Here's a neat tip I recently picked up from a YouTube video. When shooting a subject against a bright background (e.g. shooting birds against a sky), move the exposure compensation on the camera up about a stop (or even more, if necessary). The photo below of a red-tailed hawk was shot with +1 exposure compensation, and it didn't take much tweaking in Lightroom to get a nice looking image. You can click the image to get a larger view of it.

Prior to learning this tip, I've ended up with a ton of disappointing birds in flight photos. No more!