Mute Swans allowing previous Cygnets/young to stay

We have a relatively new pair of swans at our local park pond {previous male died of bird flu}  This is the new pairs second lot of Cygnets just hatched.  The male has been incredibly aggressive and sadly our ducklings cant enter the pond as they are killed.  Their previous cygnets stayed well beyond the usual time period and two of the 5 were finally chased off the pond only in the last month or so {im assuming they were male?} but the adults have allowed the remaining 3 Young adult swans to stay which seems odd? everyone has said surely once the cygnets hatch they will be seen off but far from it. Infact the young swans have been up next to the nest only since the new babies have hatched. Is this rare? i cant find any information online of similar situations. Would they of kept them around as extra protectors?? its just so different to our old pair, who were much less aggressive during breeding {not killing the ducklings} and saw their young off after the normal time. im so curious 

Thanks 

  • In addition

    Today the 3 young swans that the adults have allowed to stay are now trying to kill the cygnets. They have killed 1 of 7. And have taken over the small island where the nest is forcing the adults and new cygnets off the island. I’m baffled as to how the adults are allowing this to happen. The Cob seems more concerned with killing tiny ducklings than chasing off these young that are a threat to their new brood
  • Last years cygnet's are still in our park too, but in the opposite end of the lake. For the first time yesterday I saw the adults go up to the cygnets end and there was a bit of aggro but nothing seems to have come of it.

  • I've subsequently seen a few repeats - the cygnets are of course of a size where they don't need to be intimidated. The adults now have four new cygnets.

  • Yesterday I took some surplus bread to the park - I know it isn't recommended but I reckoned a bit more wouldn't hurt. As usual one of last year's cygnets was sitting on is own a little way from the other four. I dropped some bread near the four and they didn't seem interested at first but the solitary one came up to me almost as if to ask what was in the bag and when I offered it some he was really quick to gobble it up, and his siblings then seemed to  decide my initial offering was acceptable.

    Mom was sitting by the path at the "adult" end of the lake with the four new babies, and as last year completely unfazed by humans - pigeons were seen off in short order though. The Canada Geese creche was just the same - one of the bigger goslings chasing off an adult duck!