A Northwoods Almanac for May 6 – 19, 2011
Blowing in the Wind: Counting Hawks on Brockway Mountain
Last weekend, Mary and I traveled to the Keewenaw Peninsula to scout a hawk-watch trip for Nicolet College. We encountered just a wee bit of wind on April 30 up on Brockway Mountain where the official hawk count takes place. Here’s Arthur Green’s (the official hired counter) blog post for the day: “A bleak sky? For sure! Today, we spent the day shielding our eyes from the wind-blown particles of eroded conglomerate blown off the ridge face by nearly constant 35+ mph southeasterly winds. My usually sturdy scope tripod was blown to the ground with ease, and it seemed as if I was routinely chasing down an article of clothing or making sure my clipboard wasn’t blown off the mountain. Even after a shower, I’m still finding bitsies of stone in my hair.
“Birds particularly reliant on soaring flight were conspicuously absent in number today . . . However, Sharp-shinned Hawk and other powered-fliers (including Peregrine Falcon) were out in force. As cloud cover thickened and progressively invaded the sky, we were treated to a nearly constant movement of birds within easy unassisted view of West Bluff low in the valley between Brockway and Rocky Ridge. This flight-line was probably a blessing in disguise; our binoculars were under the spell of an unyielding tremor from those winds, and not particularly useful for viewing at distance. In any case, only a few daring fliers ventured any appreciable height above the treeline, and nearly all our observations were unexpected flybys that required constant vigilance . . . This was hardly anyone’s ideal spring hawkwatching day . . . [with] conditions that left us temporarily hard of hearing and a little worn around the edges.
“The final totals for this unusual day were: 37 Turkey Vulture, 2 Osprey, 9 Bald Eagle, 7 Northern Harrier, 185 Sharp-shinned Hawk, 1 Northern Goshawk, 15 Broad-winged Hawk, 6 Red-tailed Hawk, 10 Rough-legged Hawk, 17 American Kestrel, 4 Peregrine Falcon.
“Is there a lesson to be learned in this? Yes: You’ve got to be totally nuts to be a hawk counter!”
Mary and I were really quite amazed that the numerous sharp-shinned hawks we observed were able to fly at all, much less make steady and seemingly accurate progress in a wind that we had trouble standing up in much of the time. Sharpies only weigh 5 ounces, so for them not be blown far, far over Lake Superior that day was more than impressive – it bordered on the astonishing.
Hopefully, spring will actually arrive this week, the winds will be southwesterly and moderate, and we’ll be blessed with ideal hawk-watching conditions.
We finally found our first trailing arbutus in flower on April 30th while up in the Keewenaw. Terry Daulton reported finding some in flower in the Mercer area on 4/27, but we had failed to turn any up.
Trailing arbutus is usually the first herbaceous wildflower to bloom in our sandy soils, and thus a much anticipated blessing every spring. They are not only a feast for winter-weary eyes, they also exude an absolutely lovely scent. Someone should distill this fragrance into a perfume that, with our eyes closed, we could open in March and dream spring into being.
Over the last few weeks, the evening news has reported the opening of the smelting season on the Great Lakes. I keep hoping they’ll add the caveat that smelt are an extraordinarily negative invasive species when brought into our inland lakes, and that people need to exercise great caution in moving these fish and in cleaning their nets, but there’s never a mention of this.
Most folks have a hard time understanding how such a small fish could cause the complete removal of walleye and yellow perch from our inland lakes, but it’s relatively simple. Adult smelt feed on the young of many different native species, particularly walleye, cisco, and yellow perch. Smelt also consume zooplankton, the main diet of newly hatched walleye and perch, thus limiting their development. And smelt are rich in enzymes that destroy thiamine, a vitamin necessary for the development of fish embryos. Thus, if game fish eat smelt, they can harm their own reproduction.
The bottom line – “Smelt are a death sentence. If they get into a lake, the walleye are gone in ten or fifteen years,” states Dr. Stephen Carpenter, an award-winning ecologist and professor of zoology at UW-Madison.
Case in point is Sparkling Lake north of Minocqua along Hwy. 51. Rainbow smelt were introduced into Sparkling Lake around 1981, likely from anglers washing their nets out in the lake, since smelt eggs stick to everything and nets full of spawning fish are equally full of eggs.
Smelt eat young cisco, and thus by 1990, cisco were nearly extinct in Sparkling. The smelt also dramatically affected yellow perch and walleye in Sparkling. Fall fish surveys of Sparkling Lake had shown excellent young-of-the-year walleye recruitment in the 1970's and early 1980's, but by the 1990's, the DNR found virtually no walleye young. And by 2003, they found only one individual young-of-the-year.
Sparkling's total smelt population reached an estimated 1.2 million in the 1990's, and then in a cooperative study launched by the DNR and the UW-Trout Lake Limnology Station, an effort was made to reduce the smelt. In one week in the spring of 2002, UW student researchers caught 170,000 smelt, a whopping 1.5 metric tons. In 2003, the catch fell to only 45,000, because most of the smelt spawned before the ice went out. In 2004, the researchers outsmarted the early spawners by chopping through the ice to place their fyke nets, and they hauled in nearly 90,000 smelt.
The successful management story is quite involved and greatly worth studying, but the point here is to keep smelt in the Great Lakes where their damage is apparently already done. Rainbow smelt were likely the driving force behind lake-wide collapses of cisco in Lake Superior, Michigan, and Huron during the peak of smelt abundance in those lakes in the 1940s to the 1970s.
Fifteen lakes in Vilas County, Wisconsin are now populated with smelt, and six of those lakes have already lost their reproducing walleye population. It’s further estimated that more than 500 lakes in Wisconsin are candidates for smelt invasion. If you go smelting, handle these little fish and your nets with great care – sometimes very bad things come in small packages.
Coming Soon to a Feeder Near You – Hummers, Orioles, Warblers . . .
Despite our cold spring, Baltimore orioles arrived in southern Wisconsin on April 30, as did rose-breasted grosbeaks, ruby-throated hummingbirds, and scarlet tanagers. On May 1, a birder in Cudahy recorded 23 warbler species. Thus, the neotropical migrants are on their way, crazy as it may seem given our weather.
More locally, there were even reports of hummers in Wausau on May 1, and Mark and Mary Pflieger reported a rose-breasted grosbeak at their feeders in Harshaw on May 1 despite the 33° temperatures. So, get those hummingbird feeders, those orange slices, and the rest of your bird-feeding paraphernalia out – it’s time!
Sharon Lintereur in Lake Tomahawk reports that the tapping season was short and not particularly productive. “First it was too warm, then too cold, and then just right, but by that time the trees were starting to bud, and the peepers were peeping. We ended up with 11 gallons of syrup. This is a far cry from other years.”
I still find it amazing to consider that something so incredibly sweet and delicious comes from the concentrated sap of a tree.
Ribbon Cutting Ceremony for the Van Vliet Hemlocks Trails
If you’re a hiker, or if you love old growth forests, or if you just love to celebrate positive actions by local citizens, put this on your calendar: there will be a ribbon-cutting ceremony at 10 a.m. on May 28th to celebrate the opening of numerous hiking trails on the 400+ acres of the Van Vliet Hemlocks.
Over the last year, a collaboration of community organizations including the Van Vliet Lake Association, Friends of the Van Vliet Hemlocks, The Last Wilderness Conservation Association, the North Lakeland Discovery Center, and the Wisconsin Board of Commissioners of Public Lands as well as the Wisconsin Natural Resources Foundations came together in a series of meetings to raise money and to provide the boots-on-the-ground effort to create hiking trails and signage on this natural-area quality site. It’s a special place and well deserving of the time and effort put into this project.
To see a map of the site and where the trails are, visit the Van Vliet Lake website at www.vanvlietlake.com
Yesterday, May 5th, marked the midway point between the spring equinox and the summer solstice. We’re now blessed with 14.5 hours of daylight, and we’re gaining a little over 2 minutes more of daylight every day.
Look tonight, May 6, for the peak of the Eta Aquarid meteor shower, rated at 20 to 40 meteors per hour. Best times are predawn.
On 5/8, look low in the northeast before dawn for Mercury just one degree south of Venus. On 5/10, Mercury will be 2 degrees south of Jupiter at dawn, while on 5/11, Mercury, Venus, and Jupiter will all be within a two degree circle at dawn.
Full moon (the “Flower/Planting Moon”) occurs on 5/17.
Gray Squirrels Stripping Bark Off Maple Trees
Last year, I received this e-mail from Elizabeth Mazur in Hazelhurst: “This spring before the leaves emerged, I noticed a few trees with places high up on the tree where there were bare bark areas.
“[Later] I noticed a nice, healthy maple in my backyard with "big toothpicks" all around the bottom of the tree. They are several inches in length and from 1/4 to 1/2 inch in width. Similar to what it would look like if you took a piece of bark and pulled strips off of it . . . When I look up into these trees, it is not evident where the strips are coming from. I thought it might be a problem with bugs in the tree, maybe woodpeckers finding them etc. However, I have been watching these trees and see/hear no evidence of woodpeckers favoring these trees.
“Do you have any ideas? Or is there something attacking maples this year?”
My response was that I really didn’t know what could be doing that, and to contact me if she observed anything new.
So, last week I received this e-mail from Elizabeth: “I had another tree last fall with a ton of bark pieces around the bottom, right about the time of the huge wind storm. No other evidence over the winter until about 2 weeks ago. I observed gray squirrels actually laying on the branch of the tree and pulling strips of bark off. There was also a "black squirrel" as part of the group. If I had not seen it early in the morning, I would still not know the answer. In the past, it had happened overnight or in the pre-dawn hours. Now that I look into the woods, I notice lots of stripped branches. I am hopeful that it is not all done by squirrels.”
My speculation is that the gray squirrels are licking the sap from the maples. Red squirrels are known to bite sugar maples and then lick the sap, so it’s certainly possible that gray squirrels are even more aggressive in their desire for the sap.
If anyone has any other explanations or observations, I’d love to hear them!
While ice-out came later this spring than usual – April 22 on Foster Lake, six days later than the 38-year average according to Woody Hagge’s records – this spring was nothing compared to 1996 when ice-out for nearly all our inland lakes came well into May. Foster Lake didn’t shed its ice that year until May 7, and Trout Lake didn’t lose its ice until May 17.
So, yes, absolutely, it’s been a cool and drawn-out winter-into-spring. But, keeping things in perspective, it’s not been all that unusual for northern Wisconsin.