Most of the 10,000 ships lost to the bottom of the Great Lakes in wrecks over the past 400 years are still lost – hidden somewhere in 6 quadrillion gallons of water. Finding anything in a lake is a lesson in humility, so life as a freshwater biologist is always humbling. If we can’t account for huge steel freighters, imagine the challenge of finding a single tiny organism.
But it is crucial to detect invasive species as early as possible. Aquatic invasive species cause billions of dollars in economic damages, and regulators base multimillion-dollar management decisions on scientists’ and managers’ ability to detect them. It is much more cost-effective to invest in prevention measures than to react after a species becomes established. And low-density populations are easier to manage than species that have taken over an ecosystem.
But since funding, gear and time are limited, scientists often can only sample for invasives over small fractions of vulnerable areas. Compounding the challenge, our target species tend to lurk at low densities – that is, they are rare in most places.