September 25, 2009 at 6:22 am (birds, botany, geology, insects (other), plant-eating insects, reptiles and amphibians)
Tags: aspen, beauty, Bombus impatiens, Bombus ternarius, bumblebee, false hemlock looper moth, Michigan, Muskallonge Lake State Park, Nepytia canosaria, pileated woodpecker, smooth green snake, Tahquamenon Falls, Upper Peninsula, Whitefish Point
by Carl Strang
In this final chapter of my Michigan vacation account, I will bring together assorted observations of other animals and sights. None of this truly counts as inquiry, except that travel and the exposure it gives us to new places leads us to make comparisons with our familiar environment. Such comparisons often lead to questions and inquiries on down the line.
At Muskallonge Lake, after completing my investigation at the beach, I went for a walk along the state park’s trails.
There were spectacular views of Lake Superior from elevated points, and flocks of migrating songbirds to investigate.
Tahquamenon Falls State Park is named for various waterfalls along the Tahquamenon River. Especially spectacular are the upper falls.
After a summer in which I made good progress in my knowledge of Illinois bumblebees, I was interested to find that in that part of the U.P., as back home, only one common species of short-tongued, generalist bumblebee is active at this point in the season. Here it’s Bombus impatiens; at the tip of the U.P. it was the beautifully marked Bombus ternarius.
B. ternarius is a northern species that does not extend its range down to Illinois.
One of the more charismatic birds that one hears and, sometimes, sees in the north woods is the pileated woodpecker. Here is a tree that has been well worked by that species.
Beauty on a smaller scale, which provided a reminder of the season in transition, took the form of this aspen leaf lying on a trail.
I spent most of my time at Whitefish Point. Here is a small scene I found especially compelling.
As I walked out from the point to the parking lot for the final time, I found an enchanting little animal crossing the trail.
Smooth green snakes occur in many places, but are so well camouflaged that we seldom have the good fortune to see them.
On my final morning at the Tahquamenon Falls campground, I found that a large number of moths had been drawn to the restroom building’s lights.
These were nearly all males of the same species, emerging all at once.
Nepytia canosaria, the false hemlock looper moth, is a common northern species whose larvae feed on a wide range of coniferous species including firs, hemlock, pines and spruces.
September 23, 2009 at 6:26 am (geology)
Tags: Agawa, bedrock, Canadian shield, continental glacier, glacier, granite, Green Bay lobe, greenstone, hematite, Illinois Beach State Park, Lake Maxinkuckee, Lake Michigan lobe, Muskallonge Lake State Park, Upper Peninsula, Whitefish Point
by Carl Strang
A second goal of my trip to Michigan’s Upper Peninsula last week was to investigate further the stones left by the most recent continental glacier. As I outlined in an earlier series of posts, my vacation trip last year was a pilgrimage into Canada to trace the route of the Lake Michigan lobe of that glacier, which is responsible for the deposits which cover the land in the northeast corner of Illinois. The turquoise line in the map below follows the route I think that lobe followed.
I studied the various categories of bedrock northeast of Lake Superior, chunks of which were picked up by the glacier and now reside where that powerful river of ice left them when it melted away. I found that there appeared to be commonalities in the stones left as drift along the Lake Michigan lobe’s route in Canada, on the Upper Peninsula of Michigan, and in northeast Illinois. Stones northwest of that route in Canada seemed different, and I was curious to see if those differences might hold farther south along the route of the Green Bay lobe, which is the one immediately west of the Lake Michigan lobe. I chose to visit Muskallonge Lake State Park, on the U.P.’s north shore, approximately in the center of the Green Bay lobe’s route, so that I could compare the beach stones there to those at Whitefish Point, at the U.P.’s tip, which was on the route of the Lake Michigan lobe.
It was a foggy day, but a few people were there. Some were gathering stones, a practice which might bias the results.
For instance, it seemed to me that beach stones at Canada’s Agawa Bay, along the Green Bay route, included an unusual number of red granites and greenstones. If these are selectively removed by visitors, the remaining stones might not represent what had been there originally. I certainly found greenstones, and in the following photo two appear.
However, there were very few compared to Agawa Bay. Here is a typical aggregation of Muskallonge stones, representing the Green Bay lobe.
Here is a corresponding photo for Whitefish Point, along the Lake Michigan lobe’s route.
While to my eye there did seem to be more reds and a few more greens at Muskallonge, and a few more grays and browns at Whitefish point, I don’t think the differences would hold up in a proper sampling procedure and statistical analysis. Furthermore, when I bring in a photo from Illinois Beach State Park (below), I am hard pressed to say that it is closer to one U.P. site or the other.
Nevertheless, the two years’ travel and study were enjoyable, and I learned a lot especially from studying the Canadian bedrock. The glacial drift may not provide additional support for the route map shown above, but the scratches on bedrock indicated by the little arrows in the geologists’ original map certainly are consistent with the turquoise line I added after last year’s trip.
Incidentally, there were places at Muskallonge Lake where there were deposits of black sands, I suspect composed of hematite like I found at Lake Maxinkuckee last winter.
The next installation from this trip will be more biological.