I may be the rebel of the crowd, but have you considered keeping a few more boys in order to increase your ratio of hatching females? Some breeds (Jersey Giant especially), especially those with broiler ancestry, prefer to have many males in a flock. Think about it, in the days of professional poultery, a poulterer who was paid by weight would prefer to sell as many (heavier) roosters as he could, and could charge more ounce for ounce than a hen too because lower prep time (1 big bird vs 2 small ones) increased demand. Roosters were also considered more flavorful than hens, and whether whole or dressed made a more handsome presentation. Just like with Tom turkeys, ganders, and mallard ducks, they pushed rooster/hen ratios in their flocks to satisfy customer demands and increase profits. Boys sell better! The birds got used to this (in many ways, it is the more natural way to raise them anyway), and passed those social instincts down to their descendants, who populate our flocks today. Harem-type flock ratios (as high as 30:1 female) are a post-Industrial Revolution trick intended to encourage high-production egg laying, and rarely make for happy birds. Personally, I consider harem flock practices unhealthy and exploitive, and would never raise chickens without multiple quality roosters, though I understand I am in the small, quiet minority on that issue. Given the chance to brood, a hen in such a flock will take the opportunity to "improve" the ratio by hatching more boys. Keep in mind, cockerels are for more than mating. They scout new food sources, solve quarrels, round up wanderers (especially chicks), and most importantly, draw predators away from the chicks and hens. Their territorial displays keep the hens sexually stimulated, and keep rivals from neighboring yards from encroaching. They also determine when a flock is too crowded, and given the opportunity will occasionally split off with a female volunteer or 2 and start a new flock elsewhere. If a broody hen feels like these needs are not being met, she will prioritize hatching and raising sons to fill the void. It's hormonal. You raise silkies, right? That's not a production laying breed by any means, so they would not be used to female-skewed or harem flocks in either their hormones or their social behaviors, so they will be more likely to naturally skew their reproduction to favor males, especially since they know you give away most of them, so they must raise more just to keep a few. Remember, Silkies have some of the strongest mothering instincts in all of chickendom. If they want more males, it's unlikely you can convince them otherwise. Maybe you could try keeping 1 or 2 extra males (good solid attentive roos, not scraggly rapists) and see if that improves next season's pullet count. If you're worried about them fighting, let the aggressor have some time alone in the coop or a separate pen within sight of the others. Otherwise, let them fight! Good roosters very rarely harm each other, they just puff up and let off steam. Father-and-son and brother teams do wonders for flock morale, not to mention security. Broiler breeds (like my Jerseys, Brahmas, and Marans) can be quite aggressive without enough males around. Hens will fight, bully, and peck open eggs to display dominance, and roosters, overstressed with too many female demands, will be rude to hens and chase, attack, or bareback them. Ironically, most would tell you to add more females in that case, which makes the problem worse. I'm not saying every breed is like that, and when it comes to Silkies, I don't really know. To most chicken owners, I would say, when it comes to boys vs girls, pay attention to the needs of your flock and don't get greedy. Of course, if you're using an incubator, none of what I said really matters, and good luck!
