Friday, April 21, 2017

A Northwoods Almanac for April 14, 2017

A Northwoods Almanac for April 14 – 27, 2017  

Loons Returning
Over 30,000 adult loons reside in the U.S., half of which nest in MN, WI and MI. Wisconsin alone has an estimated summer population of about 4,000 adults. Of those, the Lakeland region is home to the second largest loon population in the Midwest, and they’re returning now. Up to ice-out, “our” loon pairs content themselves with overflights of their territories to look for open water. In the meantime, they wait (mostly along the Wisconsin River) the lakes to open-up, though a lake may be only partially open and the loons will still land.
Since 1991, researchers have banded over 3,600 adult loons and chicks in northern Wisconsin, providing a wealth of information on when loons leave for their autumn migration, where their migratory routes take them, where they spend their winters, and much, much more. A far smaller number have had satellite radio transmitters surgically implanted in them, allowing biologists to track their daily movements.
This extensive banding and observation of marked loons has shown that over-wintering adult survivorship is high and more than half of chicks born here return to the area as adults. Loons first return to their breeding grounds at age 2 to 4 years of age, with males tending to return nearer to their natal (birthplace) territory than females.
Both sexes tend to wander as “floaters” and use many different lakes for 2 to 3 years before either founding or acquiring a territory. Males and females both show a striking age-dependent pattern in the means they use to gain a territory: when 4-5 years old, they usually try to settle in a vacant territory with a mate and thus create a new territory. But finding a vacant territory these days is quite uncommon unless the adult pair on a lake fail to return from their winter on the Gulf.
Thus, nearly all desirable territories are already spoken for, and most younger loons have no choice but to acquire their territories by force. If the loons have not created a new territory by 6 to 8 years of age, they usually attempt to seize a territory from an established owner after a violent territorial battle. Among males, about one-third of these battles result in the death of the displaced male owner. Displaced females are more likely to leave the battle before being killed, but then typically will still need to fight to acquire a new territory. These territorial evictions are about equally frequent in males and females.
During these battles, the response of the other member of the breeding pair is stand aside. Walter Piper, who has studied loons in our area for 25 years, has observed many of these battles and has learned that females, which are about 20% smaller than males, can’t help their mate avoid eviction – they’re too small to make a difference in the battle. Their size, though, ensures they are protected. Piper notes, however, that males might be expected to help their female mate drive off a would-be usurper, yet Piper and his crew have never observed a male teaming up with his mate to drive off a potential usurper. Why not help out? Well, while loons are monogamous, they are married more to their territory than their mate. As Piper notes, “Perhaps males are better off with a mate that fights strongly (such as a proven usurper), since having a vigorous mate ensures future years of eviction-free breeding. It is a bit sad and selfish to say it, but if your mate is vulnerable to eviction, it is probably best to let her fend for herself than to intercede and save her.” Obviously, the same would also hold true for females not jumping in to help their male counterparts.

Peepers, Wood Frogs, and Chorus Frogs Singing
            It’s frog time, and as soon as we have warm nights in the high 30s and the ground thaws, spring peepers, wood frogs, and chorus frogs will emerge from their woodland hibernation and begin their breeding clamor. Fishless temporary wetlands (called vernal pools or ephemeral wetlands) are ideal for breeding – the water warms quickly and the frogs can lay their eggs in relative safety from predators.  
Spring peepers inflate their throat pouch to nearly the size of their body and use it to push air over their vocal cords, making a sound when they both inhale and exhale. Each call rises in a crescendo until collectively there is total tumult in the pond. The frogs engage in duets, trios, quartets, what one naturalist describes as “nature’s choir fortissimo.”
Peepers can be heard from as far as a mile to two away depending on the number of peepers in the chorus. And when you hear them, you can bank on spring being here, at least “spring” as defined very loosely in the Northwoods.

Mating Strategies – Don’t These Birds Have Any Morals?
            For birds, mating isn’t about sex, it’s about leaving behind a maximum number of offspring and contributing to the gene pool. So, morals don’t play into the equation. However, most bird species mate monogamously, which would appear to meet the family values test of humans. In fact, monogamy occurs in more than 90 percent of avian species. Sounds good on the surface! The problem is biologists have discovered from blood tests that chicks are often of mixed parentage, and that most species of songbirds participate in “extra-pair copulations (EPCs).” Paired males commonly copulate with other females, but females also initiate EPCs by flying into another male’s territory. So, there’s lots of hanky-panky going on, but under the appearance of a monogamous relationship. Think of various soap operas – “Days of Our Lives,” “Dallas,” etc.
            Polygamy, where a male or female pairs with two or more members of the opposite sex, occurs where birds can monopolize a desirable habitat, or one gender can monopolize a group of the opposite sex. When a male mates with two or more females, it’s called polygyny. Pheasants fit this bill, the male attracting a harem of females to his desirable territory, protecting and fertilizing them, but playing no part in rearing the young. Of North America’s 278 breeding songbirds, only 14 are polygnous - marsh wrens, red-winged blackbirds, indigo buntings, and lark buntings are other examples.
            In only a few cases, females pair with more than one male, a practice called polyandry. Spotted sandpipers, phalaropes, and acorn woodpeckers are examples. A spotted sandpiper female is larger and more aggressive than a male. She mates with one male, lays a clutch of eggs, leaves him to incubate and rear them, and then pairs with other males, repeating the process again and again. Because she mates with multiple males, the incubating males often raise chicks that belong to their competitors. Thankfully, birds don’t have custody battles and alimony – think of the legal fees.
            Then there are birds that are classified simply as promiscuous. In very good habitat, the female only needs the male for his sperm, so she chooses from a host of males happy to display themselves in the same area. For example, prairie chickens and sharp-tailed grouse mate on leks, which are tiny territories where the males gather, dance and call madly, and often fight, all in hopes they will be selected by a very discerning female. Think wild bar scene. She walks among them, considering, considering, then briefly has a fling, and off she goes to build her nest and carry out all the nesting duties, while the males continue their dancing on the lek. Older males hold territories near the center of the lek, leaving younger males to patrol the periphery and continually challenge the older males for a spot in the choice middle.
            Different strokes for different folks - it’s all about taking advantage of habitat conditions and individual reproductive strengths with the goal of advancing the species.

Sightings
3/28: Robins began their pre-dawn chorusing in Manitowish. Callie and I heard two pairs of sandhill cranes dueting in Powell Marsh.
3/29: FOY (first-of-year) Juncos and tree sparrows arrived in Manitowish.
3/30: FOY fox sparrows and rusty blackbirds returned to our backyard in Manitowish. We also spotted our FOY common and hooded mergansers on the Manitowish River.
3/31: Sarah Krembs heard the FOY American woodcock near her home in Manitowish Waters.

Celestial Events
            Today, 4/14, we’re now enjoying 13.5 hours of daylight.
On 4/16 and 4/17, look before dawn for Saturn near the waning gibbous moon.
According to Woody Hagge’s 41 years of data, 4/16 also marks the average ice-out date for Foster Lake in Hazelhurst. At 39 acres and a maximum depth of 38 feet, Foster Lake represents a relatively “average” lake in our area. In general, however, larger, deeper lakes will keep their ice longer, while smaller, shallower lakes will lose their ice earlier. Foster Lake now averages 141 days, or 20 weeks, of ice cover.
            Around 4/21, the average low temperature for the Lakeland area will hit 32°. Minocqua thus averages 182 days with low temperatures above freezing.
            The peak Lyrid meteor shower occurs in the predawn on 4/22 and averages 10 to 20 meteors per hours.
            Finally, before dawn on 4/23, look for Venus near the waning crescent moon.

Redwoods!
our daughters, Eowyn and Callie, within the redwoods
            Mary, Callie, and I flew out last week and joined our oldest daughter Eowyn for a visit to the Jedidiah Smith Redwood State Forest near the Oregon border. More on this in a later column, but this trip has likely broken the record for the number of times “WOW” has been said in any given hour. One of the old-growth redwood groves in the park totals 5,000 acres, and includes the world’s largest, though not tallest, coast redwood (Sequoia sempervirens), measuring 20 feet in diameter and 340 feet tall. These are the largest living trees on Earth along with their brethren the sequoias (Sequoia giganteium).

note the single trillium within the mosses
            John Steinbeck wrote in Travels with Charley, “The redwoods, once seen, leave a mark or create a vision that stays with you always. No one has ever successfully painted or photographed a redwood tree. The feeling they produce is not transferable. From them comes silence and awe. It's not only their unbelievable stature, nor the color which seems to shift and vary under your eyes, no, they are not like any trees we know, they are ambassadors from another time.”
           
Thought for the Week
            “Fueled . . . by a million wings of fire the rocket tore a tunnel through the sky and everybody cheered. Fueled . . . only by a thought from God, the seedling urged its way through the thickness of black and, as it pierced the heavy ceiling of soil and launched itself up into outer space . . . no one even clapped” – Marcie Hans. Let’s remember to clap.
           
Please share your outdoor sightings and thoughts: call 715-476-2828, e-mail at manitowish@centurytel.net, snail-mail at 4245N Hwy. 47, Mercer, WI, or see my blog at www.manitowishriver.blogspot.com


Thursday, March 30, 2017

A Northwoods Almanac for March 31, 2017

A Northwoods Almanac for 3/31 – 4/13, 2017  

Sightings
3/13: The bald eagle pair that nests across the Manitowish River from our house began incubating eggs today. The activity around the nest now involves an eagle flying in and settling down into the nest, while another one emerges from lower in the nest and flies off. Bald eagles share the incubation of their eggs, so this trading of tasks is regular throughout the day. Incubation typically lasts around 30 days, so we expect to see the activity around the nest change again around April 13 when they will then be tasked with feeding the chick or chicks. This is, by the way, an early date for nesting – the average date is closer to April 1. Bob Kovar in Manitowish Waters also reported that the eagle pair nesting on his property began incubating the same day.


3/17: Our FOY (First-Of-Year) red-winged blackbirds returned to our feeders in Manitowish, as did an American tree sparrow.
3/23: Our FOY white-throated sparrows returned to Manitowish.
3/24: Nancy Burns spotted the FOY hooded mergansers on the Manitowish River.
3/25: Sharon Lintereur in Lake Tomahawk saw movement in their owl nesting box, and it turns out that for the second consecutive year, a pair of barred owls are nesting there. Barred owls nest most often in deciduous trees, primarily in cavities formed by disease, broken branches, or cavities in the top of broken trees (snags). However, they will use open stick nests built by hawks, crows, ravens, or squirrels, too. They also readily take to nest boxes, as is the case at the Lintereur home. Incubation is done solely by the female and is usually about a month, with an average clutch size of 2 to 3 eggs. If more than 3 eggs are laid, each on successive days, the youngest of the brood often is underweight and weak, and may be eaten by its nestmates.

photo by Sharon Lintereur
3/25: Mary and I spotted our FOY common goldeneyes, red-breasted mergansers, and common mergansers in Marquette, MI, on Lake Superior.
3/27: Our FOY common grackles appeared at our feeders in Manitowish.

On the Horizon
            Numerous species of birds have migrated into southern Wisconsin and most are poised to continue their flights into the Northwoods as the weather warms. Keeping records on when various species return is all part of phenology, or the study of the orderly timing and progression of natural events. Others define it as the study of biological cycles and seasonal rhythms. It’s nature’s calendar. I encourage you to keep a calendar of your first sightings, from ice-off on your lake, to the first birds and flowers, to various temperature and rainfall recordings. Relying on our memories, at least for those of us without photographic memories, is a sure way to ruin otherwise. Then pass on your records to the next person who will own your home, so they know what to look for and when.

Five Drummers Drumming
            Woodpeckers are beginning to drum regularly on trees around our home, the males now establishing territories and beginning to woo a mate. If you pay attention to the duration, speed, and volume of the drumming, you can identify the species by the drum pattern. We only have five common woodpeckers in our area – pileated, hairy, downy, northern flicker, and yellow-bellied sapsucker – so it’s not too daunting. You may also hear red-bellied woodpeckers which continue to slowly move north into the Lakeland region, as well as red-headed woodpeckers which have become less common. And if you are particularly blessed, you could hear a black-backed woodpecker. But we are at the southern-most edge of their range, and they’re rare.
            The drumming for territories and mates is different from that of the arrhythmic tapping heard from woodpeckers as they excavate nests and search for insects. The drumming from yellow-bellied sapsuckers is an easy one to start with because it starts strong with several relatively fast taps, then slows down, and finally fades out at the end. It can be very irregular, often changing in successive drumrolls – you can think of it as a Morse code: Tap-Tap-Tap…tap-tap-tap . . . tap . . . tap . . . tap.
            The pileated is the power drummer of the crew, pounding out a crescendo that is deep and resonant, lasting for three seconds or more. Both genders drum, but the females less frequently. Famed ornithologist George Sutton described the sound as a repeated sequence of “an introductory, rapidly given ; then a pause, followed by three distinct blows; another pause; and two concluding blows.” It’s the volume that gives this one away without a doubt, and you can literally hear the hollowness of the tree.

pileated chicks in nesting cavity

            Things get a little dicier now in identifying the drumming patterns. The drumming of northern flickers has been described as “a miniature pneumatic drill,” produced by even, rapid blows. The drum roll only averages a little more than a second long, but contains 25 beats in a roll. Like many woodpeckers, flickers will often drum on a metal surface. One flicker in Wyoming beat on the cowling of an abandoned farm tractor and could be heard almost a half-mile away.
            The hairy woodpecker drums at a relatively steady rate, but more rapidly and with longer pauses than the downy woodpecker. Its drumroll lasts about a second and has 26 beats – it goes by so fast that you can’t pick out the individual taps – whereas a downy’s drumroll lasts three-quarters of a second and averages 13 beats. Here you can just pick out each tap.
The downy also loves to drum more, offering 9 to 16 drumrolls a minute versus the less enthusiastic hairy which only drums 4 to 9 times a minute.
Both sexes drum in all these species for a variety of reasons:
1.     To defend a territory
2.     As part of a courtship
3.     To solicit copulation
4.     To summon a mate from distance away
5.     To communicate their location to a mate or in response to a nest intruder
6.     Or for reasons no one will ever know
            Drumming does occur year-round in woodpeckers, but it’s much more intensive in spring. While species identification from drumming can be done with practice, if I had a nickel for every misidentification I’ve made of birds, I’d be a wealthy man.

Saw-whet Owls Calling
I’ve yet to hear a saw-whet owl “singing,” but now is the time to go out after dark and listen for their monotonous tooting. While saw-whets produce a series of different calls, the one most often heard is the “advertising call,” which is an endless loop of whistled “toots” on a constant pitch. The call comes at a rate of about two per second and sounds, and when researchers say it’s monotonous, they really mean monotonous – the song can literally go on for an hour or more.

saw-whet owl range map


Celestial Events
            Jupiter will be at its closest to the Earth on 4/7 and brighter than at any other time this year, and is also visible all night. You should be able to see Jupiter’s four moons with a good pair of binoculars. If you can’t, this is a good excuse to buy that spotting scope you’ve always wanted – see www.eagleoptics.com. The moons are often called Galilean moons for Galileo who discovered them in 1610.
            Galileo was employed by Cosimo de’ Medici, the Grand Duke of Tuscany. In seeking further patronage from this wealthy family, he used the discovery of the moons to name them the “Medician Stars” after the Medici Clan. He wrote a dedication letter to the Duke in which he said, “Scarcely have the immortal graces of your soul begun to shine forth on earth than bright stars offer themselves in the heaven which like tongues will speak of and celebrate your most excellent virtues for all time. Behold, therefore, four stars reserved for your illustrious name . . .” It occurs to me this practice continues in our time, but is used to gain money by naming stadiums after corporations, not moons after Dukes.
On 4/10, look for Jupiter in the southeast just two degrees below the nearly full moon. Full moon occurs the next day, 4/11.
For planet viewing in April, look after dusk for Mars very low in the western twilight – it’s lost by late-month. Jupiter is very bright in the southeast. Before dawn, look for Venus very low in the eastern twilight and climbing. Look also for Saturn in the south (Saturn rises after 1 a.m. in the ESE if you are wandering around at that hour). Saturn’s rings are tilted at nearly 27 degrees from edge-on.
            April 12 marks the anniversary of the first human in space – Yuri Gagarin in 1961 from Russia – when the race for space really heated up.

Thought for the Week
“Wisdom grows as a river grows, from the accumulation of many small things.” Kathleen Dean Moore     
             
Please share your outdoor sightings and thoughts: call 715-476-2828, e-mail at manitowish@centurytel.net, snail-mail at 4245N Hwy. 47, Mercer, WI