Cucujus clavipes is known as the flat bark beetle. Multistriatin is a pheromone of the elm bark beetle. It is one of the major aggregation pheromones of the bark beetle. Resins could have developed as an evolutionary defense against bark beetle attacks. Cryptolestes pusillus is a species of lined flat bark beetle native to Europe. It attracts the western cedar borer and cedar bark beetle. Cryptolestes ferrugineus is a species of lined flat bark beetle native to Europe. Other elm bark beetle species are also likely vectors. Since 2006, there has been increased bark beetle gradation. Because of warmer weather, another threat are mountain pine bark beetle infestations. Colorado's forests are densely wooded, making them much more susceptible to bark beetle attack. In the later outbreaks the die-back was attributed to the elm bark beetle. A 2013 bark beetle outbreak destroyed a quarter of all forests in Honduras. In Uganda, two lepidopteran species, two termite species, and one bark beetle attack "S. campanulata". The bark beetle is on the rise here due to climate change and global warming.