This article is full of goodness:

Moeliker said that in essence, the lice's habitat is being threatened.

"When the bamboo forests that the Giant Panda lives in were cut down, the bear became threatened with extinction. Pubic lice can't live without pubic hair."

...and this one:

"We learned this lesson with the house sparrow. Twenty years ago we thought, 'why bother to get one?' since they're so common," he said.

"Next thing you know, the sparrow was on the threatened species list and they're almost impossible to find in the Netherlands."