Scientists working in the protected forests of Tambopata National Reserve were amazed when, in December 2012, they came across what looked like the lifeless body of a spider they had never seen before, laying in its own web.
Indeed, they certainly had discovered a species of arachnid previously unknown to science, but that is not what they first saw. In fact, what the scientists were looking at on that forest trail they were exploring was a decoy. They had stumbled across a species of tiny spider, around just 5 millimeters in length, which builds a decoy that looks like a much larger spider!
There are known to be at least 3600 species of spiders that are endemic to the Amazon basin, and so perhaps it was not all that surprising that a species new to science was discovered in the extraordinarily biodiverse forests of Tambopata, which rank as among the best-preserved areas of Amazon rainforest found anywhere on the South American continent. Other so-called “decoy spiders” were known to exist in other forests around the world, including the Philippines and Taiwan, but this was the first time one had been identified in the Amazon forests of Peru.
What this decoy spider does is quite remarkable, even when compared to the extraordinary behaviors of many other species of animals, insects and birds that inhabit the forests of the Amazon. Using leaves, vegetation debris, the carcasses of its prey, and even its own shed skin, this tiny but resourceful arachnid creates a sculptural representation of what appears to be a much larger spider. It does this on the web it has built, producing a much more intimidating decoy complete with head, abdomen and long, spidery legs, spread out from the main body. And when the rains that can fall at any time of year in the rainforest inevitably destroy their creation, these tiny spiders set to work once more, and build themselves another fake spider.
While it was quickly identified as a new species of the genus of orb-weaving spiders known as Cyclosa, Tambopata’s decoy spider was found to be behaving very differently from the majority of its arachnid cousins. For, while other orb-weaving spiders have been observed using forest debris and prey remains to build structures that appear to aid them by creating camouflage, the Tambopata decoy spider appeared to be doing something else.
Although the exact reason for this extraordinarily creative behavior remains the subject of debate, given the large size of the structures produced some scientists have speculated that Tambopata’s remarkable little decoy spider creates sculptural representations resembling a much larger arachnid as a way of deterring potential predators. Whatever the reason for this remarkably complex behavior, scientists now believe that there must be more species of decoy spider, not just throughout the forests of Tambopata, where we operate our sustainable, conservation-based ecotourism programs, but also in other forests around the world, all busily building larger, more fearsome versions of themselves to suspend from their webs!
Picture: Cyclosa conica, another small orb-weaving spider.