park

Today when I went down to the park, it was partly sunny and there was still snow on the ground and some of it was a bit icy.
When I was on the breakwater, I saw some sea gulls and ducks.
When I was in the park, I saw four geese and some ducks and sea gulls out on the beach. The four geese were on opposite sides of the water from each other, two of them one one side and two of them on the other.
When I was at the battle site bench, it was low tide and I saw some sea gulls and people out on the beach.
When I was nearing the trail by the river, I saw some swans flying from the river through the trees, I also heard them.
When I was on the trail by the river, I saw two swans far up on the grass and I saw some ducks.
When I was on my way back home, I saw a great blue heron flying around and making noise. I saw it fly over at least two times.
Why did some of swans fly away?
Why did two of the swans stay?
Why was they great blue heron flying around?