A Northwoods Almanac For 9/18 - 10/1, 2020 by John Bates
Goldfinch Chicks
Adult goldfinches were still feeding chicks as of 9/10, at least in Manitowish where we watched out our window as two chicks on a nearby branch begged a male goldfinch to give them sunflowers seeds from one of our hanging feeders.
Goldfinches are one of the latest breeders of all of our songbirds, normally waiting to nest until early July, but some procrastinate until mid-August. During the first Wisconsin breeding bird atlas, the latest Wisconsin nest observed with eggs was found on 8/25, although in Ontario, the latest date birders there have recorded is September 24.
The young fledge in about 12 days, but then they remain dependent on their parents to feed them for about three weeks. We watched as the adult male regurgitated sunflower seeds into the mouths of the very vocal chicks. For goldfinch chicks, all food is provided in the form of a sticky mass regurgitated by the parents, which while effective, is not as lovely as watching a cedar waxwing pass a serviceberry to its mate.
Why goldfinches choose to nest so late in the summer isn’t well understood, but some research has indicated that the downy seeds of thistles are an important nesting material. Since thistles don’t flower until mid-July, goldfinches are relegated to nesting after most songbirds have long ago fledged their young.
Most pairs have time to produce only one brood in a season, although experienced breeders frequently produce two broods if eggs are laid early and the first brood is successful. To permit such second nestings, the female abandons her first brood to her mate, and then leaves to find another mate.
Many northern populations migrate, with the occurrence and extent of migration varying by sex, age, and latitude. So, unless you have banded goldfinches at your feeders, there’s no way to know if “your” pair(s) have remained the winter, or whether some northern birds have come south and found your sunflower seeds to their liking.
Moose!
On 9/9, Sharon Cook spotted a bull moose crossing Hwy. 51 about two miles southeast of Manitowish. Young male moose are well-known for taking long walk-abouts in the fall, apparently out exploring the wide world and perhaps hoping to find a female partner. So, likely that was what this was about, but no matter - given their rarity in our area, they’re always amazing to see!
Our Wisconsin DNR doesn’t conduct any research or management of moose, but they do collect the reports they receive of moose from observers. Researchers writing in an article in the scientific journal “The American Midland Naturalist” (Feb. 2020) analyzed the reports and described the current status of moose in northern Wisconsin. The WDNR had collected data from January 1991 to December 2017 from reports of moose through multiple methods, including in-person reporting at WDNR offices, phone calls, e-mails, and online through a large mammal observation form. Each report was verified by WDNR staff, and the county and year of the observation was recorded in a database. Since 2012, likely double-counted moose observations were eliminated given that moose are easy to identify by their unique size and appearance.
The WDNR documented 762 total moose observations by citizens from 1991–2017, with a mean of 28.2 moose observations/year. There was a total of 36 observations of calves (singlet or twins), but the observations did not include the estimated age of the calves (i.e., young of the year or yearling). Calf observations occurred in 21 of the 27 years, with a maximum of three in 2002, 2009, and 2012.
Where are these moose coming from? Northern Wisconsin shares with northern Minnesota and the Upper Peninsula of Michigan the southern limit of moose distribution in the U.S., but our numbers are much lower than our state neighbors. The moose population in Minnesota was over 8,000, but has declined since 2006 by more than half to an estimated 3,150, and currently has a distribution limited to the far northeast. In contrast, 59 moose were re-introduced to the U.P. in the late 1980s, and surveys indicate the population has grown to approximately 400 individuals with a stable distribution.
The researchers suggest that the proximity to Michigan and Minnesota has had the greatest effect on the probability of moose occurrence in Wisconsin. Basically, moose wander down out of Minnesota and the U.P. and into our state, though they found evidence that the effect of proximity to Minnesota has diminished over time.
The factors likely regulating Wisconsin’s moose populations include forage availability, disease, and warming temperatures. Moose require large areas (about 36 square miles) composed of shrub, wetland, deciduous mix, and conifers for sustainable populations. However, even where habitat is sufficient, the effects of brain worm (meningeal worm Parelaphostrongylus tenuis) carried by white-tailed deer cause moose mortality. So, where we have better winter deer survival due in part to warming temperatures, and thus high deer abundance, the transmission rate of the disease typically increases. The natural southern limit of moose is believed to be climate-mediated, and heat stress on moose may have a cumulative effect on moose survival.
However, the researchers caution that despite ongoing research, it is currently unknown how these factors affect moose distribution in Wisconsin. They call for future research to consider the relationship between disease transmission and environments favorable to moose, deer, and gastropods (the intermediate host of the brain worm).
Other Sightings
Leaves on shoreland and wetland trees, like silver maples, have colored-up quickly because they are stressed by continuing high waters. However, most upland trees, at least as of this writing on 9/14, are relatively unchanged.
Our first hard frost in Manitowish occurred on 9/10, though many places around the Northwoods have yet to frost. Insects are, of course, extremely vulnerable to frost, but a few species are capable of surviving our winters. The following butterflies hibernate through the winter, finding shelter in wood piles, beneath loose bark, or in hollow trees or logs: Compton and Milbert's tortoiseshell (the tortoiseshell butterflies often hibernate in groups and may even congregate in sheds or outbuildings for shelter), eastern comma, gray comma, mourning cloak, and question mark.
Snapping turtles have been hatching out in the last week. Art Foulke sent a photo of one and noted, “Found on our walk this snapping turtle along with at least 15 others trying to cross the road to the creek. Two did make it and the rest either got ran over or simply died trying to get to the creek.”
Tim Kroeff in the Hazelhurst area sent this note: “Pretty good number of nighthawks the last few nights. Thursday, 9/10, they were much higher in altitude and seemed to be going through in flocks. The last two nights, some kind of hatch was going on and they were much lower, some dodging me at less than 10 feet while I was fishing. Could actually hear their wings when they were weaving to catch bugs. They must eat an incredible number!”
On 9/11, Mary, Callie, and I camped at Imp Lake near Watersmeet, MI, where we hiked the beautiful 1.5-mile-long Imp Lake trail through a mature hemlock-hardwood forest. We took well over two hours to cover the trail, going slow, poking around, and trying to identify various mushrooms and other flora. Highlights include finding bird’s nest fungi, a tiny fungi that is best identified by the appearance of a brown, gray, or white outer “nest”, with brown or white “eggs” inside. The “eggs” are actually spore-containing structures that rest inside the ¼ inch diameter cup-shaped fruiting body. When it rains, the “eggs” are splashed out of the “cups” and can travel four feet or more before sticking to another object. Then when the “egg” dries, it splits open releasing fungal spores. Amazing!
Ostrich ferns were full-grown along many areas of the trail, their unique dark brown fertile fronds rising from the center of the vase of leaves.
And we were required to poke some wolf’s milk slime mold, as well as delight in popping the seedpods of spotted touch-me-not (jewelweed) because no matter how old we get, we still can’t contain our inner junior high.
Seek (and you shall find)
I had heard of the iNaturalist app for several years, but I had never tried it until this week, and I was quite impressed! The Seek program within iNaturalist allows you to use your cell phone to photograph a species of plant, insect, bird, et al, and then ask it to identify the species. While it struggles to ID species that are often complicated to identify, like mushrooms and lichens for instance, it works very well on most flora, and even does well on insects which are often difficult to figure out. It’s free, too, so that’s hard to beat.
Download it at https://www.inaturalist.org/pages/seek_app
Hawks Migrating!
This from the Hawk Ridge website (www.hawkridge.org) in Duluth on 9/13/20: “What a day! Great passerine flight in the morning, over 6,000 blue jays, (35,000-/+ for the season). Lots of thrushes, warblers and straggling nighthawks, nuthatches and then the day died, winds were minimal and very overcast. The day we hoped for was not materializing.
“However, 1 p.m. rolled by and the skies cleared. Little did we know what was happening up north. The counters spotted a small kettle of broad-wings and then a dark Swainson’s hawk; perhaps the day was not done?
“Between 1 and 6 p.m., over 9,500 broad-winged hawks graced the ridge and gave the counters their first real test of the season.”
Hummers Gone
The last day we saw ruby-throated hummingbirds at our feeders was 9/8, and I expect by now nearly everyone in our area has seen the departure of “their” hummers.
The 3-inch-long ruby-throated hummingbird weighs 3 grams, about a tenth of an ounce, but will gain up to a whole gram of fat each day before migrating. Hummers migrate during the day, rising in the morning and fueling up on nearby flowers before spending the day migrating.
So help them out by keeping your feeders up for a few more weeks to sustain any late migrants coming from further north.
Temperature Stats
The National Oceanic and Atmospheric Administration reported that the 3-month season from June through August 2020 was the Northern Hemisphere’s hottest meteorological summer on record, surpassing both 2019 and 2016 which were previously tied for hottest.
The Northern Hemisphere also had its hottest August on record with a temperature departure from average of 2.14 degrees F, besting the previous record set in August 2016.
Thought for the Week
“We are showered every day with the gifts of the Earth, gifts we have neither earned nor paid for: air to breathe, nurturing rain, black soil, berries and honeybees, the tree that became this page, a bag of rice, and the exuberance of a field of goldenrod and asters at full bloom.” - Robin Wall Kimmerer
Please share your outdoor sightings and thoughts: e-mail me at manitowish@centurytel.net, call 715-476-2828, snail-mail at 4245N State Highway 47, Mercer, WI, or see my blog at www.manitowishriver.blogspot.com.
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