I got three runner ducklings and a drake in May. For three weeks now I have been getting a large greenish shelled egg nearly every day which I think is my black runner Marmite. The other two (caramel and apricot) are a bit younger (judging by when they started quacking) and I have had four or five variously sized white shelled eggs, some without a yolk. However for the past week no white shelled eggs at all. I have checked their pen and water thoroughly and raked through their bedding. They seem happy. I have picked them up and checked that they are ok. It has got colder and days shorter here but marmite is still laying. Any ideas? Do I just need to wait til the warmer months again?