At the Window Again

Lately I have to check to see if there are swimmers in the water whenever I get home. In the afternoons on Saturday and Sunday I have been finding them lately. Today was the same.

The raft had gone just out of sight before I got the camera out - the children (maybe adults?) were all frolicking in the water

But today I observed an added twist. Two boys/men were actively working on something. Are they  fishing? What are these two looking for? What is valuable to find along the shore?

I noted two swimmers traveling along the edge with something blue between them  and then they would come up on shore

It looked full but the water sieved right through

From this distance I could see little and they would go back in, so I don't know if they found what they wanted

After a minute they would flip the blue bag/sheet/net/thing 

I couldn't tell if there were fish they shook to the bottom and kept fishing or if they didn't find anything

Then back they would go with the blue between them

I think they were going with the current but swimming faster

This is what caught my attention further up the river and I watched them come up and out and in several times

Hope they found what they were looking for - Sure wish I knew what it was/is!!!