Recommend a lens

[Progenix Oj101]

Another alternative might be to rent the lens if your trip is not going to be too long. A 150-600 costs R336 per day from ODP. If you are worried about the light or just want to indulge the Canon 400 F2.8 prime is available at R600 per day, as is the 600mm F4.

That Canon is a great option, probably greater than the 150-600. I've seen it compared to 150-500 lenses with the image cropped to the same effective focal length, and it resolves far more detail - enough to be sharper even when cropped.

 

[eternaloptimist]

Disregard the 150-600mm options for now - be it Tamron or Sigma.
The 18-55 EFS will be ok for landscapes but look at the 50mm Nifty Fifty / Fantastic Plastic at about R 1000 or so. Just get one anyway , you will not regret it.
Longer lens on a budget ? Canon EF 70-300 USM Mk II , gives up to 480mm on the crop sensor . Shoot 800 ISO F8 and AV. Cheap as used kit . That fills the Camera bag nicely and is not heavy or large to travel with.
Even a 120-400 Siggy is a lot to carry around.

Thanks, I have those lenses already so might just bring them with me.

Thanks everyone for the recommendations!