Martin,
You are right, he does prefer the eelgrass to the apples. I placed a bunch a apple slices around the edge of the pond and he hasn't touched them. Maybe when he eats all the eelgrass he will start eating the apple slices and I can catch him. Then I can plant more eelgrass.
Does the type of apple make any difference?
It is safe to shoot around the pond, but I have only seen him one time during the day. He is doing all his feeding at night.

Thanks for your help,
Larry