No way to know for sure. Is he a fairly young bird and new to the nesting thing? We had a first year nesting male do the same thing last year and I just contributed it to a lack of maturity/experience! He could have been run or scared off. Hunger should not enter into a mature male's nesting behavior, the poor birds go into a daze and don't usually eat during the whole nesting period, losing up to a third of their body weight. Some owners sprinkle a little food and set a small bowl of water within reach of the bird in the event that it finds the need to eat. In the wild, they pretty much survive by licking the dew off the adjacent vegetation. Last season, we gathered the abandoned eggs and finished hatching them in an incubator.