Tortoise Runny Nose: RNS Signs and What to Do

If you've noticed moisture, bubbles, or a wet crust around your tortoise's nostrils, take it seriously. A runny nose in a tortoise is not the reptile version of a passing head cold. It's the classic sign of what keepers call Runny Nose Syndrome, or RNS, and vets call upper respiratory tract disease. The reason it deserves attention is simple: left alone, it can become chronic and, in some cases, fatal. That's not meant to scare you at 2am. It's meant to explain why the right move is to act early rather than wait to see if it clears on its own.

The encouraging part is that the earliest and mildest cases are often driven by husbandry, especially temperature, and can start improving once you correct the setup. The important part is knowing which signs mean you're past the point where a warmer basking spot alone will fix it.

Most likely causes

RNS usually has more than one contributor at once. Ranked roughly by how often they're the trigger:

1. Temperatures too low. This is the most common driver. A tortoise kept too cool has a weakened immune system and is far more prone to respiratory infection. For a sulcata, aim for a basking spot around 95 to 100F, ambient daytime temperatures of about 80 to 90F, and nights that don't fall below roughly 65 to 70F. Chronic cold, even overnight, sets the stage.

2. Wrong humidity for the species. Both extremes cause problems, and the right target depends on the species. Sulcatas come from dry regions but still need a humid hide to keep their airways and shell healthy, so the ambient enclosure can be dry while the hide stays humid. A setup that's bone-dry everywhere, or wet and cold, both irritate the respiratory tract.

3. Infection. RNS can be caused by infectious agents, most notably Mycoplasma bacteria and herpesvirus. These are contagious between tortoises and are a major reason to quarantine any new or sick tortoise. Infectious cases often need veterinary diagnosis to identify and treat properly.

4. A foreign body in the nostril. Substrate, a piece of food, or bedding lodged in a nostril can cause one-sided discharge and irritation. This is worth ruling out, but don't go digging in the nose yourself.

5. Stress and weakened immunity. A recent move, overcrowding, poor diet, or any ongoing stressor lowers immune defenses and lets a mild problem take hold. Stress rarely acts alone but often tips a borderline tortoise into full RNS.

Here's the practical read on discharge: thin, clear, watery discharge in a tortoise that's eating well and active is often the husbandry end of the spectrum and may improve with better heat and humidity. Bubbly, thick, or mucus discharge, wheezing, or open-mouth breathing points toward infection and means a vet, fast.

What to do tonight

First, get the temperatures right, since cold is the most common trigger and something you can fix immediately. Check the basking spot with a probe or infrared thermometer and bring it into the 95 to 100F range for a sulcata. Make sure the enclosure isn't dropping too cold overnight, and add a humid hide if there isn't one.

If you keep more than one tortoise, separate the affected animal now. Because Mycoplasma and herpesvirus spread between tortoises, quarantine protects the rest of your collection while you sort out the cause. Wash your hands and, ideally, use separate equipment between animals.

Don't try to treat this at home with over-the-counter remedies or by poking around the nostrils. RNS is frequently chronic, and a vet may need to run cultures or other tests to find out whether it's bacterial, viral, or husbandry-driven before choosing a treatment. Guessing wrong wastes time this condition doesn't give you.

Write down what you're seeing so you can show a clear timeline. Note the date the discharge started, whether it's one nostril or both, the discharge type, appetite, activity, and any sounds when your tortoise breathes. VetGPT lets you log photos, temperatures, and symptoms, get an AI read on how urgent the signs look, and track whether things are improving or getting worse day to day. It organizes what's happening and gives you clean records to hand a vet. It does not diagnose or replace one. For the full care picture on diet, housing, and warmth, see our sulcata tortoise care guide and the broader reptile health tracker.

Above all, find an exotic or reptile vet, not a general small-animal clinic, and do it now rather than waiting for the discharge to thicken. Respiratory disease in tortoises rewards early treatment and punishes delay.

Common Questions

Is a runny nose in a tortoise an emergency?

It depends on the discharge and the rest of the picture. Thin, clear, watery discharge in a tortoise that's eating well and active is often husbandry-related, usually low temperatures, and may improve once you fix heat and humidity. Thick, bubbly, or mucus discharge, wheezing or clicking, open-mouth breathing, puffy eyes, or a tortoise that's stopped eating all point to a respiratory infection and need an exotic vet quickly. When in doubt, get it seen, because respiratory disease in tortoises can turn chronic or fatal.

What is Runny Nose Syndrome in tortoises?

Runny Nose Syndrome, or RNS, is a common name for upper respiratory tract disease in tortoises. It can be triggered by infectious agents like Mycoplasma bacteria or herpesvirus, or by poor husbandry such as being kept too cold or too dry, often a combination. It frequently becomes chronic, which is why a vet may need to run cultures or other tests to find the cause rather than just treating the symptom.

What temperature and humidity does a sulcata tortoise need to avoid a runny nose?

Sulcatas need a warm setup. Aim for a basking spot around 95 to 100F, ambient daytime temperatures of about 80 to 90F, and nights that don't drop below roughly 65 to 70F. Even though sulcatas come from dry regions, they still need a humid hide to keep their airways and shell healthy, so the ambient can be dry while the hide stays humid. Chronic cold or the wrong humidity for the species weakens the immune system and is a frequent trigger.

Is a tortoise runny nose contagious to my other tortoises?

It can be. Infectious causes like Mycoplasma and herpesvirus spread between tortoises, which is why any new or sick tortoise should be quarantined away from the rest, ideally with separate equipment and hand-washing in between. A tortoise can also carry and spread these agents without obvious symptoms, so quarantine new arrivals for an extended period and have a vet screen before mixing.