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Dolomedes vittatus

The Dolomedes vittatus belongs to the nursery web spiders family. These spiders have a cool talent: they can glide across water in search of their next meal. Get ready to explore fascinating facts about them right here!

Table Of Content hide

Physical Description and Identification

Are Dolomedes vittatus Spiders Venomous?

Can Dolomedes vittatus Spiders Bite?

Ecological Importance and Behavior of Dolomedes vittatus

Quick Facts

Did You Know

Photo Credit: Barb Sendelbach

Physical Description and Identification

Adults

Size: These spiders can grow quite large, with some reaching up to 7.6 cm (3 inches).

Photo Credit: Ben Springer

Color: They are either medium brown or black with white trim lines sometimes running down their side. There are white dots on the abdomen and two dark triangular marks on the cephalothorax.
Other Characteristic Features: Only the males have white stripes along the edges across their carapace and abdomen.

Eggs

Like other members of their genus, they produce a sac in which they lay their eggs.

Spiderlings

The spiderlings resemble tiny adults. Their mother stays in the nursery with them for a few days before leaving them to fend for themselves.

The Web

They generate webs in an irregular fashion.

Are Dolomedes vittatus Spiders Venomous?

Yes, Dolomedes vittatus spiders are venomous, but their venom is mostly harmless to humans and is used to subdue their prey.

Can Dolomedes vittatus Spiders Bite?

Yes, they can bite if threatened or provoked. However, their bite is typically not harmful to humans, causing only mild discomfort.

Photo Credit: Barb Sendelbach

Ecological Importance and Behavior of Dolomedes vittatus

Dolomedes vittatus spiders serve an important ecological function by controlling the population of aquatic insects, prawns, and even small fish. Their behavior includes a remarkable hunting technique where they utilize the surface tension of water to glide swiftly in pursuit of prey.

Natural Predator: These spiders, despite their venomous defense, are prey to birds, fish, and larger predators that share their aquatic habitat.

Prey-Predator Dynamics: The Dolomedes vittatus represents an integral part of the food web, acting as both a predator to smaller aquatic creatures and prey to larger animals. This dynamic is crucial for the balance of the ecosystems they inhabit.

Relationship with Humans: Human encounters with Dolomedes vittatus spiders are typically rare and non-threatening. While they are capable of biting, such instances are uncommon and the effects are minimal, resulting in little more than slight discomfort.

Photo Credit: Ben Springer

Quick Facts

Lifespan	2 years
Distribution	The United States
Habitat	Creek, river, and stream banks
Diet	Aquatic insects, prawns, and fish

Did You Know

French scientist Baron Charles Athanase Walckenaer first described this species in 1837.

In essence, the Dolomedes vittatus plays a significant role in its aquatic environment, contributing to the biodiversity and ecological stability of its habitat.

Frequently Asked Questions

How can you identify a Dolomedes vittatus spider?

You can identify a Dolomedes vittatus by its size and distinct markings. These spiders are medium brown or black with white trim lines, white abdominal dots, and two dark triangular marks on their cephalothorax. Males are distinguished by white stripes running along their carapace and abdomen.

How large can a Dolomedes vittatus spider grow?

A fully grown Dolomedes vittatus spider can become quite large, reaching a size of up to 7.6 cm (3 inches), including its leg span. This considerable size makes them one of the more noticeable nursery web spiders found near aquatic environments where they typically hunt for prey.

What do Dolomedes vittatus spiders eat?

Dolomedes vittatus spiders primarily eat aquatic insects, prawns, and occasionally even small fish. They play a key ecological role by helping to control these populations in their freshwater habitats. Their diet consists of prey they can subdue while hunting on or near the water’s surface.

How do Dolomedes vittatus spiders walk on water?

Dolomedes vittatus spiders glide across water by utilizing its surface tension. This remarkable ability allows them to move swiftly across ponds and streams to hunt prey without sinking. Their specialized legs and body posture distribute their weight, enabling them to effectively skate on the water’s surface.

Are Dolomedes vittatus spiders venomous to people?

Yes, Dolomedes vittatus spiders are venomous, but their venom is considered mostly harmless to humans. A bite is rare and typically only occurs if the spider is provoked, causing only mild discomfort. The venom’s primary function is to subdue their prey, not for defense against people.

Why do male Dolomedes vittatus look different from females?

Male Dolomedes vittatus spiders look different from females due to sexual dimorphism in their markings. While both sexes are brown or black, only the males possess distinct white stripes that run along the edges of their carapace and abdomen, making them visually distinguishable from their female counterparts.

How does a Dolomedes vittatus care for its young?

A female Dolomedes vittatus cares for her young by first creating a protective egg sac. After the spiderlings hatch, she remains with them in the nursery web for a few days. This brief period of maternal care helps ensure their initial survival before she leaves them to live independently.

Dolomedes vittatus