Spiders also make “scarecrows” out of larger spiders to scare off predators.

Scarecrows are made from prey carcasses and other materials and resemble larger spiders. Their purpose is to scare or distract predators, giving the spider time to escape.

A new publication in Ecology and Evolution has formally recorded, for the first time, a remarkable form of web decoration created by certain orb spiders: life-sized decoys that resemble larger spiders.

These intricate structures, known as stablehave been discussed for decades by arachnologists, but had never been scientifically confirmed until now, writes .

Stabilizers are structures of silk or debris incorporated into spider webs that perform various functions, from strengthening the web to signaling the arrival of prey. Previous research has suggested that the zigzag patterns in some webs could function like “bells,” transmitting vibrations to alert spiders to movement in wider areas of the web. But the recently described stabilizes go far beyond simple lines.

Scientists studying two geographically distant species of the genus Cyclosa have confirmed that these spiders build stabilizations using prey carcasses and plant materials to create shapes with a central “body” and five to eight “legs.” The result is a stunning imitation of a much larger spider, functioning as a silk scarecrow hanging in the center of the web.

Field observations were collected over a decade, starting with imagery from Peru in 2012 and followed by additional documentation in 2014 and 2022 at both locations. A careful analysis of the structures revealed that the baits served different defensive purposes for each species.

According to researchers, the Cyclosa species from the Philippines hides within its spider-like enclosure, using it as camouflage. When a predator approaches, the structure can mask the spider’s true location, allowing it to remain invisible until the threat passes.

In contrast, the Peruvian species sits just above the bait, appearing smaller than the elaborate structure beneath. This strategy can divert attention from predatorscausing them to focus on the larger, inanimate target, giving the real spider time to flee, abandoning the web.

The authors note that these “debris-weaving spiders” may benefit from an additional layer of defense: the structures sometimes resemble bird droppingswhich many predators avoid.

Despite progress in documenting these behaviors, researchers say there are still doubts. Why have these specific Cyclosa populations developed such sophisticated baits, while others have not? The team suggests that intense predation pressure in both environments may have driven the development of more complex visual defenses.