Desperate Drakes Kill Feisty Duck

After caring for Feisty and her brood of 9 for nearly 6 weeks, she and 7 of her ducklings have been killed. 
I am gutted by this disaster, especially since I reared Feisty herself as a duckling in 2012.
She produced 2 broods last year all of which were killed by crows, this year I was certain she would succeed by keeping them safe until half grown before releasing them back to the river. I did not reckon on the desperate Drakes anxious to mate with any female duck they could catch, and this was the fate to befall Feisty.

From the moment I released her with the brood she was pursued relentlessly by many drakes, to the point where I tried to intervene to stop the onslaught and allow her to care for her brood. The day after release she was getting exhausted and I managed to chase the drakes away long enough for her to hide under the bushes on the riverside. 

Meanwhile the Crows were picking off the ducklings two or three a day since Feisty could not look after them. I realised the situation was critical and took the net with me 3 days after release to try and catch the surviving ducklings. I searched for Feisty in the bushes where I last saw her hide, and found her body

 - it was heartbreaking for me. In addition I could not get the remaining 3 ducklings since the tide was against me, and when I returned the next day there was only one left which I managed to catch. Later I heard from a resident overlooking the river that a few hours earlier, another of the ducklings was being attacked by a Crow and he chased it off and retrieved the injured duckling that he then gave to the SPCA. I have not yet heard how it has fared. (UPDATE : Phoned SPCA today - the duckling was put to sleep because of injuries.) 
I have seen another duck killed by Drakes attempting to mate earlier this year, they can be pretty brutal regardless of the condition of the female. Females lose about half their bodyweight laying around a dozen eggs, and are in a weakened condition when they hatch their brood. Being pounced on by as many as a dozen Drakes and unable to escape, ducks sometimes get killed, and their orphaned ducklings taken by Crows and gulls. Drakes usually begin to calm down during the hot summer weather when they start to moult, something which we have not yet had !  Although this is June it feels like early April - this might have some bearing on why the Drakes are still switched on to mating.
Feisty's one surviving duckling will only be released when ready to fly, I sincerely hope it's a female like feisty !