A Northwoods Almanac for May 14 – 27, 2010
Sightings
On 4/18, Jane Flanigan in Hazelhurst thought she had sighted an eastern bluebird, so she promptly put up a bluebird box. No bluebirds showed up, however, and five days later black-capped chickadees moved in! But on 5/1, the bluebirds arrived, evicted the chickadees, and are now nesting.
On 5/1, barren strawberry came into flower in the Manitowish Waters area.
On 5/2, Dan Carney in Hazelhurst spotted first-of the-year palm and Nashville warblers along the Bearskin Trail.
On 5/2, Pat Schwai on Cochran Lake reported the first black-throated green warbler of the year in our area.
On 5/3, we found gaywings in flower near Mercer.
On 5/5, we had our first rose-breasted grosbeak appear at our feeders.
On 5/6, Linda Johnson on the Tomahawk River reported the following: “While sitting in the den my husband heard an enormous bird strike against the window. In fact, he thought the window was shattering. Upon looking outside he saw a small hawk (sharp-shinned?) on the deck in a very contorted position. He went out and carefully righted the bird and then noticed a grackle lying on its back with its beak and eyes wide open about 20 feet away. He also righted this creature. Kevin had time to come in the house, dig out his camera and snap a couple shots. Then he let the two of them have some quiet time to either make it or not. About 20 minutes later he checked back and both birds were gone.”
Linda also noted that she watched a pair of northern flickers, the male of which was doing a display for the other by fanning his tail and hopping toward her. Apparently the female wasn’t impressed and flew away.
On 5/7, Mary and I observed gosling chicks on the Manitowish River. We also had our first northern oriole in our yard.
On 5/9, Sharon Lintereur in Lake Tomahawk reported the first indigo bunting of the year. She noted, “They are right on schedule according to my records.”
On 5/10, Diane Gaynor reported the first scarlet tanager of the year on her deck in Arbor Vitae.
Vultures Nesting?
On 4/30, Gloria reported the following from a site north of Rhinelander: “I was walking with my friend Jody . . . we scared up some vultures that were in an old fallen down building along the road. Not one or two, but at least 7 vultures came out of the building. We looked in the window expecting to see a dead elephant for that number of birds and could see nothing. Is this normal for this number and type of bird to roost in a building, or should we assume that they were feasting on something we did not see?”
On 5/9, Gloria followed up her earlier post with this note: “Went and checked out the site today and scared up five vultures from the building, so they must be roosting or nesting in there. Two of the birds were pretty reluctant to fly far from the site.”
The question I had for Gloria was whether she thought a pair might be nesting in the building (though the fact that there were 5 to 7 birds in the building would seem to suggest a roosting site rather than a nesting site). The reason I asked her about possible nesting is that data from The Atlas of the Breeding Birds of Wisconsin confirmed 33 actual nest sites statewide, half of which were in rock outcroppings. But about a third of the nests were found in artificial structures, of which most were in abandoned houses and farm buildings (three were found in elevated deer-hunting blinds!).
Atlas field observers were unable at that time (through the year 2000) to confirm any vulture nests in Oneida Country, but eight sites were listed as possible. Since turkey vultures tend to be secretive at their nest sites, the lack of confirmed nest sites may not demonstrate that no vultures were nesting here, but may simply indicate how good the vultures are at hiding their nests.
Turkey vultures were considered rare in Wisconsin until the mid-1900s – the first confirmed vulture nest in the entire state wasn’t found until 1947. But their population has been steadily on the rise since then, with mean annual population increases calculated at 15% for Wisconsin.
If Gloria’s site proves to be a nesting site, the female likely laid her average of two eggs in late April or early May. Incubation is by both adults, and lasts 28 to 40 days, with chicks usually appearing around June 1.
Turkey vultures are highly social, however, and roost communally throughout the year, so they may just be hanging out in the evenings in the abandoned house or loafing there during the days. Vultures typically roost in dead trees, on cell towers, and often on roofs. Though I’ve not heard of them roosting or loafing inside abandoned houses, I wouldn’t be in the least surprised – I’d think they’d like a roof over their heads.
Jazz Singers
On 5/4, Mary and I were awakened at dawn by a bird singing a wildly creative song below our open window. It took us both a moment to clear our heads, and then we looked at one another and said simultaneously, “Brown thrasher!” The thrasher was continuously riffing notes like a jazz musician at a late night club in Chicago. The songs came fast and furious in no discernible order or melody, the only distinguishing pattern being the repetition of each note in couplets – hi there, hi there . . . how are you, how are you . . . good day, good day . . . listen up, listen up – each couplet occurring about a second apart. We never heard any individual couplet repeated later in the overall sequence, though the thrasher voices so many songs that we’d have to record them and play them back in a lab to discover any duplicates. The thrasher sang his heart out for about 10 minutes, then departed, and we haven’t heard another since.
I hope one returns soon. The brown thrasher holds the world record among birds for most songs sung by a species, with a repertoire of somewhere between 2400 and 3000 distinct songs – researchers can only estimate the number. No other bird on Earth is so skilled and so versatile a songster.
Donald Kroodsma, author of The Singing Life of Birds, recorded in mid-May a brown thrasher as it sang thousands of songs for two hours from its perch in an oak tree. He later counted the songs and found that it sang 4,654 couplets. He then had the arduous task of printing out sonograms of each song and comparing them to see what songs were unique and what songs were repeated. Kroodsma eventually estimated that the thrasher sang about 1800 different song couplets in those two hours, but that was just one bird in one place for two hours. How many more songs did that thrasher know, or could improvise, but didn’t have time to sing? If thrashers improvise their songs, it could be true that they have an infinite array of songs.
Not long after doing this recording, Kroodsma heard two male thrashers singing in another area, the second thrasher echoing precisely every song the other thrasher was singing. He later learned of another researcher who played thrasher songs over a loudspeaker to a resident male, and that thrasher matched the tape song for song.
Kroodsma, a world-renowned expert on bird song, knows of no other songbird in the world with the ability to repeat another bird’s songs instantly. Most birds simply repeat the same song over and over, like a chipping sparrow. It’s the same song today, tomorrow and next week. Some birds have a small variety of songs they repeat, which usually occurs in a predictable pattern. But no bird comes close to the repertoire of the brown thrasher.
A last question one must ask is why? Why sing so many different songs? No answer, of course, will ever be known, but since songs are sung with the primary intent of attracting a female, perhaps the brown thrasher female has the most discriminating ear of any species on Earth. Kroodsma also allows that “I have to consider the idea that this master of the largest song repertoire known among birds is somehow enjoying himself.”
Migration Is On!
On 5/5, a birder in the Appleton area observed a “fall out” of 20 species of warblers in one hour while sitting still in one spot. Twenty-four species of shorebirds were reported on 5/6 near Madison and the Horicon marsh area. Hawks were migrating hot and heavy two weekends ago (May 1 and 2) on strong southerly winds. The hawk counter at Brockway Mountain in Copper Harbor, MI, reported over 1500 hawks coming through in a three-hours span on 5/1.
So, this is the time to keep an eye skyward for waves of warblers and hawks and whatever else a southerly breeze might bring.
Celestial Events
Planets visible at dusk in May: Venus low in the northwest, Mars high in the southwest, and Saturn high in the south. At dawn, look for Mercury very low in the northeast, Jupiter low in the southeast, and Saturn setting in the west.
On 5/16, look at dusk for Venus just below the two-day-old moon. May 17th blesses us with 15 hours of daylight. On 5/20, look for Mars about 5 degrees south of the first quarter moon. Full moon – the “Planting Moon” – occurs on 5/27. This is the year’s southernmost/lowest full moon, climbing only 18° above the southern horizon.
Drought Update
Our total precipitation so far for 2010, as measured at the Minocqua Dam at the end of April, was 2.43 inches, a deficit of 3.87 inches for the year (we normally average 6.3 inches) and down 33.74 inches since 1/1/03.
Transformation
If I had to pick the two most exciting weeks of the year to be alive, I’d pick these last two weeks of May. The plant world achieves the greatest of transformations, transitioning from a 5-month-long white-out to a full-tilt, eye-popping greenery that includes every shade of green one could imagine, emanating from literally billions if not trillions of leaves.
The neotropical songbirds arrive across the North Country by the tens of thousands, having winged their way across thousands of miles of land and water to arrive in our backyards and forests and lakes. They bring with them a riot of songs that transform every early morning into a free ticket to one of the greatest concerts on Earth. Just wake up at dawn and open the window. Better yet, take a walk as the world awakes, and soak in all the expressions of life and ardor and, if you will, joy. There won’t be another time this year when life is at this height of expression. You’ve spent, as they have, a long winter under wraps. It’s time to enjoy.
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