Is it natural for a male mallard duck to leave its wife and its eggs?

These mallard ducks have made a nest in a bush in my front yard. We use to see the male all the time looking for food but now hes no where in site. Therefore the female had to stay with her eggs all the time to protect them and when she trys to leave to get food the neighbourhood cats attack the eggs. Do you think the male will come back? Wil the eggs be okay?