Why is my bearded dragon not eating in winter?

What brumation is

Brumation is the reptile equivalent of hibernation — a state of reduced metabolic activity triggered by shortening day length and cooler temperatures in autumn and winter. In bearded dragons (Pogona vitticeps) it presents as:

• Sleeping for longer stretches, often in dark corners or burrowed under substrate.
• Refusing food, sometimes for weeks or months.
• Reduced basking — the dragon ignores the basking lamp even when it's on.
• Reduced defecation (less food in = less out).
• Slight muting of color in some individuals.

Per ReptiFiles' brumation explainer and consistent guidance from BeardedDragon.org's brumation guide, captive brumation varies enormously between individuals: some dragons brumate deeply every winter, some skip years, some never brumate at all. All three patterns are normal.

When brumation is normal — and when it isn't

The normal pattern:

• Age 12+ months (preferably 18 months when growth has plateaued).
• Autumn or winter onset triggered by shortening photoperiod and ambient temperature drops.
• Otherwise healthy dragon — clear eyes, normal urate color (white tip), no mucus, no dark sustained beard, stable weight.
• Gradual onset and resolution over days to weeks at each end.

The not-normal pattern (audit husbandry, see a vet):

• Hatchling or juvenile under 12 months — see next section.
• Sudden onset rather than gradual decline.
• Sunken eyes — dehydration, not brumation.
• Sustained dark beard through the day — stress or illness.
• Significant weight loss (>10 % of body weight).
• Mucus, open-mouth breathing, swelling — respiratory infection or other illness. See "is my reptile sick?".
• Year-round refusal — not seasonal, not brumation.

Hatchlings should not brumate

A hatchling or juvenile bearded dragon (under 12 months, sometimes under 18 months for slow growers) should not brumate. They're still in their primary growth phase and need consistent food and calcium intake to develop bone density and reach healthy adult size.

If a young dragon shows brumation-like behaviour:

1. Audit husbandry first. Verify basking surface 40–43 °C (104–110 °F) with an IR temperature gun (see temperature guide), UVB at UVI 4–6 at basking with a Solarmeter (see UVB guide), correct calcium-with-D3 dusting on insects most feedings.
2. Track weight weekly. A young dragon losing weight or failing to gain is a same-week reptile vet appointment.
3. Watch for illness signs. Sunken eyes, mucus, sustained lethargy at basking temperature — all warrant a vet visit.

What to do during brumation

For a healthy adult that's brumating:

• Keep heat and UVB on during the day. Either at normal 12-hour photoperiod or slightly reduced (10 hours) to mirror seasonal light. Do NOT turn everything off — that's chronic under- husbandry, not brumation support.
• Continue to offer food every 7–14 days even if refused. Some brumating dragons take occasional small meals. Remove uneaten food after a few hours.
• Weigh weekly. A simple digital kitchen scale catches weight trends early. Log the numbers — see the husbandry log guide.
• Offer a shallow bath in lukewarm water once every 1–2 weeks for 10–15 minutes. Many brumating dragons drink during the bath even though they ignore the water dish.
• Don't force-feed. A healthy brumating dragon doesn't need feeding; force-feeding can cause regurgitation and stress.
• Minimal handling. Brumating dragons want to sleep. Don't wake them for cuddles. Daily 30-second visual check is enough.

Coming out of brumation

In late winter or early spring, the dragon emerges gradually as photoperiod naturally increases. Signs of waking:

• Resumed basking under the lamp.
• Active during light hours instead of asleep.
• Occasional defecation as gut activity resumes.
• Eventually accepting offered food.

Resume normal feeding:

• First week: offer greens daily, insects every 2–3 days as appetite returns.
• Week 2–4: normal adult schedule — greens daily, insects 3–5 times per week (see the diet guide).
• Weigh weekly for the first month post-brumation to confirm normal weight trajectory.

Some dragons take 2–4 weeks to fully resume normal eating. If your dragon hasn't resumed any feeding 3–4 weeks after photoperiod normalises and basking activity resumes, that's a vet visit — what looked like brumation may have been the start of an illness.

When to involve a vet

Brumation does NOT need a vet visit for a healthy adult. These signs DO:

• Hatchling or juvenile (under 12 months) showing brumation-like behaviour.
• Weight loss exceeding 10 % of body weight.
• Sunken eyes, sustained dark beard, mucus, open-mouth breathing.
• Refusing food past 4 weeks after expected emergence.
• Any sign that combined with refused food doesn't fit a normal pattern.

The broader husbandry context is in the pillar care guide; the temperature setup is in the temperature guide; the not-eating diagnostic walkthrough is in the not-eating guide.