There is a very wavy line between the benefits of "recce"ing a site without a camera or doing the same thing with one.
There is always a temptation, especially on a new site and, if on a trip with a limited amount of time available, to leap out of the transport and "get stuck in". In view of the frequent spontaneity of Wildlife Photography this is almost a commendable behaviour pattern. However the problem is that, particularly if you have a specific target, you tend to get bogged down with the first specimen you come across for fear of missing what might be your only chance. I, personally and weak willed as I am, find it very difficult to walk on by potential subject matter when carrying a camera. As a result of this I often survey a new site, particularly if it is a botanical one, with my camera firmly in its bag back in the vehicle. The disadvantage of this is that you will occasionally miss opportunities that may not re-present themselves but the upside is that it gives you the chance to decide what the site has best to offer. If you fall to your knees in front of the first specimen that you come across then, particularly with time constraints, you run the risk of not seeing and capturing that marvellous bunch/flock/herd/group or mating pair just around the corner that you didn't have time to turn. Of course many of the more spectacular wildlife shots are taken on spur of the moment encounters and there is always that chance of missing one of these.
Hey - they do say that life's a compromise and photography is no different!