What stimulus sets off the breeding cycle of canaries? Since spring and summer is the usual breeding season for songbirds, the phenomena has been widely investigated. While the intensity of light, diet, temperature and other conditioning factors may influence the nesting instinct and fertility, only the springtime increase in day length has a predominant influence. In an experiment to test the relative values of light versus heat as a fertility stimulus (Suonalainen-1937) birds kept outdoors showed equivalent fertility to those indoors where both groups were subjected to longer days. Conversely fertility development did not occur to either group on short lighting periods regardless of temperature. Even ducks on a starvation diet when subjected to 15 hour days for three weeks responded positively to sperm development (Benoit-1950). Further experimentation by young male ducks illuminated by lights of equal intensity, but different colors show a maximum response to red, a very feeble response to blue and none at all to infrared (Benoit-1950). Birds subjected to 190 foot candles of illumination and 10.5 hour days showed no sexual development (Burger-1939). However, a weak red light of 1.7 foot candles intensity was sufficient to induce complete fertility when applied for long days (Bissonette-1932). In their experiment full fertility was observed at a minimum of 0.7 foot candles. Additional complexities of the photoperiodic mechanism was revealed by experiments involving the interruptions of the dark period by short periods of light wherein mature sexual development occurred. (Kirkland and Leopold-1952). Interrupted dark periods may increase photoperiod stimulation.

Photoperiodism

For centuries Japanese have practiced the art of yogai, the practice of forcing cage birds to sing in midwinter by lengthening their days by candlelight for three or four hours per day after sunset in the fall. The Dutch similarly stimulated various finches to sing prematurely in October for the purpose of enticing fall migrating finches into traps. Poultry and turkey breeders routinely stimulate egg laying by illumination of coops for added hours of light. No other type of external stimulus including heat, exercise, wakefulness, diet or rain has been demonstrated to induce fertility or mating behavior. The natural breeding season for songbirds between 40° and 50° North latitude commences about March 1, peaks the latter part of May and tapers off abruptly in mid-July (A. Baker).

In order to distinguish night from day your birds require contrasting light intensity. On sunny days or cloudy days the lighting intensity may approach 100 or 200 candlepower, whereas a moonlight night only a couple of candlepower is observed. This results in a ratio of at least a thousand to one. Recent research has indicated that birds have difficulty distinguishing between night and day if the intensity ratio is less than 10 to 1 (Etches-1988). A couple of years ago an acquaintance reported eggs at the end of the breeding season in September. Recently the same breeder had babies hatch in mid-November. obviously these birds do not recognize daytime from nighttime. Investigation revealed a relatively low lighting level in the flight cage and a 7½ watt white lamp used for nighttime lighting year round. Consequently this environment does not provide a ten to one ratio.

With American Singer shows being staged earlier into the fall months to avoid conflicts with older more established show dates it becomes a management problem for breeders. Males sing to attract attention to themselves. It is their method of attracting a mate and establishing and defending a territory to nest in. The objectives of the American Singer breeder is to advance the daylight hours to stimulate song without interfering with the breeding process. Most breeders do not have the luxury of being able to provide separate rooms for hen and singers. When singers are exposed to too many hours of light they are apt to lose their good tonal qualities and commence a harsher mating song. For hens the extra hours of light commences the egg laying process which really complicates mating management. For those who do not modify the natural scheme of things by providing artificial lighting the usual mating dates are from St. Patrick's day to the first of April. On St. Patrick's day in Colorado we have 12 hours of sunlight which would apply to similar latitudes in North America. The natural mating period can be modified but the following management practices must be followed.

1- The flock must have a summertime resting period so as to provide approximately 3 hours differential between resting period and mating date. In Colorado the shortest day of the year occurs in late December and this gives just over 9 hours of sunlight. The longest days occur in June and July with about 15 hours of sunlight. In Colorado the natural 3 hour time differential occurs on St. Patrick's day.

2- The day and night lighting intensity should be no less than a ten to one ratio and preferably even greater. It is a necessity to have a night light in the breeding room so the babies do not become chilled if the hen is caught off the nest when the lights go out. I personally use 7½ watt red bulb which is plenty for a 10½ X 13½ room. Above all else do not use a white or clear lamp. This turned out to be unsatisfactory for my bird room when I couldn't find a red bulb.

3- Birds to be mated should be put together no earlier than the 12 hours of light. I personally think 12½ hours is even better, but in any event the hens condition should be observed. As optimum breeding condition is reached the hens belly and vent provides unmistakable evidence that the hen is ready to breed. A hen begins to lose her belly feathers, the belly becomes rounded and bullet shaped in relationship to the vent and red inflammation will be observed around the vent at the optimum mating time.

The enclosed lighting schedule is offered for those who wish to mate their birds between January 1st to January 15th. If you wish to mate your birds March 1st to March 15th merely change the beginning and ending dates by two months. A word of caution for those who turn up their lights for the purpose of energizing their singers song; 11 hours is probably safe for quality song but 11½ is getting risky and 12 hours is out of the question.

It stands to reason that we do not all have the same aviary conditions. In the case of my Illinois bird room it was located above ground with a double window facing South. With this bird room there is no necessity for artificial lighting except in the shorter day fall months when artificial lighting was used for the purpose of feeding, cleaning and training of my singers. When January rolled around I merely set the timer up 3 hours and commenced raising babies. There are those who emphatically state that you cannot adjust the lighting that quickly as it must be done gradually. As evidence that it worked quite well for me; in mid - March I moved my wife and 38 baby American Singers from Chicago to Colorado and in one round ten hens averaged 3.8 babies per hen with three hens raising 5 babies. Turkey breeder farms have long since abandoned the practice of extending daylight hours gradually. I got the tip from my son who has a degree in avian science and has managed breeding flocks in Minnesota and Colorado and presently manages a hatchery. However, my Colorado aviary has a quite different set of conditions and my Illinois management practices proved to be totally inadequate. My present bird room is totally below grade with only a window well in one corner. Consequently artificial lighting must be utilized the year around as the area is totally lacking in sunshine for illumination and the health benefits of ultraviolet rays. This lighting schedule is similar to those utilized by other successful breeders and has been modified particularly for use by American Singer Canary breeders. I am using this program for the fifth year and my hens go readily to nest and fertility is excellent.

Copyright © 1998 Bill Summers. All rights reserved.

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