Hens can and do crow, and it’s more common than most backyard flock owners expect. The two main reasons are social dynamics (a hen stepping into the rooster role in a flock without one) and a medical condition called sex reversal, where hormonal changes cause a hen to develop male characteristics. Which one is happening depends on whether crowing is the only change you’re noticing or whether your hen’s body is changing too.
The Dominance Explanation
Chickens maintain strict pecking orders, and those hierarchies aren’t as stable as people once thought. Research on laying hen flocks has found unexpected rank instability, with active rank changes triggered by rehousing, breeding shifts, and the absence of males. When there’s no rooster in the flock, the highest-ranking hen sometimes takes on rooster-like behaviors, including crowing, mounting other hens, and acting as a sentinel for predators.
This is purely behavioral. The hen’s body hasn’t changed. She still has a functioning ovary, still lays eggs, and still looks like a hen. She’s simply filling a social vacancy. It’s most common in small flocks with no rooster, but it can also happen when a rooster dies or is removed. Even in flocks that do have a rooster, a particularly dominant hen may occasionally crow, though it’s usually quieter and less frequent than a true rooster’s call.
Sex Reversal: When Hormones Shift
The more dramatic explanation involves actual physiological change. Female chickens have a quirk of anatomy that makes this possible: only the left ovary is functional. The right side contains dormant tissue that never develops under normal circumstances. If the left ovary is damaged by a cyst, tumor, or diseased adrenal glands, that dormant right tissue can activate and develop into what’s called an ovotestis, a hybrid organ containing characteristics of both ovarian and testicular tissue.
The ovotestis produces male hormones, and the hen’s body responds. Her comb and wattles grow larger and redder. She may develop pointed hackle and saddle feathers (the long, narrow feathers on the neck and back that are distinctively rooster-shaped). Her spurs may become more prominent, though it’s worth noting that many hens naturally grow small spurs even without hormonal changes. The crowing in these cases tends to be louder and more persistent than dominance crowing, and it typically gets more frequent over time as male hormone levels rise.
A hen undergoing sex reversal will stop laying eggs. The left ovary has to be significantly damaged or non-functional for the right gonad to activate, which means egg production ceases. This is one of the clearest ways to distinguish sex reversal from simple dominance behavior: if your hen is still laying, her crowing is almost certainly behavioral.
How to Tell Which One Is Happening
Look at the full picture, not just the crowing. A hen crowing due to social rank will look exactly like she always has. Same feathers, same comb size, same body shape. She’ll still lay eggs on her normal schedule. The crowing itself is often a rougher, less polished version of a rooster’s call, and she may only do it occasionally, often in the morning or when she’s asserting herself over the flock.
A hen undergoing sex reversal will show a constellation of changes over weeks to months. Watch for:
- Comb and wattle growth: noticeably larger and redder than before
- Feather changes: new feathers coming in with the pointed, glossy shape typical of rooster plumage, especially around the neck and saddle
- Egg production stopping: a complete halt, not just a seasonal slowdown
- Behavioral escalation: crowing becoming more frequent and louder over time, along with increased aggression or mounting behavior
It’s worth noting that a sex-reversed hen doesn’t become a rooster in the full sense. Her chromosomes are still female (ZW), and the ovotestis rarely produces enough viable sperm to fertilize eggs. She takes on the appearance and behavior of a male without fully becoming one.
What You Can Do About It
If the crowing is dominance-based and it bothers you (or your neighbors), the most effective approach is disrupting the pecking order. Isolating the crowing hen from the flock for a couple of weeks forces the remaining hens to establish a new hierarchy. When you reintroduce her, she loses her top rank and often stops crowing. Adding a rooster to the flock, if your local ordinances allow it, also tends to eliminate hen crowing quickly, since the social role is filled by an actual male.
If sex reversal is the cause, management is more complicated. The underlying issue is damage to the left ovary, and there’s no practical way to reverse that in a backyard setting. The hen won’t lay eggs again, and the crowing will likely continue or increase. Some flock owners simply accept the change and keep the hen as a non-laying member of the flock. Others rehome her if noise is a concern. A veterinarian can confirm sex reversal through a physical exam or hormone testing if you want a definitive answer before deciding.
Does Crowing Affect the Rest of the Flock?
A crowing hen doesn’t typically cause problems for the other birds. In dominance situations, she’s actually providing some of the same benefits a rooster would: watching for predators, calling other hens to food sources, and keeping order. The flock generally accepts her authority the same way they’d accept a rooster’s.
One thing to watch for is whether the crowing hen’s behavior triggers broodiness in other hens. Research on laying flocks has shown that rooster calls and presence can influence incubation behavior, and once a hen becomes fully broody, her ovaries regress and egg production stops for a significant stretch. If you’re keeping hens primarily for eggs and notice a drop in production across the flock after one hen starts crowing, breaking up broody behavior in the other hens early can help keep things on track.