The male will not grieve for a long period of time. Nature does not allow this. He may grieve for a day or two, but then he will go about his life.

As far as the eggs, it does not sound as if the eggs were being incubated for that long. It takes 35-40 days. For this reason, it is highly improbable that they will hatch. In fact, this would be the worst possible thing for the cygnets in the environment you are describing. They male will not take them back and will kill them. This means that you or someone else will have to raise them and they will imprint on humans (meaning the swans will think that they are humans and not swans). This imprinting will result in the swans never being allowed to live in any setting other than a captive setting where they are penned and safe from predators. You cannot teach them how to eat, how to recognize and escape predators or how to be a swan.

Finally, we would strongly suggest that you just take the eggs and throw them in the pond. If the swans begin to rot, they will explode and you will have a major mess in your house. Unless you know what you are doing, have a professional incubator with constant and controlled egg rotation, humidity and heat, they will not survive. Most swan breeders have a difficult time incubating swan eggs, so it is unlikely that you will get any cygnets. Rather, just a major mess in your house. Do not place the eggs in a trash can or anywhere in your house as this explosion can be significant. The eggs need to be placed in the pond and let the turtles feed on them so that they can mitigate the damage of an explosion. The Regal Swan