Best Diet for Jumping Spiders: What to Feed for Health, Growth, and Longevity

Jumping spiders are active visual hunters, so the best diet is usually live prey that moves naturally and matches the spider’s size. In captivity, many pet parents use fruit flies for spiderlings and smaller species, then graduate to house flies, bottle flies, bean beetles, roach nymphs, or very small crickets for larger juveniles and adults. A practical rule is to choose prey that is about the same size as the spider’s body or a bit smaller. Oversized prey can stress the spider, cause injury, or be ignored.

Variety is helpful. Feeding the same insect every time may be convenient, but rotating prey can improve enrichment and may support more balanced nutrition. Captive-raised feeder insects are safer than wild-caught bugs because wild insects may be exposed to pesticides or carry parasites. This matters for small arthropods, where even low toxin exposure can be a big problem.

Hydration is part of diet, too. Many jumping spiders do not drink from bowls and instead take water from fine droplets on enclosure surfaces or decor. Light misting on an appropriate schedule can help, but the enclosure should not stay wet all the time. Too much moisture may raise the risk of mold, mites, or husbandry-related stress.

If your jumping spider stops eating, the cause is not always diet. Premolt, low temperatures, stress after rehoming, dehydration, and prey that is too large are all common reasons. If your spider seems weak, has trouble molting, or goes off food for longer than expected for its age and species, contact your vet with exotic animal experience.

There is no single number of insects that fits every jumping spider. Safe feeding depends on species, age, prey size, temperature, and body condition. In general, spiderlings often need small prey every 1-3 days because they are growing quickly. Juveniles may eat every 2-4 days, and many adults do well every 2-5 days. Females carrying eggs or recently matured spiders may have different appetites.

A better guide than a rigid schedule is the abdomen. A healthy jumping spider usually has an abdomen that looks gently rounded, not flat or wrinkled and not stretched tight. If the abdomen looks small or deflated, offer appropriately sized prey sooner. If it looks very full, wait longer before the next feeding. Overfeeding can increase the risk of falls from a heavy abdomen and may leave uneaten prey in the enclosure.

Remove uneaten insects, especially crickets, if your spider is not actively hunting. Loose prey can stress or injure a spider during rest or molt. For many pet parents, one or two suitable prey items per feeding is enough for an adult, while spiderlings may do better with several tiny prey items such as melanogaster or hydei fruit flies.

Feeder insect cost range is usually modest. Fruit fly cultures often cost about $8-$15 each, small cricket batches about $4-$10, and fly pupae or roach nymph starter amounts about $6-$18, with shipping sometimes adding more. Your vet can help you adjust feeding frequency if your spider is underweight, obese, dehydrated, or having molt issues.

Watch for changes in body shape, behavior, and hunting ability. A shrunken or wrinkled abdomen can point to underfeeding, dehydration, or illness. A spider that no longer tracks prey, misses easy strikes, stays curled, or spends unusual time on the enclosure floor may need prompt attention. Repeated refusal of food can be normal before a molt, but it should be interpreted in context.

Molting trouble is one of the biggest red flags. If a jumping spider is stuck in a molt, has deformed legs afterward, or seems unable to climb normally, husbandry and hydration may need review right away. Uneaten prey left in the enclosure during a molt can also be dangerous. Sudden weakness, inability to grip, or a very dark, collapsed-looking body are more urgent concerns.

See your vet immediately if your spider is severely lethargic, injured by prey, unable to right itself, or appears trapped in a bad molt. Contact your vet soon if appetite drops for an unusually long period, the abdomen keeps shrinking, or you notice mites, mold, or repeated feeding failures. Because normal fasting varies by age and species, your vet can help decide whether the pattern is expected or a sign of disease or husbandry stress.

Other warning signs include foul enclosure odor, visible pests, persistent dampness, or prey items that are too large and repeatedly harass the spider. These are often husbandry problems first, but they can quickly become health problems if not corrected.

If your jumping spider will not take one feeder insect, try another safe, captive-raised live prey option rather than forcing a meal. Good alternatives include flightless fruit flies for spiderlings, house flies or bottle flies for active hunters, and small roach nymphs for some larger species. Many jumping spiders respond better to flying or climbing prey than to worms left on the floor.

Mealworms and waxworms can be used cautiously for some larger spiders, but they are not ideal staples for many jumping spiders. They may be less stimulating to hunt, can burrow or hide, and some are relatively fatty compared with other feeders. Very large crickets are also poor choices because they can injure a spider, especially during a molt or overnight.

Avoid wild-caught insects, fireflies, ants, and chemically exposed household bugs. Wild prey may bring pesticides, parasites, or defensive chemicals. If you want better nutrition from feeder insects, focus on buying healthy feeder cultures and replacing them regularly. For insect species that can be gut-loaded, good feeder care may improve prey quality before feeding.

If your spider is a picky eater, your vet may suggest changing prey size, prey movement, enclosure setup, or hydration rather than changing species of food alone. The goal is not one perfect feeder insect. It is a safe, varied plan that matches your spider’s size, hunting style, and life stage.