Flying Squirrel Feeding: Diet, Schedule, and the Calcium Ratio That Prevents Paralysis

A flying squirrel's wild diet of acorns, seeds, fungi, insects, and the occasional bird egg is easy to approximate badly in captivity, and getting the calcium-to-phosphorus balance wrong is the leading cause of serious illness in this species.

The Wild Diet, and What It Means for a Captive One

Wild Southern flying squirrels are omnivores with a genuinely varied diet: acorns and other nuts, seeds, berries and fruit, fungi, tree bark and buds, insects, bird eggs, and occasional carrion, and Animal Diversity Web specifically notes hickory nuts and acorns as their main winter food cache. A 2014 dietary preference study in The American Midland Naturalist tested wild squirrels against several natural food sources and confirmed a real preference among the different acorn types offered rather than random foraging. That's a heavily nut-and-seed diet in the wild, but it's also an animal that's foraging constantly, burning far more energy than a caged pet ever will.

The Captive Framework: Rodent Block, Produce, Protein

Feeding Frequency and Portions

Offer fresh food in the evening. Flying squirrels are strictly nocturnal, most active from dusk through the night, so a morning feeding routine misses their actual appetite window. Keep the rodent-block staple available, add produce daily, and rotate in a protein source several times a week. Fresh water stays available at all times from a bottle mounted to the cage, with the sipper tube checked daily. Keep nuts and seeds to a genuinely small portion, they're calorie-dense and phosphorus-heavy, and a captive squirrel eating them at anything close to wild-forager frequency will run into weight and calcium problems fast.

Foods to Avoid

The core mistake is a diet that's effectively all nuts and seeds, whether that happens by accident or because it's what people assume a squirrel wants. That combination is both too high in fat for a caged animal's activity level and too phosphorus-heavy relative to calcium. Skip chocolate, dairy, candy, and anything processed or heavily salted entirely, none of it appears anywhere in a wild diet, and none of it does a captive squirrel any favors either.

Supplementation: The Part That Matters Most

There's a real difference from sugar gliders here, though. Because flying squirrels can synthesize some vitamin D through skin exposure to light, not just get it from food, keepers are generally advised to provide at least 20 minutes a day of natural or full-spectrum light alongside dietary supplementation, rather than relying on diet alone the way a glider's care sheet might suggest. A calcium and vitamin D3 multivitamin, the same kind of powder sold for sugar gliders, covers the same calcium-and-D3 correction a flying squirrel's diet needs, since the underlying deficiency risk is functionally identical between the two species.

The Mistake That Matters

Left uncorrected, a phosphorus-heavy, calcium-poor diet causes metabolic bone disease: the body leaches calcium out of the bones to keep blood calcium levels stable, and the bones weaken until they fracture. Early signs include lethargy, reduced appetite, and reluctance to climb or move normally, progressing toward hind-limb weakness, tremors, and in advanced cases, paralysis and seizures. That progression can be gradual or, in some cases, alarmingly sudden. Any of those early signs need an exotic vet promptly, not a wait-and-see approach.

The Flying Squirrel encyclopedia profile has the natural history behind the wild diet above.

Sources & Further Reading