English Fallow Budgerigar Mutation, Complete Genetics Guide

English Fallow originated in England in 1937 as the second documented Fallow mutation in budgerigars. It is also called Pale Fallow, a name proposed by Inte Onsman of MUTAVI Research, and occasionally Dun Fallow. The defining visual is the solid red eye with no visible iris ring, contrasting sharply with the white iris ring of German Fallow. Body suffusion is paler than the German variant. Autosomal recessive at its own dedicated locus.

Written by Ayaan Shohan

Founder, KinBird Aviary · Bangladesh

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What English Fallow looks like on a real bird

English Fallow shares the warm bronze body palette of all Fallow types but expresses it more lightly. The body suffusion is a paler brown than German Fallow, often described as a soft beige-bronze rather than the deep bronze of the German line.

The defining feature is the eye. Unlike German Fallow, English Fallow shows a solid red eye in which the iris ring is so faint as to be barely discernible. Look at a mature English Fallow under good light and the pupil seems to blend straight into the red iris with no white edge to define it.

Wing markings are diluted to a soft brown, and on blue-series birds the body comes out a pearly bronze with a hint of pale blue underneath. Yellow Face English Fallow keeps the face yellow but tones down the body further still.

History and origin

English Fallow appeared in 1937 in England, eight years after Schrapel established the German Fallow line. The English mutation arose independently and was confirmed to be non-allelic with German Fallow through test pairings carried out by British breeders during the late 1930s and 1940s.

The variant gained the alternative name Pale Fallow in the 1990s and 2000s when Dutch geneticist Inte Onsman of MUTAVI Research proposed adopting the descriptor Pale Fallow as a more accurate phenotypic name. Some breeders informally call the same mutation Dun Fallow because of the muted dun-grey wash on blue-series birds. The Wikipedia entry for the mutation acknowledges all three names: English Fallow, Pale Fallow, and Dun Fallow refer to the same gene.

The English line was always smaller than the German line. By the 1960s the population had stabilized but remained niche. Today serious Fallow breeders maintain English Fallow primarily for collection completeness and for the specific aesthetic of the lighter bronze body.

How English Fallow inheritance works

English Fallow is autosomal recessive. The gene sits at its own dedicated locus, separate from German Fallow and Scottish Fallow. Allele symbol: pf-e.

Inheritance follows standard autosomal recessive rules. A bird needs two copies of the English Fallow gene (pf-e/pf-e) to visually express the mutation. One copy paired with a Normal allele (+/pf-e) produces a split bird that looks entirely Normal but carries the gene.

The most common misconception is treating English Fallow as allelic to German or Scottish Fallow. It is not. Each Fallow type lives on a different chromosome at a different locus. The implication is straightforward but counter-intuitive for new breeders: a visible English Fallow paired with a visible German Fallow produces 100 percent Normal-looking chicks, every chick split for both genes but visually Normal because neither gene has its required pair of recessive alleles.

A visible English Fallow paired with another visible English Fallow always produces 100 percent visible English Fallow chicks. A visible English Fallow paired with a Normal bird produces 100 percent Normal-looking chicks all split for English Fallow.

Pairing predictions for English Fallow

Same-locus pairings (English Fallow x English Fallow):

Visual English Fallow x Visual English Fallow gives 100 percent Visual English Fallow.

Visual English Fallow x Split English Fallow gives 50 percent Visual English Fallow and 50 percent Split English Fallow.

Split English Fallow x Split English Fallow gives 25 percent Visual English Fallow, 50 percent Split English Fallow, and 25 percent Normal birds with no Fallow gene at all.

Visual English Fallow x Normal (with no Fallow gene) gives 100 percent Split English Fallow.

Cross-Fallow pairings (English Fallow with German or Scottish Fallow):

Visual English Fallow x Visual German Fallow gives 100 percent Normal-looking offspring all split for both genes. None of the offspring are visually Fallow because neither gene has both required recessive copies.

This cross-Fallow trap catches new breeders every year. The visual outcome is identical to pairing two unrelated Normals, which makes the breeder think their Fallows are not working. The reality is that the genes simply do not interact at the same locus.

A dedicated breeder who pairs cross-Fallow specifically to produce split-both stock can use those split-both birds in a second generation. Pairing two split-both birds together produces a 1 in 16 chance of a chick that is visual for BOTH Fallow types simultaneously, the so-called Double Fallow that combines features of two variants. This is a long-term project and few breeders maintain it.

Combinations with other mutations

English Fallow combines with all major budgerigar mutations because the gene is autosomal recessive and does not compete with sex-linked or incompletely dominant genes for any shared locus.

English Fallow Opaline produces a paler bronze body with the wing-reversal Opaline pattern, lighter overall than German Fallow Opaline. English Fallow Cinnamon adds the brown wing pattern on top of the already-pale body, producing one of the softest looking combinations in budgerigar genetics. English Fallow Spangle combines the reverse markings of Spangle with the pearly Fallow body.

English Fallow Recessive Pied produces an irregular pied pattern over the pale bronze body, popular in pet stock. English Fallow with the dark factor stack (Cobalt or Mauve on blue series, Dark or Olive Green on green series) deepens the body suffusion proportionally.

As with all Fallow variants, English Fallow paired with visual Ino (Lutino or Albino) produces a bird that visually appears Lutino or Albino because the Ino gene removes the melanin that gives Fallow its bronze body. The Fallow gene is present but hidden behind the Ino phenotype.

Distinguishing English Fallow from German and Scottish Fallow

The reliable diagnostic feature is the eye iris.

English Fallow shows a solid red eye with no visible iris ring or a barely discernible iris. Look at the pupil under direct light. If the red iris blends straight into the pupil with no white edge to define it, you are looking at English Fallow.

German Fallow shows a clearly visible white iris ring around the pupil at maturity. The white edge is sharp and unmistakable in good light.

Scottish Fallow shows a pink iris instead of red. The pink colour is genuinely pink, not a pale red, and it stays pink under any lighting condition.

Body suffusion is a secondary clue but less reliable than the iris because lighting and feather condition can shift apparent colour. The order from deepest to palest body is German Fallow first, then English Fallow, then Scottish Fallow.

When identification is uncertain on a single bird, test-pair the unknown to a confirmed visual English Fallow. If all chicks are visual English Fallow, the unknown was English Fallow. If all chicks are Normal-looking, the unknown was German or Scottish Fallow at a non-matching locus.

Why English Fallow is sometimes called Pale Fallow or Dun Fallow

The English Fallow mutation has accumulated three commonly used names: English Fallow (country of origin), Pale Fallow (proposed by Inte Onsman of MUTAVI Research), and Dun Fallow (a vernacular descriptor based on the muted dun-grey wash on blue-series birds).

Inte Onsman proposed Pale Fallow in his MUTAVI Research notes as a more phenotypically descriptive name. His reasoning: country-of-origin names obscure the underlying genetics, while phenotypic names tell the breeder what to look for. Pale Fallow correctly indicates the lighter body compared to German Fallow.

Dun Fallow is older vernacular and appears in some Australian and South African breeder circles, particularly when describing the mutation on blue-series birds where the dun-grey wash is most visible.

For international communication, English Fallow remains the safest name because it is recognized in WBO judging standards, the Wikipedia entry, and Terry Martin's 2002 reference. Pale Fallow is increasingly used in academic genetics literature, and Dun Fallow persists in regional hobby circles.

English Fallow in the Budgerigar Genetics Calculator

The Budgerigar Genetics Calculator at budgerigargenetics.com treats English Fallow as a standalone autosomal recessive mutation with its own dedicated entry. The engine handles English Fallow as non-allelic with German Fallow and Scottish Fallow, which means cross-Fallow pairings produce the genetically correct Normal-looking split-both offspring.

Select English Fallow as a mutation on either parent and set the status to Visual or Split. The calculator outputs offspring percentages with proper autosomal recessive segregation and correctly handles combinations with all other budgerigar mutations.

Try the canonical pairings: Visual English Fallow x Visual English Fallow for 100 percent visual offspring, or Cross-Fallow English x German to see the all-Normal split-both result that catches new breeders.

Frequently asked questions about english fallow

What is the English Fallow budgerigar mutation?

English Fallow is an autosomal recessive budgerigar mutation that produces a pale bronze body suffusion and solid red eyes with no visible iris ring. Established in England in 1937, it is the second of three documented Fallow mutations in budgerigars. Also known as Pale Fallow (proposed by Inte Onsman, MUTAVI Research) or Dun Fallow. Allele symbol: pf-e.

Is English Fallow the same as Pale Fallow or Dun Fallow?

Yes, all three names refer to the same mutation. English Fallow is the country-of-origin name. Pale Fallow was proposed by Inte Onsman of MUTAVI Research as a more phenotypically descriptive name. Dun Fallow is an older vernacular term used in some Australian and South African breeder circles. The Wikipedia entry for English Fallow lists all three names. For international clarity, English Fallow remains the most widely recognized.

How do I tell English Fallow apart from German Fallow?

The iris is the reliable diagnostic. English Fallow has solid red eyes with barely discernible or no visible iris ring. German Fallow has red eyes WITH a clearly visible white iris ring around the pupil. Body colour is a secondary clue: English Fallow body is noticeably paler than German Fallow. Under uncertain conditions, test-pairing to a confirmed visual English Fallow always resolves identification, because matching-locus pairings produce 100 percent visual offspring.

Why does pairing English Fallow with German Fallow not produce Fallow chicks?

Because English Fallow and German Fallow are at different loci, they are non-allelic mutations. Each Fallow gene needs its own homozygous pair to express visually. An English Fallow x German Fallow cross gives each chick one copy of each gene, but not a homozygous pair of either. The chicks are split for both genes but visually Normal. This is the most common Fallow breeding mistake. The Budgerigar Genetics Calculator models this correctly so you can verify before pairing.

Can a hen be split for English Fallow?

Yes. English Fallow is autosomal recessive at an autosomal locus, so cocks and hens inherit identically. A hen carrying one copy of pf-e (+/pf-e) looks entirely Normal but passes the gene to roughly half of her offspring. Both cocks and hens are equally useful as splits in any English Fallow breeding programme.

What does Split English Fallow x Split English Fallow produce?

25 percent Visual English Fallow, 50 percent Split English Fallow, and 25 percent Normal birds with no Fallow gene at all. This is the textbook autosomal recessive 1:2:1 ratio. The 25 percent visible offspring are guaranteed to breed true, the 50 percent split offspring carry the gene invisibly, and the 25 percent gene-free Normals cannot be distinguished from the splits by sight alone.

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