This Spider Hunts With a Lasso

Most spiders hunt by spinning elaborate webs and patiently waiting for their prey to get caught in the sticky architecture. Bolas spiders do things a little differently.

These orbweavers use a sticky blob of silk on the end of a line known as a ‘bolas’ to capture prey. They swing the sticky lasso at nearby moths and flies, capturing them on the end of the line. The technique, which resembles a fisherman using a fishing line, has also earned them the nickname fishing or angling spiders.

The term ‘bolas’ comes from the Spanish word for a weapon made of several balls attached to a cord, which South American cowboys used to capture animals by entangling their limbs.

Bolas spiders actually consist of several different species from three related genera: American Bolas (Mastophora), African Bolas (Cladomelea) and Australasian Bolas (Ordgarius).

The blob of liquid on the end of their silk lasso is packed with pheromones that mimic female moths. When a male moth approaches, the spider quickly swings its lasso and captures it.

Typically, each spider species produces pheromones for only one type of moth species. But some bolas spiders have displayed the amazing ability to vary their methods for different types of moths, producing one type of pheromone during part of the day to attract one species, then switching to another at night to attract an entirely different species that would have been repelled by the first scent.

Watch one of these incredible spiders in action in the video below: