We love watching fast moving wildlife and our typcial image involves freezing their motion with our cameras to produce detail that our eyes cannot see while the animal is in motion. Capturing a diverse set of images is always a challenge for any photographer and adding motion to an image provides the viewer with a feeling of movement as they stare into a still image.
To add motion and a feeling of wildlifes speed, try experimenting with diffent shutter speeds to produce the amount of motion you desire in your images.
I like to photograph Bald Eagles (some friends say its a bit of an addiction) and typically prefer shutter speeds of 1/1,250 second to 1/1,600 second to freeze the eagles wings and talons. When the light is low, it is fun to experiment with different settings to produce a different look and feel.
Here are some examples:
As you can see, experimenting with a wide range of shutter speeds produces drastically different results. Those days where the light is lower than optimal is a great time to practice and learn which style is your favorite. Get out there and enjoy wildlife photography.