Black Widow Spiders Are Heading North Due to Climate Change

Black Widow Spiders
A pair of black widow spiders with an egg sack emerge from their spot on the banks of the Irtysh river near Pavlodar, Kazakhstan. The black widow spider’s venom is 15 times stronger than a rattlesnake’s. STRINGER/REUTERS

As climate change warms the earth, black widow spiders are moving north.

The spiders are notorious, because venom is 15 times stronger than a rattlesnake's. A bite can cause aches, pains, and paralysis of the diaphragm which make breathing difficult.

In a study published in PLOS One on Wednesday, Canadian researchers reported that over the past 60 years the northernmost point black widow spiders live has moved 31 miles north, into southern Canada. The scientists believe that the spread of the spiders, which prefer a temperate climate, is due to climate change.

The team used citizen data to make updated species distribution maps for the spider. "In our project, the citizen science data was essential in modeling distributions of spiders," Christopher Buddle, a co-author on the study and professor at McGill University, said in a statement. "People who are excited about discovering where species live can contribute in meaningful ways to scientific progress and this is exciting, important, and is changing how we do research."

The scientists hope that this will provide a new way for scientists to study species distribution, especially during a time when so many species are affected by changing climates. This style of collecting information is more efficient and less expensive than sending scientists out into the field and helps the researchers cover more ground.

The team also looked at the black purse-web spider and found the similar results as the black widow. The new maps are considered the first reliable maps for both species.