NWA 8/23/13

A Northwoods Almanac for August 23 – September 5, 2013   

Hummers Beginning Migration

Late August marks the beginning of migration for ruby-throated hummingbirds. Many people have contacted me recently saying that large numbers of hummers are congregating at their feeders and “tanking up” for their push south. Male hummers precede the females in both the spring and fall migrations, while the juveniles of both sexes lag behind the departure of the adult females in the fall. Telling an adult female from a juvenile is very difficult, so most of us won’t know which is leaving, but the last to go, usually around mid-September, will almost certainly be a juvenile. Some males, on the other hand, may leave as early as the end of July.

The juveniles do not follow or fly with an adult. They find their own way, a perilous journey of a thousand miles or more into Central America, landing somewhere between Mexico and Panama. According to banding studies, most don’t survive to return the following year.

 Their migration appears to take place after the passage of a strong cold front followed by a northwest wind, a tailwind, which makes obvious good sense for a bird that weighs only 1/10^th of an ounce. Migration takes place overland during the day, and most migrants are seen during the midday hours, a likely indicator that the birds must “refuel” in the early morning hours before undertaking a long flight.

Before migration, hummingbirds feed heavily and often, doubling their weight and gaining fat to fuel the journey. Their overland migration is nearly synchronous with the peak flowering of jewelweed (Impatiens capensis), indicating that this flower is a very important nectar source and may influence the timing of migration.

To go from Wisconsin down to the Gulf Coast of the United States takes 3 to 5 days, assuming no stopover vacations for the hummer. To fly the 500-mile-distance across Gulf of Mexico takes another 18 hours if the weather is good, or 24 hours if the weather is unkind, so add another day. And then it takes another couple of days to reach its winter home in Central America. So, with no intervening rest stops, it would take a Wisconsin hummer a little less than a week to reach its wintering grounds. In reality, however, it usually takes about 2 weeks, since hummers spend time along the way feeding, resting, and waiting for good weather. Some choose to not cross the Gulf, but instead follow the coastline of the Gulf of Mexico, a decision made by individual birds for reasons that remain a mystery.

Remarkably, although the ruby-throated hummingbird is widespread and much-loved, many fundamental aspects of its migration and breeding ecology remain poorly understood.

Leave your hummingbird feeders up into early October, or at least two weeks after you see the last hummingbird – migrants may still be coming through.

And if you see a hummer riding on the back of a Canada goose, call me. I have a good optician to recommend for you.

Loon Study on Turtle Flambeau Flowage

            In the most recent Journal of the Wisconsin Society of Ornithology, “The Passenger Pigeon,” local researchers Jeff Wilson, Terry Daulton, and Bruce Bacon published the results of their 2012 study of loon nests on the Turtle Flambeau Flowage (TFF). The TFF contains over 150 islands and has around 175 miles of shoreline, only 5% of which is developed. Annually, the TFF supports from 22 to 32 nesting loon pairs, in addition to many non-breeding loons who interact with the breeding pairs.

The researchers wanted to identify and quantify the causes of nest failures in loons. So they placed digital infrared motion detection cameras above 21 nests to determine what, if anything, was causing nest losses. Prior to this study, raccoons have largely been blamed, as have mink and otters, as well as gulls, crows, eagles, and disturbances by people. But no study had actual proof of who were the culprits, and this study’s use of cameras was hoped to be one way to offer some incontrovertible truth.

            The cameras were placed on a ten-foot high pole above the nests and pointed directly down at the nests for the entire 28-day incubation period. All were set to take 1 picture every 30 seconds whenever movement at the nest trigged the shutter. Date, time, and temperature were all imprinted onto each image.

            On the 21 camera monitored nests, 7 successfully hatched eggs (33%), 4 were washed out by wave action and high water (19%), and 3 (14%)were destroyed by predators. Two of the predators were clearly raccoons and the third was a mink.

            Of the other 7 nests, two were suspected of predation but the camera failed to capture the culprit. Three nests were abandoned. At one nest, the adult loon accidently rolled its egg into the water after one egg had been removed by an unknown predator the previous night. And the final nest had infertile eggs.

            An additional 18 nests were monitored visually via binoculars/scope. Five of those successfully hatched eggs (28%), 5 were washed out, 4 had unknown failures, 2 were destroyed by unknown predators, 1 was infertile, and one failed due to people camping too close to the nest.

            Combined, the 39 nests surveyed had 12 successful hatches, a 31% success rate, while 9 were washed out (23%), and 6 were destroyed by predators (15%).

            This rather low success rate is not cause for great concern given that loons are long-lived, often to 20 years or more, and thus don’t need high annual replacement rates.

            Interestingly, northern populations of common loons did not evolve with raccoons, which are only a relatively recent addition to the Northwoods following land clearing and development. Raccoons were actually stocked in northern Wisconsin in the 1940s from the Poynette Game Farm.

            Loon productivity varies dynamically from year to year. In 2011, over 50% of first nest attempts by loons in Vilas, Oneida, Forest, Langlade, Price, and Iron counties were lost due to nest abandonment caused by swarms of black flies. Second nest attempts, however, proved mostly successful, and productivity was deemed adequate.

            In 2012, no nests were abandoned due to black flies. Instead, nest flooding and predation were the principle known causes. That spring was unusual in how early the ice went off our lakes. On the TFF, which is controlled by a dam, the Flowage wasn’t completely refilled until around June 1. Given that the first loon nest was initiated on May 8, that meant that water levels kept rising for another 3 weeks, in many instances flooding out the nests, which on average are only built 6 inches above the water surface.

The research cameras recorded wave action washing out nests as the water rose, as well as loons unsuccessfully adding nesting material to try to raise their nests above the water.

            One management recommendation arising from the research is for water stabilization on flowages to occur by May 1 so loons have a fair chance at placing their nests at the right height above the water. It may be that stable water levels are every bit as important as other factors in loon nesting success.

Sightings – Coming Soon

Nighthawks have begun their migration. Look for flocks of them in the early evening darting around in the air, mouths wide open, in search of insects. Peak migration occurs in late August as they follow the last hatches of insects south.

Powell Marsh Master Plan

The DNR is resuming the master plan process for the approximately 4,800-acre Powell Marsh Wildlife Area in Vilas County. The wildlife area lies three miles south of Manitowish Waters, and is bounded by the NHAL State Forest and by the Lac du Flambeau Indian Reservation on the south. A public information meeting will be held on August 24 from 2-5 p.m. at the Manitowish Waters Community Center, with a short presentation at 3 p.m.

The updated planning documents, including maps of the property, can be viewed by searching for “master planning” on the DNR website – dnr.wi.gov – and clicking on “Powell Marsh Wildlife Area.” The planning materials area also available at the DNR Woodruff Service Center, or by contacting Michele Woodford at 715-356-5211, ext. 207, or email: Michele.Woodford@Wisconsin.gov.

Currently, Powell Marsh Wildlife Area is mostly an open peatland with several small flowages and small lakes. It encompasses a portion of a 20,000 acre wetland complex mostly owned and managed by the Lac du Flambeau Band of Lake Superior Chippewa.

Roadside “Weeds”

August brings a lovely array of roadside wildflowers into being, though many of them are not native to North America. Some of these aliens are not invasive, and thus not of concern – butter and eggs, for instance, or goat’s-beard, mullein, common St. John’s-wort (though some say this is invasive), and tall buttercup.

Other non-natives are invasive, however, and need to be removed. The list is long, but the ones that I think are of most concern, at least of the upland flowers, are spotted knapweed, tansy, bird’s-foot trefoil, most thistles, curly dock, common burdock, and orange hawkweed. Garlic mustard is the one I fear the most – if you haven’t seen what it’s done in southern Wisconsin, you have no idea how extraordinarily invasive this species can be.

Some roadside species that one might think to be non-natives turn out to be natives, like stinging nettle, goldenrods, ragweed, fireweed, and common yarrow.

            Thoreau had an interesting take on “weeds,” writing: “I sympathize with weeds perhaps more than with the crop they choke. They express so much vigor. They are the truer crop which the earth willingly bears.”

Others simply say that weeds are plants that out of place.

            Regardless, enjoy the roadside displays – our first hard frost may not be that far away.

Celestial Events

            As of 8/28, we’re down to 13.5 hours of daylight. By 9/6, we’ll be at 13 hours, well on our way to equal day and night on 9/22, the autumn equinox.

On 8/31, look before dawn for Jupiter about 4 degrees north of the waning crescent moon.

For planet watching in September, brilliant Venus is very low in the southwest at dusk, as is Saturn. Before dawn, look for both Mars and Jupiter in the east.

NWA 7/26/13

A Northwoods Almanac for July 26 – August 8, 2013       

Snapping Turtle Kills and Eats Porcupine

Elaine and Dana Hilmer witnessed an event on July 8 that I think is quite unique – a snapping turtle capturing a porcupine by the foot, pulling it under the water, drowning it, and then eating it. Here’s their description:

“We left about 9:30 am from Murray's landing and paddled up into the big bay to the north. At noon, I noticed a young porcupine feeding along the shore in a little bay that had some dead tree trunks that had drifted up against the shore. We started taking pictures and movies of the porcupine. The porcupine moved out on some of the logs and started browsing on some of the water plants. Then we noticed that something was bothering his foot. He started thrashing around and we thought he fell off the log, or that he was feeding on something in the water. After a few minutes there was a little movement from him but something did not look right. He did not come up for air.

“Then we saw the large turtle head, and we started to put the pieces of what we saw together. What we had just witnessed and recorded video of was a large snapping turtle drowning a porcupine to eat!

“We were recording this from about 20 to 50 feet away and being quiet so we did not spook the porcupine. Now we know that if we had spooked him, we could possibly have saved his life.

“Once we guessed that he was dead, I moved in to about 2-3 feet away, and that is when I got a good look at the turtle that was feeding on the drowned porcupine. I could see the quills from the porcupine that were stuck into the turtles neck, arm and hand from the struggle.”

            Elaine and Dana provided us with a 9-minute-long video of the event, proof positive of the event occurring. Strangely, the porcupine uttered almost no sound during its death struggle.

            As Elaine and Dana described, the snapping turtle had numerous quills stuck in its face and feet. A porcupine’s quills are barbed like a fishhook and will work their way deeper and deeper into an animal’s skin, eventually coming out the other side of a leg or an arm. But what happens with quills in an animal’s face?

            Snappers are known to pull ducklings under water and consume them, but I’ve never heard of a snapper taking a porcupine.

            For that matter, most folks have never heard of a porcupine eating aquatic plants, but indeed they do. Like beavers, porkies consume the inner cambium layer of tree bark. But in the summer, if succulent green plants are available, both beavers and porkies will readily consume living plants rather than bark.

Snappers also eat aquatic plants. In fact, plant matter accounts for about a third of their diet. But as aggressive, ambushing omnivores, snappers feed on just about anything that moves, including insects, spiders, worms, fish, frogs, small turtles, snakes, birds, crayfish, small mammals, and carrion.

Please never pick up a snapper. Lifting a snapper with the hands is truly dangerous given that snappers can stretch their necks back across their own carapace all the way to their hind feet to bite. Also, their claws are large, sharp, and will lacerate you. And then there’s the beak, which is nothing to mess with either.

So, appreciate snappers, but give them a little distance. Though they are powerful predators, they are absolutely remarkable beings that have been a native component of our lake and river communities for many thousands of years.

Surveyor Journals

Mary and I recently led a paddle trip on Pallette Lake and Escanaba Lakes, two lakes that were part of a documented fur trade route during the early 1800s. If a French voyageur or Native American wanted to get from the Ojibwe village at Lac du Flambeau to the village at Lac Vieux Desert, he would leave in his canoe from Lac du Flambeau via Flambeau Lake into Pokegama Lake, then paddle and portage into White Sand Lake, into Ike Walton Lake, into Trout Lake, into Pallette Lake, into Escanaba lake, into White Birch Lake, into Ballard Lake, into Irving Lake, into Laura Lake, into Upper Buckatabon Lake, and finally into the Wisconsin River.

What’s interesting is to try and find the original trails between the lakes, most of which are long gone. One way to determine where the trails once were is to access the original surveyor records from the 1860s. When the surveyors crossed a trail, they usually indicated in their journal exactly where that point occurred. So, in September of 1864 for the portage between Ike Walton and Trout Lakes, the surveyor, John McBride wrote as he walked north between Sections 15 and 16, “Trail bears E and W” at 73 chains. One chain equals 66 feet, so he was 4,818 feet from the south corner between the two sections, or 462 feet (5280’ - 4818’) from the north corner between the sections. He also noted that he crossed the same or another trail at 74.5 chains, another 99 feet north of his first encounter with the first trail, and that this trail “bears NW and SE.”

With modern GPS units, one can find section corners rather easily. Then it’s just a matter of setting the GPS to go the distance and direction you want, and hopefully stumbling upon an ancient trail.

The BCPL surveyor notes are all available at: http://bcpl.state.wi.us/, then click on “Online Records.”

Sightings

7/13: Mary and I hiked a trail in Price County after a rain, and with the intense humidity and heat of that week, the mosquitoes were absolutely bedeviling us. However, once the trail opened up a bit, it was the deerflys’ turn. To take care of them, I placed one of my handy-dandy, very sticky “Tred-Not” deerfly patches on my cap, and within a half hour, I’d caught 80 deerflies on my patch, a fine harvest indeed!

There’s no better way to beat the deerflies. Many sporting stores carry the patches, but if you can’t find them, go to: www.deerflypatches.com  

7/14: We paddled Nixon Lake (southeast of Boulder Junction) and were delighted to see a pair of trumpeter swans with three cygnets. Nixon had been the site of nesting trumpeters a decade or more ago, and we weren’t aware the swans were again nesting there.

7/20: Mary and I took a stroll in a bog in Presque Isle and found dozens of grass pink (Calopogon tuberosus) orchids still in bloom, as well as dozens of pitcher plants.

7/20: The Juneberries in our yard are coming ripe, and the cedar waxwings are making short order of them.

7/21: We ate our first ripe blueberries while on a hike on the Kentuck-Spectacle Lake trail, a trail that we highly recommend taking. A black-and-white warbler chick flew right at us when I “pished” for birds on the trail. Young-of-the-year songbirds are fed by their parents for several weeks after fledging, so perhaps this one thought I was a source of food. Or it may just have been curious in general, a potentially bad trait for a young bird needing to survive.

7/21: We stopped at a site along the Luna-White Deer trail where in the past we have seen hundreds of horned bladderworts (Utricularia cornuta) in flower, and they were still there. Horned bladderworts are a rooted bladderwort along wet shorelines – other bladderworts are mostly free floating in shallow water – and like their brethren, they are carnivorous. The flowers, however, have a wonderful smell. John Burroughs, a famous American naturalist and writer in the late 1800s-early 1900s, believed the horned bladderwort to be the most fragrant wildflower of all flowers he had ever encountered, a very tall compliment indeed.

7/22: We’ve seen numerous hazelnut bushes loaded with hazelnuts, so it appears to be a banner year for them.

Celestial Events

            We’re down to 15 hours of daylight as of today, 7/26, and losing three minutes of daylight every day, a depressing thought indeed to those who love thesse long evenings of light.

            The peak Delta Aquarid meteor shower, rated at 15 to 25 meteors per hour, takes place in the early morning and evening hours of 7/28. If you trace all the Delta Aquarid meteors backward, they appear to radiate from in front of the constellation Aquarius the Water Bearer, which, arcs across our southern sky.

            On 8/3, look before dawn for Jupiter four degrees north of the waning crescent moon. On 8/4, Mars nearly takes Jupiter’s place about five degrees north of the waning crescent moon.

            As of 8/5, we’re midway between the average ice-out and ice-up dates on many of our northern lakes.

             The new moon occurs on 8/6.

NWA 8/9/13

A Northwoods Almanac for 8/9 - 22, 2013  

Enormous Decline of Monarchs

Many people have commented to me this summer that they’re not seeing monarch butterflies at all. At first, I thought it might be due to our inordinately delayed spring, but there’s a much bigger story going on. Last winter, scientists surveying monarch habitat in Mexico's Monarch Butterfly Biosphere Reserve found the insects occupied 59 percent less land than the previous year—the smallest area ever recorded. Nine butterfly colonies were found in just 2.94 acres of land, compared with 7.14 acres in 2011 and a high of 44.9 acres in 1997.

It's normal for the monarch population to vary from year to year – a storm in January 2002 killed 80 percent of those overwintering in Mexico, but the population was near normal a little more than a year later. However, this year's steep decline is being blamed on two main causes: extreme climate fluctuations, including long-term drought, plus heavy spring rains and cold this year, and widespread loss of milkweed, which the monarch caterpillars rely almost entirely on for food.

The monarch doesn't fare well in extreme weather, and last summer's Midwest drought was the worst in 25 years. March 2012 was the warmest recorded since nationwide record keeping began in 1895. The first generation monarchs moving north-northeast out of Texas arrived much earlier in the northern breeding areas than previously recorded. These early establishments were followed by one of the hottest and driest summers in recent decades. Hot and dry conditions are believed to have the effect of reducing adult lifespan, and therefore the number of eggs laid per female over their lifetime. Plus temperatures above 95˚F can be lethal for larvae. Six of the last seven years have shown drops in monarch populations, and there are now only one-fifteenth as many monarch butterflies as there were in 1997.

It’s not just about conditions too hot and too dry. Monarch eggs, larvae, and pupae develop more quickly in milder conditions, thus the long cold and wet spring this year also meant that monarchs have been slower to reproduce and migrate.

Another factor in the decline is the use of pesticides to treat weeds in the American Midwest. The Midwest is a key habitat for monarchs because of milkweed, which thrives along the borders of its corn and soy fields. When farms began to use the herbicide Roundup on genetically modified corn and soy in the early 2000s, milkweed disappeared, and with it, the monarchs that use it to feed and reproduce. The herbicide-resistant crops can withstand the chemical spraying, but the milkweed can’t.

The push for the production of biofuels has contributed to the loss of milkweed, too. Over 25 million more acres of corn and soybeans have been planted since 2006 at the expense of Conservation Reserve Program lands which supported high numbers of milkweed plants. The recent high prices for corn have also created more intensive farming, which has reduced the area from the edge of roads to the farm fields. Towns and counties also are now increasingly using herbicides for management of roadside weeds, which also eliminates milkweeds.

Logging was once considered the main threat to the winter reserve area, located west of Mexico City. At its peak in 2005, logging devastated as many as 1,140 acres annually in the oyamel fir forests reserve, which covers 193,000 acres. But a 2012 aerial survey showed almost no detectable logging, the first time that logging had not been found in detectable amounts since the mountaintop forests were declared a nature reserve in 2000.

The problems associated with extreme weather and genetically modified crops are far larger than crashing monarch populations. Vera Krischik, a University of Minnesota entomology professor, believes that honeybees, bumblebees, parasitic wasps and many other kinds of beneficial, pollinating insects — including other butterflies — are also noticeably absent this year.

A Hundred Billion Planets in the Milky Way

            Mary and I led several hikes for Nicolet College last week, and one of the participants on the hikes was Dan Schroeder, a retired astronomer who worked on the building of the Hubble telescope. Dan and his wife LaVerne have hiked with us many times over the years, and we always try to ask Dan what the latest news is in the world of astronomy. And this time, the word was “Planets,” and lots of them.

            Dan recalled back in 1996 when an announcement was made that two planets had been discovered orbiting a sunlike star. The observation shook the world of astronomy, because no one had been looking for planets under the assumption that they would be too hard to find. Now, astronomers had reason to look, and they launched an effort to search for “atmospheric biosignatures” that would provide further evidence of extrasolar planets.

Some planets were additionally discovered in the intervening years, but it took the launching of the Kepler space telescope on March 2009 to change everything. With the mission to discover Earth-like planets in our galaxy, the Kepler was designed to continually monitor stars in just one small fixed area of the sky to see if it could detect periodic dimming caused by planets crossing in front of their host star. Kepler's field of view covers around 0.28 percent of the sky, or "about two scoops of the Big Dipper." Thus, it would require around 400 Kepler-like telescopes to cover the whole sky.

In the last three years, NASA’s Kepler telescope has found enough evidence of planets that astronomers at the Harvard-Smithsonian Center for Astrophysics estimate that “at least 17 billion” Earth-sized planets reside in the Milky Way Galaxy. And they now believe that on average, every star should have at least one planet. Given that our galaxy alone has at least 100 billion stars, it must also have at least 100 billion planets that are orbiting the stars.

            The BIG question, of course, is whether any of those planets can sustain life. In March 2011, astronomers at NASA reported that about "1.4 to 2.7 percent" of all sunlike stars are expected to have earthlike planets "within the habitable zones of their stars." However, there is no specific data that currently enables astronomers to answer the question of life on other planets. Nevertheless, since there are more than 100 billion galaxies in our observable universe, and small planets have been discovered to be extremely common, odds are that other life must exist somewhere out there. See the August 2013 issue of “Sky and Telescope” for a detailed article on the latest research.

Sightings – Spruce Grouse, Greater Yellowlegs, and Albino Squirrels

From Jim Cheshire in McNaughton: “While returning from work on July 13th at about 7:45 pm, I could see a small, gray animal several hundred yards ahead in the middle to the road. As I got closer, I assumed it was a ruffed grouse dusting itself in the road. However, when I got within about 50 yards, I realized this was a different type of bird (a rare spruce grouse). So, I pulled my car over and began walking toward the bird with a camera. Near the shoulder of the gravel road I noticed about 6 tiny chicks that I hadn’t seen yet. Since they were only slightly bigger than a computer mouse, I assumed the chicks could not fly. So, I tried to line them up in the foreground with the hen spruce grouse in the background. However, the chicks quickly flew into the swamp before I could take a picture. I later learned on the internet they can fly within 6 to 8 days of hatching (which must be a great defense mechanism). The hen spruce grouse allowed me to walk to within about 25 feet before getting up and nervously walking away. I got a pretty good photograph of her in the road and another when she flew up into a nearby pine tree. I then quickly left so that the hen could reunite with her chicks.

             “Much of what the Wisconsin DNR describes as suitable spruce grouse habitat perfectly matches much of the land in this area. There are thousands of acres of black spruce, tamarack, and jack pine that spruce grouse are known to prefer. So, since there was obviously a breeding pair, I suspect there is a self-sustaining population in the area.”

            On a different note, bird migration has already begun. Warblers are starting to move south, and shorebirds have been coming through Wisconsin since late July. Mary and I observed a flock of a dozen greater yellowlegs, a shorebird that breeds in muskeg habitats of central Canada and southern Alaska, on Powell Marsh on 8/5. Yellowlegs winter in numerous countries in South America – adult birds often reach Argentina by late August.

            Nancy Eckman in Minocqua sent me photos of two albino gray squirrels that frequent her feeders.

Celestial Events

            The Perseid meteor shower peaks during pre-dawn hours on 8/12. The Perseids are rated at an average of 60 meteors per hour, or one per minute, but at their heaviest, about 90 meteors an hour are predicted.

Light conditions should be good given that the Moon reaches its new phase on 8/6, and thus will be a waxing crescent around the anticipated peak for the Perseid meteors.

The source of the Perseids is comet Swift-Tuttle, discovered in 1862 by astronomers Lewis Swift and Horace Tuttle. Swift-Tuttle is on a 133.3-year orbit, and last passed through the inner solar system in late 1992.

The Perseid meteors are not a one-night show. For several days before and after the Aug. 12 peak, you can likely catch the shooting stars.

Besides looking for meteors, don’t forget to search for planets. Look for Venus and Saturn in the west-southwestern sky at dusk. Of the two planets, Venus is brighter at negative 3.9 magnitude. On 8/9, a very skinny crescent moon cruises the sky with Venus, while on the evening of 8/12, the moon will be to Saturn’s lower right. The next night, the moon will be to Saturn’s lower left.

Look for the full moon on 8/20.