SAN FRANCISCO (AP) — An invasion of aggressive lice appears to be behind the balding of deer across California and may even be linked to deer deaths, according to state wildlife officials who are studying the hair loss.

Since 2009, researchers have collected hair and blood samples from more than 600 deer and elk with symptoms ranging from a scruffy-looking coat to almost complete baldness, the San Francisco Chronicle (http://bit.ly/12eXN8o) reported Monday.