This is a general guide to photographing water birds. It’s not aimed to provide specific guidance on shooting bird photography in a particular country or environment. Water birds tend to have similar mannerisms everywhere. You can take this as a general introduction if you’re interested in photographing them.
Shoot with a telelens
Don’t worry about wide apertures and bokeh and such things. Get yourself the fastest and longest focal length you can lay your hands on and shoot with that. When there is a considerable distance between you and the subject and the subject and background, even an f/5.6 lens can produce a decent background blur.
The quality of the blur (i.e., bokeh) will, however, depend on the number and shape of the lens’ aperture blades. If the number of blades is eight or more and the blades are rounded instead of straight, the bokeh quality will be better.
However, the most significant advantage of using a telelens is that it allows you to get very close to your subject without disturbing it.
More frames per second are better
When it comes to shooting water birds, more frames means higher chances of capturing at least a few frames where everything is sharp. This is true for any wildlife photography assignments.
Choose a camera with a high frame rate or continuous shooting speed. Among entry-level DSLRs, the Nikon D500 is a great camera, offering ten fps continuous shooting speed. But these days, mirrorless cameras have taken over, and among Nikon mirrorless units, the Z7 II is a great camera to boot. But consider the price difference because the Z7 II is significantly more expensive than the D500. The Canon EOS R6 Mark II is a decent choice among Canon cameras with its 12 fps mechanical shutter. A budget option is the Canon EOS R7 with its 15 fps continuous shooting with a mechanical shutter.
When it comes to wildlife and birding, you can’t have a fast continuous shooting speed. It would be best if you also had a decent buffer to exploit that continuous frame rate. If the camera starts to slow down only after a few seconds of continuous shooting, you will never be able to make enough images. As often happens in wildlife photography, only one in a series of shots turns out to be perfect from all parameters. Those extra frames count, and a deeper buffer makes a big difference.
Autofocusing and subject tracking