What to Do When a Jumping Spider Refuses Food

A jumping spider refusing a meal can be worrying, especially if you are used to seeing it actively stalk and pounce on feeders.

But food refusal is not a diagnosis by itself.

Jumping spiders may stop eating for several very different reasons, including premolt, recent feeding, prey preference, environmental conditions, maturity, or simply because the offered feeder is not appealing to that individual.

The most useful approach is to look at the spider’s overall behavior and condition, not just whether it ate today.

First: Do Not Panic Over One Refused Meal

A healthy jumping spider does not necessarily eat every time food is offered.

Spiders are adapted to intermittent prey availability, and hunger changes their motivation to forage. Experimental work with jumping spiders has shown that food-restricted individuals tend to become more active in searching for prey and can initiate hunting more quickly.

So one refused feeder does not automatically indicate that something is wrong.

Before changing anything, look at:

• Abdomen condition
• Activity level
• Whether the spider is using its hammock more than usual
• Whether it appears to be approaching a molt
• The size and type of prey offered
• Temperature and general enclosure conditions
• Whether it recently ate a substantial meal

Reason 1: Your Spider May Be Preparing to Molt

Premolt is one of the most important explanations for sudden food refusal.

A spider approaching a molt may:

• Spend more time in its silk retreat
• Build or thicken its hammock
• Become less active
• Stop actively hunting
• Refuse feeders it normally accepts

If those behaviors occur together, avoid repeatedly disturbing the spider or trying to force a feeding response.

Remove Uneaten Prey

Do not leave potentially troublesome live prey in the enclosure with a spider that may be molting.

Molting spiders are vulnerable, and the new exoskeleton remains soft immediately after emergence.

The safest approach is to remove uneaten prey and allow the spider to complete the molt undisturbed.

Reason 2: It May Simply Not Be Hungry

If the spider recently ate and its abdomen remains comfortably filled, another meal may not be necessary yet.

Avoid interpreting feeding schedules as rigid deadlines.

Individual jumping spiders vary in:

• Metabolism
• Meal size
• Activity
• Age
• Sex
• Reproductive state
• Environmental conditions

A feeding schedule is a husbandry guideline, not a requirement that the spider eat on command.

Use Abdomen Condition as Context, Not a Formula

The abdomen can provide useful information about feeding condition.

A recently fed spider will often have a fuller abdomen than one that has not eaten for some time.

Research supports the broader relationship between nutritional state and spider body condition, but there is no scientifically validated universal rule such as:

“Feed when the abdomen is exactly this percentage of the carapace.”

So use abdominal fullness as one piece of information rather than a precise diagnostic measurement.

Reason 3: The Spider May Not Like That Feeder

Jumping spiders are highly visual predators, and prey choice can be surprisingly specific.

Research on salticids shows that some jumping spiders distinguish between prey categories and can develop or possess strong preferences for particular kinds of prey.

That means a spider refusing one feeder does not necessarily mean it is refusing food altogether.

For example, a jumper might ignore:

• A mealworm

but immediately pursue:

• A fruit fly
• House fly
• Blue Bottle Fly

Movement, size, shape, and prey type can all influence the hunting response.

Flies Can Be Especially Stimulating

Jumping spiders hunt primarily using excellent vision.

Active flying prey can provide strong visual stimulation and may trigger hunting behavior more effectively than slower prey in some individuals.

This is one reason flies are such useful feeders for many jumpers.

Depending on the spider’s size, options include:

• Drosophila melanogaster for small slings
• Drosophila hydei for larger slings and juveniles
• House flies for larger juveniles and adults
• Blue Bottle Flies for larger, confident jumpers

If a healthy, alert spider ignores one prey type, trying a different appropriately sized feeder can be reasonable.

Reason 4: The Feeder May Be Too Large

Prey size affects hunting decisions.

Research shows that size preference is not governed by one universal ratio. Smaller jumping spiders may favor smaller prey, while larger individuals may take larger prey, and strong prey preferences can sometimes override size preference.

This is why rigid statements such as:

“A feeder must always be exactly two-thirds the spider’s size”

are too simplistic.

Instead, watch the spider.

Signs the prey may be intimidating include:

• Retreating from it
• Repeated avoidance
• Hiding
• Defensive behavior
• Tracking the prey but refusing to approach

If you are unsure, offer something smaller.

Reason 5: The Feeder May Be Too Small or Uninteresting

The opposite can happen too.

A larger spider may show little interest in extremely tiny prey.

The feeder may be perfectly edible but not provide enough movement or visual stimulus to trigger a strong hunting response.

Moving up to a larger but still appropriate prey item may help.

Again, observe the spider rather than relying entirely on a size chart.

Reason 6: It May Be a Mature Male

Mature males can behave differently from juveniles and females.

Once mature, males may devote substantial time and energy to:

• Exploring
• Searching
• Courtship behavior
• Responding to potential mates

Reproductive behavior can compete with feeding and other activities.

So a mature male that becomes more restless and less interested in food may not necessarily be experiencing the same issue as a juvenile that suddenly stops eating.

That does not mean every mature male stops eating. It means maturity is useful context when interpreting behavior.

Reason 7: Environmental Conditions May Be Affecting Behavior

If the spider is refusing multiple appropriate feeders, evaluate the enclosure.

Check:

• Temperature
• Ventilation
• Hydration opportunities
• Lighting
• Excessive disturbance
• Recent enclosure changes

Jumping spiders rely heavily on vision for hunting, so normal light conditions are particularly relevant to prey detection and recognition. Research on salticids demonstrates sophisticated visual prey discrimination.

Avoid placing the enclosure in direct sunlight or exposing it to extreme heat while trying to “encourage” feeding.

Reason 8: The Spider May Be Stressed

Recent changes can temporarily affect behavior.

Possible examples include:

• Shipping
• Moving into a new enclosure
• Rehousing
• Excessive handling
• Repeated enclosure disturbance

A recently rehoused spider may spend time establishing a retreat and becoming accustomed to its surroundings before behaving normally.

Give it appropriate conditions and some time rather than continually introducing new prey.

Hunger Usually Increases Foraging Motivation

One reason prolonged refusal deserves more attention than a single skipped feeding is that hunger generally increases motivation to find food.

In controlled research, food-restricted jumping spiders spent more time outside their nests, detected prey more rapidly, began hunting sooner, and showed increased capture success.

So if a spider continues losing condition while remaining uninterested in multiple appropriate prey types, it is worth looking beyond the idea that it is simply “not hungry.”

Prey Choice Can Change With Nutritional State

Hunger does not necessarily eliminate selectivity.

Research on jumping spiders shows that nutritional condition can influence prey choice and foraging decisions.

So feeding behavior is more complicated than:

Hungry = attacks anything.

A spider can be motivated to feed while still evaluating prey.

What Should You Try?

If your spider is alert, not obviously in premolt, and appears ready to hunt, try this progression.

1. Remove the refused feeder

Do not leave prey wandering around indefinitely.

2. Wait and try again later

Repeatedly presenting prey every few minutes may create unnecessary disturbance.

3. Try a smaller feeder

If the spider seemed intimidated, reduce the prey size.

4. Try a different type of feeder

A spider ignoring a mealworm may respond to a fly.

5. Observe instead of forcing interaction

Give the spider an opportunity to notice and approach prey naturally.

A Simple Troubleshooting Guide

Spider is in a thick hammock and refuses food

Possible explanation: Premolt.

Remove uneaten prey and minimize disturbance.

Spider has a very full abdomen and refuses food

Possible explanation: It may simply not need another meal yet.

Give it time.

Spider is alert and tracks prey but backs away

Possible explanation: The feeder may be too large or intimidating.

Try something smaller.

Spider ignores a mealworm but actively tracks flies

Possible explanation: Prey preference or movement may matter.

Try an appropriately sized flying feeder.

Mature male is constantly roaming and eating less

Possible explanation: Reproductive and mate-searching behavior may be influencing feeding.

Continue monitoring overall condition.

Spider repeatedly refuses multiple prey types and is becoming thinner

Possible explanation: This deserves closer investigation.

Review husbandry and environmental conditions rather than continuously cycling through feeders.

When Should Food Refusal Become More Concerning?

There is no scientifically defensible universal rule such as:

“A jumping spider must eat every X days.”

Different spiders can tolerate different fasting periods depending on:

• Age
• Size
• Sex
• Previous feeding
• Molting stage
• Reproductive condition
• Environmental conditions

Instead, look for a combination of warning signs.

More concerning situations include:

• Progressive abdominal shrinkage
• Weakness
• Loss of coordination
• Difficulty climbing
• Abnormal posture
• Persistent inactivity unrelated to apparent premolt
• Repeated refusal of several appropriate prey types
• Other clear deterioration in condition

At that point, investigate husbandry carefully and consider seeking help from an experienced exotic-invertebrate keeper or qualified veterinary professional familiar with arachnids.

Do Not Force-Feed a Jumping Spider

Routine food refusal is not a reason to physically force prey or liquids into a spider's mouthparts.

Force-feeding can create additional risk and stress.

The first response should be to determine why the spider is not feeding.

What About Honey or Sugar Water?

There is interesting scientific research showing that some jumping spiders can use carbohydrate sources.

For example, research with Phidippus audax found measurable benefits when spiders consuming live prey also had access to a sucrose solution under controlled experimental conditions.

However, that does not establish honey or sugar water as a general treatment for a pet jumping spider that refuses food.

We therefore do not recommend treating unexplained food refusal by improvising sugar or honey solutions.

Keep the Question Simple

When a jumper refuses food, ask:

What else is the spider telling me?

Look at:

• Is it preparing to molt?
• Did it recently eat?
• Is the abdomen already full?
• Is the prey appropriately sized?
• Does it respond differently to another prey type?
• Is it a mature male?
• Is the enclosure appropriate?
• Is its overall condition stable?

The answer is usually more informative than the refusal itself.

The Bottom Line

Jumping spiders do not eat according to a rigid calendar, and refusing one feeder does not automatically mean something is wrong.

Food refusal can occur because of:

• Premolt
• Recent feeding
• Prey preference
• Prey size
• Maturity
• Environmental conditions
• Temporary stress

Start by observing the spider.

If it appears healthy and well-conditioned, give it time and try an appropriate feeder later.

If it is interested in hunting but not in the particular prey offered, try another suitable feeder type or size.

If food refusal continues alongside progressive loss of condition or abnormal behavior, investigate further rather than assuming the spider is simply being picky.

The goal is not to make a jumping spider eat on schedule.

The goal is to understand its behavior well enough to recognize when not eating is normal—and when it may indicate something needs attention.