OMAHA, Neb. – The Missouri River Recovery Program’s Emergent Sandbar Habitat Program and Tern and Plover Monitoring Program, managed by the U.S. Army Corps of Engineers, Omaha District’s Threatened and Endangered Species Section, continues to improve habitat and reproductive outcomes for the threatened Northern Great Plains piping plover and formerly endangered interior least tern.
The piping plover and interior least tern are small shorebirds that nest along the Upper Missouri River. The two species were once widespread throughout the Northern Plains, but their numbers declined considerably during the 19th and 20th centuries when their natural habitat was altered by recreation, hunting, shoreline development and construction of six upper Missouri River dams.
The birds have very limited nesting areas and prefer coarse sand or gravel beaches on sandbars not connected to adjacent riverbanks. Clearing vegetation from sandbars is one tool used in the program to create and maintain suitable nesting habitat.
“The birds like to nest in large areas of bare sand out in the middle of the river,” said Galen Jons, Omaha District natural resources specialist. “As vegetation grows up in those areas, it creates hiding spots for predators. Those predators can destroy nests and even go after adult birds and their chicks. By controlling a lot of the vegetation around those peripheral areas, it really improves the bird’s success.”
Much of the vegetation control is done by helicopter, which is the most cost-efficient way to reach the sandbars. EPA-approved herbicides are applied to keep vegetation low and eliminate hiding spots for predators. However, Jons said threats to the species can come in other ways.
“One thing a lot of people don’t understand is that they can also be a predator without even knowing it,” he said. “People can get on the sandbars and that can disturb the birds. The birds can abandon their nests and that would kill the nests.
“These birds and nests look just like the sand. They’re very difficult to see, and people may not even know they’re there. We also have a lot of turtles out there in trouble, so we want to protect those turtle nests as well.”
Seasonal hires and natural resources specialists locate nests throughout the summer using binoculars and spotting scopes. Warning signs are posted to alert visitors of the nests, and their GPS coordinates are recorded so they can continue to monitor and research environmental impacts and hatching success.
Fluctuations in river and reservoir water levels can also pose a risk. Lake Sakakawea, located in North Dakota, is one of the first reservoirs to collect water from the upper Missouri River, including major tributaries such as the undammed Yellowstone River. Two specialists there are trained to handle and relocate the nests, broods and adult plovers.
“As our water level rises slowly, it puts those nests and broods at risk of drowning and going under on small low-lying islands,” said Scott Sterling, a USACE Omaha District natural resources specialist who is trained to relocate the nests and broods. “One of the tools we have in our tool belt is to physically move the chicks and the adults together to higher ground to make sure they are successful in their brooding.”
Recent reports show populations of the two species have increased considerably since they were first listed as endangered in the early 1980s.
“We have seen improvements,” said Galen Jons, USACE Omaha District natural resources specialist. “It varies quite a bit from year to year, but the more sand that’s out there, the more habitat that’s there for the birds.”
The interior least tern was removed from the federal endangered species list in 2021 and is now estimated at more than 18,000. The Northern Great Plains piping plover remains a threatened species, with an estimated population of 3,500 to 5,000.
The U.S. Fish and Wildlife Service initiated the first habitat and monitoring program under the Endangered Species Act in 1986, followed by USACE in 1993. USACE collaborates closely with USFWS, state conservation agencies, local partners and volunteers to maximize conservation efforts.
For more information about the Tern and Plover Program and other conservation efforts, visit https://www.nwo.usace.army.mil/mrrp/efforts-actions/esh/.