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an organism or species whose declining health or numbers signal a larger environmental catastrophe to come
Abused, Confused, & Misused Words by Mary Embree Copyright © 2007, 2013 by Mary Embree
(Environmental Science) a human being or other living organism whose lack of health indicates environmental problems, reminiscent of the way in which live canaries were once used to detect the presence of poisonous gas in coal mines
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014