If the head/neck was stripped it was either a coyote, fox, bobcat or panther. You need to find the male swan and bring him in (shed, garage, or other safe area free from any dangerous chemicals, access by predators such as dogs, cats, raccoons, and with adequate, but not direct ventilation) for several days until the predator leaves the area. The predator will return so if you can build a safe pen (enclosed top to bottom so predators cannot climb over or dig under the pen) with a large water feature, bank area (zero entrance with no steep banks or abrasive substrate) and feeder inside, your male bird will do just fine. If you release him back onto the open habitat, he will possibly face the same demise.

On another note, male swans will usually not re-pair if something happens to their original mate, so trying to find another swan is not suggested. The last thing you want to do is place another male swan on the habitat as they both may seriously injure or kill each other. Again, the male swan will do just fine on his own, but in an enclosed habitat.

2. DO NOT try to incubate these eggs. Unless you have a professional incubator with proper humidity, egg rotation and heat, the eggs are not going to hatch and you are going to have a massive messy explosion. DO NOT place the eggs in the trash, you want to take them back to the pond and place them in the water so if they do explode, there will not be any problems. Swan eggs are extremely difficult to incubate and many experienced swan keepers cannot bring the eggs to viability.

We hope that this information is of benefit to you. The Regal Swan