Went to the San Diego River channel, on the Sea World side, so I could see what the birds were doing in the rain. Videos were taken from under cover of the open hatch back door, while parked at the edge of the road.
I found it interesting the way the water beaded on the ducks backs. I can see where the phrase "like water off of a duck's back" came from. As to the egret, I couldn't tell what the rain was doing. It did seem more affected by the rain than the ducks.