I have done something like that in Alaska 13 years ago.
I had a Canon SLR 35 mm film camera with a Tamron 28-300 (f3.5-5.6) mm plus UV and a polarising filter.
Appart from rafting, where I had to leave my camera on the river bank for obvious reasons, I didn't feel that I needed any other lens.
You have to decide if it's going to be a trip with great pictures opportunities or a wildlife photography expedition that needs you to gear up more seriously.
Of course it would had been nice to have a big 400 mm lens with me for that distant eagle or fishing bear, but to carry that one for hours and to change in haste the lens only to find that the bear or the eagle are gone seemed pointless. I did feel the need for a wider angle lens for those huge landscapes and it wouldn't be bad to have one handy. But most of the time 28 mm was good enough.
I had a german tripod 30 cm long when folded but seldom used it.
Hope that helps
Oh, I almost forgot the most important item, you must have some moskito repelant with you, that one will greatly improve your images

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Radu
Canon PowerShot S100
Canon 50D , SIGMA 10-20 f3.5 ,Canon EF 24-105 L IS USM, Canon EF 100/2.8 macro Canon EF 50/1.4 ,Canon EF 85 f1.8,Canon EF-S17-85 4-5.6 Old Tamron 28-300 inherited from my Canon Rebel G film camera
Canon580EXII
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