Great photos. We can't tell how the swans are getting to the feeder or on top of the concrete slab. Are they walking on the rocks? If so, this is not good. The feeders should be placed in the water so that the swans do not need to leave the water to feed. The present feeder will attract pests (flies, rats, and ants). You may need 2 feeders at each end of the pond. The feeders should be made from the Blitz dog feeder and placed in the water. This will keep the swans from climbing on the rocks.

We also cannot see where the grass is located and again, how the swans accessing this area. We would suggest that you place a pen on either side of the gazebo (one for the black swans and one for the mute swans) during nesting season. As both species may mate during the spring and produce a clutch, you will need 2 pens.

The area on either side of the gazebo is free from rocks, smooth and sandy. This will make an excellent area for pens as you can also add straw or hay onto the sand. Once nesting season is over, remove one pen and add some grass, petunias or other grazing material such as rye grass. Hope this helps. The Regal Swan