According to Wikipedia:
Great Blue Herons can be found in a range of habitats, in fresh and saltwater marshes, mangrove swamps, flooded meadows, lake edges, or shorelines, but they always live near bodies of water. Generally, they nest in trees or bushes that stand near a body of water. In general, what is shared in common is that all must be near or on a site of water for a living area (nest.)
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