The crimson rosella is a beautiful and captivating mid-sized parrot native to Southeastern Australia. They can be found in a variety of forest habitats along the coasts and mountains.
Crimson Rosellas love to feed on nuts, seeds, insects, fruit, and nectar.
In captivity, they can make a good pet if hand-reared but are generally not as tame or friendly to humans as other parrot species. As a rule, they do best in a large enclosure or aviary.
Male and female crimson rosellas look quite similar. Like many parrots, they are sexually monomorphic.
This means that to the untrained eye, distinguishing male from female is very difficult, if not impossible, since they are very nearly identical.
However, there are several subtle differences in size, shape, and behavior that can be used to sex crimson rosellas.
Keep reading to discover some of the key differences between the sexes of this charming parrot.
Additional reading: Best Talking Birds for Beginners
Coloration
Male and female rosellas are very similarly colored. Both sexes are painted brilliant scarlet, with blue patches on their head, wings, and tail.
Females in some sub-species may display a dark green patch on their rump above the middle of their tail feathers, while males lack any such patch on their rump.
Males will often show more intense blue coloration on their cheek patches than females.
As a rule, coloration is not usually enough to make a positive gender identification on its own since it can be variable depending on the individual bird.
However, in combination with some of the other traits listed below, it can be a great piece of supporting evidence.
Body Size
Body size is a good distinguishing characteristic to separate males from females.
Adult male crimson rosellas are ten to twenty percent larger than females. Males can be ten to fourteen inches long, weigh on average one hundred fifty grams, and have a wingspan of six and a half to seven and a half inches.
Male parrots tend to be noticeably larger than their female companions across many different species of parrots. The reason behind this comes down to competition and sexual selection.
Since males compete against other males for the right to win a female, evolution has favored bigger males over time. This sexual dimorphism in size is apparent in the crimson rosella even from a very early age.
Fledgling males just out of the nest are already larger than their fledgling female brood mates.
While a twenty percent difference in size is not glaring, it will be noticeable to the attentive observer, especially if making side-by-side comparisons of individuals of both sexes.
Beak Size
Beak size differs between the sexes and is one of the most reliable traits to visually distinguish the two.
Males tend to have larger beaks, while females have smaller beaks. Male beaks are also wider than their female counterparts.
Like with body size, these differences are most obvious when making direct side-by-side comparisons between two birds of the opposite sex.
Head Shape
The keen observer can use head shape to help distinguish male from female birds.
Male parrots tend to have flatter and wider heads. Females, on the other hand, have rounder and smaller heads.
Behavior
There are a few behavioral differences between males and females of the species.
Generally, males are more aggressive and territorial than females. Females are said to be calmer and less territorial than males.
However, a paired female will exhibit aggressive territorial behavior if kept with other crimson rosellas in the same cage.
One last note on behavior is that all birds are unique, and these are only general expectations. Much depends on the individual crimson rosella, how it was reared, and how it is currently being kept.
Another behavioral difference came to light thanks to research done on wild crimson rosellas.
Both males and females share the burden of providing food for their young. A study from a university in Australia has shown that males tend to bring slightly more food to their chicks than females.
Males also feed the oldest chicks more so than the younger chicks. Females, on the other hand, feed chicks of all ages equally, though they bring in less food on average.
Another difference in male and female behavior is that when feeding, the female spends more time in the nest cavity.
Additional reading: Female Quaker Parrot Behavior
DNA Sexing
To be completely sure of the sex of your parrot, molecular sexing is the best tool to use.
Just as with humans, males and females have different chromosomes, and a genetic test is able to perceive these differences.
Males only have a Z chromosome, while females have both a Z and W chromosome.
Surgical Sexing
Another surefire way to distinguish male from female is through surgical sexing.
This is an older and more primitive technique than DNA sexing, but it is just as accurate. Surgical sexing involves visually checking the reproductive organs of the bird to determine whether it is male or female.
Since the reproductive organs are housed internally, surgery is required.
First, the bird is anesthetized. Next, the area where the incision is to be made is shaved of all feathers and sanitized.
A small incision is made, and an endoscope is gently inserted into the opening. Once the veterinarian has determined the gender of the bird, the endoscope is retracted, the incision is sewn shut, and the bird is nursed back to health.
For obvious reasons, this method is no longer used nearly as much as it was, as it can cause considerable pain, stress, and risk of infection to the bird.
Conclusion
Distinguishing male from female crimson rosella is no easy task.
Like other parrots, they are monomorphic, meaning male and female, and are nearly indistinguishable.
However, the subtle differences in body size, body shape, bill size, bill shape, coloration, and behavior outlined in this article can all cumulatively point to gender for the keen observer.
If in doubt, two scientific techniques, DNA testing and surgical sexing, can eliminate all confusion, though DNA testing is by far the easier and more humane choice.