Insect Face-off: Do Cockroaches Eat Spiders- Discover Now

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Although cockroaches can survive without eating food for a long time, they always search for food, water, and shelter. They can eat anything available to them, from sweets to tiny pesky pests in your home. So, now the question is; do cockroaches eat spiders?

No, cockroaches don’t eat spiders. But they can feed spiders when they have nothing to eat. Throughout their life cycle, cockroaches don’t consume other insects; instead, they only consume foods made from natural sources, such as plants or animals.

Do you want to know more about cockroach eating habits? If so, stay in touch till the end of the article to learn about roaches & spiders.

Cockroaches V/S Spiders

Even though both cockroaches and spiders belong to the pests group, they have different body anatomy. Below are the key similarities and differences between roaches and spiders.

  • Both spiders and cockroaches cause trouble and nuisance in your home and properties.
  • Cockroaches have spiracles for breathing, while spiders use lungs for breathing.
  • Both spiders and roaches terrify people and cause allergies.
  • According to the Journal Nature Communications, cockroaches have more horrifying effects on people than spiders.
  • Similar to cockroaches, spiders prefer to live in dark spots.
  • Compared to spiders, cockroaches don’t have wings, so they can’t fly.
  • Moreover, cockroaches use antennae to sense or feel things, but spiders lack such a structure in their bodies.
  • Additionally, spiders are more in number on earth than cockroaches.

Are Cockroaches More Likely to Eat Spiders?

No, cockroaches don’t prefer eating spiders. However, they can consume them when they are in dire need of eating something or when they have nothing to feed. The point to be noted is that when they are hungry, roaches don’t actively seek spiders, but if they come into contact with a dead spider, they can rip its bones apart to obtain nutrition.

Furthermore, cockroaches are exclusively drawn to dead spiders since they don’t hunt down other insects and consume them to meet their energy needs. Hence, when cockroaches are hungry, they first go for food in the kitchen. Thus, you shouldn’t leave food in your kitchen unattended because cockroaches can smell it and may invade your kitchen.

Can a Spider Eat a Cockroach?

Yes, a spider can eat cockroaches. However, all spiders don’t eat cockroaches, some cockroaches, like jumping spiders, American house spiders, and huntsman spiders, love to consume roaches. These spider species are large, swift, and powerful enough to capture and destroy cockroaches.

Thus, it makes having a spider in your home advantageous for natural pest management, especially if you have a modest cockroach problem.

 Jumping spiders are smaller in size than cockroaches, but they eat them only when they are starving. Even though many spiders consume cockroaches, some do not because they are too little to do so. These include tiny household spiders because their jaws are too small to do so.

Nutritional Constitutes of Spiders

According to the Cambridge Physiological Society, cockroaches have been on the earth for 400 million years. As nutrition is essential for cockroaches, spiders offer the following nutrients to roaches.

  • Spiders have 16% fat and 126% proteins in their body. Thus, cockroaches eat them to fulfill their protein requirements.
  • Further, for growing cockroaches, protein is an essential factor for the synthesis of new cells, tissues, and enzymes.
  • Aside from that, protein is vital for several reactions in roaches’ bodies.
  • Thus, spiders are good and healthy options for cockroaches to eat when they have nothing.

Spiders That Are Dangerous to Cockroaches

Although cockroaches don’t consume living spiders, some dead spiders can still be harmful to them. They eat spiders, but some of them are deadly and can harm both humans and cockroaches. Below are some dangerous species of spiders to roaches.

  • Brazilian Wandering Spiders: They contain highly toxic venom that is deadly for cockroaches.
  • Red Spiders: Although less toxic than Brazilian species, they cause cell and tissue death in cockroaches.
  • Brown Spiders: They cause nausea and lethargy in cockroaches that eat them.
  • Black House Spiders: Though less harmful than other species, they may cause nausea and swelling in roaches.
  • Funnel-Web Spiders: These are highly toxic spiders, and cockroaches die immediately after consuming them.

Facts About Cockroach-Eating Spiders

Cockroaches are the most common household pests. Seeing them in the house is not a pleasant thing and causes a horrifying effect. But do you know; they have some notable attributes that make them curious pests? Some of the facts about roaches are mentioned below:

Quick Facts

  • About 4000 species of cockroaches exist in the world.
  • Most spider-eating cockroaches love to stay hidden from the eyes.
  • An important indication of such cockroaches is that they have a large size compared to other roaches.
  • Such cockroaches used to move quickly from one place to other.
  • They used to live in warm and humid areas of your house.
  • Moreover, cockroaches can live without their head for almost one week.
  • They have a hard and powerful exoskeleton.
  • Above all, they can survive underwater for about 40 minutes.

Survival of Cockroach-Eating Spiders

As cockroaches are adaptable, they can live for a fair amount of time without food, water, oxygen, or even their heads. Here are some key factors that help in their survival. 

  • Diet: Cockroaches eat anything available to them like starch and meat products. Moreover, they can also eat cheese and starch in your books for survival.
  • Adaptability: They are highly adapted creatures and can survive almost every situation.
  • Size: Because cockroaches have small sizes, they can pass through even a minute gap to find shelter.
  • Nocturnal: The fact that cockroaches used to hide during the day helps to protect them from predators.
  • Variations: Although all cockroaches have the same characteristics, some can survive for days without food and water.

Types of Cockroaches That Eat Spiders

German and American cockroaches are the most prevalent cockroaches that live in your homes, consume your food, eat dead spiders, and transmit diseases.

German Cockroach

Here are some characteristics of spider eating- German cockroaches:

  • Compared to other species, they have a small size.
  • They have two broad lines on their body and range in color from brown to black.
  • If food is scarce, these cockroaches can feast on dead spiders.
  • Most of the nutrition that German cockroaches consume come from the food that is kept in your kitchens.
  • Moreover, they used to find in your bathrooms and drainage pipes to stay hydrated.

American Cockroach

  • American cockroaches are similar in size to German cockroaches, except they are a little bit longer.
  • They like to consume foods similar to what humans eat, but they also eat the dead skeletons of spiders.
  • Additionally, they can follow you by slipping inside your bags and accessory boxes.
  • They infiltrate your home through bathroom pipes and reside in tiny crevices and cracks in the walls.
  • Above all, they enjoy hiding in dark areas of your house, like basements and attics.

Main Predators of Cockroaches

Cockroaches play an important role in our ecosystem. While some insects perish naturally, many more contribute to the food chain by serving as prey for cockroach predators. Here are the most common predators of cockroaches:

Outdoor Predators

  1. Amphibians, including toads and frogs.
  2. Mammals like mice and rats.
  3. Arachnids, including beetles, spiders, wasps, and other insects.

Indoor Predators

  1. Beetle Larvae
  2. Silverfish
  3. Cockroaches

What Other Insects Do Cockroaches Eat?

Although cockroaches can eat anything available to them, they consume dead insects when they have nothing to eat. In addition to bed bugs and their eggs, they are known to feed other pests as well. These critters devour both alive and dead insects.

Some cockroaches even consume their kind. Cockroaches from Asia, like the Orientals and Germany, consume their dead. When food supplies are limited, some cockroaches have been observed eating their eggs and nymphs. Moreover, some American cockroach females may devour and kill their partners.

Bottom Line

Even though cockroaches are highly flexible pests, they eat spiders only when they have no other option to feast. Cockroaches that eat spiders have some distinguishable characteristics, including their survival rate and eating habits.

Although spiders are less irritating than cockroaches, having them in your home for a long time could be dangerous. So, if you have spider-eating cockroaches, like German and American cockroaches, they may ward them off by consuming them.

Hopefully, the above details have cleared your doubts regarding cockroach eating habits. Above all, if you have an extensive spider and cockroach infestation in your home, take help from an expert pest control company.


Grimaldos, J., Duque, A., Palau-Batet, M. et al. Cockroaches are scarier than snakes and spiders: Validation of an affective standardized set of animal images (ASSAI). Behav Res53, 2338–2350 (2021).

AUTHOR=Tan Huaxin, Liu Sisi, He Yaolin, Cheng Guofeng, Zhang Yu, Wei Xiaojie, Hu Lidan, TITLE=Spider Toxin Peptide-Induced NIR Gold Nanocluster Fabrication for GSH-Responsive Cancer Cell Imaging and Nuclei Translocation, JOURNAL=Frontiers in Bioengineering and Biotechnology, VOLUME=9, YEAR=2021