Scientists studying aquatic species have set the bar pretty high with their latest project: to create the first-ever aquatic map of the western United States. This means every animal in all the rivers, lakes, streams, brooks and creeks west of the Mississippi by the end of next summer. It’s certainly a lot of
ground water to cover in such a short period.
For Dan Isaak, project leader and biologist with the U.S. Forest Service, it is one of the most important research ventures being tackled today. “It’s kind of the Holy Grail for biologists to know what a true biodiversity map looks like,” he reports. “To have that formatted digitally so you can do lots of science with it will be transformative in terms of the quality of information we’ll have to conserve species.”
The map will include everything from aquatic birds and mammals to fish and insects. Many of these animals endure ongoing threats from residential expansion, but Isaak believes the map can educate developers into making better decisions. The map could also accrue funds for future conservation.
“Any time science undertakes large projects like this, the payouts can be in directions you don’t expect,” says Montana forest director Michael Schwartz, who agrees it’s important to catalogue the species in question, though he differs with Isaak regarding how much time will be necessary. Schwartz is skeptical efforts to build a legitimate map can conclude by summer, and says a full year is likely to pass before marks are made. Present technology only allows researchers to identify species one at a time, and the amount of information Isaak is bound to uncover could lead to more questions than answers.
John Kelly, a professor of biology at the University of New Haven, says aquatic species can be particularly difficult to locate. In a recent interview, he states, “One of the problems [with conservation] is that you have to look physically. It’s time intensive, and you always run the risk of simply missing something. Any tool that uses environmental DNA is intriguing because it’s going to integrate along large areas, potentially the whole watershed.”
Environmental DNA (or eDNA) fills in many blanks left over by traditional research tactics. Since 2009, eDNA has worked predominantly as a surveillance mechanism, finding DNA in water samples and local sources.
“With a tool like this, you can get a better sense of population distribution and target your efforts,” Kelly assures, though eDNA does not come without its limitations. A big one is its inability to identify native species. Fish such as Asian carp have been discovered in waterways unknown to naturally house carp populations. Those found likely swam in from neighboring waters, but eDNA cannot clarify if an animal is native or intrusive, nor can it accurately insinuate a populace’s size.
“We are reluctant to stretch any claims for eDNA until we know more,” says Les Kaufman of Boston University.
Still, Kelly claims it’s a positive step towards scientific advancement, and while it may not reveal all the answers men like Isaak are looking for, it’s bound to make things a little easier in the long run.
“You still have to go out and see what’s there,” he mentions. “It’s not going to replace what we’re already doing, but it’s another tool, and it sounds like a good one.”
Isaak is also developing the Cold Water Climate Shield project, to identify refuge water sources for cold water species threatened by climate change. Information from stream temperatures, topography and weather patterns will be used to pinpoint any safe havens. Like Kelly, Isaak also revels in the intimate power of eDNA.
“Data sets can be bigger because computers are bigger,” he explains. “It’s just been an ongoing revelation. It still seems like magic to me that you can go take a water sample and you have instruments powerful enough to discern what species are present.”