I'm not a bird photog, but I am a veteran of many beach pictures, which also have issues around weird artifacts, water and sunlight reflections. In short, there are so many things that can go wrong with water, waves and light that it's just better to deal with them with software. Refractions, reflections, optical interference, weird lense-like transparency effects, small floating objects and even bubbles can create chaotic light that you can't realistically anticipate, especially when you're also trying to catch a good bird shot. Just edit them out if they're bad or make a lot of shots and find the one with the least chaos.