A unique breedBlue heron rookery on shore of Lake Ilo
A rare treasure for birdwatchers is located in a small grove of cottonwood trees on the north shore of Lake Ilo.
LAKE ILO NATIONAL WILDLIFE REFUGE — A rare treasure for birdwatchers is located in a small grove of cottonwood trees on the north shore of Lake Ilo.
A small rookery of great blue herons makes their home atop the trees. In all there are about 10 to 15 nests, with some trees holding three or four nests.
“It’s unique to have a rookery of blue herons,” said Kory Richardson, manager of Lake Ilo National Wildlife Refuge.
He said some blue heron rookeries can approach 500 nests.
“They typically nest in tall trees,” Richardson said.
The blue heron is migratory, with the birds making their way to Central or South American during winter.
The great blue heron is quite a sight, as it can grow to over 4 feet tall from bill to tail.
“They are definitely interesting birds,” Richardson said.
The rookery has been at Lake Ilo for several years, at least before Richardson moved to the area.
The lake itself has been around since the late 1930s, with the construction on the dam starting in 1936.
“The lake has been here for over 70 years,” Richardson said. “I’m sure the herons have been using it for a large portion of that.”
Richardson said they can be seen near the spillway of the dam looking for frogs, salamanders and fish.
“It’s unique to see them down on the ground on there like that,” Richardson said.
Though he’s not sure of where any other blue heron rookeries are, he said it’s possible that back bays along Lake Sakakawea could be home to some.
“I’ve worked on a lot of refuges, and this is the only one I think that had one,” Richardson said.
Despite the refuge being home to a rare blue heron rookery, many birdwatchers aren’t aware of it, Richardson said.
“Most birdwatchers don’t even realize the fact that there are blue herons here,” Richardson said.
The refuge itself doesn’t attract many visitors.
“We’re a fairly small, kind of out-of-the-way refuge,” Richardson said.
He said some visitors to Theodore Roosevelt National Park, mainly East Coast birdwatchers, swing by.
The rookery is located about a 1,000 feet east of the picnic area along a trail.
The refuge is located five miles east of Killdeer on state Highway 200 or one mile west of Dunn Center.
It’s open seven days a week from sunrise to sunset.