A Northwoods Almanac for 6/6 – 6/19/25

 A Northwoods Almanac for 6/6 – 6/19/25 

 

Bird Counts

            Mary and I worked on two bird counts in late May – one in Iron County on 5/19 and another a week later on the Bear River on 5/26. The count in Iron County was our third annual and reflects an attempt to establish a baseline of what birds currently breed in the county so we know over time what populations are in decline, are stable, or even increasing. 

            We had counters in five general localities and came up with 114 species, a decline from the previous year of 137, but actually pretty good given the 40° temperatures and strong winds. Mary and I counted in the Mercer area working in a variety of different habitats including the Little Turtle Flowage, some wetlands along old Hwy. 51, the open fields of Mercer’s business park in Mercer, a woodland trail along Cty. J, and in and around our home area in Manitowish.

            Conspicuous by their absence were a number of ordinarily easy to find wetland and waterbirds like blue-winged teal, green-winged teal, ring-necked duck, herring gull, American bittern, and green heron. And we missed some ordinarily common woodland birds like winter wren, Eastern wood-pewee, and rufous-sided towee, 

Still, we did find a few that we didn’t have last year including American pipit, northern cardinal, warbling vireo, pied-billed grebe, and white-crowned sparrow.

The following week the temperatures and wind were far kinder – we began early in the morning at 42° but the temps spiked up to 68° by late morning, and the winds were negligible. We paddled up the Bear River a few miles from the put-in on Hwy. 182, and eventually drifted back down. After 5 hours, we tallied 61 species, the highlight for me being the numerous  occasions we heard northern waterthrushes singing. This is a warbler species that we seldom encounter, and we heard at least seven different individuals along the wetlands that bordered nearly all of the river.

Mary paddling on the Bear

Northern waterthrushes aren’t brightly colored, but they do sing an emphatic song that once you learn it is easy to ID. However, to see one is another matter. They are a furtive, skulking bird of shoreline thickets and shadowy understories, and we never saw a single one, no matter how close to us they seemed to be singing.  

            We love doing bird counts, though the getting up early has gotten a bit old. But once you’re out there, and it’s just you and the birds, that’s a slice of heaven.

 

Catbirds and Baltimore Orioles – A Love Affair with Oranges

            For the last two weeks, we have had both Baltimore orioles and gray catbirds sharing, albeit grudgingly, oranges that we’ve cut in halves and placed on a deck railing. The best moment was when we had a female oriole, a gray catbird (the genders look alike), and a male oriole. all in a line eating oranges.

Oranges must be quite a treat for the two species, but catbirds in particular are known for being fruit-lovers. While their diet includes a variety of insects – mainly ants, beetles, grasshoppers, caterpillars and moths – they consume fruits from dogwoods, cherries, blackberries, raspberries, elderberries, winterberries, et al. Averaging out numerous studies, the percent of fruit in their diet by volume varies throughout the year: Winter 76%, spring 20%, summer 60%, and fall 81%.

gray catbird, photo by Bev Engstrom

In one study in northeastern Pennsylvania, 75% of the fruits they ate during fall migration (collected from fecal samples) contained evidence of non-native fruits like honeysuckle, buckthorn, and autumn olive. While I’m glad a species like catbirds benefits from non-native fruits, the downside is that the catbirds then distribute the seeds far and wide through their whitewash.

Baltimore orioles eat an array of different food than catbirds, including caterpillars, fruits, adult insects, and spiders. They’re really good at picking insects from spiderwebs, and are an important predator of orchard tent caterpillars which they extract by tearing open the webs. In a Manitoba study, the nesting density of Baltimore orioles nearly doubled in the second year of a two-year outbreak of forest tent caterpillars.

Baltimore oriole female, photo by Bev Engstrom

In Colorado and New York studies, caterpillars formed over 30% of their total diet including other pests such as fall webworms, spiny elm caterpillars, tussock caterpillars, tent caterpillars, and the larvae of gypsy moths (now called spongy moths) and browntail moths. So, Baltimore orioles do their small part in reducing invasive insects.

But, they also can be a problem, picking peas from plants, fruit from trees and vines, and impacting tomato, citrus, and grape crops.

Nevertheless, they are gorgeous visitors at everyone’s feeders, and besides oranges, I’m told they also feed on bananas, which we’re going to have to try putting out for them.

They like the sugar water in hummingbird feeders or in sugar-water feeders specifically designed with larger holes for orioles. In natural settings, they feed on nectar, especially of trees, vines, and epiphytes in more southerly climes, and like other nectar feeders, they’re known to help pollinate various tropical plants.

 

Two Distinctive Voices – More on Catbirds and Orioles

Catbirds belong to the family Mimidae, and as their name (Latin for “mimic”) suggests, they’re notable for their remarkable ability to mimic a wide variety of birds and other sounds heard outdoors. Their vocal versatility stems in part from the structure of their syrinx, which has two sides. They’re able to produce sounds using both sides of the syrinx together, using the right or left side alone, or by switching from side to side. Both sides are able to operate independently, thus the gray catbird can sing with two voices at the same time.

The song bursts forth in a long series of short, syllables rapidly and randomly sung at an uneven tempo. Their repertoire includes syllables of more than 100 different types varying from whistles to harsh chatters, squeaks, and mimicry, resulting in what sounds like an improvised babble of notes with the familiar “mew” tossed in on occasion. To me, they’re jazz musicians improvising tunes only they can play and understand.

Their song is similar to our other mimics – brown thrashers and northern mockingbirds –  but catbirds usually don’t repeat phrases, whereas thrashers often repeat phrases twice and mockingbirds three times.

A catbird’s song may last up to 10 minutes with the phrases delivered at rate of about 90 per minute. One Michigan bird employed 170 different syllables during 4.5 minutes of song.

They do imitate the songs and calls of other birds found in the same or adjacent habitats, and are believed to mimic at least 44 species of birds, Eastern gray tree frogs, and a variety of mechanical sounds. But laboratory evidence indicates that the male’s song results mostly from improvisation and invention, not via imitation. 

            Baltimore orioles don’t mimic anybody. Instead, they sing a variable, rich, and strong song that consists of relatively few notes or groups of notes. It is “loud, clear and of flutelike quality,” says one account. Another account refers to the notes as “pure tones.”

They also give a loud chatter call consisting of many repetitions of the same note – up to 38 for males.

Male Baltimore orioles like to continuously switch among song types, only rarely repeating the same song even two or three times in succession. They apparently get bored with singing the same old tunes! 

 

The Huron Mountain  Club

            In mid-May, I was finally able to visit the Huron Mountain Club, a private enclave of 16,000+ acres on Lake Superior in the U.P. of Michigan. The Club has retained around 8,000 acres of remnant old-growth hemlock-hardwood forest, making it the third most important site in the entire upper Midwest for old-growth forest. So, naturally I’ve been juiced to go there for decades, but entry is only permitted by invitation from one of the Club members or by being a part of a research team.

            I was lucky to be able to tag along with a couple researchers looking at the impacts of deer browse on hemlock reproduction, and then doubly lucky to have a little time to myself to explore one small area that represented the best remnant white pines on the property. One of the researchers took us right to a 53” diameter breast height (dbh) white pine, the largest diameter he knew of on the property, and the largest I have ever seen in my many years of looking for old-growth in natural woodlands. Later, I found along a creek a 56” dbh white pine with what appeared to be a large and very old fire scar. 

53" dbh white pine in the Huron Mts.

            Wow!

            Michigan and Wisconsin settlers and loggers did an extraordinary job of cutting 99.9% of our old-growth pines, so they’re a rare commodity these days. Seeing these big grandmother trees was quite the blessing.

 

Sightings – Loon Attack, White Pelican, Cedar Waxwings, and Red-headed Woodpeckers

            John Randolph in Hazelhurst  sent me this note on 5/23: “My daughter Kat and I witnessed several close-by attacks by a Loon on a sizeable group of Common Merganser ducklings, being defended by the Merganser female. It appeared that some of the ducklings did not survive. The Loon seemed to attack from under water. Also, at the same time, there was a pair of loons nearby, not involved in the attacks. Our lake is small, and loons have tended to nest on a larger, connected lake.”

            Territorial loons are well-known for attacking other waterfowl on “their” lake, as well as having unmated loons attack them in an attempt to usurp their territory. Life in the world of loons isn’t all lovely wail calls echoing across a calm lake.

            Mary’s and my most remarkable sighting of the month was on May 27 when we watched a white pelican lounging on Whitney Lake near Boulder Junction. White pelicans currently are known to nest in at least seven different locations in Wisconsin, none of which are remotely near Boulder Junction. However, since the birds don't mate and nest until five or six years of age, non-breeding pelicans are being seen in other parts of the state, too, so perhaps this was a younger one out on a foray checking out possible future nesting areas, or just out on a lark.

            Cedar waxwings returned to our yard on May 25, which usually signals to me the end of bird migration and the end of what passes for us as “spring.” The waxwings immediately began eating the petals from our numerous apple and crabapple trees, a practice I have come to believe doesn’t harm the flowers and thus ultimately the fruit.

cedar waxwing eating crabapple petals, photo by Bev Engstrom

            Finally, red-headed woodpeckers made a splashy appearance around the Northwoods for a few days in mid-May. 

            Paul Strong in Hazelhurst emailed me on 5/16 saying they had a red-headed woodpecker at their suet feeder. He noted, “There have been a number of forest management activities in the four square miles around our house. Many of them are significant thinnings, which may be attracting more RHW's for a while.” 

red-headed woodpecker, photo by Bob Kovar

            Paul, the former forest supervisor for the Chequamegon-Nicolet National Forest, knows his habitats. Red-headed Woodpeckers are most often found in a variety of forested habitats with a certain degree of openness and presence of dead limbs or snags for nesting purposes. They’re a cavity nester, so they have to compete for nesting sites, which can be a problem in areas where nest sites are scarce and/or where aggressive interactions with the non-native European starling take place.

            They remain quite uncommon in the Northwoods – they’re a species of special concern throughout the state – so any sighting of them is a good day.

            We had one show up at our feeders on 5/18, but it only stayed a day. Bob Kovar in Manitowish Waters had one also appear on 5/18, and he sent me some fine photographs of it.  

 

Thought for the Week

            “I hope you love birds, too. It is economical. It saves going to Heaven.” – Emily Dickinson