It’s been 25 days since the last post, during which time we have visited 21 locations in the Dakotas and the western edges of Iowa and Minnesota. Of these, 12 were preserves established by The Nature Conservancy (TNC), 7 were federal properties, and two were state parks.
Four tallgrass prairie sites were in the distinctive Loess Hills formation of extreme western Iowa. This narrow strip parallels the Missouri River and resulted from prevailing westerly winds piling up soil exposed by the retreating glaciers. The resulting “soil dunes” are the tallest in the world outside of China. The soil is quite rich and the rolling country very scenic. Locations we visited in the Loess Hills were two TNC preserves (Knapp Prairie and Broken Kettle Grassland) and two state parks (Five Ridges Prairie and Stone Ridge). Butterflies were especially notable in this region, including the magnificent Regal Fritillary at Knapp Prairie. One morning at Stone Ridge there were many hundreds of recently emerged Hackberry Emperors, which would alight on you if you stood still! Stone Ridge also had lovely forests with numbers of Yellow-billed Cuckoos and large examples of Kentucky Coffeetree and Black Walnut. The latter tree is so valuable for making fine furniture that there are stories of trees being stolen by helicopter.
The other 10 tallgrass prairie locations were Big Stone National Wildlife Refuge (NWR), MN and 9 TNC preserves (Vermillion Prairie, SD; Makoce Washte, SD; Sioux Prairie, SD; Altamont Prairie, SD; Jacobsen Fen, SD; Chippewa Prairie, MN; Hole-in-the-Mountain, MN; Mori Prairie, IA; and Freda Haffner Kettlehole, IA). Big Stone NWR has beautiful granite outcrops, which support 9 plant species not found elsewhere in Minnesota. We spent several days there unsuccessfully looking for one of our nemeses, Franklin’s Ground Squirrel, a secretive mammal occurring in tallgrass and mixed-grass prairie from Nebraska (where we saw one dead on the road) and northward. We also spent an afternoon there canoeing on the Minnesota River, where a brood of Hooded Mergansers was a highlight. The Freda Haffner Kettlehole was a neat geological feature; the small lake, ringed by rolling hills, was formed by an enormous chunk of ice that broke off a retreating glacier, and then melted in place, compressing the ground and filling the depression with water. Some of the interesting grassland birds we encountered repeatedly in these tallgrass sites were Dickcissel, Bobolink, Sedge Wren, and Clay-colored Sparrow. We heard a probable Franklin’s Ground Squirrel at lovely Jacobson Fen, but an hour of waiting produced no sighting.
The 7 mixed-grass sites we visited were TNC’s Samuel H. Ordway Preserve, SD; Cedar River National Grassland (NG), SD; Grand River NG, SD; Little Missouri NG, ND; Theodore Roosevelt National Park (NP), ND; Sand Lake NWR, SD; and Lostwood NWR, ND. Grand River NG had a very nice 7-mile hiking loop, the Blacktail Trail, which we walked early in the morning because of the heat (this was Day 2 of 8 days of intense heat, with highs to 105°F, and some nights that did not drop below 75°F). We took an unplanned day off at the Burning Coal Vein Campground in Little Missouri NG, because it was such an idyllic spot, and there was nobody else there, despite it being Fourth of July weekend. A Yellow-breasted Chat in our site sang almost continuously during daylight hours, and occasionally at night. Eileen found a Prairie Rattlesnake sunning in the road, which was new for me (Eileen had seen one in New Mexico when she toured the Santa Fe Trail). This sighting inspired me to spend our day off updating taxonomy of reptiles and amphibians in our database.
We arrived at the South Unit of Theodore Roosevelt NP on July 4. Most fireworks in North Dakota were cancelled this year because of fire hazard, so residents were traveling some distance to nearby Medora to see the show. We decided that an overlook inside the park would be a good elevated vantage point, and would avoid the massive traffic jam afterwards, and it worked out just that way!
The next day we visited two petrified forest areas in the South Unit, a 5-mile round trip hike. We got a very early start but it was already 100°F when we got back to the camper late in the morning. We both felt the more northerly area was the better of the two, especially at the very end, where a small valley contained about ten petrified tree trunks still standing vertically, a marvelous sight. At least some of those trunks were from American Baldcypress, the defining species of southeastern cypress swamps.
The two waterfowl refuges mentioned, Sand Lake NWR, SD and Lostwood NWR, ND, lie within the Prairie Potholes region. This area extends from southern Minnesota and eastern South Dakota, through North Dakota, and to the southern Prairie Provinces (Manitoba, Saskatchewan, and Alberta). It is characterized by rolling topography in which many of the depressions are filled with water, creating ideal habitat for breeding waterbirds, especially ducks. In 1987 we visited Lostwood NWR to see Baird’s Sparrow and Sprague’s Pipit, which have very limited breeding ranges. Unlike 30 years ago, this time we did not find the sparrow or pipit on the auto tour route at dawn, so we headed for a remoter area on the west side of the refuge, where they had been detected earlier in the season. As we headed down a gravel road to that area, I saw a ground squirrel duck into grasses along the side of the road. For what seemed like the 400th time in the last month, we stopped to check out what would no doubt be a Thirteen-lined or a Richardson’s Ground Squirrel, both abundant species … half a minute later it reappeared and we were in shock to see the diagnostic gray head and thick tail of a live, visible, Franklin’s Ground Squirrel!!
Afterwards, we did find both Baird’s Sparrow, with its endearing song, and Sprague’s Pipit, which sings from high in the air. We once calculated the height of one by measuring its image on a Kodachrome slide, and knowing the telephoto focal length and size of the bird — and it proved to be 700 feet above the ground!