Drush fef has error when called with no parameters

vagrant@dev1:/etc/drush$ drush fef
Please enter the site name you would like to work with or n to cancel: n
This site information could not be loaded.                                                                                                                                                                                       [error]
Please enter the site name you would like to work with or n to cancel: n
strtr(): The second argument is not an array output.inc:146                                                                                                                                                                      [warning]
Site information could not be found