If there is a large amount of feathers in an area, it usually means an attack by a predator. If she survived and was not seriously injured, she may have flown to another area and will return after her nerves have settled. Give it a couple if days to see if she returns.

Usually, not always, but usually a male swan will not re-pair with another swan after the loss of its mate. This is totally dependent on availability of other females in the area, age of the male swan (the older
the less likely to re-pair), the individual attributes/behavior of the male swan and if the swan is wild and can fly to another area to meet other females.

Yes, he may call for her and grieve, but this will be very short-lived. Nature does not allow wildlife to grieve for large periods of time as in humans. To do so in the wild would not only be detrimental to the individual member, but the entire flock. His job is to work to stay alive, not grieve.

The last thing that should be done is to introduce another swan unfamiliar with the habitat to meet the same fate as the female. Swans unfamiliar with the habitat are easy prey to predation. To introduce a new swan would involve building a predator proof pen that would allow for the slow introduction of the new swan to the habitat and the male swan. This introduction period, approximately 2 weeks will allow you to monitor for signs of aggression by the male. He could accidently or intentionally hurt her if she is rejected. Now, you have the possibility of the new swan being introduced only to be seriously injured or even killed due to rejection. If rejected, you would need to find another home for the new swan.

Finally, Massachusetts DNR is following the same misguided killing of Mute Swans as other states. Misrepresentation of Mute Swans include their being non-native and invasive, yet current scientific research is dispelling this non factual information and showing that the Mute Swans are actually a Sentinel species that alerts scientists to problems in the environment. U.S. and state wildlife entities are killing Mute Swans under the guise of conservation and misrepresentation so that the public will buy into the killing programs. The ulterior motive is to remove Mute Swans from their habitat, kill them and introduce a larger Trumpeter Swan for Trophy Waterfowl hunting purposes. This is how wildlife agencies fund themselves, through hunting permits and Trophy hunting generates larger funding. So, you could introduce another swan only to have the Massachusetts DNR kill it and your surviving swan.

For the above reasons, we would suggest that you allow him to decide if he wants another mate and let him go look and choose rather than you. If he chooses to live alone, he will be just fine. There are probably other waterfowl species, i.e., ducks and geese that he can talk and pal around to avoid loneliness. The Regal Swan