Gyrfalcon: incubation period, weaning age and breeding
Gyrfalcon eggs hatch after 34–36 days of incubation. Chicks fledge at 46–56 days and are weaned and independent at about 90–120 days. A typical clutch is 2–5 eggs.
Breeding numbers
| Item | Value |
|---|---|
| Adult weight (g) | 805-2100 |
| Male weight (g) | 805-1350 |
| Female weight (g) | 1180-2100 |
| Length (cm) | 48-65 |
| Wing chord (mm) | m 345-380, f 375-410 (wild range 345-410) |
| Clutch size | 2-5 (usually 3-4) |
| Incubation (days) | 34-36 |
| Fledging (days) | 46-56 |
| Weaning / independence (days) | 90-120 |
| Lifespan (years) | 15-20 (captive 20+) |
| Breeding season | Wild Arctic: lays late April-May. Captive (Europe/N. America breeding farms, most AI): pairing Feb, eggs mid-March-April; Gulf climate-controlled units similar. |
| Sexing | Reverse size dimorphism: female ~1/3 heavier (falconers: falcon vs tiercel; Gulf: "tabaa" for the male peregrine, "qarmousha" or "wakri" for the male saker). Chicks and hybrids: DNA (feather/blood) is reliable; size alone overlaps between species and hybrids. |
| Moult | Gulf practice: moulting room ("mqeez") mid-April/May to Sept/Oct after the season; one complete moult per year, natural moult starts in the breeding season (females during incubation). |
| Quarry | Houbara, stone curlew, herons, hare; in the north grouse, ducks, geese. |
| Gulf heat tolerance | 1/5 - very poor; needs air-conditioned mews/moulting room (≈20-24 °C), low humidity, never fly in midday heat. |
| Temperament | Bold, intelligent, powerful; slower to make than a peregrine, can be stubborn; imprints become strong hunters. |
| Disease prevention | Prevention: aspergillosis (heat stress, dust, poor ventilation, transport/stress - Gulf summer & start of season); bumblefoot (overweight, inactivity, hard/smooth perches - use padded/astroturf perches, keep talons trimmed); frounce/trichomoniasis and falcon herpesvirus (both from feeding pigeons/doves - avoid wild or unknown pigeons, freeze food); sour crop/ingluvitis (feeding before the crop empties, spoiled or warm meat); coccidiosis (young birds, damp mews); avian pox (mosquitoes - vaccine available); lead (shot quarry/pigeons). Vet for diagnosis & treatment. Gyrs and high-gyr hybrids are the most aspergillosis-prone. |
| Identification features | Largest falcon; broad wings, long broad tail - at rest wingtips reach only ~2/3-3/4 of tail; weak or no moustache; short toes vs peregrine; adult cere/feet yellow, juvenile blue-grey; juvenile brown-streaked below, adult barred/spotted. |
Origin: The Arctic: Iceland, Greenland, Canada and Siberia — Scientific name: Falco rusticolus
Size: Male 800-1300 g, female 1130-2100 g
Breeding and care tips
The largest, strongest and most expensive falcon in the Gulf, especially the white. Very heat-intolerant: an air-conditioned, well-ventilated moulting room is essential and it is the species most prone to aspergillosis. Most farm production is by artificial insemination from imprinted males.
Description
The largest falcon: broad wings and a long broad tail, wingtips reach only about two-thirds of the tail, weak or no moustache.
Need the exact date? Use the egg hatch calculator and the weaning age chart.
Related species
- Saker falcon
- Peregrine falcon
- Barbary falcon
- Lanner falcon
- Laggar lugger falcon
- Prairie falcon
- Aplomado falcon
- Merlin
Frequently asked questions
How long do Gyrfalcon eggs take to hatch?
Gyrfalcon eggs hatch after 34-36 days of incubation.
How many eggs does a Gyrfalcon lay?
Usually 2-5 (usually 3-4) eggs per clutch.
When do Gyrfalcon chicks leave the nest?
Chicks fledge at about 46-56 days old.
When are Gyrfalcon chicks weaned?
They are weaned and independent at about 90-120 days.
What is the Gyrfalcon breeding season?
Wild Arctic: lays late April-May. Captive (Europe/N. America breeding farms, most AI): pairing Feb, eggs mid-March-April; Gulf climate-controlled units similar.
How do you tell a male Gyrfalcon from a female?
Reverse size dimorphism: female ~1/3 heavier (falconers: falcon vs tiercel; Gulf: "tabaa" for the male peregrine, "qarmousha" or "wakri" for the male saker). Chicks and hybrids: DNA (feather/blood) is reliable; size alone overlaps between species and hybrids.
How long does a Gyrfalcon live?
About 15-20 (captive 20+) years with good care.