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Northern Black Widow (Latrodectus variolus)

The Northern Black Widow is a cool spider found mainly on the ‘East Coast’ of North America. It’s a close relative to the southern and western black widows. Female spiders from this group are really strong and make amazing 3D webs out in nature. Ready to discover more about them? Keep reading!

Scientific Classification

Northern Black Widow

Physical Description and Identification

Adults

  • Size: Adult females are approximately 9-11 mm in length, and the males are 4-5 mm – that is, almost half the size of the former (both excluding legs).
  • Color: The characteristic hourglass mark in the Northern Black Widow is rather broken (unlike the female Southern Black Widow’s that has the hourglass mark distinct). Males have four diagonal whitish bands on each side of the abdomen.
  • Other Characteristic Features: Male black widows are not black, but are rather gray or brown with small red spots. Also, the males play their roles only for reproduction purposes and are mostly consumed by the females after mating or copulation.
Northern Black Widow Spider Size

Eggs

The females lay approximately up to 200 eggs that they incubate for around three weeks in a small, round, brown, papery sac that remains attached to the mother’s web.

Spiderlings

Like the males, the juveniles and immature specimens have two pairs of diagonal whitish bands on both sides of the abdomen. After hatching, the baby spiders remain in the cocoon for around four weeks. They are taken care of by the mother until they are mature enough to forage for themselves.

Are Northern Black Widow Spiders Venomous?

Yes, Northern Black Widow Spiders have venom. They use it mostly to catch the bugs they like to eat.

Can Northern Black Widow Spiders Bite?

While the venom of widow spiders is 15 times stronger than rattlesnakes’, they rarely bite as they are shy and prefer to run away when threatened. Even if bitten, the small amount of venom means it’s usually not deadly, with only a 1% mortality rate. Bites cause immediate pain, and redness, and can hurt for up to 24 hours.

Ecological Importance and Behavior of Northern Black Widow Spider

Northern Black Widows are important predators in their habitats. They control insect populations, which could otherwise become pests. Their impressive three-dimensional webs are not just for catching prey but also serve as protective structures for their offspring. They are shy by nature and exhibit remarkable maternal care.

Natural Predators: These spiders face predation from birds and larger spiders. This predation is a natural control on their populations, ensuring they do not become too numerous.

Prey-Predator Dynamics: The Northern Black Widow feeds primarily on insects but will also consume smaller spiders and arthropods. This diet makes them an integral part of the food web, controlling the insect population and providing food for their predators.

Relationship with Humans: While the Northern Black Widow’s venom is potent, they are timid and bites are rare. When they do occur, bites can be painful but are seldom fatal thanks to the small amount of venom injected. They prefer undisturbed natural habitats but can sometimes be found in human-inhabited areas, where their pest control benefits are welcomed.

Quick Facts

Other NamesNorthern widow
Lifespan1 to 3 years
DistributionRanges from northern Florida to south-eastern Canada
HabitatMostly prefer undisturbed woods, stumps, and stone walls
Common predatorsBirds of prey, larger spiders
DietMostly insectivorous, but might prey upon other smaller spider species and non-insect arthropods as well
Northern Black Widow Male

Did You Know

  • These arachnids have been compared to widows mourning in ‘black’ cloaks for the unique appearance of the females, and the tendency to eat their mates.

In conclusion, the Northern Black Widow is a species that, despite its fearsome reputation, contributes significantly to the ecological balance through its predatory habits.

Northern Black Widow Spider

The Northern Black Widow is a cool spider found mainly on the ‘East Coast’ of North America. It’s a close relative to the southern and western black widows. Female spiders from this group are really strong and make amazing 3D webs out in nature. Ready to discover more about them? Keep reading!

Northern Black Widow

Physical Description and Identification

Adults

  • Size: Adult females are approximately 9-11 mm in length, and the males are 4-5 mm – that is, almost half the size of the former (both excluding legs).
  • Color: The characteristic hourglass mark in the Northern Black Widow is rather broken (unlike the female Southern Black Widow’s that has the hourglass mark distinct). Males have four diagonal whitish bands on each side of the abdomen.
  • Other Characteristic Features: Male black widows are not black, but are rather gray or brown with small red spots. Also, the males play their roles only for reproduction purposes and are mostly consumed by the females after mating or copulation.
Northern Black Widow Spider Size

Eggs

The females lay approximately up to 200 eggs that they incubate for around three weeks in a small, round, brown, papery sac that remains attached to the mother’s web.

Spiderlings

Like the males, the juveniles and immature specimens have two pairs of diagonal whitish bands on both sides of the abdomen. After hatching, the baby spiders remain in the cocoon for around four weeks. They are taken care of by the mother until they are mature enough to forage for themselves.

Are Northern Black Widow Spiders Venomous?

Yes, Northern Black Widow Spiders have venom. They use it mostly to catch the bugs they like to eat.

Can Northern Black Widow Spiders Bite?

While the venom of widow spiders is 15 times stronger than rattlesnakes’, they rarely bite as they are shy and prefer to run away when threatened. Even if bitten, the small amount of venom means it’s usually not deadly, with only a 1% mortality rate. Bites cause immediate pain, and redness, and can hurt for up to 24 hours.

Ecological Importance and Behavior of Northern Black Widow Spider

Northern Black Widows are important predators in their habitats. They control insect populations, which could otherwise become pests. Their impressive three-dimensional webs are not just for catching prey but also serve as protective structures for their offspring. They are shy by nature and exhibit remarkable maternal care.

Natural Predators: These spiders face predation from birds and larger spiders. This predation is a natural control on their populations, ensuring they do not become too numerous.

Prey-Predator Dynamics: The Northern Black Widow feeds primarily on insects but will also consume smaller spiders and arthropods. This diet makes them an integral part of the food web, controlling the insect population and providing food for their predators.

Relationship with Humans: While the Northern Black Widow’s venom is potent, they are timid and bites are rare. When they do occur, bites can be painful but are seldom fatal thanks to the small amount of venom injected. They prefer undisturbed natural habitats but can sometimes be found in human-inhabited areas, where their pest control benefits are welcomed.

Quick Facts

Other NamesNorthern widow
Lifespan1 to 3 years
DistributionRanges from northern Florida to south-eastern Canada
HabitatMostly prefer undisturbed woods, stumps, and stone walls
Common predatorsBirds of prey, larger spiders
DietMostly insectivorous, but might prey upon other smaller spider species and non-insect arthropods as well
Northern Black Widow Male

Did You Know

  • These arachnids have been compared to widows mourning in ‘black’ cloaks for the unique appearance of the females, and the tendency to eat their mates.

In conclusion, the Northern Black Widow is a species that, despite its fearsome reputation, contributes significantly to the ecological balance through its predatory habits.

Northern Black Widow Spider