Glossy Ibises nest in colonies, often among other species of ibis, heron, egret, or spoonbill. Colonial nesters have the advantage of many extra sets of eyes looking out for predators. Colonies might also be places where highly gregarious species like ibises can share information about the most productive foraging areas.
I wasn't aware the Glossy Ibis existed until I saw one that I thought was an immature White Ibis until I got close enough to realize I was mistaken. The Glossy Ibis is commonly found in shallow freshwater wetlands, as well as brackish and saltwater wetlands, mangroves, and rice fields. Over much of its range, Glossy Ibises can be seasonal or very local, look for a tall bird foraging slowly in open wetlands or flying with neck and feet outstretched.