NEBRASKAland Magazine is dedicated to outstanding photography and informative writing with an engaging mix of articles and photos highlighting Nebraska’s outdoor activities, parklands, wildlife, history and people.
Issue link: http://mag.outdoornebraska.gov/i/708333
16 NEBRASKAland • AUGUST-SEPTEMBER 2016 Testing with Drones Z ebra mussels are a non-native invasive species that have invaded much of North America. If present, they can take over aquatic areas quickly: a female zebra mussel can produce as many as one million eggs per year. Transportation of watercraft and supplies that have not been properly cleaned, drained and dried is often how this undesirable species is spread. The species alters communities of small phyto- and zooplankton (tiny plants and animals), and effects can cascade up food chains and alter lakes and rivers in fundamental ways. Waters may become more clear, but more prone to toxic algae outbreaks, and desirable fish species may be reduced. Additionally, they can clog power plant and industrial intakes. The economic impact of zebra mussels is estimated to be in the billions of dollars in the next 10 years. In Nebraska, zebra mussels have been found in Offutt Air Force Base Lake in Bellevue, Lewis and Clark Lake, the Missouri River below Gavins Point Dam, and just this year were rediscovered in Lake Zorinsky in Omaha. Biologists and managers are working to keep zebra mussels and other aquatic invasive species from spreading to other waters. Current sampling methods for the invisible aquatic larvae of mussels are time consuming, expensive and difficult. If the technology proves successful, unmanned aerial vehicles (UAV) – commonly known as drones – could be deployed at lakes around Nebraska to sample for zebra mussels more quickly and efficiently. At the University of Nebraska-Lincoln, biologists from the School of Natural Resources have been working with computer scientists and engineers of the NIMBUS Lab to develop UAV-based sampling techniques for zebra mussels. These techniques were tested at Offut Lake, and were successful in detecting zebra mussel larvae. The UAV was modified to include a pump and filtration system, allowing set amounts of water to be cycled through a very fine filter to capture the immature mussels. At the same time, variables such as water temperature and flow can be measured. The UAV can easily sample multiple locations at different depths, and includes GPS capabilities. They also do not require decontamination because the UAV itself does not come into contact with water. If successful, UAV technology will help facilitate the work of biologists such as Allison Zach, the coordinator of the Nebraska Invasive Species Council, and personnel of the new Aquatic Invasive Species Program at the Nebraska Game and Parks Commission. ■ Craig Allen is a professor for the Nebraska Cooperative Fish & Wildlife Research Unit at the School of Natural Resources, UNL. To test for zebra mussels, a drone has been fitted with a pump and filtration system that captures immature mussels. Jim Higgins of UNL's NIMBUS aerial robotics lab prepares a drone for flight to test for zebra mussels at Offut Lake. PHOTOS BY JENNY NGUYEN By Craig Allen