When in doubt, get closer. Many beginning nature photographers are amazed when they see their first wildlife photo's. The animal they found, and stalked and photographed are small dots on the film, barely recognizable. Secondly, keep in mind that when you take a picture, you're reducing the image when you photograph it. That's not at all like the photo's you've seen in magazines.
Proximity is what impresses the viewer.
Part patience, part technique. But a 200 mm. But for smaller wildlife, a 200 mm. It may be a tent, a bush, a wall of camouflage material, a car, or even a window. The point is, the photographer lets the wildlife come in close to him or her.