"Biomonitoring is a brilliant concept. <br>That can be used in a lot of contexts.<br><br>The proverbial canary in a coalmine has already been named further down", other water providers use water fleas (Daphnia magna) for the same process.<br>I´ve recently come across german woodland managers using the observation of certain bird species to ascertain bark-beetle infestation levels. And read about a NY based project catching and dissecting rats to gain insights on pollutant levels in sewerage. Observers of the Chernobyl exclusion zone collect the fruiting bodies of certain mushroom species who tend to agglomerate radioactive elements.<br><br>Observing living networks can gain us a lot of information otherwise hard to come by.