A Northwoods Almanac for 2/14-27/2025
Valentines Day
Valentines Day has always been about the heart, but not all hearts are the same. Some hearts beat fast, and some beat slow. When they’re flying, hummingbirds win the Olympic race for the fastest heartbeat at 1200 beats per minute, or 20 beats per second. For comparison, at rest human hearts beat around 70 times a minute (4,200 times per hour, 100,000 times per day), but when we exercise hard, we can up our rate to 150 beats per minute.
Hummingbirds not only have the fastest heart rate, they also have the largest hearts relative to body size in the entire animal kingdom. Their hearts account for as much as 2.5 percent of their body weight, compared to a human heart, which only accounts for 0.3 percent of our total body mass. Keep in mind that the total weight of a hummingbird is about the same as a U.S. penny – a tenth of an ounce. Well-known writer and birder Laura Erickson rightly notes that you could mail nine or ten hummingbirds with a single stamp. At 2.5% of that, a hummingbird’s heart only weighs 0.0025 of an ounce.
Or . . . basically nothing.
Still, a hummer’s heart is proportionately five times larger than ours, and all things being relative, that’s pretty darn big.
The largest heart in the world, in case you’re wondering, lives inside a blue whale, weighing around 400 pounds (similar in weight to a small piano), and measures 5 feet long by 4 feet wide by 5 feet tall.
On the terrestrial side of things, the heart of the world’s largest land-based creature is that of an African elephant, but its heart “only” weighs 30 pounds.
We mammals have hearts with four chambers; reptiles and turtles have three chambers; fish have two; and insects and mollusks have one chamber.
As you can imagine, every creature has a unique heart. So, here’s your useless, but amazing, trivia stumper for the week: How many hearts does an earthworm have?
Well, an earthworm has five pairs of heart-like structures, but it depends on your definition of a “heart” – earthworms can be said to have either 5 or 10 hearts if you are flexible with your definition, or zero hearts if you’re inflexible.
One of my favorite writers, Brian Doyle, says, “Every creature on earth has approximately two billion heartbeats to spend in a lifetime You can spend them slowly, like a tortoise, and live to be two hundred years old, or you can spend them fast, like a hummingbird, and live to be two years old.”
All of this matters not one whit to the metaphor we attach to the heart, which is love.
And no one knows how to measure that.
Chippies
Eastern chipmunks are quietly ensconced in their burrows for the winter, enjoying life in the light sleep of torpor and occasionally waking to eat from their stored cache of seeds. Unlike true hibernators who spend the fall eating gluttonously in order to put on as much fat as possible to get through the winter, chippies store the energy they’ll need for the winter via collecting and storing food away in their burrow. They’re hoarders, stuffing up to 8 pounds of seeds and nuts in their tunnels and burrow – they’d make a fine subject for an episode on the television show “Hoarders!”
Chippies not only hoard food in their burrow, they engage in “scatter hoarding,” caching stockpiles of food in various other outside locations in case they run out of food in their burrow.
We’ve all seen them at our bird feeders during the fall stuffing their incredibly large, stretchy cheek pouches, each the size of their skull, with seed. They not only use their pouches to transport food, but also for removing soil while digging out their burrows – who needs a wheelbarrow?
University of Vermont biology professor Bernd Heinrich found that he could easily stuff 60 sunflower seeds in one cheek of a road-kill chippy. Thus, a chippy can carry 120 seeds in one foray.
Another researcher found in one chipmunk’s cheek pouches 31 kernels of corn, 13 prune pits, 70 sunflower seeds, 32 beechnuts, and 6 acorns.
As for their living quarters underground, the main tunnel runs from 10 to 30 feet long with several granaries off to the sides. The two-inch diameter tunnels are typically 18 to 36 inches deep into the ground. The burrow usually has one unobstructed entrance with the opening of other tunnels that lead to the surface plugged with leaves. The sleeping chamber itself is six to ten inches in diameter and lined with leaves, grasses, and thistledown. Comfy!
For drainage, narrow tunnels are dug at the bottom of the burrow to carry water away. However, researchers haven’t found evidence of a latrine inside of the burrow, so perhaps chippies have to exit their burrow now and again? No one is sure.
Chippies emerge from torpor when they’re triggered by warming temperatures and food availability, but it takes about one hour to do so. So, don’t be surprised to see a chipmunk bounding through the thawing snow on a mild winter day in March.
20th Year Anniversary of the 2005 Great Gray Owl Invasion
The winter of 2004-2005 was noted for the extraordinary invasion of great gray owls into Minnesota and Wisconsin. Over 5,000 owls were estimated to have come down into Minnesota and Wisconsin from Canada, an aberration that had never been seen in living memory and couldn’t be found in any historical writings. An “average” winter, for comparison, would have of at most 35 great grays.
The Minnesota DNR eventually released figures saying 750 dead great grays were collected (mostly along roads), and those were only the reported ones.
Steve Wilson of the Minnesota DNR said it best about the rarity of this flight, "This is the Haley's comet of the bird world."
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| Great Gray Owl range map |
Callie and I drove to Superior on January 10, 2005, to see for ourselves. We arrived at 2:40 in the afternoon, and by dusk at 5:00, we had seen 22 great grays and one hawk owl. If we had had more time to drive the roads in the area, I suspect we would easily have turned up another dozen.
In one five-minute span right at dusk, we saw eight great grays, and at one point, we watched three great grays within 100 yards of one another.
That was as remarkable of a birding adventure as I’ve ever been on.
This winter only a handful of reports of great gray owls have come in from northern Wisconsin, though several hundred have been reported in northern Minnesota.
Update on HWA
I recently watched a Zoom presentation on hemlock wooly adelgids (HWA) given by Dr. Scott Salom from Virginia Tech’s Entomology Department, and there appears to be hope on the horizon for the survival of eastern hemlocks. If you’re not familiar with HWA, it’s a tiny insect from Asia introduced in a garden in Virginia in 1951, which has since spread north and south along the East coast killing millions of eastern hemlock trees. It’s currently on our doorstep in western Michigan, and when it arrives, it will cause profound mortality in our hemlocks.
Scientists have spent the last 30 years trying to figure out what can be done to control the insect, and they’ve found a good chemical control, but the problem is that it must be used on individual trees, which is highly impractical for use in large forests.
The key instead is to find a biocontrol, some organism(s) that is native or can be introduced, and which can live and reproduce over years, while killing the adelgids without causing other unintended impacts.
A tall order.
Two beetles, one native (Laricobius nigrinus) and one from Japan (Laricobius osakensis) have been found to have a significant impact during one of the two stages of the life cycle of HWA, but unfortunately not the other stage.
Researchers are now researching and releasing silver flies (Leucotaraxis piniperda and argenticollis – both native species!) to try and impact the second life stage, but so far they aren’t seeing long-term reestablishment of them, so more work is needed.
Eastern hemlocks are germinating and growing from seed in areas hard hit by WHA, so there’s still hope. When asked directly what the future looks like for eastern hemlocks, Salom said, “I’m not discouraged at all.”
For me, that was a thrilling statement, as well as further evidence of how important funding scientific research is to our forests.
Sightings
On 1/24, Holly Nash in Hazelhurst sent me a photo of a northern shrike in her backyard, and noted, “Not surprisingly, there were no other birds in sight!”
If you’re not familiar with the diet of northern shrikes in winter, they prey on mostly small mammals like voles, mice, and shrews, as well as songbirds. They typically take smaller birds like pine siskins and American goldfinches, but can capture birds similar in size to them like a robin and even larger like a mourning dove. If your backyard birds see a shrike in the vicinity, they scatter quickly or freeze stock still at your feeders.
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| northern shrike, photo by Holly Nash |
Shrikes are always uncommon, but they seem even more so this winter. From a backyard birds’ perspective, that’s good news worth shouting.
Winter irruptions of shrikes are common, with peaks generally occurring every 3 to 6 years, but the reasons for such movements aren’t understood.
Great Backyard Bird Count
The 27th annual GBBC will be held Friday, February 16, through Monday, February 19. Each checklist submitted during the GBBC helps researchers at Audubon, the Cornell Lab of Ornithology, and Birds Canada learn more about how birds are doing, and how to protect them and the environment we share. Last year, more than 300,000 participants submitted their bird observations online, creating the largest instantaneous snapshot of global bird populations ever recorded.
The GBBC is a free, fun, and easy event. Participants are asked to count birds for as little as 15 minutes (or as long as they wish) on one or more days of the four-day event and report their sightings online at birdcount.org. Anyone can take part in the GBBC, from beginning bird watchers to experts, and you can participate from your backyard, or anywhere in the world.
Please visit the official website at birdcount.org for more information.
Thought for the Week
A few lines from a poem by Andrea Gibson:
“In the chemo room, I wear mittens made of ice so I don’t lose my fingernails. But I took a risk today to write this down.
Wasn’t it death that taught me
to stop measuring my lifespan by length,
but by width? Do you know how many beautiful things
can be seen in a single second? How you can blow up
a second like a balloon and fit infinity inside of it?”
Please share your outdoor sightings and thoughts: e-mail me at johnbates2828@gmail.com, 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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