A local television station reports that the raccoons have temporarily brought the giant machine to a halt.
A crane operator spotted the new residents while ascending the tower Wednesday. The general contractor, Rafn Company, called in experts who are trying to catch the critters with humane traps.
Project superintendent John Kellberg says this is a first for him.
The apartment complex in the city's Ballard neighborhood is due to open in the summer of 2014. Sources reports that neighbors say large raccoons are common in Ballard.
