A Northwoods Almanac for 9/1-14/23
Nighthawks
Tim Kroeff emailed me on 8/18 with a sighting of a flock of nighthawks migrating over a lake in the Mercer area.
Two days later (8/20), I saw a posting by Eric Bruhnke, an ace birder who has worked as an interpreter for six seasons at Hawk Ridge Bird Observatory in Duluth, Minnesota; counted migrating raptors at the Corpus Christi HawkWatch in Texas in 2015; and was the 2016, 2017, and 2018 hawk counter at the Cape May Hawkwatch in New Jersey, among other things he’s done. Eric described a “lifer” experience of seeing and counting more nighthawks than he’d ever seen in one day. That evening he counted 18,695 nighthawks in just under 3.5 hours flying over his backyard along the North Shore of Lake Superior in Duluth. He noted that “late August is prime time for seeing these birds migrate through the Duluth area” and that hot, calm conditions increase insect hatches, which attract insectivorous birds like nighthawks. He wrote, “There were times when I found myself getting watery-eyed while clicking them [off], being just delighted at the spectacle, with each one erratically meandering and feeding among each other.”
His tally would seem impossible to top, but on August 26, 1990, one experienced counter, Mike Hendrickson, tallied 43,690 in a two-and-a-half-hour period from a vantage point north of Duluth.
More locally, three days later on 8/23, Bob Kovar on Wild Rice Lake in Manitowish Waters called me to say he was watching 50 to perhaps 100 or more nighthawks swirling around in the air above his dock. So, I hightailed it over there and found him not at his home, but trying to photograph the nighthawks careening over one of the nearby cranberry dikes. \
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| nighthawk photo by Bob Kovar |
If you’ve not watched nighthawks feeding on an insect hatch before, you would find it just as hard to photograph them as Bob was finding it. Nighthawks erratically bob and weave and dart, a bit like a bat or a moth in flight, as they swoop through the air literally trawling for insects.
Nighthawks fly with their mouths open and scoop insects in. They do this because that’s all they can do. Nighthawks aren’t hawks. They don’t wield lethal talons, but rather have flat feet that are very small and weak. Rather than killing prey with their beak or claws, a nighthawk simply flies straight into bugs with its mouth and throat wide open. Laura Ericson, well-known birder and author, writes: “This is fast enough that insects go straight down the hatch, meeting their deaths by contact with internal digestive juices rather than external killing structures. The nighthawk’s tiny vestigial tongue set at the very back of its mouth probably has little or no tasting function; food whizzes past too quickly to rest on the tongue and too fast for the bird to reject at the last moment if it doesn’t like the taste.”
Laura worked for many years to rehabilitate injured birds, including nighthawks, and notes, “On the ground, the most succulent moth could walk right in front of the hungriest nighthawk, barely a millimeter from its beak, and the bird could do nothing but watch, hoping that the moth would walk in.”
She was amazed at how helpless they were to feed themselves when not in flight. “When I first received a [injured] bird, I’d have to tease the fragile mouth open to place food inside. Within days, most birds would run up to me, mouths open, to be fed, but no matter how long I had one, I could never teach it to feed itself. This was not because nighthawks lack intelligence but because they lack the physical structures necessary for self-feeding on the ground . . . And even after nighthawks learn to open their mouths to be hand-fed, many adults can’t swallow food items on their own for days or weeks longer.”
Nighthawks migrate a great distance between their breeding range and their wintering grounds in South America, making their flight one of the longest migration routes traveled by any North American bird.
Fall departures begin in July in both northern and southern portions of the breeding range in the U.S. and Canada, and individuals become quite gregarious during fall migration with flocks of 1,000's not uncommon. Records indicate that transients pass through Colombia and Venezuela, and then head east of the Andes to reach their primary wintering grounds.
Loon Story
Mary and Steve Ales own property on Stearns Lake, and emailed me with this story: “We were fortunate to have two loon chicks born on the lake, likely in early July. We've watched them grow and as of 7/15 there were still 2 chicks.
“[We returned on] 7/30, and we now have 3 chicks. One is clearly a bit smaller than the other two, but it's out and swimming around and diving.
“We've done some internet sleuthing and this seems pretty unusual to have a clutch of three, let alone this mysterious arrival of the third. We don't think it is an adoption as we've never seen another pair on the lake consistently. And given the parent's behavior on 7/15, we don't think that they were sitting on a nest.”
They asked me what I thought happened.
I didn’t know, so I suggested they contact Walter Piper who has done loon research on our local lakes for 31 years. His response was this according to Mary: “The answer seems to be one of two scenarios. Either something happened to the parents and the loon [chick] walked to our lake to find its new family, or there was an additional breeding pair that tried to set up home on Stearns Lake, and those parents were driven off by the resident nesting pair. Dr. Piper has seen both scenarios. The good news is that the family accepted the younger chick and everyone seems to be a happy family of five. However it happened, it was an unusual occurrence. We feel honored to have witnessed this.”
Hikes in State Natural Areas (SNA) and Federal Research Natural Areas (RNA)
Over the last several weeks, Mary and I led hikes in Doering Woods SNA, Tucker Lake Hemlocks SNA/RNA, Frog Lake SNA, Scott Lake/Shelp Lake SNA, Giant White Pine SNA, and cancelled but scouted Lake Laura SNA and Lake Alva SNA.
We love doing these hikes because of all the exceptional people we meet on the trips, but also because of some of the unusual things we see. I’ll just share two. We found what I think was the largest shelf fungi, an artist’s bracket (Ganoderma applanatum), that we’ve ever seen. I measured it at 29.5 inches across, and it looks a bit like an ocean stingray with its wavy brim. Cora Mollen’s and Larry Weber’s book Fascinating Fungi of the Northwoods says that one of these can live for as long as 50 years. Given the size of this one, I imagine it could be at least this old.
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| artist's bracket, photo by John Bates |
The other unusual item we found was a large mass of “scrambled egg’ slime mold. The Fascinating Fungi book says of this species, “As slime molds do, it first moves in amoeba-like fashion, engulfing nutrient including bacteria and organic matter. Finally, it migrates to a favorable spot for spore dispersal and forms its characteristic soft, yellow molds. At maturity, these become crusty and disintegrate, freeing their spores.”
scrambled egg slime mold, photo by Mary Burns
Yes, slime molds move. They ooze through their habitats – soil or woody debris for instance – and eventually stop to metamorphosize into their fruiting bodies.
They’ve even been shown to think and solve problems. Placed in a maze, they can find their way directly through the maze to a food source.
Trivia Time: Why is a Moose’s Nose So Big?
I’ll bet everyone has wondered why a deer has a relatively short nose while a moose has a long one. Well . . . maybe none of you have ever wondered about this, but I have, so here’s the answer courtesy of the Alaska Science Forum and a scientist from Ohio, Lawrence Witmer..
Before Witmer’s study, scientists had speculated that a long nose could help a moose shed heat from its huge body. Witmer found this adaptation unlikely because few blood vessels exist near the outside surface of a moose’s nose.
Another reason a moose might have a big nose is to better sniff out predators or potential mates. Like a person’s ears, a moose’s large nostrils point opposite directions which might help moose to better locate smells. Moose may in fact use their unique nostrils for directional smelling, but Whitmer determined that it’s most likely that the moose utilize a set of valves that close automatically underwater.
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| moose illustration by Rebecca Jabs |
Most animals like horses, dogs, and cats and other members of the deer family can’t close their nostrils, but it’s a common aquatic adaptation. Whitmer figured out that when a moose dips its head under water, the difference between the water pressure and the air pressure causes the nostrils to close. This adaptation allows a moose to feed on underwater aquatic plants without water flooding into its nose.
Climate Change Stats for China and the U.S.
China has led the world in annual carbon emissions since 2006, and currently produces more than double the carbon emissions of the U.S. However, per person the U.S. emits twice as much carbon dioxide as China does. China has 1.4 billion people, the U.S. 334 million.
The United States has reduced its annual carbon emissions over the last 25 years, largely because of the power sector’s shift from coal to natural gas and stricter environmental regulations, while China’s emissions are rising. But on a cumulative basis, America has still pumped far more carbon dioxide into the atmosphere than any other country since preindustrial times. To date, the U.S. has emitted 20% of the worlds CO2, and China 11%.
China is projected to surpass the United States as the biggest historical emitter, but not until 2050. Until then, America will continue to hold that distinction.
Meanwhile, China is leading on developing renewable energy, producing far more wind and solar power than the U.S., and has the biggest electric vehicle market also by far.
Bottom line: neither country is cutting enough carbon or making the transition to renewables fast enough to limit warming to 1.5°C (2.7°F).
Celestial Events
For planet watching in September, look after dusk for Saturn in the east-southeast, and for Mars very low in the west. Before dawn, look for Venus high in the east and Jupiter in the south. Look on 9/4 for Jupiter about 3° below the waning gibbous moon.
Thought for the Week
A home is not simply a building; it is the shelter around the intimacy of a life . . . The inner walls of a home are threaded with the textures of one's soul, a subtle weave of presences. If you could see your home through the lens of the soul, you would be surprised at the beauty concealed in the memory your home holds . . . Where love has lived, a house still holds the warmth. Even the poorest home feels like a nest if love and tenderness dwell there. – John O’Donohue
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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