Vultures Are Messing With US Border Protection

A radio tower for the US Customs and Border Protection near the US-Mexico border has have been dealing with some unwelcome visitors.
According to Business Insider, the tower has been plagued by vultures.
They roost there and drop feces, vomit, and even prey on the buildings below.
Around 300 vultures have taken over the tower in the past six years.
They've coated the structure with "droppings mixed with urine," as well as corrosive vomit that eats away at the metal.