I'm afraid you're right - the little cygnet disappeared overnight, and it was undoubtedly taken by one of the many predators at the lagoon. The minute the swans take a cygnet into the water the danger is there. The parents can protect their young from some predators, but this year we have a plenitude of river otters, mink, raccoons, herons, seagulls, even a Bald eagle that sits on a nearby log a good part of each day, and last but not least, the huge carp in the lake (I've personally seen the fish grab ducklings). Mink strike from underneath and can snatch young even when parents are on either side. We'll never know for sure what the culprit was.

It's sad indeed that conditions are not friendlier for the swans. We can only be grateful that the adults weren't harmed.

Thank you so much for your kind concern.