw in a different perspective - don't overlook the Z 70-200mm f/2.8 VR S with teleconverters. With the 2x TC you get 400mm f/5.6, which is still very usable, and you have the flexibility of the zoom range without the TC for closer subjects or environmental shots. The 70-200 is also incredibly sharp and the faster aperture helps in low light situations like early morning shoots.

Saved for later, ty!