Breeds

Sex-Link Chickens: Red vs Black Sex-Links, Parent Crosses and Color-Sexed Chicks

Field guide · Updated October 22, 2026 · about 8 min read

A sex-link is not a breed but a first-generation cross: a rooster of one breed mated to hens of another, chosen so that the chicks hatch in different colors by sex. Mississippi State Extension describes them as crossbred chickens whose color at hatching is differentiated by sex. The two common families are red sex-links (often sold as Red Stars) and black sex-links (Black Stars). This page sets out which crosses produce them, what the chicks look like, why the mating works only one way and what sources say about laying.

Red vs black sex-links at a glance

Trait	Red sex-link	Black sex-link
Rooster (sire)	Rhode Island Red or New Hampshire	Rhode Island Red or New Hampshire; any male without the barring or dominant white gene, such as a Black Australorp or Buff Orpington (Kentucky ASC-231)
Hen (dam)	White Plymouth Rock carrying the silver factor, Silver Laced Wyandotte, Rhode Island White or Delaware	Barred Plymouth Rock; Kentucky also names the Cuckoo Maran
Gene that does the sorting	Silver from the hen against gold from the rooster	Barring from the hen against a non-barred rooster
Male chicks	Hatch white	Black down with a white dot on the head
Female chicks	Hatch buff or red, depending on the cross	Black down, no head spot
Adult males	White, or white with some black	Barred, with a few red feathers
Adult hens	Buff or red	Solid black with some red in the neck
Egg shell	Brown	Brown; Cackle Hatchery lists light brown for its birds
Catalog names	Red Star, Gold Comet or Golden Comet (New Hampshire or Rhode Island Red × White Rock), Cinnamon Queen (New Hampshire × Silver Laced Wyandotte)	Black Star, Rock Red; Wikipedia also lists the Black Rock

Crosses, chick and adult colors are from the University of Kentucky's sex-linked crosses page and Mississippi State Extension; egg shell color from Poultry Extension (Jacquie Jacob, University of Kentucky).

Gold rooster: Rhode Island Red or New Hampshire
Silver hen: White Plymouth Rock carrying the silver factor, Silver Laced Wyandotte, Rhode Island White or Delaware
Red sex-link sons: hatch white; adults white or white with some black
Red sex-link daughters: hatch buff or red, depending on the cross; adults buff or red
Non-barred rooster: usually a Rhode Island Red or New Hampshire; Kentucky also names the Black Australorp and Buff Orpington, but not a male with the barring or dominant white gene
Barred hen: Barred Plymouth Rock (or Cuckoo Maran)
Black sex-link sons: black down with a white dot on the head; feather out barred with a few red feathers
Black sex-link daughters: black down, no dot; feather out solid black with some red in the neck
One way only: a barred male over non-barred hens does not work, and a Delaware rooster over red hens gives chicks that all look alike

Drawn by HenClass from the University of Kentucky's sex-linked crosses page and ASC-231, Poultry Extension's sex-linked traits and chick-sexing guides and Mississippi State Extension P3036. Stylized birds; colors approximate. Not to scale.

Why the cross works only one way

Birds reverse the mammal system: males are ZZ and females ZW, so it is the hen, not the rooster, that determines the sex of each chick (University of Kentucky; Wikipedia). Poultry Extension lists the sex-linked plumage traits: color and pattern such as barred versus non-barred, the silver factor, which inhibits red pigment in feathers, and the speed of feather growth. A sex-link uses one of these on a specific pairing of breeds:

Gold rooster × silver hen. Sons come out silver and daughters gold (Poultry Extension's guide to sexing day-old chicks). The Delaware shows what happens the other way round: a Delaware hen over a Rhode Island Red or New Hampshire rooster gives sons with the Delaware pattern and solid red daughters, while a Delaware rooster over red hens gives chicks that all share the Delaware pattern and cannot be sorted by color.
Non-barred rooster × barred hen. Daughters feather out non-barred like their father and sons barred like their mother. Kentucky Extension states plainly that the reverse cross does not work; Poultry Extension adds that a barred male over non-barred females fails.
Barring is dominant. The Livestock Conservancy describes the barred pattern as a dominant sex-linked gene, with two copies in males and one in females, which is why purebred Barred Rock cocks usually look lighter than hens.
Both at once. A gold, non-barred Rhode Island Red male over a silver Barred Plymouth Rock female gives black-and-red, non-barred daughters and black-and-white, barred sons (Poultry Extension).
Avoid white roosters. Kentucky's ASC-231 says the male must lack the dominant white gene, and Wikipedia warns that white birds should not be used because the white allele is sometimes dominant and sometimes recessive.

How sex-link chicks are sexed, compared with other methods

Method	What you look at	Accuracy reported
Down color, red sex-links	Males hatch white; females hatch buff or red (Kentucky)	No figure in the extension sources
Down color, black sex-links	All chicks black; males have a white dot on the head. University of Maine describes the male's spot as irregular and the female as fully black	Cackle Hatchery lists 95–100% for its own birds
Head spot, purebred Barred Rocks	Males have a large white spot on top of the head, females a smaller, narrower one	About 80% (Poultry Extension)
Wing spot, Rhode Island Reds and New Hampshires	A white spot on the down over the wing web in males	Not always accurate: spot size varies (Poultry Extension)
Feather sexing	Fast-feathering male × slow-feathering female: sons slow-feathering, daughters fast-feathering. The slow-feathering gene K sits on the Z chromosome. Readable only about one to three days after hatch	No figure given; Poultry Extension notes commercial white-egg strains are sorted this way
Vent sexing	The hatchery method, brought to North America from Japan in the 1930s; needs extensive training	No figure given
Egg shape, string-and-needle tests	Folk methods	No better than about 50-50 (Poultry Extension)

Two fluffy buff-orange chicks with darker reddish-brown stripes down their backs, eating from a metal feeder tray on a paper towel under pinkish light — Two 3-day-old female red sex-link chicks, described on the Commons file page as Golden Sex-Link, also known as Cinnamon Queen, feeding in a brooder under a heat lamp. Female red sex-links hatch buff or red; their brothers hatch white (University of Kentucky).
Photo: lwmhuber / CC BY-SA 3.0, via Wikimedia Commons

Laying: what each source reports

Source	Bird	What it says
Mississippi State Extension (2026)	Sex-links in general	"Extremely good egg layers," "300 eggs per year or more"
Wikipedia	Sex-links in general	Often 300 or more a year, depending on care and feed
Myers Poultry (its own birds)	Red Sex Link	285–300 a year under optimal care; start laying at 16–20 weeks
Cackle Hatchery (its own birds)	Black Sex Link	200–280 a year, labeled estimates; large eggs; hens 6–7 lb
McMurray Hatchery (its own birds)	Black Star, Red Star	Black Stars can lay 4 or more eggs a week in good conditions and start at 22–24 weeks; Red Stars start at about 22 weeks
University of Kentucky, ASC-231 (2018)	Sex-linked crosses	No figure; less productive than commercial strains such as Hy-Line, ISA, Shaver or Bovans, but may suit small-scale systems better
Cruz Bermúdez et al. (2021), Costa Rica	Sex Link Black and Rhode Island Red hens with grazing access, 13–80 weeks old	Both lines produced less than the ISA Brown line (abstract)

The sources disagree on where sex-links sit. Mississippi State puts them at 300 or more eggs a year; Kentucky ranks them below commercial layer strains; hatchery figures describe each hatchery's own line. Names blur the picture too: McMurray's page gives ISA Brown as another name for its Red Star, and Wikipedia lists the ISA Brown, a commercial hybrid, among red-linked birds. Laying also falls as hens age; see how long hens keep laying or estimate your flock's output with the egg production calculator.

Breeding your own sex-links

Start from purebred parents. Use the rooster and hen breeds in the table above. Barred Rock hens with a Rhode Island Red rooster are the standard black sex-link pairing (see the Plymouth Rock and Rhode Island Red pages).
A bantam version exists. University of Maine suggests a Rhode Island Red bantam male over Barred Plymouth Rock bantam females for a black bantam sex-link.
The next generation will not sort. Kentucky says the offspring are hybrids that will not breed true, and Poultry Extension says the offspring of a sex-linked cross cannot be used in a second sex-linked cross. McMurray and Myers Poultry also say their sex-link hybrids do not breed true.

Checklist before you order or hatch sex-links

Ask which cross it is. "Red Star" and "Black Star" are catalog names; ask the hatchery for the sire and dam breeds.
Ask about sexing accuracy. Color sexing is not perfect even in a correct cross; Cackle, for example, lists 95–100%.
Check chicks on arrival. In red sex-links the pale chicks are males; in black sex-links a white dot on the head marks a male.
Expect brown eggs and plan feed and nest boxes for laying from around 16 to 24 weeks, the range hatcheries give; see feeding laying hens.
Do not plan a second generation of sex-links from your own sex-link hens.
Set up the brooder first; see chick care for the first 8 weeks. Terms like straight run and sexed chicks are in the glossary, and other breeds in the breed directory.