A Northwoods Almanac for May 13 - 26, 2022 by John Bates
Sightings – Double-crested Cormorants, White Pelicans, Trumpeter Swans, Ice-Out
Greg and Dawn Holt reported seeing a flock of at least 60 double-crested cormorants on Benson Lake in Manitowish Waters on April 24. They noted, “The cormorants hung out in one of the bays for about half an hour and then all flew off up river. We'd never seen that before.”
Cormorants are usually associated with much larger water than tiny Benson Lake, so this was quite unusual.
The next day, 4/25, I hiked out on the main dike at Powell Marsh and saw one cormorant, but the most exciting observation occurred when four white pelicans flew low over my head and then landed on the back pool. They loafed and fed there for the hour that I spent scoping other waterfowl, which included trumpeter swans, buffleheads, American wigeons, gadwalls, redheads, hooded mergansers, a hundred or more ring-necked ducks, blue-winged teals, green-winged teals, American coots, mallards, Canada geese, and sandhill cranes.
A few days later, I counted 28 trumpeters at Murray’s Landing on the Turtle-Flambeau Flowage.
Woody Hagge on Foster Lake in Hazelhurst noted that the ice went out on the lake on April 29, which ties the record for the fifth latest ice-out on the lake in the 50 years he’s kept records. We noted that the ice went out on nearby Frog Lake on the same date. However, as of this writing on May 5, a number of our largest lakes remain ice-covered. All of this will finally change with the advent of 65° weather.
Mary, Callie, and I spent May 1 – 4 along the North Shore of Lake Superior, and we heard that up in the Boundary Waters, the ice on the most of the lakes was still 20 inches!
Spring Ephemeral Wildflowers
Spring flowers are coming! In early May in rich maple-basswood forests, bloodroot blooms in an ephemeral symphony with trout lilies, hepaticas, and spring beauties. Bloodroot doesn't deign to dip its roots in the sandy pine soils around our home, but patronizes only dark-soiled and deeply shaded hardwood understories.
Usually just one waxy white flower rises 6 to 10 inches with eight showy petals embellished with numerous golden-orange stamens. If picked, the flower almost immediately closes or the petals drop. The petals expand flat in the morning, become erect by late afternoon, close by evening, and are sensitive to weather changes, closing up when it's cold or cloudy.
The lower part of the stem is sheathed, and the single, smooth large leaf is rounded with 5 to 9 lobes and a conspicuous cleft at its base. The leaf curves upward and inward like a cupped hand.
Bloodroot is truly an ephemeral flower, living only a few days to a week, but attracts many insects, mostly bees, to gather pollen (though they find no nectar).
Bloodroot is a card carrying member of those plants who employ the “stable-habitat strategy” of flowering. Stable-habitat plants put little energy into creating fruits attractive to birds and mammals, because over time their habitat remains generally uniform. They, unlike annuals and perennials found in disturbed habitats, don't need to produce masses of seed to spread to newly exposed areas in order to ensure their survival the next year. Instead, they invest most of their energy in leaf, stem, and root growth to maximize their winter survival into the next spring. Thus, bloodroot has evolved a thick, finger-size rootstalk that stores up nutrients in order to rush the flower into bloom in early spring.
The rootstalk and the flowers stems all bleed a vivid red when broken, hence the common name of bloodroot as well as the genus name, Sanguinaria, which means “bloody.”
The seeds of bloodroot, spring beauty, and several violets all bear elaiosomes which contain certain lipids that ants can't get from other foods. The ants gather the seeds and feed them to their larvae, meanwhile dispersing them well away from the fruiting plant. The leftover seed is dumped in the colony garbage dump, a sort of mini-compost heap that is rich in nutrients and moisture, providing an ideal site for germination.
This is a form of “mutualism,” a relationship between two species in which both benefit. Without the work of ants, the profusion of bloodroots and other flowers like trilliums that one often finds in a woods would be dramatically reduced. If you like fancy terms, this seed farming by ants is called “myrmecochory.”
Bears Awakening and Are Much Lighter
Bears are out of their dens by now, but are a much thinner version of themselves after this long winter. Dr. Lynn Rogers in Ely, Minnesota, keeps close tabs on several bears near his wildlife center, and this year noted that the adult sow showed up on April 22 with her two yearling sons. One yearling weighed 62 pounds, the other 57 pounds, while the sow weighed 180 pounds. Six months ago on October 21, 2021, their respective weights were 84, 75, and 343.
That means the sow lost 48% (163 pounds), and the two yearling lost around 26% (22 and 18 pounds).
The sow, however, would not have been nursing the yearlings, so her weight loss can’t be ascribed to that stress. Rogers notes that some well-fed mothers continue to lactate in the den, and he wondered if the sow’s high weight loss over those 185 days (0.88 pounds per day) was due to that.
Sturgeon Spawning
Lake sturgeon will soon be spawning on the Manitowish River and the North Fork of the Flambeau. Sturgeon, a truly prehistoric fish species, spawn every year once water temperatures reach at least 50 degrees. Spawning, however, is dependent on both water temperature and water flow. During seasons when water flow is high and water temperatures rise slowly, spawning begins when the water temperature reaches 53°F. In contrast, during seasons of low water flow and more rapid water temperature rise, spawning does not begin until water temperatures reach 58° to 59°F.
Female sturgeons only spawn every 3 to 5 years, and then only when they reach maturity between 20 to 30 years old. Male sturgeons, on the other hand, spawn every other year once they mature at 15 years old.
Males arrive ahead of the females, often in groups of eight or more, frequently cruising so close to the surface that their tails, backs, and snouts are out of the water. When a ripe female enters the group, spawning begins. As she drops her eggs, the males swim alongside her and thrash their tails as they release milt (sperm). The one-eighth inch diameter fertilized eggs are sticky, and cling to the rocks until they hatch some 10 days later.
Even though one female may produce from 50,000 to 700,000 eggs, sturgeon remain rare because the eggs are eaten by crayfish, redhorse, carp, and even the adult sturgeon. Or they are lost to dropping water levels, or to a fungus that can grow on the masses of eggs. Less than one in a thousand eggs will survive to the one-third inch-long larval stage.
Females live longer than males and grow to astounding sizes. Some 97 per cent of all sturgeon over 30 years old are females. A 152 year old, 215 pound, 81 inch long sturgeon was caught in 1953 in Lake of the Woods, Ontario. The Fond du Lac Journal in Wisconsin reported the capture of a 9 foot long, 297 pounder in the spring of 1881.
They not only live long and grow huge, they swim enormous distances. A five-foot lake sturgeon caught in commercial fisherman's net in Saginaw Bay in November of 1994 was traced by its aluminum tag to be from Lake Winnebago, 450 miles by water from the spot it was caught and tagged on 10/20/1978 by the Wisconsin DNR. It had navigated the lower Fox River which has 14 dams and 17 locks on it before reaching Green Bay, and then wandered through Lake Michigan, the Straits of Mackinac, into Lake Huron, and finally down the east coast of the Lower Peninsula to Saginaw Bay. In those sixteen years, it had grown 8 inches, which is an average rate of growth for sturgeon.
Another sturgeon was taken in Lake Erie five years after it had been tagged in Lake Winnebago, a distance of 850 miles away.
While huge in size and shark-like in appearance, they are absolutely placid, and have been known to swim with and among humans – they're “harmless as a wet log,” says one writer.
The Ojibwe know the sturgeon's importance. They call it nah ma – “king of fishes.”
Follow Bird Migration in Your County!
A new online tool provides summaries of radar-based measurements of nocturnal bird migration, including estimates of the total number of birds migrating, their directions, speeds, and altitudes. The “BirdCast Migration Dashboard” depicts migration patterns in near real time or as a summary of a whole night. This includes additional historical information (2013-2021) as well as previous nights’ movements. The counter tracks the total number of birds estimated to have overflown an area since the start of a night (e.g. between local sunset and sunrise).
Note that the dashboard currently provides data for states in the contiguous US, but you can also enter your specific county, and a whole host of graphs and charts will appear. For instance, on the night of 4/28-29, BirdCast estimated that 470,300 birds crossed my home county of Iron, and 508,300 birds crossed in Vilas. Remarkable!
Go to: https://birdcast.info/migration-tools/migration-dashboard/
Celestial Events – Lunar Eclipse!
For planet watching in May, look before dawn for Venus and Jupiter in the SSE, Mars in the SE, and Saturn in the ESE.
The full moon occurs on 5/15, and a total lunar eclipse occurs that same night. Partial eclipse begins in our area at 9:27, with total eclipse beginning at 10:29 and ending at 11:53. The whole shebang comes to a close on 12:55 a.m. as the moon exits the Earth’s shadow, though the penumbral eclipse, a light shadowing, continues until 1:50 a.m.
We’re up to 15 hours of sunlight as of 5/17.
Look before dawn on 5/24 for Mars and Jupiter about 3 degrees above the waning crescent moon.
Thought for the Week
“Have holy curiosity.” – Albert Einstein
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