Here’s the complete code that appears in that page/post:
<div class="wp-caption aligncenter" style="width: 650px" id="attachment_412"><a href="http://www.beyondthechickencoop.com/wp-content/uploads/2015/02/Chopped-Chicken-Salad.jpg"><img width="640" height="480" alt="Oriental Chopped Chicken Salad" src="http://www.beyondthechickencoop.com/wp-content/uploads/2015/02/Chopped-Chicken-Salad.jpg" class="size-full wp-image-412"></a><p class="wp-caption-text">Oriental Chopped Chicken Salad</p></div>
Removing style="width: 650px" should be good enough.
In responsive design you want to avoid setting fixed pixel widths.