You will need both long and short lenses as, depending on where you are going, animals come right up to the vehicles and so something like a 17-50/2.8 is going to be one you need.

For long you need really long and the 55-300 is soft at 300 and too slow (as often animals are most active early morning/dawn and late afternoon/dusk) also you are better shooting at 250 where the 55-300 is sharp and cropping to a 300 FoV.

Something like the Tamron 17-50/2.8 and then the Pentax DA*300/4 (plus the AFA x1.7 TC would be a must in my book) would be a lightish and small kit to cover most eventualities. All can easily be sold on your return if required.

It's very cool idea and I can see endless possibilities.

Very sweet shots and bird. They are a bit similar in size, looks and behaviour to our Eastern Crowned and Arctic Warblers. Tiny, though the warblers are confiding.

Yesterday I had an Eastern foraging around at my feet not 3 feet away ... whilst the 500mm was pointing away into the distance (I also had a cuckoo land 6 yds in front of me - whilst the camera was on a monopod slung over my shoulder - drat) !

Excellent shots Don ! Love the first, the second looks slightly over-exposed to me (bring the colours back to those of #1 and I'll be happy again)

Ugly bird, huge beak, excellent shot !

Lovely shots of a lovely bird.

Do you use a hide ? Camo clothing ? Get down and dirty ?

Very good to hear. Well done to Paula & Ian.

Whatever I wrote before I've changed my mind. The Zeiss SF2 35/2.0 I bought recently is absolutely insanely sharp but produces glorious colour rendition too.

A really lovely series, #4 & 6 are my favourites.

I'm not sure that the ND Grad is not spoiling one or two of those shots - #2 is the strongest example with the top of the frame darkened to such an extent that it is almost compressing the shot into less space and is an obvious darkened line across the top of the frame. Maybe a polariser would do a better job ?

So do I - and #1 is superb.