I loved the monkey's when I visited the Werribee Zoo, because they were a fair distance away I needed to use a lens with a longer focal length which is where my Tamron 15-600mm lense came in. At the longer focal lengths there is a much greater chance of motion blur when the lens is handheld. So, excluding any requirements for the monkeys, the shutter speed needed to be at least 1/focal length (e.g. 1/600). If the monkey's were moving quickly then it needed to be faster again.
As with all of my images, I use Nikon gear. This is not because I think Nikon is better than Canon but just because it is what I got started with and wanted to maintain lens compatibility. The images were captured / edited with the following gear;