Small Pets · Gerbils
Mongolian Gerbil
Meriones unguiculatus
A desert rodent driven to dig and burrowBeginner
- Lifespan
- 3-4 years
- Size
- 10-15 cm body, plus tail
- Social needs
- Social; keep same-sex pairs or small groups
- Time
- Daily feeding and checks; weekly spot-cleaning
- Cost
- Low
- Diet
- Quality gerbil seed/grain mix plus occasional protein
Overview
What is this animal?
- The Mongolian gerbil is a small desert rodent that is active in short bursts through the day and night.
- Hardy, clean and fairly low-odour, it is a good beginner pet for those who enjoy watching natural behaviour.
- Gerbils are strongly driven to dig and tunnel, so their care centres on deep substrate for burrowing.
- They are social and should not be kept entirely alone.
Temperament
- Gerbils are curious and busy and rarely aggressive toward people.
- They tame readily, often coming to the hand to investigate, and are engaging to watch as they dig, store food and groom each other.
- They are social and should live in compatible same-sex pairs or small groups, ideally littermates introduced young.
- Falling out (declanning) can occur, so monitor group harmony and do not house unfamiliar adults together carelessly.
A good fit for
- Beginners wanting an active rodent
- Keepers interested in digging behaviour
- Those wanting a low-odour pet
- Owners able to house a pair
Common mistakes to avoid
- Shallow substrate preventing natural burrowing
- Plastic cages they chew through
- Handling by the tail, causing injury
- Keeping a single, lonely gerbil
Enclosure
Minimum 75 litres (20 US gallons) — for the pair
Cannot be kept alone. The minimum is 2, and the space above is for that group.
- A gnaw-proof tank or convertible enclosure of at least 75 litres suits a pair, with a deep layer of substrate (20cm or more) so they can build real burrow systems.
- Avoid plastic-only cages, which they quickly chew through.
- Mix paper-based bedding with hay for stable tunnels, and add a sand bath, wooden chews and a solid-surface wheel of 20cm or more in diameter.
- Keep them at room temperature, out of direct sun and away from damp.
Supplies
Setup
- Enclosure of an adequate size
- Water bottles, bowls, hides and enrichment
- Carrier and travel box
- Digital kitchen scale
Ongoing
- Quality gerbil seed-and-grain mix
- Dried or live mealworms and small roaches
- Loose meadow hay for burrowing and fibre
- Water bottle with a bottle brush
- Small ceramic dish for fresh food
- Untreated wooden chews
- Kitchen scale for weekly weigh-ins
Safe substrate: Deep paper and aspen mix, 20 cm or more · Plain chinchilla bathing sand · Hay woven through the substrate
Care routine
Daily
- Company and time out
- Feed and clear yesterday's leftovers
- Fresh water
- Spot-clean the enclosure
- Watch them while they are awake
Weekly
- Change the sand bath
- Fresh cardboard and wood
- Hands-on health check
- Rotate enrichment
- Weigh-in
Monthly
- Top up deep substrateevery 2 weeks
- Full cleanevery 3 weeks
- Check nails and teeth
- Check supplies and dates
Vet: Annual exam — every 12 months (every 6 months from 2 years old)
Top resources for more info
Independent creators and organisations we would send a friend to. We have no affiliation with any of them, and nothing here is sponsored. Links checked 2026-09-19.
YouTubers
Victoria RaechelHamster and rabbit care, cage setups and honest myth-bustingEmiologyRat and mouse care from a zoology graduate; housing, diet, enrichmentScotty's AnimalsGuinea pig and small-animal care from a rescue volunteer
Sites
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Diet
- Feed a quality gerbil mix of seeds and grains, scattered to encourage natural foraging.
- Supplement occasionally with a little fresh vegetable, a mealworm or other small protein source, and offer hay for fibre and enrichment.
- Fresh water must always be available from a bottle.
- Limit fatty sunflower seeds and avoid sugary or citrus foods.
- As desert animals gerbils drink little, but they still need constant access to clean water.
Health
- Gerbils are generally robust but can suffer tail-skin injuries if handled by the tail tip, so always scoop them from the body.
- Overgrown teeth, scent-gland tumours and stress-related seizures can occur.
- Watch for sore noses caused by digging in dusty or dirty bedding.
- Monitor weight and activity, and seek an exotics vet promptly for lethargy, lumps or breathing changes.
Is your enclosure big enough?
Minimum volume75 litres (20 US gallons)
CompanyCannot be kept alone. The minimum is 2, and the space above is for that group.
Is this urgent?
Small mammals are prey animals. They mask pain and illness by instinct, so by the time something is obvious it is usually already advanced.
Go now
Not eating, or eating far less than normalCall an exotics vet. Bring a recent weight if you have one. In a hindgut fermenter the gut slows and then stops when food stops moving through it. This is the single most common emergency in small mammals.
8 hoursNo droppings, or droppings suddenly tiny, misshapen or scarceCall an exotics vet now. Take a photo of the litter tray. Output is the most reliable read on gut movement there is, and it fails before the animal looks unwell.
8-12 hoursSitting hunched, pressed to the floor, unwilling to moveGo now. A hunched, still posture in a prey animal is a pain posture.
NowAudible teeth grinding or crunchingGo now. Soft tooth purring is contentment. Loud, slow grinding is pain.
NowHard, bloated or drum-tight abdomenGo now. Do not offer food or attempt to massage the abdomen. Gas or an obstruction can become fatal within hours and needs imaging, not home care.
NowLaboured breathing, open-mouth breathing, or clickingGo now. Keep the animal cool and undisturbed in transit. Most small mammals are obligate nose breathers; open-mouth breathing means they are already struggling.
NowMaggots or fly eggs anywhere on the animal, especially the rearGo now. Do not attempt to wash them off first. Flystrike can kill within a day. Risk rises sharply in warm weather and in any animal with a dirty or damp rear.
NowToday
Head tilted persistently to one side, or circlingBook today. Several causes, most of which respond far better to early treatment.
TodayWeight down 5 percent or more since the last weighingCall today, and bring the weight history. Weight falls before appetite visibly changes. This is why weekly weighing is worth the two minutes.
TodaySoon
Drooling, wet chin, or dropping food while trying to eatBook a dental check. Continuously-growing teeth can overgrow into the tongue or cheek long before the animal stops trying to eat.
A few daysScratching hard enough to break skin, or bald patches spreadingBook an appointment. Mites and fungal infections spread, and some transfer to other animals in the household.
A few daysHave the number of an exotics-competent practice saved before you need it. Most general small-animal clinics do not treat rabbits or rodents out of hours, and finding one at 11pm is not realistic.
This is general guidance for a healthy adult, not a diagnosis. An exotics vet who knows your animal always overrides it — and the time to find one is before you need one.
Can a mongolian gerbil eat that?
Most small companion mammals are hindgut fermenters: the gut is a fermentation vessel that has to keep moving, and sudden rich food stops it.
The full list
Never (19)
AlcoholNo safe amount at any body weight on this site.
neverAvocadoPersin, concentrated in the skin, stone and leaves. Implicated in cardiac damage across birds, rodents and reptiles.
neverBread and baked goodsRefined starch ferments in the hindgut and causes gas and stasis. No nutritional case for it either.
neverCaffeineCoffee, tea and energy drinks. Cardiac and neurological toxicity at tiny doses for an animal this size.
neverChocolateTheobromine and caffeine. Small mammals and reptiles cannot clear either.
neverDairyAdults are lactose intolerant and the gut flora cannot handle it.
neverDried fruitSugar concentrated several times over, and it sticks to the teeth. Most commercial small-pet treats are exactly this.
neverGarlicSame allium toxicity as onion, and more concentrated by weight.
neverIceberg lettuceAlmost entirely water with negligible nutrition, and it contains lactucarium, which causes diarrhoea in quantity. It displaces food that would have been useful.
neverLeekAllium family. Same mechanism as onion and garlic.
neverMeatA hindgut fermenter has no way to process animal protein. It disrupts the gut flora the animal depends on.
neverMushroomsNot part of any of these animals' natural diet, and the risk from misidentified varieties is not worth the zero upside.
neverNutsFat and phosphorus loads a herbivore is not built for, and a choking risk.
neverOnionOrganosulphur compounds damage red blood cells. The whole allium family is out.
neverPotatoSolanine in the skin and any green part, plus a starch load the hindgut cannot handle.
neverRaw beansLectins. Also a gas producer in a species that cannot vomit or belch.
neverRhubarbVery high in soluble oxalate, high enough to cause acute kidney injury. The leaves are worse than the stalks.
neverSalty or seasoned human foodSalt, oil and seasoning. Crisps, chips, seasoned leftovers and processed meat are all out.
neverSweetcornThe hulls are indigestible and are a recognised blockage risk in small herbivores.
neverRare treats (13)
AppleSugar. The seeds contain a cyanogenic compound and must be removed. A thin slice, once or twice a week. Never the seeds or core.
rare treatBananaVery high in sugar and starch, and most animals will overeat it given the chance. A slice the width of a fingernail, rarely.
rare treatBlueberrySugar, but a small portion size makes it easy to control. One or two berries, twice a week.
rare treatBrussels sproutsHighly gas-forming. Half a sprout, rarely.
rare treatCarrotSold as the archetypal rabbit food and it is nothing of the kind: carrot is a root vegetable with a high sugar content. The leafy tops, by contrast, are an excellent green. A thin slice as a treat. The tops can be fed freely.
rare treatCauliflowerOne of the most gas-forming brassicas. A very small piece, occasionally.
rare treatGrapesVery high in sugar. Halve them, because a whole grape is a choking hazard. One halved grape, rarely.
rare treatOrangeAcidic and sugary; can irritate the mouth and gut. A tiny segment, rarely if at all.
rare treatPearSugar. Remove the seeds. A thin slice occasionally.
rare treatPeasHigh in starch and sugar. The pods and leaves are better than the peas. A few pods occasionally.
rare treatStrawberrySugar, though lower than most fruit. The leaves are actually the better part. Half a small berry, once or twice a week.
rare treatTomatoThe ripe flesh is safe in small amounts. The leaves, stems and any green fruit contain solanine and must never be offered. A small piece of ripe flesh, occasionally. Never the plant.
rare treatWatermelonSugar and a very high water content, which together can loosen the gut. Remove the seeds. A small cube in hot weather, rarely.
rare treatOccasional (17)
BasilSafe and well liked. Rotate rather than relying on it. A few leaves.
occasionalBok choyGood green, mildly goitrogenic like other brassicas. A leaf or two a few times a week.
occasionalBroccoliNutritious but a notable gas producer. Leaves and stalk are better tolerated than the florets. A small floret or a piece of stalk, twice a week.
occasionalCabbageA brassica. Gas-forming in quantity, and goitrogenic with heavy long-term feeding. A small piece, once or twice a week.
occasionalCelerySafe and well liked. Cut across the stalk so the long fibres cannot catch. A short piece, cut into segments.
occasionalChardSame oxalate issue as spinach. A small leaf, occasionally.
occasionalCourgetteSafe and mild. Serve raw. A few slices a few times a week.
occasionalCucumberSafe, but it is mostly water with very little in it. Useful for hydration in warm weather, poor as a staple. A few slices.
occasionalDillSafe in rotation. A few fronds.
occasionalGreen beansSafe cooked or raw in small amounts. Gas-forming in quantity. One or two, occasionally.
occasionalKaleHigh in calcium and a mild goitrogen. Genuinely nutritious, but not the everyday green it is often sold as. A leaf or two, two or three times a week.
occasionalMintSafe in small amounts; strongly flavoured and not every animal wants it. A leaf or two.
occasionalParsleyNutritious but relatively high in calcium. Fine in rotation, not as the whole green portion. A few sprigs, a few times a week.
occasionalPumpkinSafe and well tolerated in small amounts. A small cube occasionally.
occasionalRocketPeppery and well tolerated in rotation. A small handful, a few times a week.
occasionalSpinachHigh in oxalates, which bind calcium and contribute to bladder sludge and stones in animals prone to them. A single small leaf, no more than once or twice a week.
occasionalWatercressNutritious, strongly flavoured, high in calcium. A small handful occasionally.
occasionalEveryday foods (6)
Bell pepperOne of the best everyday vegetables here: high in vitamin C, low in sugar, no oxalate problem. Remove the seeds and stalk. A few strips daily.
everyday foodCarrot topsThe leaves are a proper green and much better food than the root. A handful as part of the daily greens.
everyday foodCorianderWell tolerated, aromatic, and most animals take it readily. Part of a daily mixed handful.
everyday foodDandelion leavesOne of the best greens available, and free. Pick well away from roadsides and anywhere that may have been sprayed. A generous handful daily.
everyday foodGrass hayShould be about 80 percent of what this animal eats, available at all times. It is what wears the teeth down and what keeps the gut moving. Unlimited, always.
everyday foodRomaine lettuceDark leafy lettuce with real nutritional content and a good water balance. A generous handful daily as part of a mixed selection.
everyday foodThat food is not on our list. Do not offer it on a guess — check with an exotics vet, or leave it out. Nothing in a small mammal's diet is urgent enough to risk it.
Introduce any new food one at a time, in a small amount, and wait two days before adding another. A change in droppings is the earliest signal that something did not suit.
What it really costs
Setup, monthly, first year and across a whole life, itemised and with the electricity worked out from the actual wattage. Published figures for the same animal disagree by a factor of four, so the calculator shows ranges rather than picking one.
Bedding and substrate
Gerbils tunnel. Substrate depth is not enrichment for them, it is the enclosure.
Safe
Deep paper and aspen mix, 20 cm or moreA gerbil needs a tunnel that holds its shape. Mixing paper with aspen and a little hay gives it structure.
safePlain chinchilla bathing sandEssential for coat condition.
safeHay woven through the substrateBinds the burrow walls.
safeWith a caveat
Coco fibreHolds a burrow well, but keep it dry — gerbils are desert animals.
with a caveatNever
Pine and cedarAromatic phenols.
neverShallow bedding in a tall cageA gerbil that cannot dig will bar-chew instead, and that is the standard sign of an inadequate setup.
neverCotton-wool nesting materialEntanglement and ingestion risk.
neverCompare with other animals
The same axes for every animal, side by side — the way the guides are written makes that a fair comparison rather than two articles.
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Gerbils, side by side
Same axes, same care guides — the honest way to choose between types.
See all Gerbils side by side →
