Got a Cannon Rebel camera and would like to know what lens I should get to...

[massmama]

you need a telephoto lens...stick with canon rather than sigma

 

[Ken E]

...photograph wildlife? Birds,deer,bear from afar and get a extreme closeup shot

 

[Fishmeister]

It's difficult to say without you giving us a budget.

I want to say the 300mm f/2.8 L IS....

http://the-digital-picture.com/Reviews/Canon-EF-300mm-f-2.8-L-IS-USM-Lens-Review.aspx

But you had better have deep pockets..

Canons 400mm L f/5.6 is a great lens for wildlife and is a respectable price..

http://the-digital-picture.com/Reviews/Canon-EF-400mm-f-5.6-L-USM-Lens-Review.aspx

If you can get used to the push/pull zooms then look at the 100-400mm f/4.5-5.6..

http://the-digital-picture.com/Reviews/Canon-EF-100-400mm-f-4.5-5.6-L-IS-USM-Lens-Review.aspx

I personally could not get used to it and handed it back to my friend after less than hour. You on the other hand may like it..

Try giving us a budget and then it will be easier to give a good recommendation.

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