What are they?

In Cheongna, I found many birds flying around. I saw birds staying in the place where the bulldozer mowed down all the reeds so that there can be some kind of construction going on. The whole area looks desolate, with rotting reeds and some mud puddles left due to rain. However, there are still many birds that could be observed around the area, seen on the photo. All of those birds seem to look like some kind of herons.

I first wondered, even with their habitat gone, how are they surviving? I also thought to myself, what are the species of these birds and what do they usually eat for sustenance? Finally I wondered, that since they are surviving, is there a new ecosystem forming amid the ruins? With these questions on my head, I started to research about them.  However, I could not find out what are those. In order to find the answer I should use more Internet websites to find out what kind of birds they are, and how do they survive. I also can ask local construction workers, as they might have observed these birds more than I did. This photo has been taken a few days ago, and I still see many birds around the area. This made me realize, even with the natural habitat gone, many species find a way to survive. This can relate to our Environmental Science Class that they are able to adapt their habitat in order to survive.

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