What would be a good DSLR lens for a safari?

I'm hoping to be going on a safari in a year to africa and i was thinking of getting a new lens for it. I have a Nikon D3000 DSLR camera and the only lens I have is the basic one that came with it. I don't want to get a like super- telescopic lens, because from the photos i've seen, the animals are pretty close, but I think i might need a little more zoom than i have now. Any suggestions?

A 70-300. Will augment the kit lens nicely.
You only need to use as much zoom as you need.

I'm with Paul R. On this one. Normally, I'd recommend getting the longest zoom you can afford for a safari, but if you're pretty sure that you won't be that far, then the Nikon 70-300mm AF-S VR is your best bet. The VR (vibration reduction) will be a life saver, especially if you don't have a tripod or the vehicle you're in is moving. The new Nikon 55-300mm AF-S VR is less expensive, but doesn't focus as fast, so you may miss some precious shots.

The 70-300mm (i think there's also a 55-300, you can also pick up 50-500mm, but that is a super telephoto) this range is a good step up from the kit lens. Good luck with your final choice and have fun on the safari.

Go for Sigma APO 150-500mm DG OS HSM.

It is very sharp for its price and focal length range, has optical stabilization and very good while panning on moving animals.