Northern Pacific Rattlesnake — Fact Sheet

Crotalus oreganus · Northern Pacific Rattlesnake

📋 At a glance

🏠 Enclosure

• Locked indoor primary enclosure inside a secondary escape-proof room.
• Minimum 180 x 90 x 90 cm for one adult; house singly.
• Full-body positively lockable shift, two-step locks and neonate-proof gaps.
• 8-12 cm compactable mineral soil/sand/clay; disposable quarantine substrate.
• Avoid unstable talus, aromatic wood and deep uninspectable clutter.
• Protected contact only; two trained adults with communications at every opening.

🪨 Enclosure furniture

• Snug warm and cool refuges plus one ventilated humid hide.
• Anchored rock-textured shelf/cork and low cover.
• Clear inspection lane, stable water bowl and protected service port.
• Keep lamps, probes and wiring outside containment or behind locked guards.

💡 Lighting

• UVB recommended: measured Ferguson Zone 2 over part of the warm zone.
• Linear UVB plus bright white visible light with full shade.
• Replace lamps by manufacturer guidance and meter output.
• 9-15 hours seasonally, changed gradually; complete darkness at night.

🌡️ Temperature

• Basking spot: 29-32 °C

• Warm zone: 22-27 °C

• Cool zone: 17-21 °C

• Night: 12-18 °C

• Preserve a cool retreat; do not maintain northern stock at desert temperatures.

• Measure air/surface separately; thermostat, guard and alarm heat.

• Never use unguarded heat rocks or heat the entire floor.

💧 Humidity & water

• Ambient 40-60%; 60-75% in one ventilated shed refuge.
• Permanent fresh water through protected access.
• Avoid saturated substrate, condensation and stale air.
• Persistent soaking or poor shed → review heat, hydration, mites and disease.

🐁 Diet

Feed freely:

• Appropriately sized frozen-thawed mice; juveniles every 7-14 days.

In moderation:

• Small rats for large adults every 14-28 days; reduce with season.

Avoid:

• Live prey, oversized meals, winter feeding before cooling and loose feeding tubs.

Supplements:

• None routinely with complete whole vertebrate prey.

💤 Brumation

• For healthy, established, locality-documented adults in managed breeding only.
• After fasting and gut clearance, cool gradually to 5-10 °C with professional review.
• Do not cool juveniles, new arrivals, gravid, thin, dehydrated or ill snakes.
• Monitor temperature, humidity and body mass; do not give California stock a Canadian schedule automatically.

🩺 Health — warning signs

• Constant cool-hide use/restlessness → overheating.
• Thick body → obesity from year-round feeding and warmth.
• Weight loss during brumation → unsafe cycle, dehydration or disease.
• Poor shed/concentrated urates → hydration or temperature problem.
• Bubbles, wheeze, mouth lesions, mites or abnormal faeces → prompt veterinary assessment.
• Burn/crushing injury → unsafe heater or unstable décor.

Secure behind the shift and use an experienced reptile veterinarian; envenomation requires immediate hospital care, never home treatment.