Wednesday, October 15, 2014

NWA 10/3/14

A Northwoods Almanac for 10/3 – 10/16/14 

Pillaging Robins
            In mid-September, our largest mountain ash tree was laden with orange-red berries, the key word in this sentence being “was.” A flock of robins arrived on 9/15 and, in just one day, stripped the tree bare.
Mary and I were both distressed by this and actually tried to shoo them away numerous times, not because we don’t like robins, but because our mountain ashes provide a great lure for winter birds visiting from Canada. Pine grosbeaks, evening grosbeaks, bohemian waxwings and others love the fruits, and in turn, we love to see them. Now the mountain ash won’t look any more appetizing than any other bare-limbed tree on our property.
I have to laugh at myself for not wanting the robins to eat the fruits prior to their migration – after all, they need to eat, too. Who am I to value a winter pine grosbeak over an autumn robin? But since robins are perhaps the most versatile foraging bird in North America, I’d like them to eat something less necessary for our wintering birds. After all, one study of their stomach contents found fruits of 50 genera and invertebrates from more than 100 families, illustrating how robins can live just about everywhere, and can eat just about everything, from worms in summer suburban lawns to seeds from trees on mountain peaks. They forage in the air snatching insects, grab fruits off vines, lift leaves on the forest floor to find invertebrates, and even partake of an occasional frog or fish or snake.
It would be one thing if they had no choice but to eat the mountain ash berries in order to migrate. Their theft is like someone eating all the canned goods that you put up for the winter, when they could have eaten the fresh greens in the garden.
Enough whining on my part. Robins are on the move south, as evidenced by the huge numbers that have already been counted at Hawk Ridge in Duluth. They only go as far south as necessary to get beyond the heavy snows, so they are a common wintering species in states like Ohio, Indiana, and Illinois, forming large roosting flocks from which they track sources of berries. They move throughout the winter after they’ve decimated nearby food resources, thus their Latin species name migratorius means “wandering” as well as “migratory,” a highly appropriate description for their winter behavior.

Hawk Ridge Visits
Last week, Mary and I, along with a group from Nicolet College, traveled up the North Shore of Minnesota, stopping at Duluth’s Hawk Ridge on the way there and back. On 9/17, we arrived at the ridge at 12:30, but cloud cover and a strong easterly wind whipped up just as we got there. As the hawk counters noted on their website, “Clear and calm early this morning with mild temperatures. A pretty good flight before the wind shift killed it.”
Still, they counted 2,451 broad-winged hawks among the total of 2,941 raptors! While we missed the big numbers, we got numerous good views of sharp-shinned hawks. An additional 8,222 migrating non-raptors flew over the ridge that day, including 5,835 blue jays.
We came back through Duluth on 9/20 and had what appeared to be the perfect conditions for a great flight. The previous two days had easterly winds, resulting in miserly counts of 39 and 80 total birds. So the birds were stacked up and waiting to go when the wind shifted to the west-northwest. We got up on the ridge by 10:30 and stayed until 1:00. We were treated to excellent and frequent views of low-flying sharp-shinned hawks, as well as numerous eagles, turkey vultures, northern harriers, broad-winged hawks, and kestrels, and one each of a peregrine falcon, a red-tailed hawk, and a Cooper’s hawk. But we had to leave by 1:00 to make it home. And that was too bad, because as the counters noted on the website, “A wonderful flight really ramped up in the last few hours of the day. Excellent diversity. Great looks at multiple low broad-winged hawk kettles in addition to a couple of adult Swainson's hawks and a subadult golden eagle.” The total for the day was 2,783 broad-winged hawks along with 934 sharp-shinned hawks. They also counted 5,095 migrating non-raptors, including 3,331 blue jays and 747 American robins.
The next day took the cake, however, with perfect northwest winds producing a huge flight of 7,219 broad-winged hawks. The counters described it as an “overwhelming flight of birds. For a while in late morning, thousands of non-raptors mixed with thousands of raptors, a counter’s worst nightmare.” They also counted 17,633 migrating non-raptors, including 5,259 unidentified warblers and 2,166 white-throated sparrows (record high count).
Those are the days one dreams of observing, and we missed it by one day! Still, we saw more hawks on our two visits than most people see in a lifetime. The days were lovely, the camaraderie excellent, and the birds beautiful in flight – what better way to spend autumn afternoons!

North Shore Shorebirds – Pipits and Sanderlings
            The highlight of our birding along the North Shore of Minnesota was our time in and around Grand Marais. We stayed at the incredible Naniboujou hotel, which was worth the trip alone, but which also sits right on Lake Superior adjoining the Brule River where it empties into the lake. Here we had good views of a semi-palmated plover and a black-bellied plover, and incredible views of sanderlings, which one morning walked within a few feet of where we were standing, apparently unfazed by our presence.
Sanderlings, a small, plump sandpiper, breed on the high-arctic tundra, their circumpolar breeding range extending from the Canadian Arctic to Greenland and arctic Siberia. In North America, it winters in relatively small numbers along the Atlantic, Pacific, and Gulf coasts, but most winter in Central and South America. They typically forage on sandy beaches, running quickly ahead of incoming waves and chasing after receding ones, probing the sand for food. Their average migration distance covers 77° of latitude with some flying more than 6,000 miles to reach temperate South America!
We also had close-up and lengthy views of American pipits, a species Mary and I had never seen before. A small flock foraged continuously on the shoreline rocks, and it took us over an hour to finally figure out what they were – so much for any pretense of expertise in birding!
Pipits are one of a very few species of ground-inhabiting songbirds that breed at high altitudes in alpine meadows and on the arctic tundra. They winter in the southern U.S. and down into Central America, so we see them only briefly in spring and fall migration.

Sightings – Spotted Salamander
Ron and Pam Ahles on the Pike-Round Lake Chain sent me a photo on 9/22 of a spotted salamander that was crossing their driveway. They noted that it was the first one they had ever seen.
            Salamanders are a secretive group, so it’s not surprising Ron and Pam have never seen one – we rarely see them as well.
            The spotted salamander spends most of its time underground, under logs, or in heavy groundcover vegetation, but warm, rainy nights often encourage them to move overground. Given the time of year, this one may have been heading for its hibernation site, but it’s a bit early – the literature says they go underground later in October. They appear to not be freeze tolerant, so they don’t really "hibernate," but rather find somewhere to spend the winter that doesn't freeze, perhaps in abandoned small mammal burrows or other soil openings below the frost line.
            The females mate in ephemeral woodland ponds very shortly after the ice goes off in a “mass nuptial orgy” and lay their eggs. After about 60 days, perhaps around the end of June, the larvae hatch and then metamorphose typically in mid-August.
            We should be thankful for salamander populations, because in their aquatic larval stage, they consume vast quantities of mosquito larvae and other small invertebrates. “So what,” some might say – there can’t be enough of them to matter since very few people ever see them. But researchers say they have a very high density in deciduous forests – over 1,000 per acre – which far exceeds the biomass of breeding birds, and equals that of small mammals.

Wisconsin Conservationist of the Year – Matt Dallman
            Matt Dallman, The Nature Conservancy’s Director of Conservation for Northern Wisconsin, was named Conservationist of the Year by the Gathering Waters Conservancy. Matt’s office is in Minocqua, where he has worked for many years helping to protect northern forests and waters. He’s negotiated some very challenging land deals, earning a trusted reputation with diverse interest groups and individuals. This is a prestigious award and well deserved – kudos to Matt.

Mushroom of the Week – Barometer Earthstar
            Our most interesting recent mushroom find was a barometer earthstar on the Cascade River State Park hiking trail near Lutsen, Minnesota. The outer layer of the mushroom splits into rays like a star and is topped by a small, whitish globe-like structure which contains the spores. What’s amazing about this mushroom is that it responds to changes in the weather, much like a barometer. In dry weather, the rays close tightly, while in wet weather, the rays open, bend back, and raise up the spore sac so the rain can help disperse the spores.



Celestial Events – Lunar Eclipse!
            A total lunar eclipse will occur during the full moon on 10/8, beginning at 3:27 AM and reaching full eclipse from 5:27 to 6:22 AM at which point the moon will be close to the horizon and soon to set at 7 AM.      


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