Blue Andalusian

Blue Andalusian chickens are a classic example used to teach students about genetics!

The Blue Andalusian is a rare chicken that has struggled due to the challenges associated with breeding it for the desired deep, slate-blue color. Contrary to the name, not all Blue Andalusians are actually blue. Some are black, and others are a color known as splash, which is mostly white with splashes of black or blue. Breeders desire only the blue variety as show birds. These chickens made it off the Livestock Conservancy’s threatened list briefly in 2016, but were added back to the list after the 2021 census. They are active, curious birds that love to forage and run about. Although they are good egg layers, they are currently bred mostly for exhibition.

Incredible Blue Andalusian Facts

• Blue Andalusian chickens are known for their slate blue color, but some individuals are black and others are splash, or nearly white.
• These chickens are a classic example of incomplete dominance, much like Mendel’s famous pea plants.
• When breeding Blue Andalusians, a black parent crossed with a splash parent will produce all blue offspring.
• A blue parent crossed with another blue parent will produce offspring in a ratio of 1:2:1 – one black, to two blue, to one splash.
• Blue Andalusian chickens were originally exported from Andalusia, an autonomous community in southern Spain.
• Blue Andalusians are fast runners and they excel at flying, making them more resistant to predators than many other breeds.

Where to Find Blue Andalusian Chickens

Blue Andalusian chickens were first developed in Spain. They were first exported from Andalusia, the most southern autonomous community of peninsular Spain. The autonomous communities of Spain are somewhat similar to states or provinces, except that the government of the nation is less federalized than many other countries. No one knows precisely who first bred Blue Andalusian chickens in Spain, but they are a breed that has existed for centuries.

Blue Andalusians belong to the group of Mediterranean chickens that includes such breeds as the familiar Leghorn, the Minorca, the Catalana, the Ancona, and more. The Mediterranean chickens are native primarily to Spain and Italy. They were bred there for centuries before being exported to other parts of the world.

Blue Andalusian chickens were exported to England beginning in 1846 and continuing through the 1850s, when breeders there began to improve upon the blue coloring of these chickens. English breeders are credited with introducing the blue-laced coloration familiar today. By the mid-1850s, Blue Andalusians were imported to the United States, where breeders continued to enhance and refine the blue color of the breed. They were later exported to South America and Australia.

Scientific Name

The scientific name of the Blue Andalusian chicken is the same as other domestic chickens around the world. Gallus gallus domesticus, the modern domestic chicken, is a descendant of the red jungle fowl of Southeast Asia.

The common name of this breed is derived from Andalusia, the area of Spain from which it was first exported. Andalusia is the southernmost contiguous autonomous community in Spain. Although the breed is known as Blue Andalusian, only part of the population has the blue coloration for which it is named. Some are black, and others are mostly white, due to genetic influences on feather colors.

Appearance

Blue Andalusian chickens come in three colors: black, blue, and splash. The splash variation is nearly white, with irregular splashes of slate-blue or black throughout its plumage. Depending on the color of the parents, the probability of the offspring being blue, black, or splash can be pretty easily determined. To fully understand how this bird inherits its coloration, one must understand a little bit about genetics. Don’t worry, we’ll keep this to the most basic level.

You may remember learning about Gregor Mendel and his famous pea plants in a high school science class. In Mendel’s experiments, when pea plants with red flowers were bred with pea plants with white flowers, the resulting plants all had pink flowers. This is called incomplete dominance, meaning that neither the red gene nor the white gene was completely dominant over the other, so the offspring all had a color somewhere in the middle. The same thing happens with Blue Andalusian chickens.

Believe it or not, all Blue Andalusian chickens are genetically black, regardless of the color they show. However, like many other animals, this breed also has a gene known as a dilution gene, which causes the pigment to fade out. The chickens with two copies of this dilution gene are nearly white. The ones with no copies of the dilution gene have fully pigmented black feathers. And the ones with only one copy are in between, with partially diluted pigment, resulting in the slate-blue color for which the breed is named. The actual genetics are a little more complicated, but that’s the basic premise. We’ll take a closer look at how breeders get the desired blue plumage in the reproduction section below.

Other Characteristics

Blue Andalusian chickens are small to medium-sized chickens, with hens weighing about 5.5 pounds and roosters about 7 pounds. They stand anywhere from about 10 to 28 inches tall, and they have a long, slender, upright build, sometimes described as active or athletic. Males have long and flowing tail feathers. They also have long hackles which are black, or nearly so, in both the black and blue color varieties.

Both sexes have white, oval-shaped earlobes. Male earlobes are much larger than those of females. Their combs and wattles are bright red, and can flop over a bit, especially in females. Roosters have single combs that generally stand up straight and have five distinct points. These chickens have bone-colored beaks that curve downward, and dark gray, bare legs and feet, with long, straight toes.

Blue Andalusian Behavior

Descriptions of Blue Andalusian chickens sound remarkably similar to those of a cat. These chickens are reportedly intelligent and naturally curious, but also independent and aloof. They are generally tolerant of people, but they want their space. Blue Andalusians may bully other breeds and establish their dominance in a mixed flock.

These chickens are very active and good at foraging, but they do not tolerate confinement well. Confined birds may show their distress by picking at their own feathers and making a lot of noise. They are much happier ranging freely. They run very fast, and they fly well enough that even tall fences aren’t likely to keep them in. This does help protect them from predators, though. As long as they have branches or high perches, they can escape most attacks.

Some owners describe this breed as quite noisy, while others insist that they are not so bad. All in all, they are a relatively easy breed to raise, even though breeding them for show quality color and lacing can be complicated.

Diet

Blue Andalusian chickens are omnivores, and they are particularly good at foraging. They are active, fast-moving birds that love to range freely and hunt for food. Invertebrates such as insects, larvae, and worms are easy prey, and they are likely to catch small animals such as mice and lizards, too. They also eat seeds, green plant parts, and other vegetation.

Owners should supplement their flock with high-quality commercial feed with plenty of protein and calcium. They should also feed the chickens leafy greens and other fruits and vegetables, and even treats like pasta, rice, and bits of meat.   

Reproduction

Blue Andalusian chickens produce between 160 and 200 white eggs each year. They lay well even during cold weather, although they rarely go broody. Most breeders rely on incubators to hatch chicks. Males reach sexual maturity at around seven weeks of age. Females begin laying eggs as early as five to six months.

Potential breeders should familiarize themselves with how the coloration of these chickens is produced. It all comes down to reproduction and genes. First, the genotype is the actual combination of genes that the chicken possesses. And the phenotype is the physical characteristic that is expressed by those genes. In Blue Andalusians, the splash phenotype, which is mostly white, has two genes for color dilution. Let’s represent that as bb. The black phenotype has two genes for no dilution, which we can represent as BB. The blue color is the desired phenotype, and the genotype associated with it is a combination of one gene for dilution of color and another gene for no dilution. We can represent this combination as Bb. 

When a black bird is bred to a black bird, represented as BB x BB, the resulting offspring will all have a BB genotype and black coloring. Likewise, when a splash bird is bred to a splash bird, represented as bb x bb, the resulting birds will all have a bb genotype and will all be splash colored. However, when a splash bird is bred to a black bird, represented as bb x BB, the resulting offspring will each get one b from the splash parent and one B from the black parent. Therefore, they will all have the genotype, Bb. And because of incomplete dominance in this trait, these individuals will be neither black nor white, but blue in color.

Blue x Blue

In Blue Andalusians, it gets really interesting when blue birds are bred to other blue birds. Knowing that the blue variety has a genotype of Bb, this cross would be represented as Bb x Bb. In this case, each offspring could get either a B gene or a b gene from the mother, and a B gene or a b gene from the father. Statistically, crosses of this type result in offspring that are black, blue, and splash in a 1:2:1 ratio. Approximately 25 percent of the offspring will have a BB genotype and present as black. Another 25 percent will have a bb genotype and present as splash. The remaining 50 percent will be Bb, and will present as blue. 

Of course, there are even more factors to consider when breeding the birds, including how to enhance and preserve the lacing pattern and how to deepen the blue color. Those endeavors require deeper knowledge than this article will address.

Predators

Because Blue Andalusian chickens do not do well in confinement, many owners allow them to free range. As such, they may be more vulnerable to predators like hawks, owls, and eagles. Ground predators such as foxes, weasels, and raccoons may be less dangerous to these chickens than to heavier breeds, such as the Brahma chicken or the Cochin chicken, because Blue Andalusians are light and very good at flying up to branches. Nest predators, such as snakes, can pose a threat if coops are not well secured.  

Lifespan & Conservation

Blue Andalusian chickens can live an average of 5 to 8 years. This breed is considered rare, with fewer than 5,000 birds worldwide. It was moved up from the threatened category to watch status by the Livestock Conservancy in 2016. However, the breed was moved back to threatened after the 2021 census, along with many others. Although Blue Andalusians are good egg layers, they are complicated to breed and are not nearly as favored for production as the Leghorn chicken. Still, there is interest in this active bird, and hope for a resurgence in interest among small breeders.

1. William A. Lippincott, Available here: https://www.journals.uchicago.edu/doi/pdf/10.1086/279658
2. The Livestock Conservancy, Available here: https://livestockconservancy.org/wp-content/uploads/2022/10/2022-cpl.pdf