Tuesday, July 9, 2013

NWA 7/12/13


A Northwoods Almanac for 7/12 – 25/13      by John Bates

Sightings
            Eagle and osprey chicks are on the verge of fledging. The chicks of both species usually are airborne by August 1 at the latest.
            The warm water of July brings on the prolific flowering of aquatic plants. One of our favorites, marsh milkweed, was just starting to come into bloom on July 6. A monarch butterfly was already visiting one of the blooms, perhaps already laying its eggs.
            Scott and Kathy Reinhard sent me this note: “Kathy and I enjoyed your article on the white pelicans and found it ironic that it ends with a prediction of them nesting on the Turtle Flambeau Flowage. On June 24 we saw a flock of six white pelicans flying on the southern end of the TFF near Beaver Creek! That's a first for us.”
On July 1, Kathy Esche, who lives a few miles north of where Highways B and M intersect near Presque Isle, sent this email: “When I was out walking this early AM, I saw a moose! He had a huge rack and was a dark chocolate brown color. He was on the edge of the road but started running when my springer started down the road towards him. He ran about 30 or 40 feet and then went into the woods, so I got a good look at him . . .
I’m from CT and have seen moose in Maine, so it was exciting to see one in my new home town.”
I received beautiful photographs of luna moths from Denice Schroeder on the Pike Lake Chain and Kay Streng on Diamond Lake, as well as a photo from Denice of a blinded sphinx moth, a species I was unfamiliar with. Denice wrote about the luna moth: “At first glance I thought it was some sort of bright lime to mint green leaf, and I couldn't figure out why it was on the side of the hemlock trunk. Its wings were closed and stayed that way for quite some time. We were determined to keep an eye on it until it opened its wings. The wait was worth it. An absolutely gorgeous moth unfolded.” 
            We recently saw black terns on the Turtle-Flambeau Flowage and Big Musky Lake. It’s a treat to see them because of their remarkably buoyant flight, but also because they’re quite uncommon. Black terns are listed as a “species of special concern” in Wisconsin, a category meaning there’s a strong suspicion of a problem with the species’ abundance or distribution. The category’s main purpose is to focus attention on a species before it becomes threatened or endangered.
Mary, Callie, and I paddled on Nixon Lake last week, and were really pleased to see a pair of adult trumpeter swans with three cygnets. Nixon was a site for nesting trumpeters in years past, but I wasn’t aware they had begun nesting there again. The lake is very shallow, perhaps seven feet at its deepest, and thus rich in aquatic plants – the lake surface is as much floating leaves as it is water. So, the paddling was slow, but the rewards came from the associated bird, insect, and amphibian life.
            Over the weekend, Mary and I paddled the Manitowish River down into the Turtle Flambeau Flowage, and we noted how high and how stained the water is this year. The root beer color likely derives from the continued high water flushing the wetlands along the river which have been mostly dry over the last drought-ridden decade. We have had standing water in the wetland below our house all summer so far, and the Turtle-Flambeau is at full pool. So, water levels are up this year, though many seepage lakes still have a long recovery ahead of them to reach their normal high water marks.
            The four most common birds we saw and heard in all of our recent paddles were common yellowthroat warblers, song sparrows, eastern kingbirds, and cedar waxwings. Most people associate cedar waxwings with eating fruits and berries in upland areas, but in the summer, they are avid flycatchers over water, using the protein to raise their chicks.
            We also were a bit surprised by the lack of ducks on the rivers and lakes. But we shouldn’t have been. This is the time of year when emergent vegetation along the shorelines provides needed cover for mother ducks and their chicks. They don’t want to be seen, and this year our abundant shoreline vegetation is optimal for their protection.
At one point I did surprise a hen wood duck with her brood, and she proceeded to do an unable-to-fly distraction display to draw me away from her chicks that would have won her an Academy Award. Had I not known what she had up her sleeve, it would have worked, but I just looked in the opposite direction to find where the chicks were hidden.

Mink Eating Northern Water Snake
            Bob Orgeman in Rhinelander sent me several photographs he captured of a mink preying upon a northern water snake, and added this note: “I watched this mink running up and down on a dock all the while looking into the water. It finally jumped in the water, emerging shortly with this snake, which it killed with a bite to the head.”
            Mink are exceptional predators, but I’m not sure I would have believed they could capture a 3-to-4-foot-long water snake! Northern water snakes are the Northwoods’ only true water-based snake, and while non-venomous, they are formidable predators of crayfish, amphibians, and slow moving fish. Mary and I often see them basking on beaver lodges where they perfectly blend into the piled sticks and mud. If seen swimming near a shoreline, they can clear a bunch of wading people out in a hurry, even though they have no interest in humans whatsoever.
            Back to the mink: as a member of the weasel family, they are consummate predators, but weighing only 2 to 4 pounds themselves (the smaller females only weigh between 1.5 and 2.5 pounds), you wouldn’t think they were big enough to tackle anything as large as a northern water snake. But so they can, as well as an array of other prey like fish, frogs, crayfish, birds, rabbits, muskrats, and various rodents.
           
Bank Swallow Colonies
            As one paddles the Manitowish River closer to the Turtle-Flambeau, some high, steep sand banks appear along the river, and here last week Mary and I came across two separate colonies of bank swallows having what we hoped was a glorious time eating the empire of mosquitoes that were encamped along the shorelines.
            We rarely see bank swallows, so this was a treat. These gregarious birds not only nest together in colonies, they forage together, darting over rivers and lakes in erratic aerial maneuvers to capture flying insects which comprise 99% of their diet.
            Bank swallow colonies vary from a few pairs to 100 or more, but given that their nest sites tend to erode or cave in frequently, their appearance in an area is often short-lived. They dig their burrows two to three feet into the banks, and sometimes as far as five feet, excavating a nesting chamber at the end that is 5 or 6 inches across.
            This is a species that has likely benefitted from human development, because they are as willing to nest in the vertical walls of a gravel pit or excavation site as they are in a high river bank. In fact, during the lumbering era, bank swallows were observed colonizing large sawdust piles around the sawmills.
            The limiting factor for their nesting is cave-ins. They need stable banks with the right consistency of soil – just the right mix of sand and clay.
            They’re noisy birds, chittering constantly, but it was a welcome lively racket along an otherwise very quiet river.

Reed Canary Grass
            The one major disappointment in our recent paddles? The incredible takeover of shoreline vegetation by reed canary grass. This invasive species has flown under the radar of most of us, and we need to start focusing on it. It does stabilize bank soils, so provides a good service in that respect. But otherwise, it’s an occupying army that quickly becomes a monotype along our shorelines.

Wild Roses
            Wild roses are wildly in bloom along many of our shorelines and wetlands. What a beautiful flower and such a glorious smell!

Fireflies
            Speaking of things that are somehow beyond words, the flickering glow of fireflies occurs every night now below our house. It’s otherworldly – a bug that lights up, flashing in an orderly pattern like a little Christmas bulb to attract a mate. Fireflies contain luciferin, a chemical that, when it combines with oxygen and with an enzyme called luciferase, causes their abdomen to light up. This bioluminescence creates a light that is utterly efficient, producing no waste heat – just light and beauty. Check out this website for some incredible long-exposure photographs of fireflies: www.boredpanda.com/long-exposure-fireflies-yume-cyan 

Low Bird Populations
A number of people have commented to me that there were fewer birds in the woods this year, and I have to agree. We just didn’t hear, nor see, the volume of birds we typically experience on any given walk or paddle. The reason appears to be this year’s exceptionally cold spring. Songbirds that winter in the tropics time their return to coincide with the emergence of insects that occurs when trees are leafing out. This year’s very late leaf-out created a shortage of insects for many migrants that arrived at their usual time.
An example of this occurred on May 19 on Park Point in Duluth, a stopover site for migrating birds. A huge “fallout” of migrants occurred at Park Point on this day. They were “on time” – mid-May is when they invariably appear – but for four straight days 
strong Northeast winds, rain, and fog  grounded the birds. The birds couldn’t continue north in those conditions, so had to wait it out. But there was almost nothing to eat. Local birders were able to observe hundreds of warblers feeding mostly on the ground, giving unparalleled views of 25 species at close range, often within just a few feet. While the viewing was phenomenal, the birds were exhausted and hungry, and many of them succumbed to hypothermia and starvation. The weakened birds were also easy targets for predators, who also took their toll.
So, when the woods should have been alive with bird song in late May and early June, it was relatively quiet as the need to defend territories by singing wasn’t as urgent as normal. We even thought the robins around our house were abnormally quiet. Without real data, this is more my sense of things than scientific evidence, but I think there’s some truth to it.

For planet viewing in July, Venus remains visible low in the western horizon at sunset, setting a little over an hour after sunset by the end of the month. Saturn
remains visible low in the southwest throughout the month.
On July 22, look for the full moon. This moon has three nicknames: The Buck Moon, because this is the month when the antlers become more visible on male deer. The Thunder Moon due to the frequency of thunderstorms during July. And the Hay Moon, because in farming regions, haying begins this month. That same morning, look low in the northeast for Mars less than one degree north of Jupiter. 

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