Aqua Mutation in Lovebirds:
Aqua B1, Aqua B2 and Aqua Homozygote Explained

What is the Aqua mutation?

The aqua mutation in lovebirds is an allele of the blue (bl) locus that partially reduces psittacine pigment by about 50 percent, turning the normal green body a turquoise, sea-green "aquamarine" shade, and softening the orange face mask to light pink. It has three visual forms: Aqua Homo (aqua / aqua), which is autosomal recessive, plus Aqua B1 (aqua // bl1) and Aqua B2 (aqua // bl2), which are co-dominant compounds with the blue-series alleles.

Aqua is a mutation that partially modifies the expression of the colour pigment pathway in Agapornis fischeri, producing a turquoise or sea-green body colour instead of normal green. The result is a bird that sits visually between a normal green and a full blue, a clear turquoise that catches light differently from either.

Aqua is distinct from the Blue alleles at the same locus (which eliminate psittacine pigment and produce a pure blue bird). Aqua birds retain part of the psittacine pigment, producing the characteristic teal-turquoise tone. The orange face mask fades toward light pink for the same reason.

Aqua Homo (aqua / aqua) is autosomal recessive, both males and females can be carriers, and two aqua alleles are needed for the fully recessive visual. Aqua B1 (aqua // bl1) and Aqua B2 (aqua // bl2) are co-dominant compounds, two different blue-locus alleles that co-express instead of one masking the other, which is why a single aqua allele is visible when the allele opposite it is bl1 or bl2 rather than wild-type green.

How the aqua mutation works, in plain terms

A normal green lovebird gets its colour from two things layered together: a structural blue produced inside the feather, and a yellow pigment (psittacine) sitting over it. Blue light passing through a yellow filter reads as green (Dyck, 1971).

• The Blue mutation removes all of the yellow pigment. With the yellow filter gone, only the structural blue is left, so the bird is pure blue.
• The Aqua mutation removes only about half the yellow pigment (roughly a 50 percent psittacine reduction). The bird lands between green and blue, the turquoise "aquamarine" colour, and the orange-red mask fades toward pink for the same reason (Van den Abeele, Lovebird Compendium, pp. 298 to 303).

That is why aqua is called a partial blue, or a PPR mutation (Partial Psittacine Reduction). It is not a different pigment, it is the same green machinery with the yellow turned down halfway.

Seagreen and AquaTurquoise: aqua combined with turquoise

Turquoise is a second partial-blue allele on the same locus, but it cuts psittacine harder, around 90 percent on the body. Pair aqua with turquoise and you get a bird historically listed as "seagreen" (or apple-green in peach-faced). It is not a separate mutation, it is two blue-locus alleles paired as a compound, correctly written Aqua // Turquoise (Van den Abeele, Ornitho-Genetics VZW, 2014).

The three Aqua types

Aqua, blue type 1 (bl1) and blue type 2 (bl2) are all alleles of one gene, the blue (bl) locus, and a bird carries at most two of them. Which two it carries determines which Aqua type it is. Throughout this article a single slash means a split (Green / Aqua) and a double slash means an allelic compound, two different alleles of the same gene that both express (aqua // bl1):

Splits and carriers

Aqua is recessive to wild-type green, so it can be carried hidden in the green series. A green bird carrying a single aqua allele looks completely normal, green with no turquoise visible. The aqua allele is there but needs a second blue-locus mutant allele before anything shows.

A green carrier is written as Green / Aqua. There is no such bird as "Green / Aqua B1", because B1 names the second allele at the same locus, and a green bird already carries wild-type green there. Green carriers are sought-after breeding stock because, when paired with another Aqua carrier or an Aqua visual, they produce Aqua offspring.

To confirm split status: test pair with a visual Aqua. If any turquoise offspring appear, the bird is confirmed to carry the allele. DNA testing is also available for earlier confirmation.

Core Aqua pairings

These are the most important pairings for Aqua production. The calculator handles all combinations, including multi-trait pairings that include Opaline, Pale Fallow, or other mutations alongside Aqua.

Complete Aqua pairing reference table

All key Aqua pairings in one place. These ratios apply symmetrically to both B1 and B2 alleles, substitute B2 for B1 in any same-allele pairing and the percentages are identical. For multi-trait pairings (Aqua + Opaline, Aqua + Pale Fallow, Aqua + Yellow Face), use the genetics calculator.

* Neither parent in a visual × visual pairing carries a wild-type green allele, so this final quarter is a visual blue-series bird, Blue 1 (bl1 / bl1) or Blue 2 (bl2 / bl2), not a green bird. In the Aqua B1 × Aqua B2 row the 75% visual splits into 25% Aqua B1, 25% Aqua B2 and 25% Parblue (bl1 // bl2), and Aqua Homo is fully possible because both parents carry the aqua allele (see Pairing 6).

How to select quality Aqua breeding stock

Good Aqua breeding stock is judged on two things at once: confirmed genotype and physical quality. The genotype tells you what a bird can produce, while feather condition, body weight, and eye colour tell you whether it can raise those offspring reliably. A visually stunning Aqua Homo with poor fertility is a weaker founder than a slightly plainer bird that breeds dependably.

Start with genotype, because it is the part you cannot see. The single most useful confirmation for an Aqua bird is whether it is truly Homo (aqua / aqua) or only a single-aqua compound, aqua // bl1 or aqua // bl2. A confirmed Homo passes Aqua to every chick and never wastes a slot on a pure normal, which is why experienced breeders insist on a documented pedigree or a test pairing rather than relying on body colour alone. The same care applies to the allele sitting opposite the aqua: a bird should be known as Aqua B1 or Aqua B2, never assumed, because that second allele decides whether the quarter of the nest that misses out on aqua comes out as Blue 1, Blue 2 or Parblue (see Pairing 6). Treat any "Aqua" bird of unknown allele pairing and unknown zygosity as a question mark until records or a test cross resolve it.

Once genotype is settled, select on physical quality. Look for tight, well-aligned feathering with no persistent fret marks, a bird of good size and weight for its age, clean nostrils and bright clear eyes, and steady, alert behaviour at the nest. For Aqua specifically, the depth and evenness of the turquoise across the rump and back is the most reliable visual cue separating a strong Homo from a paler single-allele bird in fresh plumage. Avoid founders from tightly inbred single-source lines: years of Aqua x Aqua pairing without outcrossing can quietly erode fertility and chick survival, and that weakness compounds across the generations you are about to build.

Finally, think in terms of pairs rather than individuals. The fastest route to a stable Aqua Homo line is to retain several confirmed B1 splits or visuals from a single strong clutch, so that you can pair like with like and steadily concentrate the allele. Selecting one excellent bird is a start; selecting a matched group is what lets you reach the Homo x Homo end state in two to three seasons.

Sourcing Aqua Lovebirds

Aqua is one of the most widely worked mutations in Fischer's lovebirds across South and Southeast Asia. Knowing where reliable Aqua Homo stock comes from, and how to confirm it, is essential for any breeder working seriously with this mutation.

Sourcing from Indonesia and the Philippines

Indonesia is the world's largest Fischer's lovebird producer and the origin of most widely traded Aqua Homo lines. The Philippines hosts several established Aqua Homo and Aqua Homo Opaline operations. When importing from either country:

• Confirm the allele pairing first, request clarification on Aqua B1, Aqua B2 or Aqua Homo before acquiring the bird. Aqua B1 × Aqua B2 still yields Aqua Homo at 25 percent (see Pairing 6), but the rest of the nest comes out as Aqua B1, Aqua B2 and Parblue rather than as a single predictable type, so records matter.
• Request breeding records, visual confirmation of Homo vs. B1 is unreliable from photos and video. Parent-pair records with clutch outcome data are the minimum standard for any serious acquisition.
• DNA testing, available from specialist avian genetics labs. Definitive: confirms allele type, split status, and sex simultaneously. Strongly recommended for any acquisition where Homo status matters.
• Test pair on arrival, pair the acquired bird with a confirmed Green (no Aqua). A true Homo produces 100% green-looking splits, zero visual Aqua chicks. To separate a Homo from a single-aqua Aqua B1 or Aqua B2, pair instead to a confirmed Aqua Homo: two Homo birds give 100% Aqua Homo, while a single-aqua bird throws lighter Aqua B1 or Aqua B2 chicks alongside the Homo ones.

Aqua combined with other mutations

Aqua's real breeder demand explodes in combination with other mutations. The turquoise base colour interacts with every other mutation, producing birds that are among the most visually striking in the lovebird world:

• Aqua Homo Opaline female, the Opaline redistribution enhances the turquoise, producing a deeply saturated, gradient-rich bird. Among the most sought-after combinations globally.
• Aqua Pale Fallow, the Pale Fallow melanin reduction softens the Aqua turquoise to a pastel teal. A very different look from either mutation alone. Full pairing breakdown: Aqua Homo × Pale Fallow →
• Aqua Yellow Face, Yellow Face on an Aqua base produces a unique warm-toned turquoise, different from standard Aqua.
• Aqua Cinnamon, Cinnamon's warm melanin reduction on the Aqua base creates a distinctive cinnamon-tinted teal.

Combined Aqua mutations follow independent assortment, each mutation's Mendelian ratios apply separately. Model any combination at once in the calculator.

Aqua vs Parblue, they are different

Parblue is the allelic compound bl1 // bl2, a bird carrying blue type 1 on one chromosome and blue type 2 on the other. Aqua is not a different mutation from Parblue, both are combinations at the same blue (bl) locus, they simply use different pairs of alleles from that one allelic series. Because the two combinations sit on the same locus they produce birds with similar turquoise coloration, which causes significant confusion in the trade, especially when birds are imported without documentation.

The B1 vs B2 vs Aqua Distinction: Clearing Up the Confusion

Many Fischer's lovebird breeders confuse the terms Aqua, B1, and B2, using them interchangeably when they refer to distinct genetic states. Getting this right matters enormously for breeding strategy and demand.

Aqua B1, the aqua // bl1 compound

Aqua B1 is a bird carrying the aqua allele on one chromosome and the blue type 1 (bl1) allele on the other, written aqua // bl1. Both alleles belong to the blue (bl) locus and they co-express rather than one masking the other, which is why a single aqua allele is visible here: the bird reads as a light-to-mid turquoise. That is co-dominant expression at the bl-locus, not a partly penetrant recessive. Reserve the name "Aqua B1" for that visible compound. A bird carrying aqua on one chromosome and the wild-type green allele on the other is not an Aqua B1, it is a green-looking carrier written Green / Aqua.

bl2 and Aqua B2, the second blue-series allele

bl2, blue type 2, is another allele at the same blue (bl) locus. A bird with bl2 / bl2 is a visual Blue 2, and a bird with bl1 / bl1 is a visual Blue 1. Put the aqua allele opposite bl2 and you get Aqua B2 (aqua // bl2), the second co-dominant turquoise compound. Aqua Homo is neither of these: it is aqua / aqua, two copies of the aqua allele, and it is the fully autosomal recessive form. Because every one of these alleles occupies the same position, a bird carries at most two of them.

Parblue, the bl1 // bl2 compound

A bird with one bl1 allele and one bl2 allele (bl1 // bl2) is a Parblue, the turquoise allelic compound. Parblue birds show a distinctive yellowish or cream face mask, and their body turquoise is slightly lighter than Aqua Homo. This yellowish-face feature is what separates Parblue from Aqua Homo and from standard Blue. Note that Parblue carries no aqua allele at all, so it cannot pass one on.

The key rule: alleles are exclusive

A bird cannot carry aqua, bl1 and bl2 all at once. Each chromosome carries one allele at the locus, so two slots in total, and the two alleles, one from each parent, replace each other at the same position. "Aqua" in the Fischer's hobby usually means aqua / aqua Aqua Homo unless otherwise specified. For the full blue-series deep dive, see our Blue lovebird genetics article.

What Aqua Homo Looks Like vs Aqua Split vs Parblue

Visual identification is one of the most frequently asked questions in Aqua breeding. The four phenotypes are distinct but require experience to reliably separate.

Aqua Homo (aqua / aqua), the deepest turquoise

The Aqua Homo bird shows a fully saturated teal-green across the entire body. The turquoise produced by two aqua alleles is noticeably richer and deeper than any single-aqua compound. The face mask is not left untouched: the same partial psittacofulvin reduction that turns the body turquoise also fades the orange-red mask toward light pink, which is exactly what the Compendium records. The rump and back feathers are where the deepest colour concentrates, and experienced breeders use the rump colouring as their primary visual diagnostic when assessing Aqua birds at fledging. The body colour is clearly turquoise even to non-experts who have never seen the mutation before.

Green / Aqua, the split that looks completely normal green

A bird that carries one aqua allele and one normal (wild-type) allele looks completely normal green. There is zero visual difference between an Aqua split and a non-carrier normal. This is critical to understand: when you pair an Aqua Homo with a pure Green, every single offspring will be a Green / Aqua split that looks perfectly normal. These birds are confirmed carriers and should never be discarded or passed on as "pure normals." They are the foundation of your next generation of Aqua production. Confirmation requires pedigree records, test pairings, or DNA testing.

Parblue (bl1 // bl2), the yellowish face diagnostic

The Parblue bird (bl1 from one parent, bl2 from the other) shows a turquoise body that is lighter than Aqua Homo. The key diagnostic feature is the face mask: Parblue birds show a yellowish or cream tint on the face, where an Aqua bird's mask fades toward light pink and a normal green Fischer's stays orange-red. That yellow cast is the single most reliable visual separator between Parblue and both Aqua Homo and standard Blue. The body turquoise itself is ambiguous, lighting conditions and individual variation make body colour alone an unreliable diagnostic, but the face mask is consistent.

Green / Aqua one-copy carriers, the "split"

As covered above: completely normal green appearance. The split status can only be confirmed by breeding outcome or DNA test. Never assume a green bird from a known Aqua parent is a non-carrier, it may well be carrying the allele that will produce your next Aqua Homo.

Aqua Homo Breeding Programme, Generation by Generation

Building an established Aqua Homo line takes discipline and record-keeping over multiple seasons. Here is the generation-by-generation roadmap.

Starting with one Aqua Homo male

If you acquire a confirmed Aqua Homo male, pair him with any normal female. The result is 100% Green / Aqua splits in Generation 1, every chick looks normal green but carries the aqua allele. This is not a wasted generation. These confirmed splits are your next season's foundation breeders. Keep all females as confirmed split females, and keep the best split males for back-pairing.

Generation 2: split × split producing Homo

Pair two confirmed Green / Aqua splits together. The offspring ratio is: 25% Aqua Homo visual, 50% Green / Aqua split, 25% normal non-carrier. From a single pair producing 4 to 6 chicks per clutch over 2 to 3 clutches in a season, you should statistically produce 1 to 2 Homo birds in this generation. Band all chicks from these pairings carefully, and do not part with any before confirming Homo vs. split status.

Consolidating: Aqua Homo × Aqua Homo

Once you have a confirmed Homo male and a confirmed Homo female (aqua / aqua × aqua / aqua), every single offspring from that pair will be Aqua Homo. This is the ideal established line state, 100% sought-after production per clutch, zero splits, zero normals. Getting to this point typically requires 2-3 seasons starting from your first Homo bird.

Introducing a second mutation into the Aqua Homo line

Adding Opaline or Pale Fallow to an Aqua Homo line is a multi-season project. You cannot introduce Opaline simply by pairing an Aqua Homo male with an Opaline female, the Opaline is sex-linked, and the Aqua is autosomal recessive, so the combinations require careful planning. The fastest route is to obtain a male that is Aqua Homo and split Opaline simultaneously (produced by pairing an Aqua Homo male with an Opaline female in a prior generation, then selecting the appropriate male offspring). This takes 2 or more additional seasons beyond establishing the Homo line. See the Aqua Homo × Pale Fallow pairing guide for the popular combination breakdown.

History and Origin of the Aqua Mutation

The aqua mutation first appeared in the early 1960s in the Netherlands, in the peach-faced lovebird (Agapornis roseicollis). The Lovebird Compendium records the first appearance in 1963, with Dutch breeder P. H. Habels of Roosendaal (Van den Abeele, 2016, pp. 298 to 303). It is the oldest of the partial-blue mutations in lovebirds.

Genetically, aqua is an allele of the blue (bl) locus and inherits autosomal recessive. It does not remove psittacine pigment completely the way the Blue mutation does. Instead it reduces it by roughly 50 percent across the whole plumage, producing the "aquamarine" colour between green and blue, with the red or orange mask fading to light pink and yellow areas turning paler. Because the reduction is partial, Van den Abeele classes aqua as a PPR mutation (Partial Psittacine Reduction), the lovebird equivalent of the budgerigar yellow-face.

The name changed over the decades. Before the international naming system, breeders used seagreen, seablue, ivory, pastel and pastel blue for these birds. The community settled on "aqua", short for aquamarine, to end the confusion (Van den Abeele, Ornitho-Genetics VZW, 2014).

Aqua in Fischer's lovebirds, the honest position. In A. roseicollis aqua is a confirmed, established mutation. In A. fischeri, aqua-looking phenotypes appear regularly, but Van den Abeele recorded that the early Fischer "aqua" birds behaved as modifications rather than a proven separate mutation, and later test-matings (confirmed 2018) showed Fischer's lovebirds carry two blue-series alleles, blue type 1 and blue type 2, whose combinations create the turquoise and aqua-type phenotypes on that same bl-locus. For a breeder this means the Fischer aqua, blue 1, blue 2 and parblue birds are all variations on one locus, which is exactly how this calculator models them.

Aqua should not be confused with turquoise, a separate PPR allele on the same locus. Turquoise reached A. roseicollis in the 1970s (first described in Belgium in 1967, originally called "pastel") and reduces psittacine far more, about 90 percent on the body, which is why it often reads almost blue. In Fischer's lovebirds the turquoise look is frequently listed as "yellow face". See our Blue, Blue 2 and Parblue genetics guide and the Yellow Face guide for how these alleles interact.

Common Mistakes with Aqua Birds

Mislabelling Parblue as "Aqua"

The most common trade error: a Parblue bird (bl1 // bl2) is described as "Aqua" without clarification. Parblue and Aqua Homo are visually distinct, the face mask yellowing of Parblue is the key diagnostic, but breeders and keepers alike sometimes use "Aqua" as a catch-all for any turquoise bird. When you acquire a bird as Aqua Homo, check that the mask has faded toward light pink rather than carrying a yellow or cream cast. A yellow face on a turquoise bird means Parblue or Yellow Face Aqua, not Aqua Homo.

Treating a green split as a non-carrier

After producing Aqua offspring, breeders sometimes pass the green siblings on as "pure normals" without checking their split status. A green bird from a pair that produced any Aqua offspring is either a confirmed split or a non-carrier, and you need test pairings or DNA to know which. Labelling a confirmed or likely split as a non-carrier discards real genetic potential and misleads the next breeder. Always track the splits and record them accurately.

Assuming "Aqua × Aqua = 100% Aqua offspring"

This is only true if both parents are Aqua Homo (aqua / aqua). If one parent is a single-aqua Aqua B1 (aqua // bl1), the pairing is Homo × Aqua B1, which gives 50% Homo and 50% Aqua B1, still excellent, but not 100% Homo. If both parents are Aqua B1, the pairing gives 25% Homo, 50% Aqua B1, 25% Blue 1, a completely different distribution. Always know which of the three Aqua genotypes each parent is before predicting outcomes.

Confusing Aqua with Pale Fallow

Both mutations alter body colour. Pale Fallow produces a greenish or pastel bird with pink-red eyes. An Aqua bird, whether B1 visual or Homo, has completely normal dark brown eyes. If you see altered body colour plus red or pink eyes, you are looking at a fallow mutation, not Aqua. This confusion is common in birds that are double-mutation (Aqua + Pale Fallow), where the combination of both mutations produces an eye colour change alongside the turquoise body. On a single-mutation Aqua bird, eyes are always normal dark brown.

Identifying Aqua Homo in your nest

Experienced breeders who have worked with both types can often identify Homo offspring at fledging by the deeper, more saturated turquoise colouring, particularly noticeable on the rump and back, and in the blue wing coverts. In fresh plumage, the difference between a B1 visual and a Homo is clear to a trained eye.

If you are less experienced, the safest approach is to band all Aqua offspring separately and test-pair any you cannot confirm visually. Breeding a suspected Homo with a pure normal green gives a whole nest of green-looking confirmed splits and zero visual chicks, because the pure normal parent contributes a wild-type allele to every chick. That result tells you the bird carries aqua, but it does not on its own separate a Homo from an Aqua B1 or Aqua B2, since those also throw no visuals over pure Green. To confirm Homo, pair the bird to a known Aqua Homo: two Homo birds give 100% Aqua Homo, while a single-aqua compound throws lighter Aqua B1 or Aqua B2 chicks in the same nest.

Aqua pairing outcomes, cock × hen

Breeders usually describe a pairing as cock × hen. Below is every common Aqua pairing written that way, with the exact percentages this calculator produces.

Aqua cock × aqua hen

Every chick is a visual Aqua, cocks and hens alike. Because Aqua is autosomal recessive, sex plays no part in the outcome. This holds when both parents are Aqua Homo. If both parents are Aqua B1 instead, the blue locus splits 25% Aqua Homo, 50% Aqua B1 and 25% Blue 1, so a quarter of the clutch is not Aqua at all.

Aqua cock × normal hen

No visual chicks appear in this generation. Every chick is a normal-looking bird carrying one hidden copy, written as normal / Aqua.

Split aqua cock × split aqua hen

One quarter of the chicks are visual Aqua. Half are splits and one quarter carry nothing, and the splits and pure normals look identical.

Aqua cock × split aqua hen

Half the chicks are visual Aqua and half are splits, with the same result whichever parent carries the visible mutation.

Run any of these in the lovebird genetics calculator to see the full offspring list for your own birds.