The environmental image tends to be more of a story teller as it denotes a sense of place. The head shot is powerful as it provides an up close and personal look at the species. Both have their place in wildlife photography and I strongly encourage you to capture both options. Regardless of the one you choose, adhere to the compositional rule of thirds.

For the head shot, the eyes should fall into the top third of the frame. For the environmental image, position key elements into the power points that constitute the position of a third to create balance and intrigue in your compositions.