At about 8 p.m. CST on Feb. 22, a portion of the Internet’s social universe watched as the world (on television) learned what many already believed, invaders are among us. But of course, that was the "X-Files".
In the real world, invaders ARE among us and this week, Feb. 21-27, has been National Invasive Species Awareness week. The invasive species aren’t from another planet though.
Across the United States, various invasive species threaten our natural ecosystems. The U.S. Army Corps of Engineers manages 12 million acres of public land and is the largest provider of water-based outdoor recreation in the nation with 403 lakes and river projects in 43 states totaling 55,390 miles of shoreline.
“That’s a lot of land and water to look out for,” said Jonas Grundman, an Omaha District Natural Resource Specialist. The Omaha District manages 6,627 miles of shoreline including reservoirs and rivers and 284 recreation areas.
“Some of the invasive species that pose a threat to our projects include Zebra Mussels, Rusty Crayfish, the Emerald Ash Borer, Asian Carp, and a variety of plants that can overtake natural ecosystems,” said Patricia Gilbert, a Fort Peck Project Natural Resource Specialist.
“In many cases, once the species – be it plant or animal – invades, all we can do is monitor, fight and manage them,” said Grundman. “We have to focus our efforts and rely on the public to help prevent the spread of invasive species.”
“Helping to preventing the spread of invasives really just requires a little extra effort and attention but can make a tremendous difference,” said Shelley McPherron, an Omaha District Biologist.
If visitors to public lands and waterways focus on three efforts, the spread of invasive species can be significantly minimized.
The first effort is, “Buy local. Burn local.” It’s a simple step to prevent losing hundreds of trees to a variety of invasive pests.
“Never transport firewood from one location to another. The Emerald Ash Borer as well as other naughty hitchhikers can easily stow away on firewood and that’s all it takes to lose a bunch of trees around a campground,” said Gilbert. Once the pests invade, they can easily spread from a recreation area to farmland and impact America’s crops.
The second is “Clean, Drain, Dry” A few extra minutes after a day on the lake, will prevent transporting invasive species between water sources. These “alien” invaders include zebra mussels, the rusty-crayfish, Asian Carp and others.
“We’ve seen some of these invaders in the Omaha District in the past five years,” says Grundman.
The impacts of these species have included an effort to eradicate zebra mussels at Lake Zorinsky in Omaha, Nebraska. In 2010, the Omaha District lowered the lake to take advantage of freezing temperatures prevent zebra mussels from reproducing.
Another effort to address invasive species included a fish renovation project at Lake Yankton at Gavins Point Dam. Undesirable fish species such as buffalo, shad, gar, drum and the invasive Asian carp, entered into Lake Yankton during high water levels in 2011. The species quickly drove out sports fish, were destroying aquatic vegetation, and began diminishing water quality.
In 2014, in partnership with the Nebraska Game and Parks Commission, water levels at Lake Yankton were lowered and chemicals were applied to eradicate the undesirable fish. Once they were eradicated, USACE allowed the lake to refill and the Nebraska Game and Parks Commission restocked the lake with sports fish.
The final thing we can do is “Identify”. Recognizing and reporting invasive species helps to prevent their spread. HungryPests.com from the U.S. Department of Agriculture is a great website for identifying and reporting invasive species.
Reporting suspected invasive species is important. “You can’t wait for someone else to do it,” said Grundman. The zebra mussels at Lake Zorinsky in Omaha were discovered and reported by a 13-year-old Boy Scout who was collecting cans for a scouting project. “He promptly reported his discovery, which was the first discovery of a zebra mussel in a publicly accessible Nebraska lake. And, what’s more remarkable is they’re gone from Lake Zorinsky.”