Dave Hallock, Eldora. As usual, the weather influenced the timing and abundance of various plants and animals seen this summer in the Nederland area. The three-foot snowfall of mid-May provided ample moisture for the first part of summer, but also made life difficult for many high elevation creatures.
The thirty-sixth year of the Indian Peaks Breeding Bird Count found that birds were more congregated in the montane lifezone (from 7,000 to 9,000 feet elevation in the count area) than usual. It is likely that the late snowpack in the subalpine lifezone (9,000 to 11,500 feet elevation) caused many birds to avoid the highest elevations and breed lower – this was most evident for Broad-tailed Hummingbirds. The late snowpack also impacted birds on the tundra. Horned Larks, one of the common breeding birds of the tundra, were almost absent and were not found in lower elevation grasslands of the count area. It is not clear if they simply did not breed this year or if they joined their cousins on the prairie, which is where most Horned Larks breed in Colorado.
Some wildflowers appeared more common than usual and may have benefitted from the mid-May dump of snow. Paintbrush, monument plant, aspen daisy, and hairy golden aster had spectacular blooms. The diminutive pink cushion-plant, moss campion, was quite showy on the tundra, but I had a hard time finding the little blue alpine forget-me-nots.
The abundance of monument plants (Frasera speciosa) in grasslands was of particular interest. Also known as green gentian, they send up flower stalks 2 to 5 feet tall. They have pale greenish flower clusters and whorls of broad leaves that are present all the way up the stalk. They should not be confused with common mullein, which also sends up tall stalks and is a noxious weed. Until recently, monument plant was thought to be a biennial, with basal leaf growth in the first year and flower stalk in the second year, followed by death. Dr. David Inouye has been studying the growth habits of monument plants since 1973 at the Rocky Mountain Biological Laboratory near Crested Butte. He has found that the plant lives in its basal leaf form for 20 to 80 years, then will produce a flower stalk, after which it dies. Plants that grow for many years, flower once, and then die are called monocarpic, with probably the best known being the century plant, an agave of the Southwest deserts. The flowering of monument plant appears to be synchronous, with many plants all blooming in the same year. This summer. Dr. Inouye feels there are environmental factors that trigger the flowering, such as the summer moisture in previous years. A good place to see the stalks of this year’s flowering Monument Plants is the Caribou Townsite area.
Painted Lady butterflies were present throughout the summer. Back in April, they made a major migration from the Southwest deserts, the largest migration we have seen since 2005. These butterflies are orange with black and white markings and are quite conspicuous when present. After the initial migration, a number of them stayed locally and produced at least one, and maybe two, additional flights.
After the mid-May snow dump it became dry with no measurable moisture until mid-July. Plants were starting to wilt and a number of the cool season grasses failed to produce much seed. Rains finally came in late July, into August. This is what the warm season plants were waiting for.
Mountain muhly, one of our dominant warm season grasses, sprang into full growth providing a new layer of green in meadows and woodlands..
Following are some of the September nature happenings in the Nederland area. I call this the time of “dropping cones and shedding needles.” Squirrels are dropping pine cones to the ground for winter reserves to be stashed in their middens. Needles on many conifers will start turning brown, particularly on lower branches and the inner portions of other branches, as the trees shed excess foliage. Of course, if you see all the needles turning brown, you may have a larger problem.
Berries continue to ripen. Look for huckleberries, chokecherries, raspberries, and others. If you hit a good patch of huckleberries, you can smell their wonderful aroma in the air. Black bear diets heavily shift toward berries as they gorge themselves for winter hibernation; this is evident in their scat.
Bull elk are bugling. The peak of the rut occurs around the end of September. Moose also start having other things on their mind, as breeding begins around mid-September and runs until early November.
Pocket gophers will continue to aerate the ground by tunneling and leaving mounds of dirt on the surface.
Birds are on the move. Flocks of sparrows, warblers and bluebirds are coming from the north, while local birds are flocking up and getting ready to head south. The tundra is a good place to see migrating birds that are feeding on abundant grasshopper and cricket populations. Raptors, including Red-tailed Hawks, Golden Eagles, Northern Harriers, American Kestrels, Peregrine Falcons, and Prairie Falcons frequent the tundra during fall migration.
A few butterflies will still be around in September. Some of these, like commas (orange with black spots and angular wings) and mourning cloaks (large, dark brown with yellow stripes), will overwinter as adults and can emerge during warm periods in winter or in early spring. While not much is known about painted ladies migrating south, some are often seen in September and October in high elevation meadows making a strong southwest movement.