How dogs sniff out invasive species of mussel in Montana

These canines were trained to detect zebra and quagga mussels, invasive species which have caused ecological problems in the US since first detected in the 1980s. Like their bomb-sniffing and drug-sniffing counterparts, these dogs have been trained to pick out the scent of zebra and quagga mussels in an attempt to identify the creatures before they take hold in a new area. These environmental watchdogs are typically deployed to boat-inspection sites to make sure any ships entering their domain are not carrying these unwanted stowaways.