NWA 10/30/15

A Northwoods Almanac for October 30 – November 12, 2015  by John Bates

Wisconsin Bird Atlas

The collection of data for the second edition of The Atlas of the Breeding Birds of Wisconsin began this spring, and in just over six months, 700+ Atlas volunteers surveyed 2,600 Atlas blocks, and submitted 23,900 checklists, documenting 1.7 million birds. In this first of five seasons in which data will be collected, 229 possible breeding species were recorded, and 212 species were confirmed to be breeding. In the first edition of the Atlas, 237 possible breeding species and 226 confirmed species were reported, so the project is already close to those totals. Exciting discoveries include sightings of eight species nesting in Wisconsin that weren't found here at all 15 years ago, and dramatic range shifts in other species, such as the wild turkey. The eight new nesting species include:

Bufflehead (1 confirmation)

Whooping Crane (multiple confirmations)

Eurasian Collared-Dove (4 confirmations)

White-eyed Vireo (1 confirmation)

Great Tit (2 confirmations)

Kirtland’s Warbler (multiple confirmations)

Yellow-throated Warbler (1 confirmation)

European Goldfinch (4 confirmations)

It should be noted that European goldfinch and great tit are non-native species that, as popular cage birds, have been inadvertently introduced into the wild from captivity. Whether they’ll spread throughout the state isn’t known.

Snowy Owl Invasion!

Significant numbers of snowy owls have already arrived in Wisconsin – 25 had been confirmed as of 10/22 with the first one seen on 10/15 in Ashland. These unprecedented reports are earlier in the season and higher in number than any year on record. Last year, the first snowy was reported in Wisconsin on 11/1, while in 2013, the initial observation was 11/15. The first snowies typically appear in Wisconsin in mid-November.

            Large southerly flights called "irruptions" have historically occurred about once every four or five years. But Wisconsin experienced snowy owl irruptions in 2011-'12, 2013-'14 and 2014-'15. In 2013-2014, a record 290 snowies were recorded in the state, which was almost equaled last winter when 280 snowies were counted. So, this winter looks like it will be the third irruption in a row and fourth in five years. In a “normal” year, perhaps 30 birds might be seen.

So, what’s going on? One researcher, Tom Erdman in Green Bay, suspects climate change. He said a warmer Arctic could be increasing the abundance of lemmings, the favorite prey of snowies, fueling snowies to produce more offspring more often. In a really good year, a pair of adults may fledge 10 young owls. But the lemmings are insufficient in winter to feed the overabundance of young snowies, so they’re forced to move south.

The snowies that migrate into Wisconsin often arrive exhausted and hungry. Since it's difficult to tell the difference between a healthy owl and one that is sick or injured, if you see one it’s important to call a local DNR wildlife biologist or wildlife rehabilitation center. Snowy owls prey mostly on voles and other rodents in Wisconsin, as well as some birds.

Oregon Long-Term Ecological Research

Mary and I have spent the last two weeks in Oregon, nearly all of the time at the H.J. Andrews Experimental Forest in the western Cascades Mountains. First established in 1948, the H.J. Andrews is a 16,000-acre ecological research site home to iconic Pacific Northwest old-growth forests of western red cedar and western hemlock, and moss-draped ancient douglas firs; steep terrain; and fast, cold-running streams. In 1980, the Andrews became a charter member of the National Science Foundation's Long-Term Ecological Research (LTER) Program, which now supports 26 sites across North America (including the Trout Lake North Temperate Lakes LTER site near Boulder Junction).

The forests at Andrews are among the tallest and most productive in the world, with tree heights often greater than 250 feet. When established in 1948, the Andrews Forest was covered by a mix of old-growth conifer forest (around 500 years old) and mature forest (100-150 years old). The old-growth forests became the subject of intensive basic research in the 1970s, and has since spawned literally hundreds of technical studies.

Mary and I were selected to participate in their Long–Term Ecological Reflections program, which since 2004 has created a growing body of arts and humanities works closely linked with the LTER program in the forest. The project hosts writers' residencies where participants can interact with research scientists as they go about their work. Our writings and artwork will become part of a collection spanning hundreds of years, and that is gathered in permanent archives at Oregon State University, as well as being accessible via the Web.

            The concept is simple: science in the absence of the humanities often struggles to effectively communicate its findings. As their website states, “there is an unusual richness and joy in the community of art and science, in the coming together of insights from many different perspectives and disciplines.”

            So, we spent 12 days hiking, writing, and sketching at the Andrews and adjoining areas, trying to absorb as much as we could about the ecology of the area, the historical uses of the forest by the native people, and the social issues associated with old-growth in the Pacific Northwest.

            Some highlights of what we learned include our insight into the essential nitrogen-fixing abilities of a lichen that literally drapes the high canopy of the old-growth. Lobaria oregana, or lungwort, can weigh up to 500 pounds dryweight per acre in the canopy. It acts as a biochemical refinery, processing nitrogen from the atmosphere and converting it to nitrites and nitrates that can be utilized by the all the plants in the forest. The lobaria literally rains down from the canopy, landing on the forest floor and appearing like large kale leaves. The “leaves” decompose, providing up to 22 pounds of nitrogen per acre, though the forest only needs 5 pounds per acre to maintain itself. Thus, a lichen, perhaps the most unlikely of plant origins, provides the largest source of nitrogen to the old-growth forests here. Lobaria only appears in stands over 100 years old, and doesn’t abound until the stand reaches 200 years.

            Another highlight was the astonishing amount and kinds of mosses that cover many of the trees from head to toe. The mosses soak up rainwater and release it slowly, as well as providing a perfect germination bed for tree seedlings on top of fallen trees in the forest. These “nurse logs” harbor remarkable numbers of young trees.

            And then there’s the importance of the underground mycorrhizal fungi, their root-like “hyphae” thinner than a human hair, that connect to the fine roots of the forests’ trees and link them to nearly 1,000 times as much soil area. The trees and fungi have a mutualistic relationship – the trees provide photosynthetic sugars to the fungi, and the fungi provide water and phosphorous to the tree, while also innoculating the soil with antibiotics that kill disease bacteria. In fact, some trees share nutrients between them via a bridge of connecting fungal hyphae. The hyphae, which look like thinnest of white threads, often grow in great tangled mats like a huge net covering hundreds of square feet of soil.

            So, in these most magnificent of old forests, it’s the tiny organisms – the lichens, mosses, and fungi – that make all the difference.

            We also visited and revisited a long-term tree decomposition site, a research effort designed to learn as much as possible about how trees rot over time and what their decomposition offers to the health of the forest community.

            We learned, too, about epicormic branches, where old-growth trees grow new branches well down on their trunks long after the trees have grown far, far taller. These epicormic branches come out in a fan shape and make excellent sites for birds to build their nests.

            There’s a lot more to share, but I’ll end with a plant we viewed when we drove over to the Oregon coast to see the Pacific Ocean. We stopped at the Darlingtonia Natural Area where the California pitcher plant (Darlingtonia californica), or cobra lily, grows by the thousands in a bog. The name "cobra lily" stems from the resemblance of its tubular leaves to a rearing cobra, complete with a forked leaf that resembles fangs or a serpent's tongue. They’re huge! And like our Wisconsin pitcher plants, they are a passive carnivorous trap, baiting in insects, then drowning them in their pitchers.

The cobra lily is unique, however, among the three genera of American pitcher plants in that it does not trap rainwater in its pitcher. Instead, it regulates the level of water inside by releasing water into the trap that has been pumped up from the roots. The plant then releases an enzyme to help digest the insect.