park

Today when I went to the park, it was cloudy but the sun could shine through the clouds, so it seemed sunny.
When I was nearing the harbor, I saw some robins on the road and in a yard.
When I was out on the breakwater, I saw a sea gull and a cormorant.
When I was almost at the beginning of the park trail, I saw some ducks and mergansers out in the water.
I also saw two shorebirds on a rock that was nearly all the way underwater.
When I was in the park nearing the battle site bench, I saw a group of people, mostly kids, a little ways off the trail and there were some things set up a little ways in the trees.
When I was at the battle site bench, it was sort of high tide, and I saw a bunch of sea gulls on the beach and in the water.
When I was on the trail by the river, I didn’t see any ducks.
When I was nearing the foot bridge, I saw a trail camera set up in a tree angled down at the trail. It was far enough up that someone would need a ladder to reach.
Why was the trail camera set up there?
How long has the trail camera been there?
What was the group of people doing?