Social Spider Colonies Can Die Off From Oversharing Food

Posted on August 5, 2016

Social spiders eating an insect

Social spiders are unique species of spiders that live together like ants and bees. The Anelosimus eximius social spider species lives in South America in huge colonies. They form the biggest spider nests in the world. The colonies can ultimately go extinct from oversharing food.

The spiders nest together and form one very large web. The nest and web gets bigger and bigger with successive generations. The size of the prey captured also increases with colony size. The downsize to this social spider species is the colonies can go extinct when they cannot capture enough prey.

Researchers from the University of British Columbia studied food sharing in the spiders. They say the sharing concept works well for the spiders until the colony grows too large and food becomes limited. The researchers - UBC PhD student Ruth Sharpe and UBC zoology professor Leticia Aviles - say they believe the problem occurs because "large colonies tend to capture prey that are too large for any one spider to monopolize."

Sharpe says in a statement, "We did this research to figure out why large, well-established colonies were going extinct so swiftly. Once I saw a massive nest on the side of the road in Ecuador, about five metres tall and four metres across. I went back a few weeks later and it was completely gone."

The research study was published here in the journal, Journal of Animal Ecology. Here is a video of a large nest created by social spiders:



Photo: UBC