A Northwoods Almanac for August 5 – 18, 2011
Black Flies and Loons
In an average year, over 50% of nest attempts by loons fail, but since loons will nest up to three times in a given year, they are often successful in subsequent attempts. Nest predation is usually the leading cause of nest failure, with raccoons leading the pack as the most common predator. But other species also predate on the eggs, including red fox, mink, raven, and bald eagles. Other causes of nest failure include 1) flooding of nests due to water level changes or wave action, 2) abandonment due to black flies, 3) repeated human disturbance resulting in nest abandonment, and 4) failure of eggs to hatch.
This spring, however, nest failure reached what may be an all-time high due mostly to a huge black fly hatch. In particular, one black fly species, Simulium annulus, feeds primarily on the blood of common loons. During warm springs, black fly swarms peak in mid to late May in northern Wisconsin, coinciding with the peak of loon nest initiation, and often cause nest abandonment. This spring, a much higher percentage of loons’ first nest attempts failed throughout our area, with black flies serving as the major cause of failure. The precise numbers on this, however, are still being calculated and won’t by available until late September.
The good news is that most of the loons re-nested, and by that time the black flies had subsided enough that most of those nests were successful. Getting the eggs to hatch is the key in loon reproduction because once chicks hatch approximately 85% survive to fly off the nest lake in the fall.
Wild loons can live 20-25 years, thus they also have numerous nesting seasons to attempt to produce young. So, one bad spring is not cause for great alarm, but nevertheless is worrisome.
Sightings
Dragonflies: Beth Huizenga took an excellent picture of a female calico pennant dragonfly in early July at the Wolter wilderness area. She felt it was one of the prettier dragonflies she has seen, and I’d agree. A few days before Beth sent us her photo, Mary and I had paddled on Camp Lake and had seen many dozens of these small dragonflies alighting on emergent vegetation along the shoreline. The males’ scarlet
abdominal spots make them very distinctive, while the female differs by having yellow abdominal spots.
Albino Crows and Squirrels:
Linda Thomas reported that there are two white (presumably albino) crows on the Plum Lake golf course, apparently the young of two black crows that are seen with them.
I also received two reports of albino squirrels, one from Ron Morrell and another from Mara Coon. Mara sent a photo of the one she had seen on Broken Bow Lake.
So how rare is albinism? Over 300 species of North American birds and animals, from whales to snails, have been recorded as having some form of albinism or its many variants. In humans, about one in 20,000 people have one type or another of albinism. Mammalogists estimate that one in 10,000 wild mammal births results in a true albino. In birds, one study of 30,000 wild birds captured in mist nets in Southern California found only 17 displaying some degree of albinism, or one in 1,764 birds.
Triplet Loon Chicks:
Suzy Foster sent me a photo of triplet common loon chicks on McCullough Lake. Triplets are very rare – one to two chicks are the absolute norm.
Bobcat: Jim Schumaker sent me an exceptional photo of a bobcat walking through their back yard near Sayner several weeks ago. Bobcats are usually secretive and seldom seen – this one clearly hadn’t heard about this expectation.
Kingbird Dilemma and Fix
Eastern kingbirds often nest right along shorelines, and are known to use boat lifts and docks as nesting sites. Their choice of these nest sites can be a major problem given that kingbirds are “kings” of their nesting territory and do not tolerate intrusions, human or otherwise.
So, here’s how to handle this dilemma as experienced by Dave Eitel near Minocqua: “On June 29, a pair of kingbirds had built a nest in one of the cup holders on the pontoon boat and there were three chicks in it. Big problem. If we used the boat the birds wouldn't get fed, and not using the boat was out of the question.
“The solution: move the nest. I rigged up a plastic milk case with a heavy brick in it so it wouldn't blow away, and set that on a bench on the pier near the boat. I then used a beach umbrella to disguise my dastardly deed from the birds and snatched the nest from the boat and put it on the pier about 8 feet from the original next location. The birds couldn't find it (just kept flying to the spot where it had been), so I moved the crate back to the boat about 2 feet from the original location. After about an hour the birds finally found it and started feeding the chicks again. A couple of hours later I moved the crate to the pier and they found it after about a half hour.
“The next morning I moved the nest in its crate on the bench 20 feet or so at a time, ultimately placing it on top of the boathouse where there is plenty of open space and lots of perching areas and the kingbirds are feeding away. It was amazing how long it took them to go back to the nest each time it was moved, but it got shorter after a while. One final move to the farthest corner of the roof and the birds are happy and we're happy. About 11 days later the chicks had flown the nest and were sitting nearby in the trees as the adults continued to feed them.”
Red-necked Grebe
Pat Schwai sent me a photo of a red-necked grebe swimming near the shoreline and over a projecting snag. She noted: “Occasionally it dove but remained in the same area even when we approached it to take photos. As dusk was falling we became concerned that it might be tangled in fishing line. Fortunately it was free and had left the area by morning (7/22).”
She asked that I not reveal the site because of the rarity of the bird. And indeed seeing a red-necked grebe in our area is a rarity. Because they are at the edge of their geographic range in Wisconsin, they are listed as a state endangered species. They typically breed in more northern and western areas from Alaska to Thunder Bay, Ontario. I’ve never seen one here, though I have seen numbers of them in migration on Lake Superior at Whitefish Point Bird Observatory near Paradise, Michigan. Their rusty red throat is absolutely beautiful.
Northern Water Snakes
Several weeks ago, Mary and led a paddle trip on the Trout River, and we stopped at a beaver dam to look for basking northern water snakes. We hit the jackpot and observed eight of them, all of which acted quite unperturbed by our excited peering. Our only true water snake in northern Wisconsin, these two to three foot-long, non-venomous snakes blend in very well with the beavers’ wooden dams given their brown and tan coloration. They mostly eat frogs, crayfish, minnows, and slow-moving small fish, so pose no significant ecological problems, and instead often make a positive impact on a fishing lake by thinning our stunted fish.
Deer flies and more deer flies and more . . .
So, how ‘bout them deer flies this summer! Yikes. Between the mosquitoes and the deer and horse flies, it’s been a tough summer to be in the woods. I like to use the commercially made sticky patches on the back of my hat to catch deer flies, and on one recent hike, I captured 42 of the little beasties in less than an hour. A participant on the hike had another 32 on his patch, so between us we had 74 deer flies (see www.deerflypatches.com to order). More importantly, the circling deerfly Indianapolis 500 racetrack that was going on around our heads came to a very thankful close.
It’s the bloodthirsty females that exact the pain. Unlike mosquitoes, deer flies and horse flies are “stealth” fliers that circle their target before landing from behind and usually at the highest point, and then biting immediately. The females use their knife-like mandibles to cut through human flesh, leaving a cross-shaped incision. The good news is that compared to that of mosquitoes, the deer fly season is intense but relatively short.
Horse flies are the 747s of the family. E. Laurence Palmer, in his Fieldbook of Natural History, describes the horse fly mouthparts as “a series of cutting and piercing stylets that can penetrate the toughest hide.” Their bites often bleed, because the female’s saliva contains an anti-coagulant. The black horse fly can be 1¼ inches long but looks and feels much bigger.
Horse flies and deer flies have the charming habit of pursuing cars and bicycles. My bicycle solution is to tie a helium balloon to the back of your bike. Since deer flies and horse flies like to fly around the highest thing, let them spend their time biting your balloon. Better yet, put some sticky solution like Tanglefoot on the balloon, and you’ll trap dozens.
Celestial Events
August 6th marks the average midpoint between ice-out and ice-up on our area lakes, while August 7th marks the midway between summer solstice and autumn equinox.
The Perseid meteor shower peaks on 8/13, but you can begin looking for it as early as August 8th. Unfortunately, the full moon occurs on the 13th as well and will illuminate the sky too much for prime viewing.
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