With patience and good planning I consider the Great Blue Heron a moderate to easy bird to photograph. What is odd to me is at some times of the year I can not approach the Great Blue without it taking flight while other times the bird mostly ignores me. This behavior might be related to feeding and mating because most of my success is in the Spring to Summer months and as fall approaches the Great Blue Heron seems more skiddish.
Here are my tips to acquiring great photos of the Great Blue Heron.
Early morning, late afternoon or on light overcast days that cast soft shadows are the best times. Try to determine an area these birds visit and determine the best shooting location (sun behind you lighting the bird).
These are tide birds, meaning they depend on about 2 foot of water, not too deep, not too shallow. I normally have better luck in tidal marsh areas during low tides as the food source becomes more easily plucked from the water.
In the left Great Blue standing shot the sun is in front of me and behind the Great Blue - not good - however, due to the early morning hour, I was able to pull it off with a good exposure. In the photo to the right (Great Blue Flying) I was just about ready to stop for the day because the light was getting bright and harsh, then this Great Blue Hero flew in, right across my path, my esposure was already good, bam! Point is - arriving early and staying a little later can reap rewards.
Get into position early and wait it out. If your lucky you will have an opportunity for a bird in flight photo as they fly into the marsh. I normally set up close to a bush or tree in the shade to help conceal my outline and equipment and will normally wear drab camo shirt and pants and try not to move much while I am waiting.
While waiting I take a couple test shots for exposure, and try to always shot manual mode. Nothing can be more true than knowing and trusting your own experience. Sometimes your meter simply is not giving you the best exposure. If your really want a near perfect exposure get yourself a Sekonic spot meter. My rule of thumb is "histogram" and error on side of under exposure because you can never recover the details in your blown out highlights. for non bird in flight shots, I use the lowest ISO I can muster based on the lens length and VR capabilities.
Once the Great Blue finds the location and lands, be steady and make slow movements while you get a few great shots, checking the histogram for the first few and make adjustments then keep at it. If the Great Blue is in feeding mode, it will traverse an area back and forth slowly then striking the food item. With practice you can almost determine when the bird is ready to strike and get the action photo.
What Equipment to use: I have no right answer. I been in situations where a 400mm was too long because the bird was ignoring me and close to the shore where I was shooting, but at other times a 600 with a 17 TC was barely long enough. In the right lighting a Great Blue "environment" photo is a better photo than a tightly cropped bird only photo - Lens technology today has brought very good quality long zooms within reach to most people at an affordable price and I would certainly consider and recommend one for your bird photography, something in the 200-500 zoom range.
The Great Blue Heron is a wonderful bird to photograph and is one of my favorites.