Friday, May 30, 2008

Determing The Gender of Pigeons

Recently I had a fancier who is relatively new to pigeons ask me about sexing birds. I have a few thoughts on this--don't I always? :-) --and I would be curious to hear what others have to say about this.

Immature Pigeons Attempting to sex immature pigeons is usually a waste of time. Unless you have specific genetics involved (see below) as far as I know it's practically impossible to sex pigeons before they reach sexual maturity.

Slower Maturing Breeds Some breeds of pigeons mature more slowly than others. I saw Dr. James Gratz's article in a recent issue of Purebred Pigeon magazine about sexing frillbacks and he mentioned that they can be slow to mature. I have Old Dutch Capuchines and they seem to be a little slow to mature too.

Checking the Width of the Pubic Bones You can feel the pubic bones on the bird <http://en.wikipedia.org/wiki/Bird_skeleton#Skeletal_system>. The gap between the pubic bones should be wider on a hen (to let the egg pass out). However, the gap on a male runt will be far wider than the gap on a fantail hen so you need to have a known female or male of the
breed you're checking to get an idea of approximately how wide the pubic bones should be. And the wise fancier remembers that there is almost always some variation in nature.

In relation to this a very knowledgeable fancier of my acquaintance had this to say about this technique:

I've asked a lot of learned people and experienced fanciers about this vent stuff and there doesn't seem to be any sexually dymorphic constant in vent bone width. I haven't found any information based on statistical analysis to prove this apparent "wags tail" as any more reliable then a washer and a string. In Willard Hollanders' Origins and Excursions in Pigeon Genetics he states that beak length in wild pigeons can be sexually dymorphic but this relationship does not hold up in domestic fancy breeds.

The "washer and string" he's referring to is documented below.

Genetics to Help with Gender Determination Certain matings will result in certain colorations in the offspring. Rather than risk increasing the sum total of incorrect information floating around the internet, I'll refer those interested in learning more about these
matings to this page: <http://www.angelfire.com/ga3/pigeongenetics/SEX-LINKAGE.html> by
Frank Mosca that gives an excellent explanation of how sex-linkage in genetics can help a fancier to determine the gender of the result of certain matings. Texan Autosexing Pioneers were developed to allow commercial squab houses to easily sort out their young pigeons by gender and they take advantage of another sex-linked mating.

Observation of Behavior I feel the best way to determine gender is to simply put the bird which is unknown into a confinement pen next to a bird that is a known gender. Then watch how they react to each other. If you put an unknown next to a male, the male may ignore the
unknown or he may start crowing and puffing up his chest and dragging his tail. If he ignores the unknown then you haven't gotten an answer yet. But if he starts crowing and puffing up his chest then the unknown is likely a hen.

You can, of course, do the opposite with a hen; putting a hen next to an unknown pigeon may cause the unknown to crow and drag his tail and court the hen.

DNA Testing Dr. Gratz mentioned in his article that he uses an avian DNA testing service. This is always a possibility too.

Vent Sexing The following text comes from a fellow pigeon fancier. I'm a little hesitant to put it here because I'm afraid some people who don't know how to do this technique correctly will try this and injure pigeons. I would consult an avian vet if you're unsure how this technique works. How one goes about stimulating a male pigeon (other than putting him next to a hen) is a question for which I do not know the answer. And if you stimulate the male pigeon by putting him next to a hen, you don't need to open his vent to see which he is.

Pigeons can be vent sexed like chickens when they have reached sexual maturity. You use a Baby Nasal Speculum to gain access through the vent. If you stimulate the vent area and then open it up with the speculum you will be able to see the male sexual organs after stimulation. It is the same proceedureused in stimulating the male bird when using artificial insemination.

Washer and String Certain pigeon fanciers believe that it's possible to tie a washer to a string and hold the washer above the pigeon which has an unknown gender. I don't know that it has to be a washer; I believe any bit of electically conductive metal is supposed to work. I can't remember exactly how this is supposed to work--I think the string is supposed to swing back and forth in the same plane if the bird is one sex or around in a circle if the bird is the opposite sex.

Personally I think this is an example of what psychologists call "ideomotor action":

<http://www.straightdope.com/classics/a1_168.html>
<http://en.wikipedia.org/wiki/Ideomotor_action>

It's important to note that people don't have to be intending to deceive anyone for this ideomotor action to occur. People can be (and are) honestly unaware of the fact that they're causing the motion.

In brief, I think the fancier probably has a guess which one the bird is and, without realizing it, they make very subtle movements that either cause the washer to circle or swing back and forth. It would be easy to test: Have someone who's blindfolded hold the string and washer above a bird. Or attach the string and washer to a fixed stick. But as they say in the first article I linked above, people want to believe there is some magic in the world and pigeon fanciers
are no different.

At any rate, I know there are some intelligent, experienced fanciers for whom I have a lot of respect who swear this washer and string method works; I suppose if nothing else they'll be right half of the time. But a person would be right half of the time by flipping a coin too.

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