Rabbit Anatomy 101: The Nose

Reviewed by Lucile Moore, PhD.

Growing up, I watched a popular television series called Bewitched. Samantha Stevens, the suburban witch, had a famous nose twitch that always reminded me of a cute little rabbit. While rabbit's noses aren't quite as magical as Samantha's (although I would argue that their adorable nose twitches certainly seem to cast a spell on me), they're still pretty fascinating nonetheless.

Rabbits (along with mice and dogs) are considered macrosmatic species meaning their sense of smell is highly developed, while humans are microsmatic species (meaning, you guessed it, we have a poor sense of smell)². Despite being mediocre with our schnozes compared to other species, humans can still detect up to a trillion different smells¹! It is the current scientific understanding that rabbit's have about 100 million olfactory receptors for smell in their nose compared to humans who have an estimated mere 5-6 million. With 20 times more receptors than us, it's difficult to even imagine the vast array of smells that rabbits can detect!

Olfactory receptors are located in the nasal passageway and bind to odor molecules which then sends that information to the brain. So when you peel a banana, it releases tiny little odor molecules that scurry their way into a rabbit's nasal passage and bind to their olfactory receptors. A message then gets quickly sent to their brain and the brain says "I detect banana! Yes please!"

More than just a cute tool for begging

If you are blessed with having a pet rabbit, you've certainly noticed how fast their noses can twitch/wiggle especially when an enticing treat is near. In just one minute, they can wiggle up to 150 times! Some call this "nose blinking".

By wiggling its nose, the rabbit exposes more of those 100 million receptors to the air and the smells the air contains. The faster it wiggles, the more receptors are exposed³.

Rabbits - both wild and domesticated - communicate in most parts of their life through their noses. Rabbit noses are clearly more than just a cute tool for begging. They are:

✔️ a necessary respiratory function

Rabbits are obligate nasal breathers meaning they must breathe via their nose as opposed to their mouth. Rabbits with respiratory disease (one of the most common diseases in rabbits, especially in dwarf breeds) will attempt to breathe through their mouths, which prevents feeding and drinking and could be fatal⁴. They do not pant like other species but rather as their activity level increases, so do their nose wiggles. It is not vital that rabbits wiggle their noses to breathe (it's similar to when we flare our nostrils to take in a deeper breath or scent) so don't worry if you see their nose virtually unmoving...they are likely just very relaxed or sleeping!

✔️ a cooling mechanism

Rabbits have specific nasal glands that moisten air as it is breathed in, which has a role in thermoregulation⁵ (regulating their body temperature). However, this is not an efficient method of releasing heat. The majority of heat is released through the ears and it's difficult for rabbits to cool themselves down so they are easily susceptible to heat stroke.

✔️ food locator

Anyone who lives with a pet rabbit knows how good they are at finding where you hide their most treasured treats! Food selection and ingestion is based on smell and from tactile information gained from the sensitive whiskers around the nose and lips⁵. Because rabbits don't have great vision really close up, they rely on their sense of smell rather than sight to select their food. However, this won't stop me from plating their greens in a very aesthetically pleasing way while pretending like I'm a 5-star chef!

Herbal forages are a wonderful way to enrich your pet rabbit's life, encouraging them to do what they do best: sniff around and forage! Each herb has a unique smell which can provide stimulating enrichment for your bunny's brain. Just watch as they wiggle their noses in excitement!

✔️ perceiving danger, marking territories, & attracting mates

Although they are not native to every continent, rabbits are now found throughout the world. Their superior survival skills have been attributed to their fine-tuned, highly developed sense of smell². They can perceive predators with their noses even when their eyes and ears have failed to do so.

Along with making sure dangerous predators stay away, wild rabbits also want to ensure that rabbits from other colonies know their territory lines. They will spray urine (and leave fecal droppings) around their territory to say "this is MY house!" to any curious rabbits wandering nearby. This behavior has carried over into our domesticated rabbits; both unaltered males and females will mark their territory in the home by spraying. It's important to have your rabbits spayed and neutered for so many reasons but certainly the stinkiest reason of all is this!

Sometimes males will spray other males who are lower-ranking and females during courtship⁶. "Chinning" is another courtship ritual as well as a way to mark territory. Rabbits have scent glands on the underside of their chins that secrete scent signals which are undetected by humans. You'll oftentimes see them rubbing their chin on items around the house or even you! I can almost hear them as they are doing it saying "mine. mine. mine. yep, mine too".

✔️ a sweet spot

Most pet rabbits tend to really enjoy being gently pet on the bridge of their nose up over their forehead. This is a safer zone for them to be pet versus their backs or bum which are sensitive areas as prey animals.

 

 

Things to Consider Regarding the Bunny Nose

With such sensitive sniffers, we've compiled a list of things specifically regarding scent that you may not have considered before with your pet rabbit. While this powerful skill helps keep them aware of their surroundings and potential predators, it also makes the membranes inside their nostrils incredibly sensitive and easily irritated.

  • The smell of natural predators (dogs, cats) during vet visits can cause intense stress for your bunny. Try asking your vet if you and your bun can wait in your car (with AC on during hot months of course!) until your appointment time.
  • It's important to consider what cleaning products you use in your home. They might be extremely strong for your bunny's nose and potentially toxic to them. What cleaning products do you use? Do they have artificial or strong chemical smells? Consider using non-toxic, pet friendly cleaners like our Pet Friendly All-Purpose Citrus Infused Cleaner.

  • What other scents imbue your home and your rabbit's environment that might be affecting their well-being? Do you have artificial scents like Glade Plug-ins? Do you use room sprays like Febreeze? Considering switching to oil diffusers or natural soy-based candles. Our bunny-loving friends over at Chez Lapin make amazing cruelty-free candles! Note: even natural, organic scents can be overwhelming for bunnies, especially if they are in a closed-off room with minimal air flow.
  • Steer clear of cedar and pine shavings litter for your rabbit's litter box. They contain toxic phenols that can cause respiratory and/or liver issues. Be sure you regularly clean their litter box; rabbit's urine contains ammonia which can build up and have negative affects on the respiratory system.
  • Cooking really potent food or food that produces a lot of smoke can cause distress for your bunny. In the wild, smoke = fire. An instinctual response to smoke is to run away from it. Our rescue rabbit, Symphony, hates cooking smells with a passion. We learned that in his previous home, he was housed in the kitchen and was subjected daily to the powerful smells of cooking. No wonder he still runs away when we start cooking!
  • Perfumes, lotions, laundry detergent and other scents that you put on your body can be extremely deterring to your rabbit. Often times people misunderstand their rabbit's aversion towards them, taking it personally, when it reality they may just really dislike your perfume! Consider washing your hands before interacting with your bunny and using non-toxic, scent-free laundry detergent (especially for items that specifically belong to your rabbit like blankets, pads, or Hop n' Flops®)
  • Some behaviors that might be misunderstood as "aggression" towards humans could be miscommunicated due to scents! Biting may be due to mistaking the smell of food or treats on the fingers. Attacking, boxing, or biting may be a result of territorial behavior due to the smell of other rabbits on you if you've visited with any recently.
  • Rabbits have been subjected to being used as a laboratory animals for inhalation toxicology tests (and many, many other tests). Can you imagine your pet having to go though something so awful? No animal should have to experience lab tests. Consider using only products that are 100% cruelty free. We recommend using Cruelty Free Kitty. They are constantly updating brands that are either newly cruelty free certified or have recently lost their certification.
  • Upper Respiratory Infections are a common, but no less dangerous, occurrence in domestic rabbits. When checking your rabbits' nose during their Monthly Wellness Check, you should ensure that their nose is clean, dry, free from scabs or crusties, and not runny.

What Can Affect the Rabbit's Nose & Sense of Smell?

Overhead feeders increase the likelihood of dust and fragments of hay entering the nose or eyes. Small bits of hay can become lodged in the nose (as well as eye, mouth, larynx) and can cause serious issues.

Certain neurological diseases can affect the sense of smell.

Allergies from environmental pollen, mold, or dust can cause respiratory issues which can affect the sense of smell due to discharge build up. Our Respiratory & Allergy Relief Herbal Forage is a holistic mix of herbs packed with powerful nutrients, vitamins, minerals, and antioxidants to boost the immune system and support the respiratory system. This is an especially useful blend for those with chronic upper respiratory infections, allergies, watery eyes, and other respiratory issues.

Overbreeding: short compacted faces in dwarf rabbits as well as lop rabbits of all sizes (because of the facial characteristics bred into lops) can lead to many health issues including respiratory disease and malocclusion (teeth issues). That cute lop face unfortunately comes at a price for the rabbits. Check out this article in The Washington Post about rabbit's being overbred and the negative impact on their health.

TL;DR

Rabbits' sense of smell is 20x more powerful than ours! While this special gift helps them navigate through life and protects them from danger, it also means that their noses are extremely sensitive and easily irritated. There are many factors to consider like what cleaners, perfumes, lotions, detergent, etc. you use which can help ensure your rabbit's nose is happy and healthy! Certain "negative" behaviors like could be due to scents (i.e. the smell of food on fingers, causing accidental nipping or the smell of other rabbits causing territorial/aggressive behavior).

SOURCES:

1. https://www.science.org/content/article/human-nose-can-detect-trillion-smells-rev2
2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4907833/
3. https://www.sfgate.com/homeandgarden/article/Bunnies-twitch-their-noses-for-information-3215094.php
4. https://www.vin.com/apputil/content/defaultadv1.aspx?id=5328323&pid=11349&print=1
5. https://www.sciencedirect.com/book/9780702049798/textbook-of-rabbit-medicine
6. https://www.avianexoticvetcare.com/handouts/small-mammals/rabbits-behavior.pdf
7. https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/scent-glands