The Black Widow Spider is a carnivorous spider. It often preys on insects such as wood lice, diplopods, chilopods, and arachnids. Although these are the most common choices of prey, Lactodectus sp. have been known to prey on many different types of victims, from large to small, fast to slow, and poisonous and non-poisonous. They will eat anything that they can successfully catch and then kill. This usually includes insects, but can sometimes include small reptiles, birds, and mammals.

When an insect lands on the Black Widow’s web, the spider can feel the vibrations and will immediately start to wrap its prey with its silk webbing. The Latrodectus sp. will then bite its prey and inject venom into the insect with its fangs. This venom is 15 times stronger than that of a rattlesnake, so it works very quickly. At this point, the spider drags the prey to its sheltered home. When the Black Widow’s victim stops moving, the spider then uses its cheliceral teeth to chew and mash up the original wound site. After that, this site is used for the Latrodectus sp. to pour its digestive enzymes in to. The spider then sucks up the food within its prey’s body. The whole digestive process takes place outside of the spider's body.

black widow spider, Latrodectus mactans  (Araneae: Theridiidae) - 5389207

Figure 1. Black Widow Spider and prey.

The Black Widow has the ability to consume a lot of food, but can also go for long periods of time without it. In lab experiments scientists have found that on average a spider can survive three to four months without food. One spider, although greatly weakened, survived 9 months before being replenished and brought back to health. This showed that the Latrodectus sp. can acclimate to almost any food abundance. They will eat a large amount when it is available to them, and when there is very little available, they conserve their energy.