This holiday season, festive decorations may be at risk of being ripped down by an surprising culprit.

Colorado Parks and Wildlife (CPW) has warned residents of the state that they are receiving large numbers of calls from people who have had deer getting their antlers tangled up in their Christmas decorations and other yard equipment.

While deer are usually rather clumsy creatures, they become much more erratic and aggression-prone at this time of year, as they are frantically searching for a mate.

“Our wildlife officers respond to calls every year of deer stuck in various netting and holiday decorations,” CPW Area Wildlife Manager Adrian Archuleta said in a statement.

Colorado Parks and Wildlife warns residents that male deer may find themselves getting tangled up in swing sets, sports netting, hosepipes, Christmas lights and even bicycles during the rut season.

There are two main types of deer native to Colorado: mule deer and white-tailed deer. The rut of both species typically peaks in mid to late November and can extend into late December in some areas.

During the rut, bucks are highly active and display behaviors aimed at attracting does and establishing dominance over other males. This can include traveling extensively, often during daylight, and also engaging in sparring or even full-blown fights to establish dominance and breeding rights.

This activity is how the male deer end up getting tangled up in things like Christmas lights.

“In some cases, these hazards prevent the deer from being able to eat and breathe. Additionally, this causes high levels of stress on the animal and can lead to fatality,” Archuleta said.

The public is advised to ensure holiday decorations and lights are firmly attached to solid structures, and hung at least eight feet from the ground. Hanging the lights on trees or bushes is discouraged, as the deer often rub their antlers against plants or tree trunks to sharpen them during the rut.

If you encounter a deer that has become tangled or trapped, you should not attempt to free it yourself, as the deer are often increasingly aggressive at this time of year.

“When deer do become entangled, it is important for the public to call their closest CPW office quickly with location information,” Archuleta said.

“People should never try to free deer of these hazards themselves because of the serious risk of injury that can be caused by antlers and hooves.”

Additionally, deer can carry diseases such as chronic wasting disease, tuberculosis and acidosis. This is why it is illegal to feed wild deer in Colorado.

“Attracting deer can concentrate them in small spaces, making disease easier to spread, attracting predators, and causing them to lose their natural fear of people,” the CPW warn on their website.

During the rut, deer may be seen on the roads more frequently, so drivers are also advised to keep an eye out.

“Drivers are also reminded to slow down and be on the lookout for deer on highways. Not only are bucks in pursuit of a mate, but animals are also migrating to winter range and will be more present crossing roadways both on highways and arterial roadways,” the CPW said in the statement.

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