A couple from my first successful outing with the 1D X + 300 f/2.8 IS II & 1.4x III:Mack, it looks like you and the 1Dx are becoming fast friends! Great images! I love the detail and sharpness in #2 and Excellent composition in the third, love the log, the colors and the separation from the background, exceptional shot!
Snowy Egret @ 420mm f/4 1/500s ISO 400:
Anhinga @ 420mm f/4 1/1000s ISO 4000:
Double-crested Cormorant @ 300mm f/2.8 1/1250s ISO 320: