How to Identify & Get Rid of Spider Egg Sacs

When cleaning areas like basements, attics, or garages, you might discover small, silk-covered spheres in corners or behind furniture. These are likely spider egg sacs, which can contain dozens or even hundreds of spider eggs, depending on the species. Spider eggs are typically laid in these protective sacs to shield them from predators and environmental hazards. Understanding what they are and how to handle them is important for maintaining a safe and comfortable environment.

What do spider eggs look like?

Individual spider eggs are rarely seen, as they are almost always enclosed in silk egg sacs for protection. These sacs typically appear as small, white or cream-colored spheres. Inside, the eggs can look like tiny pearls or drops clustered together, with each sac containing between 30 and 300 eggs, depending on the species.

When do spiders lay eggs?

Most spiders lay eggs during warmer months, as higher temperatures and humidity create optimal conditions for survival. While timing varies by species, spring through early fall is typical. After the eggs are laid, they may take anywhere from several weeks to a few months to hatch, influenced by environmental conditions.

What do spider egg sacs look like?

Spider egg sacs display several traits that make them identifiable:

• Size: Typically about the same size as the spider that produced them, though some are larger or smaller.

• Shape: Most often round or oblong, but a few species may create flat or disk-shaped sacs.

• Color: Usually white or cream, but some may range from brown to off-white.

• Texture: Composed of silk, so they might feel smooth, bumpy, or slightly spiky.

• Layers: Often made with several layers of silk to provide protection.

However, not all spider egg sacs are created equal. Black widow sacs are small, spherical, and papery. Common house spiders prefer something about the size of a marble or pea, densely woven with silk. Brown recluse spiders keep it loose and off-white in concealed spots. The wolf spider is known for its unique maternal behavior, carrying its egg sac attached to its abdomen for protection.

Where do spiders lay egg sacs?

Spiders select locations that protect their eggs from predators and environmental harm. Indoors, they often deposit egg sacs in secluded areas like hidden room corners, behind or beneath furniture and appliances, inside closets, along basement and attic walls, or within their existing webs. Outdoors, preferred spots include under leaves, in tree bark crevices, within garden webs, beneath rocks or leaf litter, and attached to plant stems.

How to Tell if a Spider Egg Sac is Empty

You can tell if a spider egg sac is empty by its appearance and weight. An empty sac will often look deflated or have visible exit holes from where the spiderlings emerged. It will also be lightweight and move easily if disturbed by air. A full egg sac, on the other hand, will look more robust, maintain its shape, and feel heavier.

How to Remove Spider Egg Sacs

If you find spider egg sacs in your home, there are several safe removal methods:

Vacuum Removal (Recommended)

1. Use a vacuum cleaner with a hose attachment.

2. Carefully vacuum up the egg sac.

3. Dispose of the vacuum bag immediately in an outdoor trash bin.

4. If using a bagless vacuum, empty and clean the canister outdoors.

Manual Removal

1. Use a broom or long-handled tool for safety.

2. Gently dislodge or sweep up the egg sac.

3. Collect the sac and accompanying debris for outdoor disposal.

4. Clean the affected area.

Chemical Treatment

• Use a solution of water and bleach or an oil-based pesticide designed for spiders.

• Always carefully follow safety instructions on product labels.

Important: For potentially dangerous species such as black widows, professional pest control services are recommended to ensure safety.

Spider Prevention

To make your home less hospitable for spiders:

• Seal cracks and gaps around doors, windows, and foundations.

• Reduce clutter in storage areas to remove hiding places.

• Clean regularly to eliminate webs and potential nesting sites.

• Manage moisture by fixing leaks and using dehumidifiers.

• Maintain your home's exterior by trimming vegetation away from foundations.

When to Call an Exterminator

Sometimes, you just need to call in a Pro. If you're dealing with venomous spider species like black widows or brown recluses, facing a large infestation with multiple egg sacs, or if those sacs are tucked away in hard-to-reach spots, it's time for professional help. Orkin Pros have the knowledge and tools to safely and effectively manage spider infestations and help keep them from returning.

If you’re experiencing a spider infestation, contact an Orkin Pro for help with spider control.

More Spider Resources

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What is Spider Silk Made of?

Spider silk serves multiple purposes, from building webs and catching prey to creating egg sacs and shelters, each type of silk offering unique strength and flexibility.

What are the World's Deadliest Spiders?

Highlights some of the most dangerous spiders across the globe, detailing their venom potency, geographic range, and potential health risks to humans.

Do Natural Spider Repellents Work?

Certain scents like peppermint, citrus, and vinegar may help deter spiders, though these natural repellents are typically short-term solutions best used alongside other prevention methods.