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Barn (Araneus cavaticus)

Have you ever seen a Barn spider? This spider loves to weave its webs at night and is found mostly in North America. You’ll see them a lot in late summer and autumn. Keep reading, and we’ll share some fun facts about this nighttime weaver!

Scientific Classification

Barn Spider

Physical Description and Identification

Adults

  • Size: They exhibit sexual dimorphism when it comes to size as the females who are 0.47 inches to 0.62 inches (12 mm to 16 mm) long are bigger than their male counterparts that are 0.23 inches to 0.39 inches (6 mm to 10 mm).
  • Color: These spiders are yellow or brown, with grey or dark stripes on their legs. The lower part of their body is black with white markings.
  • Other characteristic features:  The Barn spider has a hairy body alongside a big, round-shaped abdomen with numerous small humps.
Barn Spider Size

Eggs

The egg sac made using silken thread resembles a cocoon. A single sac has hundreds of eggs within that are round or disc-shaped.

Spiderlings

Though not much is known about the size of the spiderlings, they get on their own within a short span after hatching.

The Web

Being orb weavers, their webs are flat and spiral-shaped, made of sticky and less sticky threads to capture prey and support the structure of the web respectively. The webs are mostly spun by the females, who take it down in the day and build a new one every evening. At night they wait in the middle of the web to attack any prey that enters it.

Barn Spider Web

Are Barn Spiders Venomous?

Yes, Barn Spiders are venomous. They use their venom to catch their meals, but it’s not very strong for humans.

Can Barn Spiders Bite?

Yes, Barn Spiders can bite. They’re usually busy with their webs, but if they do bite, it feels like a small pinch and isn’t dangerous for most people.

Barn Spider Bite

Ecological Importance and Behavior of Barn Spider

Barn Spiders are integral to controlling insect populations. They prey on a variety of insects, including beetles, ants, moths, flies, and mosquitoes, which benefits agricultural and garden environments by reducing pest numbers. Their nocturnal web-weaving and hunting behaviors are essential for the balance of the local ecosystems.

Natural Predators: Natural predators of Barn Spiders include birds and other spiders, which help keep their populations in check and prevent overpopulation that could disrupt ecological stability.

Prey-Predator Dynamics: The interplay between Barn Spiders and their prey is a classic example of a predator-prey relationship. They aid in controlling the insect population, thereby influencing the health of their habitat. Simultaneously, they provide sustenance for their predators, illustrating the cycle of energy within their ecosystem.

Relationship with Humans: Barn Spiders are generally harmless to humans. Their venom, while effective on small insects, causes only mild discomfort to people, akin to a slight pinch, with bites being rare. They are often found in human-made structures like barns and sheds, where they contribute to insect control.

Araneus Cavaticus

Quick Facts

LifespanApproximately one year
DistributionNortheastern parts of the United States and Canada
HabitatWooden structures like rafters, barns, and even boats
PredatorsBirds and other spiders
DietSeveral insects like beetles, ants, moths, flies and mosquitoes
Barn Spider Image

Did You Know

  • The Barn Spider rose to prominence in E.B. White’s Charlotte’s Web where it was called Charlotte A. Cavatica, the last name corresponding to its scientific name.
  • Like all other spiders, they too catch the prey by sensing their vibrations as these creatures have poor eyesight.

In conclusion, the Barn Spider is an ecologically valuable species, serving as both predator and prey.

Araneus Cavaticus Picture

Have you ever seen a Barn spider? This spider loves to weave its webs at night and is found mostly in North America. You’ll see them a lot in late summer and autumn. Keep reading, and we’ll share some fun facts about this nighttime weaver!

Barn Spider

Physical Description and Identification

Adults

  • Size: They exhibit sexual dimorphism when it comes to size as the females who are 0.47 inches to 0.62 inches (12 mm to 16 mm) long are bigger than their male counterparts that are 0.23 inches to 0.39 inches (6 mm to 10 mm).
  • Color: These spiders are yellow or brown, with grey or dark stripes on their legs. The lower part of their body is black with white markings.
  • Other characteristic features:  The Barn spider has a hairy body alongside a big, round-shaped abdomen with numerous small humps.
Barn Spider Size

Eggs

The egg sac made using silken thread resembles a cocoon. A single sac has hundreds of eggs within that are round or disc-shaped.

Spiderlings

Though not much is known about the size of the spiderlings, they get on their own within a short span after hatching.

The Web

Being orb weavers, their webs are flat and spiral-shaped, made of sticky and less sticky threads to capture prey and support the structure of the web respectively. The webs are mostly spun by the females, who take it down in the day and build a new one every evening. At night they wait in the middle of the web to attack any prey that enters it.

Barn Spider Web

Are Barn Spiders Venomous?

Yes, Barn Spiders are venomous. They use their venom to catch their meals, but it’s not very strong for humans.

Can Barn Spiders Bite?

Yes, Barn Spiders can bite. They’re usually busy with their webs, but if they do bite, it feels like a small pinch and isn’t dangerous for most people.

Barn Spider Bite

Ecological Importance and Behavior of Barn Spider

Barn Spiders are integral to controlling insect populations. They prey on a variety of insects, including beetles, ants, moths, flies, and mosquitoes, which benefits agricultural and garden environments by reducing pest numbers. Their nocturnal web-weaving and hunting behaviors are essential for the balance of the local ecosystems.

Natural Predators: Natural predators of Barn Spiders include birds and other spiders, which help keep their populations in check and prevent overpopulation that could disrupt ecological stability.

Prey-Predator Dynamics: The interplay between Barn Spiders and their prey is a classic example of a predator-prey relationship. They aid in controlling the insect population, thereby influencing the health of their habitat. Simultaneously, they provide sustenance for their predators, illustrating the cycle of energy within their ecosystem.

Relationship with Humans: Barn Spiders are generally harmless to humans. Their venom, while effective on small insects, causes only mild discomfort to people, akin to a slight pinch, with bites being rare. They are often found in human-made structures like barns and sheds, where they contribute to insect control.

Araneus Cavaticus

Quick Facts

LifespanApproximately one year
DistributionNortheastern parts of the United States and Canada
HabitatWooden structures like rafters, barns, and even boats
PredatorsBirds and other spiders
DietSeveral insects like beetles, ants, moths, flies and mosquitoes
Barn Spider Image

Did You Know

  • The Barn Spider rose to prominence in E.B. White’s Charlotte’s Web where it was called Charlotte A. Cavatica, the last name corresponding to its scientific name.
  • Like all other spiders, they too catch the prey by sensing their vibrations as these creatures have poor eyesight.

In conclusion, the Barn Spider is an ecologically valuable species, serving as both predator and prey.

Araneus Cavaticus Picture