A Northwoods Almanac for July 6 – 19, 2018 by John Bates
Loon Update
From Walter Piper’s blog (https://loonproject.org/recent-events/): “As of today [6/30], 32 of our territorial pairs have hatched chicks [Piper is monitoring 123 pairs overall]. We are on pace with last year, despite the three-week delay in nesting resulting from the cold winter . . . 2018 looks to be at least an average year for chick production.”
Piper notes that in the past two weeks, four pairs lost their chicks. He adds, however, that “loss of chicks in the first two weeks of life is not terribly surprising. Young chicks must confront a great many challenges, including simply keeping themselves warm and avoiding physical injury as they learn to swim and move about. But the greatest hazards to hatchlings, we have learned, are strictly biological. Being tiny, having limited mobility, and with only a vague sense of the dangers posed by much larger organisms in their habitat, young chicks can be attacked and killed by a wide variety of animals — intruding loons, snapping turtles, muskies, and eagles, to name a few.”
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| photo by Bev Engstrom |
Isle Royale Update
The National Park Service gave final approval of a plan to capture 20 to 30 mainland wolves over three to five years and transport them to Isle Royale to fill the role of the apex predator.
Wolves made their way to the island in the late 1940s. Their numbers reached as high as 50, but only two remain. Inbreeding and disease are believed responsible for their recent drop-off.
Without this action, the extirpation of wolves was expected, which raised concerns about possible effects to the current Isle Royale ecosystem, including impacts of an unchecked moose population on forest vegetation communities.
Sightings - Eastern Spiny Softshell Turtle, Wood Turtle, Polyphemus Moth, Downy Woodpecker Save
Darlene Kaminski sent me a photo of an eastern spiny softshell turtle laying eggs near the Manitowish River. This is a notable sighting given that these turtles are very uncommon in the Northwoods, preferring warmer waters found further south.
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| photo by Darlene Kaminski |
Equally uncommon are wood turtles, a threatened species in Wisconsin. But on 6/1, Mary and I spotted one across the road from our home in Manitowish. We’ve lived in Manitowish for 34 years, and this is the first one we’ve seen close to our home.
Howard P. sent a photo of a Polyphemus moth that was visiting his yard in Minocqua. These moths can have up to a 6-inch wingspan, and are noted for their single oval transparent spot ringed with yellow, black, and blue on each wing. In Greek mythology, Polyphemus refers to the one-eyed giant son of Poseidon; hence the connection.
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| photo by Howard P |
The top of a tree snapped off in a windstorm and came down in the Rhinelander backyard of Sharon Gobert. This is not unusual, but the tree had a nest of downy woodpeckers inside a cavity, and Sharon and her daughter Kristen could hear the chicks calling. They thought that if they could prop the tree back up against some other trees, the mother could get back to her babies. But they couldn’t budge the tree.
The next morning, they could hear the parents call in distress because they couldn’t get to their chicks. So, Sharon and Kristen called a few friends to come over and help them lift the tree and prop it up. Kristen said the adults sat on a branch and watched this transpire, and as soon as the tree was up, the female flew in to check the chicks. Not only that, Kristen said, but the male came and perched on the wood pile next to her, looked at her and cheeped a few times as if to say “thanks so much for the help and saving our kids,” and then flew off to the nest.
Tapetum Lucidum - Eyeshine
Sarah Krembs from Manitowish Waters went out last week at dusk to listen for whip-poor-wills, and while she didn’t hear any, she instead saw one sitting on the road, its eyes glowing red in her headlights. I’ve seen this before, too, and my question has always been, “Why red?”
Whip-poor-wills, like many animals, have a mirror-like structure called a tapetum lucidumimmediately behind the retina which reflects visiblelightback through the retina. This increases the light available to thephotoreceptorsand contributes to the superior night visionof many animals.
Since whip-poor-wills hunt for insects in the poor light of dusk and pre-dawn, as well as during full moons, they need night-adapted vision. I haven’t been able to find anything in the literature which explicitly explains why their eyes reflect orange or red, but I suspect it has to do with their need to be less visible when sitting on a nest or to prevent being seen by predators at night.
Night eyeshine occurs in a wide variety of colors– white eyeshine occurs in many fish, like walleye; blue eyeshine occurs in some mammals such as horses; green eyeshine occurs in cats, dogs, and raccoons among others; while red eyeshine occurs in coyote, rodents, opossums, and birds.
Sarah would likely never have seen the whip-poor-will that night if its eyes didn’t reflect her headlights. But whip-poor-wills are also almost impossible to see during daylight, too, due to their cryptic coloration. A ground-nesting species, the eastern whip-poor-will lays its 2-egg clutch directly on the leaf litter of the forest floor. During the day, adults remain motionless on the nest or on a roost site, and you literally have to nearly step on one to see it. If you were to see one, the adults usually perform a broken-wing display like a killdeer to try to lead you away from the nest.
I find it interesting that the hatching of chicks seems to be closely tied to periods of the full moon. Eastern whip-poor-wills usually forage at dawn and dusk, but on bright moonlit nights they also catch moths and other insects throughout the night. This greater availability of food helps them meet the energy demands of their rapidly growing chicks.
According to the North American Breeding Bird Survey, eastern whip-poor-will populations have declined by almost 3% per year between 1966 and 2015, resulting in a cumulative decline of 75% during that time.The reasons for their decline include the loss of habitat to agricultural crops and grazing, the maturation of forests, better fire control, and collisions with cars while they’re feeding on or near roads at night.
I love hearing whip-poor-wills, but I also love being able to roll up my windows and leave because they call so loudly and incessantly. In one study, the birds sang approximately 59 songs per minute, or one per second, and for 15 minutes or more without pause. Some researchers have recorded them singing continuously for over 1,000 calls, and that can drive a person a little crazy.
More on the Interior Decorating Skills (or Lack Thereof) of Male House Wrens
A friend and I have been enjoyably bantering back and forth about whether male house wrens are good examples of how males in general completely lack interior decorating skills. She’s right, of course, but I feel compelled to at least partially defend my gender. Her latest shot across my bow, however, quoted this: “At times when the female bird [a house wren] disapproves of the material used by the male bird, it dismantles the nest by throwing out the sticks used by the male bird one at a time. After choosing a nesting site the female wren then takes over the construction and makes a nest cup over the pile of sticks made by the male bird. Materials used by the female wren to line the nest are soft material like feather, hair, wool, spider cocoons, strips of bark, rootlets, moss, and trash.”
Perhaps I should just concede defeat.
Flowers Currently in Bloom
Mary and I took a short walk down old Hwy. 51 in Manitowish on 7/1, and the flowers along the roadside and in the wetlands were prolific. We saw the following: joe pye weed, marsh milkweed, common bladderwort, blue flag iris, and marsh cinquefoil in the wetter areas, and in the drier areas, common St. John’s wort, daisy fleabane, daisy, bush clover, wood sorrel, common milkweed, tall buttercup, brown-eyed Susan, tall meadow rue, heal all, marsh hedge-nettle, wild mint, everlasting pea, bird’s foot trefoil, orange and yellow hawkweed, fireweed, and large white-flowered anemone, among others.
May – Warmest Ever
Almost every tract of land in the contiguous United States was warmer than normal in May, helping to break a Dust Bowl-era record. According to the National Oceanic and Atmospheric Administration, the month’s average temperature of 65.4 degrees eclipsed the previous high mark of 64.7 degrees set in 1934. The pattern presented a major contrast from April, which ranked the 13thcoldest on record. However, thanks to May’s record-setting warmth, the nation overall posted its 22nd-warmest spring (March through May) in records that date back to 1895, more than offsetting the cold April.
Celestial Events
Today, 7/6, the earth is at aphelion, or the farthest from the sun that it will be in 2018 – 94.5 million miles.
The next three weeks or so mark the average warmest days for our area, with an average high of 79°, and an average low of 55°.
On 7/10, we’ll be blessed with 15 hours and 30 minutes of daylight, down from our high of 15 hours and 45 minutes on summer solstice.
New moon occurs on 7/12. On 7/15, look for Venus after dusk 1.6° below the waxing crescent moon.
Thought for the Week
What makes a place special is the way it buries itself inside the heart, not whether it's flat or rugged, rich or austere, wet or arid, gentle or harsh, warm or cold, wild or tame. Every place, like every person, is elevated by the love and respect shown toward it, and by the way in which its bounty is received.”
― Richard Nelson, The Island Within
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