South east Farallon Island, on Wednesday October 12, 2011, off the coast of San Francisco, Ca. Efforts to control the non-native house mice problem in the Farallon Islands have failed. Officials say the mouse population has grown so large that they have a

South east Farallon Island, on Wednesday October 12, 2011, off the coast of San Francisco, Ca. Efforts to control the non-native house mice problem in the Farallon Islands have failed. Officials say the mouse population has grown so large that they have aSouth east Farallon Island, on Wednesday October 12, 2011, off the coast of San Francisco, Ca. Efforts to control the non-native house mice problem in the Farallon Islands have failed. Officials say the mouse population has grown so large that they have altered the ecology of the island. (Photo By Michael Macor/The San Francisco Chronicle via Getty Images)