Australians celebrating Halloween this week are being warned that common decorations in gardens could cause serious damage. Cheap fake spider webs made from synthetic fibers are having a frightening effect on the country's wildlife.

According to experts at the University of Sydney, native birds, bats, lizards and possums are at risk. The experts have urged residents who want to celebrate the event to look for alternative decorations as those made from natural materials are less harmful.

The lecturer and researcher in biology, Dr. Catherine Price, issued a warning on Monday, saying animals could be trapped while gathering food or nesting material. “Research suggests that about 30 percent of bird nests may contain human-made materials, posing a risk to nestlings,” she said.

In recent years, Internet posts featuring images of animals caught in the nets have gone viral, but this year Yahoo News has gathered evidence that shows they are also a problem in Australia.

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Which Australian animals are caught in Halloween decorations?

The American custom of decorating front yards to celebrate the ancient pagan tradition has become increasingly popular in Australia over the past five years, and rescue group WIRES has since responded to several calls for help.

Earlier this year, it was reported that strands of spider webs had become entangled around the wings of a yellow-throated honeyeater in the western Sydney suburb of Dulwich Hill. Unfortunately, it disappeared before rescuers arrived, and whether it survived is unknown.

Last year a magpie's foot got caught in nets in the north of the city. While in the eastern suburbs, an unknown brown-and-white bird got caught in the trap and remained dangling for “a while.”

Professor Dieter Hochuli from the University of Sydney said fake webs function like real ones, but do not feed spiders and serve no real purpose.

“They seem like an unnecessary way to cause harm. There is a chance that you will trap a lot of unsuspecting and harmless animals in your polyester decorations, which can also end up being incorporated into nests,” he said.

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