Fallows – Part 2: Introduction


Fallow budgerigars have been regularly bred since 1930. It is published that at least three different mutations with a very similar phenotype/appearance exist. Fallows can be bred in the Green as well as in the Blue and Yellowface series of colours and in combination with most of the mutations. The wing colour of Fallows is described as pale brownish grey and the body colour is gradually diluted (to White or Yellow) with the original colour best visible between the wings on the back of the birds The cere is pink coloured in cocks and brown in hens. Throat spots are brownish and legs and feet are pink. The eyes are red. The English (and the Scottish) Fallows do not show such a perfectly white iris ring as do the German and the Australian Fallows. The colour of the iris ring appears to be the only visual difference between these mutations. In Fallows the black pigment is not altered to brown pigment. The visual effect is apparently due to reduced enzyme activity (German Fallows) and due to defects in melanocyte morphology (English Fallows).

A new page in the history of Fallows has been written recently. In 2003 a male budgerigar with red eyes was found in a pet shop by Kanji Kawabata. He bred with this bird -it was a Goldenface-Bergman-Blue Clearwing Opaline Fallow- and made public the Japanese Fallow. Based on his observations the Japanese Fallow mutation is autosomal recessive and has white iris rings, exactly like the German and Australian Fallows. He combined the Japanese Fallow mutation with the Clearwing, Danish Pied, Opaline, Violet, Cinnamon, Japanese Crest (“helicopter”) and the Goldenfaces. The resulting birds are unique.


Breeding experiments have shown that the English, Scottish and German Fallow mutations are not allelic. In other words mating of two Fallows from different mutations will result in offspring that look perfectly normal. These chicks are split for both Fallow mutations. The Fallow mutations are recessive and therefore only visible if two copies of the Fallow gene are present. Today it is not known whether one of the Fallow mutations is linked to a commonly accepted mutation or not (Dominant Grey and Australian Fallow? Spangle and English Fallow?). It is not known whether the Australian, Japanese and German Fallow mutations are allelic.

It may be anticipated that a Fallow mutation is allelic to the Non-sexlinked Recessive Inos.


Breeding of exhibition quality Fallows is a task for stubborn people with a thick skin. This may be the reason why some of the comments from the virtual experts appear to be very spicy. – Bonsai


SM: My birdroom is 60ft by 20ft (18m x 6m). It is a brick construction with two internal flights. The 48 breeding cages measure each 24in x 18in x 15in (64cm x 45cm x 37cm) and the corresponding outside nest boxes are 6in x 6in x 10in (15cm x 15cm x 25cm).

I do not believe that my birds are suffering by being housed inside. Lighting is provided by fluorescent lamps and is constant throughout the year (14 hours). Budgerigars, unlike many other species of birds, are not susceptible to light stimulation.

FM: We have two birdrooms. One birdroom with 8 breeding cages each 30in x 18in x 16in (75cm x 45cm x 40cm) and an internal flight measuring 8ft x 5ft x 7ft (2.4m x 1.5m x 2.2m). Nest boxes are 10in x 6in x 10in (25cm x 15cm x 25cm). I am a great believer in true light fluorescent lamps that provide a spectrum similar to natural light including the required UV light. The day length is adjusted to stimulate natural cycles. To optimize the breeding of birds you have to understand the role of circadian rhythms and photoperiods too. The timing of the artificial light is as important as the quality of the light. In general I suggest that the photoperiod is gradually increased from 9 to 10 hours to 15 to 16 hours a day within 6 to 8 weeks. Less than 9 hours of light per day appeared to abolish breeding condition. The second birdroom is an external flight with a connected small inside flight to guarantee shelter during the night from e.g. cats. Birds always move into the inside flight over night. During wintertime all birds are kept inside. It is feasible to condition budgerigars in a way that the first chicks are hatched precisely on the ring issue date if required, starting for example conditioning in September. If lighting is kept constant over several years birds will breed very well the first year but fail to breed in the second year. This observation I made at the very beginning in the fancy and I of course blamed the birds or the former owner of the birds. Depending on the distance of the breeding cage from the artificial light source you can even direct the sex ratio in the clutches (!). Move the cage closer to the source and you will have more cocks.

We do not use “ladders” to allow moulting birds to reach perches. In fact even moulting birds should be able to fly. The “ladders” found in many bird rooms are there to allow the overweight monstrous show potatoes to walk to the perches as most of them cannot fly anymore.


SM: Organization is essential in my bird room. Normally I check nest boxes twice every day. However when eggs are due to hatch I check more often to make sure that hatched chicks are being fed properly. A record card is attached to each breeding cage and notes are made about fertile, addled or damaged eggs. My feeding routine takes about 3 hours a day. Water is changed every day and cleaning is done every week, mostly at weekends.

FM: In the inside birdroom the light is turned on every morning and turned off every evening by a timer. The exact time depends on the condition of the birds and on the season. Our birds are fed every day and sufficient water is provided too but we do not stick to a defined routine. Our birds know that they will receive a delicious piece of greenfood when we enter the birdroom, but they do not know whether this will be at 6.00 a.m. or at 6.00 p.m. Nestboxes with chicks or with eggs due to hatch are inspected twice a week and records are updated accordingly. In our notebook we record the age of the breeding birds, the size of the clutches, the number of chicks hatched, the number of chicks fledged and the amount of rounds performed. We have individual files for all birds specifying all the details of the birds and the number and quality of the offspring. We do not mark eggs and we aim to cause as little disturbance as possible. Most of the time in the birdroom we simply sit there and observe. We spend a lot of time with particularly sympathetic youngsters. The “lazy breeder” method, also called “deep litter” method, is preferred. We do not think that a weekly disinfection is appropriate.


SM: I use a basic seed mixture that is composed of millet (Japanese, White, Yellow, Panicum), plain canary and grouts. Grit, cuttlefish and mineral blocks are always available. Hardboiled eggs are mixed with breadcrumbs and used as softfood every day during the year. The water is filtered and vitamin supplements are added throughout the year. Entrodex (probiotic) is added to the softfood.

FM: We feed a commercial basic seed mixture of canary seed and different millets. If possible the birds get greenfood every day. Our tap water is of very good quality and not chemically treated. Carrots or apples are distributed in the flights regularly. Mineral blocks and softfood are available for breeding pairs only. A commercial softfood is given to birds with chicks starting 2 to 4 days before chicks are due to hatch and removed after the chicks are fledged. We do not add vitamins to the food and the concept of stimulating a bird’s (or a human’s) natural intestinal flora is of course a marketing gag and nothing else (if your birds are not treated with antibiotics every month). It was shown that a raw protein content of 10% in the seed is sufficient for nonbreeding birds [see reference 1]. Also it is not necessary to supplement the food with the most critical amino acid lysine. We believe that the situation is different in breeding birds rearing a dozen chicks and we provide enough softfood with lecithin.


SM: Today’s showbirds are of such high quality that they are reacting more sensitively to invading pathogens as compared to wild budgerigars. I use Ramizol for treating trichomoniasis, Nystatin to control fungal infections, Virkon S to kill viruses, Chloromycetin to treat eye infections, Ivermectin to fight scaly mite and Mega-S to fight megabacteria. Amoxycillin and Cephalexin are used to irradiate bacteria.

FM: We do not treat sick birds with antibiotics or other medicine. We believe that the elimination rather than the cure of sick birds is a must if you plan to breed with your birds. Selection of healthy birds is the superlative medicine chest. It is clear from experiments with mice that a successful response to a pathogen (virus, fungus, bacterium, yeast) in a stud is directly related to the diversity of certain molecules found on key cells of the immune system. These molecules are required to initiate an appropriate immune response and appear to prevent inbreeding by directing the mate choice as proven in mice and also in humans (see reference 6) to  prevent matings between genetically similar individuals. Reproductive mechanisms are varied and range from selective fertilization to selective abortion. In inbred studs the diversity of these molecules is decreased. It is therefore not uncommon that a high percentage of the birds in an inbred stud cannot fight e.g. a particular strain of bacteria and will eventually die if not treated with high doses of antibiotics. Wide (and wild) application of antibiotics is directly responsible for the development of resistances in bacteria and fungi. The problems of Megabacteria (a yeast) are maybe due to a superinfection in the gut by bacteria (they open the gate) followed by the multiplication of normally inoffensive Megabacteria. Similar yeast infections are observed in immunocompromised human patients or not yet immunocompetent children. It is therefore not surprising that newly hatched chicks are very vulnerable and it is heartbreaking to hear that plenty of budgie breeders observe high juvenile mortality these days without apparent cause. The only scientifically (not psychologically) sound advice is to start from scratch with budgerigars that are selected for health. Maybe one should not buy budgerigars from breeders with a big medicine chest and a known history of Megabacteriosis. Megabacteria can be eliminated from the gut of your birds for a short period of time but they can never be irradicated from the environment of your budgerigars if you do not keep birds under quasi sterile conditions. Humans, especially children need fresh air and sunshine to be healthy and happy. It is not heresy to claim similar conditions for birds, especially breeding birds.

French moult is a widely distributed and devastating viral disease in budgerigars. Interestingly it is often found that not all chicks in an infected nest show symptoms. This may indicate that these unaffected chicks have the appropriate molecules on their cells of the immune system to keep in check or eliminate the virus. Budgerigars that have been suffering from French molt should never be used for breeding. These birds can recover completely and produce healthy chicks but they will transmit half of their suboptimal set of molecules to their offspring and may ruin your stud within few years if another outbreak of French molt occurs. Viral diseases can never be cured by antibiotics and you can anticipate the effect of antibiotics during viral infections if bacteria, important and protective bacteria are removed.

Outbreaks of French moult and Megabacteria can have disastrous effects in studs that have not been rigorously selected for health. By the inappropriate use of antibiotics and other medications you are constructing a rod for your own back and the back of the whole fancy.

In general we only obtain birds from people we know very well and we are very reluctant to allow visitors that we do not know to enter our bird room as it appears that Megabacteria and resistant strains of bacteria as well as French moult are now widely distributed in the fancy. Of course these bad bugs can be transported very easily as they are invisible and do not need a passport (not even a work permit).

New birds are housed for at least 6 weeks at a distance from our birds and observed for any sign of sickness.

A report published in the biggest budgerigar journal of the world [see reference 2] recommended 6 (six) different products for a six week quarantine, 9 (nine) different products for routine medication and 3 (three) additional supplements. Would you give all this bull dust to your children?


SM: I keep between 300 and 400 budgerigars and of these 2 to 5 are German Fallows. Most of the rest are Spangles, Cinnamons and Opalines in Grey green, Green, Grey, blue and Green. I also keep a number of Yellow faces, Lutinos and Dominant Pieds. This is probably too many, but I do believe that it is necessary to breed several hundred chicks each year to give yourself a chance to breed some outstanding chicks. I keep more hens than cocks due to the problems that are often related to hens. I do not consider myself as a Fallow specialist as I keep maximally half a dozen at any given time but do you know somebody that keeps more Fallows?

FM: We keep between 100 and 200 birds and of these 20 to 50 are Fallows or split Fallows. We aim to breed from 16 pairs every year three full rounds per pair. Our policy is to keep all birds from a pairing or not a single one. The brothers and sisters as well as the parents of a particular bird we would like to breed with are held back for at least one year. Some families are kept for years. We intend to observe each family as a whole to check for vitality, character, intelligence and longevity. It may occur that we keep more than 15 brothers and sisters from a distinctive bird that will never see a breeding cage from the inside. It may also happen that after a regular evaluation of a defined family, 4 sisters from one pair are used for breeding. We endeavour to have as many chicks from a pair as possible and we do not pair a cock to several hens in one season. Selection can only be applied seriously if you have a picture of the real potential of a given mating. This potential is reflected by the quality distribution of the youngsters.

Most of our Fallows are Opalines in all shades of blue including Violet. Some of the Fallows are Golden faces and we plan to breed Fallows with most of the established mutations.

Selection Methods

SM: I select based on visual qualities and pedigree. The visual quality accounts for 80% and the pedigree for 20%. The birds I keep have to be big birds with a lot of feather. Big heads with directional feathering and a lot of back skull is a must as well as big shoulders to carry the massive heads. I like to see a deep mask with evenly distributed spots and a tucked in beak. I also breed with the lesser brothers and sisters of the top birds from other breeders that I can buy. Selection in the aviary of a seller is as important as selection in my own aviary.

FM: Selection of the breeding birds is absolutely vital and mandatory for your stud. Our selection method is very simple. We breed with the best birds from the best families. The characteristics we are looking for are balance, balance and balance. The birds have to be good flyers with a lot of temperament and they have to come from fertile families on both sides of the pedigree. Our definition of fertility is simple. We require a pair of birds to rear at least a total of 9 chicks in three subsequent rounds before the offspring is considered for a breeding program. The mean clutch size has to be greater than six eggs. These are the prerequisites before we start to think about the standard of excellence. Of course we do not breed with featherless birds that have three legs or more than two heads. However in some odd cases we breed with peculiar birds simply because we like them without considering the above mentioned rules. The budgerigars we buy are normally in this category. We also realized that we have the tendency to breed with offspring from birds that have been bought. Our excuse is very lucid. We believe that these birds are very special and belong to the category of ravishing birds that are simply exquisite and therefore valuable. This is a perfect mirror of human nature and we are not willing to fight it even though we should anticipate breeding problems in the future.

Breeding Techniques

SM: My aim is to breed quality in quantity therefore I am a great disciple of related pairings if the original birds are of real quality. Aunt to nephew, uncle to niece or cousin to cousin are preferred matings. I do not pair birds with similar faults such as flecked birds, birds with hinged tails or small masks. The starting point for developing a winning line or family in my hands is always a good cock that is fertile and prepotent. This cock will be mated to 4 or 5 related hens in the first season to produce halfsiblings for the next year. Mating of these halfsiblings together provides me with the nucleus of a winning line. Occasionally these birds can be mated back to the original cock to fix established characteristics.

FM: We are great believers in assortative matings or mating of phenotypically similar birds. It is more likely that these birds carry the same or similar alleles for the desired morphology. However the more you try to cover the deficiencies in one bird with good qualities in another, the less the birds will have in common. If results are not satisfactory you should not blame assortative mating as that is no longer what you are doing. Peer reviewed data on inbreeding in budgerigars are very rare and results are controversial as the observed heterogeneity in response to inbreeding, resulting in increased or decreased reproductive success, may be attributed to environmental differences or to the history of individual strains [see reference 3]. So far we have not had the opportunity to start a defined inbreeding program as the backgrounds of the individual birds in question are not fully known or not satisfactory. Inbreeding with birds of unknown origin is a high risk and a short term project only, as it is known from experiments in mice that at least 95% of all lines started will disappear within 8 to 10 generations.

It is very difficult to forecast the outcome of a short term inbreeding program and it is impossible to predict the outcome of a long term inbreeding program.

The only sensible starting point for a winning line of exhibition budgerigars should therefore be several pairs of birds that are from a very well established line with a known history. The best method to breed consistently outstanding birds is to start with outstanding birds from outstanding breeders. These birds are very scarce and are not commonly for sale. To circumvent this problem you may apply another well established method: the fat wallet method. The fat wallet method does not work with Fallows as prepotent Fallows from established lines are not available.

Often breeding theories are reflecting the fantasy of the breeders not the facts that pass reasonable scrutiny. It is very human that we often confuse fantasy with experience, wishful thinking with success and myths with knowledge. Based on our experience we concluded that three very important rules are fundamental to all success. Unfortunately they are not known. In the meanwhile we apply  the best breeding technique that is successful on long term. This method is known as the KISS method: Keep It Simple Stupid.


What features have to be refined in your Fallows?

SM: The size, the head and the feather texture.

FM: The features they don’t have: Size, head and eventually balance.

What is your method for breeding marvelous Fallows?

SM: I have a large number of good budgerigars in all the mainstream colours. The Fallow gene is recessive to normal, therefore I use the standard method for improving recessives. I pair the best visual Fallows with the best outcross available. The best split young Fallow can then be paired either with split Fallows or with Fallows from the top of the stud. It is a long way to go. To improve budgerigars in general I use Dark greens for the colour, Grey greens for the size, Opalines for the spots and Spangles for the fertility. Flecked birds carry the feather I want and to dilute the flecking I use Cinnamon that weakens the colour and is beneficial in removing flecking. Unfortunately the Fallow gene is very weak and it is difficult to keep it balanced.

FM: The best way is to obtain Fallows from an exhibition stud, Fallows that have been bred by accident without previous knowledge of the genetic makeup of the parents.

We acquired our first pair of Fallows from a pet shop. I regularly visit the pet shops in town and one day I saw for the first time five German Fallows. The overall quality of the birds was miserable. The birds were small and flighty. In addition they were housed together with Agapornis and Cockatiels and most of the budgerigars had missing toes and were crippled. As Christmas day was close I nevertheless bought two German Fallows out of curiosity: A cock in Opaline Violet and a hen in Cobalt. Today we believe that it was a very good present as one year later we already enjoyed 30 budgerigars split for Fallow in our aviary. The Fallow cock paired to an Opaline Cobalt hen split Dilute raised 8 chicks and the Fallow hen paired to a blue cock that was split for Opaline raised 22 chicks in 3 rounds. A feature of the hen we particularly liked was the merit that she only stopped laying eggs when the first chick had hatched. Therefore clutch sizes have varied between 9 (first round) and 13 (second round). The maximal number of chicks raised was 9 (second round). We decided to stop breeding after three rounds even though the birds were still in excellent condition. We kept all the split Fallows for at least one year to select the best for future breeding and the 22 chicks have been used to evaluate the inheritance of physical features. The length of all birds, including the parents, was measured and plotted onto a graph. We anticipated that the length of the birds would be normally distributed. The size of the cock was 24cm compared to the 21cm of the hen. At this stage we only took into account the size of the birds ignoring their exhibition qualities. The cock was a good exhibition bird compared to the pet type hen.

The mean size of the offspring was 20.3cm with a standard deviation of 1.4cm (see below). The type of the chicks was not improved as they looked like their mother (small, thin, narrow face, small spots).



We concluded from these observations that most of the traits that define the size (and probably also other exhibition features) are not dominant at all.

The strategy described below we used to improve our Fallows is a logical consequence of these observations and may be applied to all recessive traits. We want to keep the characteristics, such as fertility, that are often related to small birds and we aim to introduce the required exhibition features as well.


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