Friday, May 19, 2017

Kingfisher

Fresh sunshine warmed my bare arms and legs as I biked along County Highway D east of Lake Namakagon. The joy of speed, freedom, and my trusty steed brought on an irrepressible smile. As we neared the bridge over a marshy flowage, a cacophony of bird songs began to cut through the whirr of tires on pavement and wind in my helmet. We pulled over onto the shoulder for a better look.

Red-winged blackbirds gurgled and trilled their early spring song that is so energetic it seems to cause ice to melt and streams to flow. A pair of Canada geese honked harshly from their grassy hummock; building their pair bond by shouting together. And then a rattling cry ripped through the air. My head snapped up automatically as I followed the sound and the blur with both my ears and eyes. Finally my focus landed on a slate-blue shape just settling on the branch of a broken snag.

“Kingfisher,” I said out loud, even though we both knew it already, as I whipped binoculars out of my bag. Just back from Central America, his breast was pure white with a jaunty blue band to match his powder-blue tux. A female would have had a beautiful rusty bar across her belly. Belted kingfishers are one of the few bird species where the females are more colorful than the males.

Belted Kingfishers are one of the few birds where females are more brightly colored than the males.


In the next moment I realized that he had something in his mouth—a large minnow probably—and he was whacking it against the branch over and over with sideways jerks of his head. At some point he decided that it was sufficiently dead. He tipped his head back, gave the fish a little toss, and down the hatch it disappeared!

While this minnow was comfortably bite-sized, kingfishers, who are thirteen inches long at most, have been known to eat fish up to seven inches long. Their trick? They leave part of the fish hanging out of their beak until stomach juices digest enough of the fish that it can slide in all the way. Also, the bird’s tiny tongue stays out of the way.

Young kingfishers have such strong stomach acids that they can digest fish and crayfish completely—bones, shells, and all. Once they leave the nest, kingfishers regurgitate pellets filled with the indigestible bits, just like owls do.

Those young belted kingfishers, who hatch in May or June, keep their parents busy by consuming their body weight in food each day. Luckily, kingfishers live up to their name with the help of several adaptations.

First, they can scope for prey either from a poolside perch or by hovering in one place high above the water. Like many birds, kingfishers have excellent eyesight. Oil droplets on their cone cells enhance their color vision and reduce glare as they search for prey. Two focal points in their eyes allow them to adjust for the change in refraction between air and water as they dive after a fish. The position of these two foveae gives kingfishers monocular vision in the air (each eye is used separately) and binocular vision underwater (which allows them to judge distance). A third eyelid, called a nictitating membrane, acts like protective goggles.

When a kingfisher dives underwater, its sturdy, conical beak wedges into the water and pushes it aside with minimal impact or splash. Japanese bullet trains, which operate at speeds exceeding 200 miles per hour and carry more passengers than any other rail line in the world, imitate the aerodynamics of the kingfisher’s beak to reduce noise pollution and improve fuel efficiency.



After grabbing the fish or crayfish with its vise-like bill, the kingfisher flies up to a perch to whack away, just like I witnessed. The chicks are fed small fish or regurgitated food. As the young grow up, parents teach kids to hunt by dropping fish into the water for the students to retrieve, just like in common loon families.

While their hunting adaptations are amazing, the kingfisher’s strangest adaptation is used for digging their nest burrow in a sandy embankment. Their inner two toes are fused together, resulting in what appears be a single flattened toe. This trait, called syndactyly, is not common, but it is shared by kangaroos, wallabies, opossums, koalas, and wombats.



I will never cease to be amazed by the ways that nature has sharpened its every skill and perfected its many tools for survival. As we hopped on our bikes (wonderful products of human adaptation and innovation) to continue the ride, an osprey soared overhead, itself a magnificent example of adaptation. Admiringly I glanced back toward the kingfisher, and “with a rough and easy cry…he swung back over the bright sea to do the same thing, to do it (as I long to do something, anything) perfectly.” (Mary Oliver, “Kingfisher”)

Special Request: If you enjoy Emily's book, Natural Connections: Exploring Northwoods Nature through Science and Your Senses, and think it should be available for more people to read, then take a moment and request it at your local library and bookstore! Order your copy at http://cablemuseum.org/natural-connections-book/.  Listen to the podcast at www.cablemusum.org!

For 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. Come visit us in Cable, WI! Our new exhibit: "Better Together--Celebrating a Natural Community" is now open!

Friday, May 12, 2017

An Ephemeral Mystery

On one of those damp, gray days in early April, I joined the North County Trail Navigators to hike a brand new section of trail east of Copper Falls State Park, near Mellen, WI.



Sara, one of the group's founder, found a beaver chew!

Light was low, but our spirits were high. Many of these women completed the 100-mile challenge on the North Country Trail (NCT) for the National Park Service’s birthday last year. Now they’re addicted, and are trying to hike this year’s miles before the mosquitoes hatch.

Joan found a bird nest.


From the gravel road where we parked, the trail snaked its way through a beautiful sugar maple forest. The rich soil, typical of maple forests, was soft and loamy. Great for plants, but not for hiking boots. We giggled, whooped, and exclaimed as we slipped and slid through mushy spots. With use, the soil will compact and become a more durable tread, but ours were some of the first boots to travel here.

I was at the end of the line, chatting away, when I heard my name called up ahead. One of the women had spotted a mystery near the trail. In several patches, each about the size of a manhole cover, the thick maple leaf duff was pushed away. Laying exposed on the black soil were scattered chains of yellow-green plant roots that reminded me of the little plastic pop-together necklaces I won at carnivals as a kid. Each segment of the rhizome was an oval-shaped “bead.” Also visible were the lacy network of regular, thin roots.

Many of the spring flowers that like to grow under maple trees survive most of the year just as underground roots, rhizomes, or bulbs. Photo by Emily Stone.

Of course, with a naturalist along, the group wanted an explanation of what we’d found. I pulled out my camera to photograph the creeping rootstocks, but couldn’t put a name on the discovery. A few tiny clusters of curled-up leaves sprouted from the ends of the segments, but they weren’t big enough for a confident identification. All I could do for the ladies was list of a few possibilities: blue cohosh, trout lily, spring beauty, trillium, Dutchman’s breeches, wood anemone…the list of possibilities was long.

One thing that I was certain of was that these roots belonged to a spring ephemeral. This category of flowers completes their entire life cycle in the two months or so between snow-melt and leaf-out. Instead of adapting to grow in the oppressive shade of the summer forest canopy, these little plants take advantage of the full sunshine of early spring.

During their brief growing season, spring ephemerals bury an energy reserve in tuberous roots, modified underground stems, or bulbs. Those storage units lay dormant—and protected from drought or cold—through the winter. Come spring, leaves and flowers erupt quickly with the plentiful moisture and sunshine, provide food for early pollinating insects, and then restock their provisions before melting away under the deepening summer shade.

Because so many of the spring flowers that inhabit maple forests have similar strategies, the roots we found could potentially belong to any number of the sweet and beloved blooms that grace each spring. To me, this was the most interesting part of the mystery. I did, of course, do some research at home to try and match these particular roots with a name. It’s hard to find good, identifiable photos of roots, though. Happily, the challenge just meant that in order to solve the mystery with confidence, I would have to return to this beautiful trail once the leaves had expanded.

My chance came two weeks later. The trail was only slightly dryer, but the scenery had gone through a delightful change. Little green leaves pushed up everywhere, but mostly they sprouted out of the trail itself, where dark soil had warmed more quickly than the pale duff. Trout lilies, trilliums, leeks, oh my! And then I noticed a small patch of those mysterious, yellow-green segmented roots. Erupting out of their tips were the tiny palm tree-like leaves and clustered flower buds of cut-leaved toothwort. Mystery solved.

Each spring, the sugar stored in cut-leaved toothwort rhizomes fuels the growth of leaves and flowers. 
Photo by Emily Stone.


Cut-leaved toothwort (Dentaria laciniata or Cardamine concatenate) is a widespread spring ephemeral in the mustard family. Its common name describes both the narrow, toothy leaves, and also the canine tooth-shaped sections of it rhizomes. Its elongate cluster of pretty white flowers will each have four petals. True to its family, the leaves and the rhizomes of toothwort have a spicy taste, similar to wasabi. The flavor probably deters some herbivores, but it’s actually encouraged people to use it as a condiment and a medicine over the years. I chewed on a leaf, and it tasted like a very plain mustard.

One herbivore that isn’t deterred is the caterpillar of the West Virginia White, a Wisconsin State Special Concern butterfly. The butterfly lays eggs on a few species of native toothworts, and the caterpillars must grow up before their short-lived food plants senesce for the summer. In an unfortunate twist, the non-native, invasive garlic mustard shares chemical cues that attract egg-laying butterflies, but it provides inadequate nutrition for the caterpillars.

In any case, it was fun to identify friends along the trail as we all race to make the most of spring.

Cut-leaved toothwort is one of the earliest flowers to bloom. Its four petals range from white to pink, and they often droop until the sun comes out. Photo by Emily Stone. 


Special Request: If you enjoy Emily's book, Natural Connections: Exploring Northwoods Nature through Science and Your Senses, and think it should be available for more people to read, then take a moment and request it at your local library and bookstore! Order your copy at http://cablemuseum.org/natural-connections-book/.  Listen to the podcast at www.cablemusum.org!

For 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. Come visit us in Cable, WI! Our new exhibit: "Better Together--Celebrating a Natural Community" is now open!

Friday, May 5, 2017

Garlic Mustard

It’s hard to go anywhere with me in the spring. We were still within sight of the cars when I spotted my first Dutchman’s breeches leaves and veered off the trail. Fresh raindrops glistened in their clusters of lacey, blue-green foliage, and a few plants hosted spikes of tightly closed buds. 


Tiny whorls of wood anemone drew me further into the silver maple floodplain forest. Once I was there with my nose down, the jagged leaves of toothwort jumped into view, followed by the mottled leaves of trout lily, and an elegant bloodroot bud, still clasped protectively by its leaf.




The rich soils and brief spring sunshine in this deciduous forest create the perfect habitat for a carpet of my favorite spring wildflowers. The brief appearance of these flowers each year endows them with the value and mystique reserved for things that are both beautiful and rare.

Adam Haecker, Coordinator for the Northwoods Cooperative Weed Management Area (NCWMA), was waiting for me by the trail when I wandered back. He stood resignedly over a whorl of emerald green leaves, much brighter than all the others. We each picked a roundish leaf from the cluster and crushed it under our noses. The spicy scent confirmed my hunch: garlic mustard.




Garlic mustard, Alliaria petiolate, is a non-native species that invades disturbed areas, and also high quality uplands, floodplain forests, and savannas. It’s a biennial, which means that first-year plants grow rosettes of emerald, kidney-shaped leaves with scalloped edges, while second-year plants grow taller stalks with heart-shaped leaves and clusters of small, white, four-petaled flowers. Garlic mustard is pretty, and some people enjoy the flavor (although my one attempt at pesto was bitter), which is why settlers brought it here from Europe in the 1800s.



The problem with it on this continent, though, is that garlic mustard releases anti-fungal chemicals that disrupt the important relationships between native plants and mycorrhizal fungi in the soil. Through sheer quantity, then, it goes on to push out our beautiful—and increasingly rare—spring flowers, and even hinders tree regeneration. The loss of native plants affects insects, herbivores, and more—all the way up the food chain to our friends and loved ones who are spring wildflower enthusiasts.

I grew up pulling garlic mustard’s odorous leaves out of our woods in Northeast Iowa, but hadn’t yet encountered it since moving to northern Wisconsin. We have a lot of acidic soils up here, which aren’t good for either garlic mustard or most spring wildflowers. The downside is that the special, rich woods where I go to see my favorite spring flowers are the ones that are at risk of invasion.

Luckily, garlic mustard is not yet common in the Northwoods. Adam and the NCWMA would like to keep it that way.

The Northwoods Cooperative Weed Management Area is “a collective group of state and federal agencies, municipalities, tribes, nonprofits, community organizations, and individuals who have come together to combat invasive species in Douglas, Bayfield, Ashland, and Iron counties in northern Wisconsin.” I’m impressed by the cross-agency cooperation, and by their accomplishments.

Garlic mustard was discovered in 2007 on this 75-acre site along the Bad River floodplain in Mellen, near Copper Falls State Park. Its position in the floodplain gives a likely explanation of how the invading seeds arrived. For that same reason, controlling garlic mustard so that it doesn’t spread farther downstream is a high priority for the NCWMA. The land is mostly privately held, but the owner has been supportive of the garlic mustard removal efforts.

Each spring, a group of about 30 natural resource professionals from the NCWMA, plus volunteers, descend on the site and do their best to eradicate the spicy, bright green leaves. Hand pulling is the most common method, but it must be done with care. Plants can re-sprout from broken roots, and the flowers can set seed even in a heap. The workers carefully haul out all plant remains in heavy garbage bags.

Garlic mustard stays green all winter, while native plants are dormant. On the shoulder seasons it’s possible—using extreme caution—to use a glyphosate herbicide on extensive infestations.

No matter which removal method is used on a site, part of the project’s success is a dedicated effort. Each garlic mustard plant can produce more than 100 seeds, and they remain viable in the soil for around seven years. Repeated pulling is essential.

The NCWMA’s efforts are paying off. Plots on this floodplain that were once covered in thick patches of garlic mustard now only sport a few first-year plants. Another site along the Montreal River, near Hurley, WI, is receiving the same treatment and seeing similar, positive results. The keys to success are early detection, landowner involvement, and a dedicated removal effort.

The public can be a big help in thwarting the spread of this pretty little fiend. Hikers can clean the mud off their boots between trails, so as not to transport the seeds. Anyone can
volunteer with the NCWMA on fieldwork days. (There’s one coming up on May 9!) Everyone can keep an eye out for it and other invasive species, and report sightings to Adam at the NCWMA by calling 715-373-6167 or emailing ahaecker@bayfieldcounty.org. If landowners discover garlic mustard on their property, a quick call to the NCWMA, WI Department of Natural resources, Great Lakes Indian Fish & Wildlife Commission, or any other local natural resources agency will initiate a process that includes a site visit, inventory, and plan for removal. The Wisconsin DNR website is an excellent resource for tips on identification, prevention, and control.

While garlic mustard receives a lot of attention, particularly because it’s still rare enough to have a chance at control, the NCWMA also organizes removal efforts for Japanese knotweed, wild parsnip, purple loosestrife, and a whole list of other invasive species. You can find more information on their website: http://www.northwoodscwma.org.

After finding that patch of garlic mustard, Adam and I explored a little farther down the trail. Silver maple trunks arched gracefully above, but my eyes were on the ground. Despite our searching, we couldn’t find another cluster of the invasive plant. What we found—thanks to the hard work of the NCWMA—was a beautiful diversity of spring flowers, just getting ready to bloom.



Special Note: This article was written in partnership with the NCWMA.

Emily's book, Natural Connections: Exploring Northwoods Nature through Science and Your Senses is here! Order your copy at http://cablemuseum.org/natural-connections-book/.  Listen to the podcast at www.cablemusum.org!

For 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. Come visit us in Cable, WI! Our new exhibit: "Better Together--Celebrating a Natural Community" will open on May 2!


Friday, April 28, 2017

Sensing Spring

After a day of rain, the clouds parted and a setting sun made the world sparkle. It felt like a sacrilege to stay inside. You just don’t ignore spring. Taking my camera for a walk along the driveway (I have a really lovely driveway), I ambled slowly, stopped often, and absolutely wallowed in the ecstasy of a warm, meditative walk with no mosquitoes.


Deep breathing came naturally in this mood and in this weather. The air was delicious. Damp soil, decomposing leaves, and that spicy essence of new life swirled around me so richly it was almost visible. But being visible isn’t everything.

“The true essence of nature can be captured only by making use of all our senses, and the sense of smell is not the least of these,” wrote Lois Nestel in her infinite wisdom. As the first Naturalist and Director at the Cable Natural History Museum, Lois once shared her insights generously with newspaper readers across the state. I’d like to share it with you again.

“In this season, when one is keenly aware of the scents of the earth, the fragrance of spring flowers is expected and perhaps taken for granted: The delicate perfume of arbutus and the tiny white violets that grow on moist soil, the richness of wild roses and, later, the heavy fragrance of pyrolas. But there are drifts of odor so elusive that, caught with one breath, they are gone the next. The faint tang of newly opening leaves defies description—a touch of spiciness, an intangible freshness that is purity, yet something more.”



“While walking down a woods road on a warm day it is possible for a person sensitive to odors to recognize, without seeing, the type of foliage through which one is passing. Each is distinctive: the fresh cleanliness of newly opened aspen leaves, the slightly acrid oak, sweet blooming basswood and the unforgettable odor of sun-warmed evergreens: spruce and balsam, pine and hemlock…These scents are tantalizing, haunting, often bringing a flash of memory from forgotten days…One may not know them by name, but the scent is as familiar as an old friend.”

“Odors play a greater part in our lives than we may realize. Have you not at some time had a situation suddenly recall a scent so clearly that it seems momentarily to fill the air? It might be one of many things—a lake at dawn, a dusty summer road, freshly cut grass, hay drying in the sun, or the deep primordial scent of swamp and bog.”



“A swirl of warm, aroma-laden air from a hillside, a draft of cool cleanliness from a hollow may awaken vague stirrings of the spirit; yet we can only appreciate but cannot interpret, as do animals, all that the scented air contains. But thus may we, at no cost and little effort, enrich our lives; if we fail to do so we have deprived only ourselves.”

While the scents of spring are indeed lovely and worth noticing, the flowers of spring may occasionally outshine them. Lois wrote charmingly of these, too.

“All the tender shades of spring are now unfolding. All the hues of autumn are here, only in tones more delicate and subtle. Soft shades of pink and wine and the daintiest of yellow blend with the sheerest of green as buds unfurl and fragile leaves and blooms unfold.”



“At a distance forest and brush land wear watercolor shades and soft washed pastels. Tree blossoms, seldom noted, are small perfections deserving closer examination and appreciation. Well known are juneberry, cherry and plum blossoms, hawthorn and red elderberry; less commonly recognized, though equally beautiful in a miniature way, are the flowers of the maple and oak—delicate clustered flowers of russet, rose and yellow dangling on slender pale green stems—or the willows, their catkins now masses of gold and chartreuse.”



“Wood flowers bloom now before leaf shade from trees cuts down their light. Bloodroot leaves embrace the stems of snowy, golden-eyed flowers and hepaticas, spring beauties and wood anemones nod heads of lavender, pink and white, while trailing arbutus perfumes the air from pale, clustered blossoms. Soon trilliums will dance beneath the trees and the marshlands will glow yellow with marsh marigolds, rosy with bog laurel, and white with Labrador tea.”



“Shade on shade, tone on tone, the palette of nature is spread with her most gentle colors. The harsh, the gaudy may come later but now is the time for tenderness.”

Now is the time for tenderness. Deep breathing, slow walking, and (don’t take it for granted!), a delightful lack of mosquitoes.

Special Request: If you enjoy Emily's book, Natural Connections: Exploring Northwoods Nature through Science and Your Senses, and think it should be available for more people to read, then take a moment and request it at your local library and bookstore! Order your copy at http://cablemuseum.org/natural-connections-book/.  Listen to the podcast at www.cablemusum.org!

For 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. Come visit us in Cable, WI! Our new exhibit: "Better Together--Celebrating a Natural Community" will open on May 2!


Friday, April 21, 2017

A Swarm of Wiggling Swimmers

Even through closed windows I could hear the rough quacks of wood frogs and the clear chimes of spring peepers rising from the wetland. A loon’s haunting wail echoed across the lake. Stars twinkled. No mosquitoes buzzed. And the temperature still hovered above 50 degrees. Perfect nights like this only come twice a year: in spring and in fall.



Even though I had planned to head upstairs for bed, I paused at the front door, slid on my muck boots, grabbed a flashlight, and slipped out into the night.

The air felt cool and fresh as I tromped down to the shore. No breeze stirred the trees. After I stepped out onto the wet sand at the water’s edge I stilled my body and opened my senses. Frog calls came in stereo from multiple wetlands around the lake. Actual ducks joined in the wood frogs’ quacking, and somewhere out on the liquid ebony, geese honked sporadically like kids settling in at a sleepover.

As my eyes adjusted, the number of visible stars made the sky look foggy, although two pesky yard lights from across the bay really infringed on my night vision. After a few deep breaths, I switched on the flashlight and turned to go. The light caught on layers of brown leaves, just slightly suspended above the sand, gently rocking back and forth in the ripples caused by my rubber boots. And something zipped across the flashlight’s halo.

Crouching down, I discovered a swarm of tiny swimmers, each less than half an inch long. Some wiggled through the water column, some zipped across the sand and leaves, and some froze in the spotlight. Enchanted, I watched carefully and tried to identify these little benthic macroinvertebrates. (Benthic = bottom dwelling, macro = visible without a microscope, invertebrates = no spine.) The swimming ones were just bundles of wiggling appendages. Then I finally focused in on one of the critters resting on the sand. Three thin tails spread out from the tip of its abdomen, and I could imagine them drawing a stylized letter M. M is for mayfly.



This flock of little water wigglers will one day shed their exoskeletons and spend from a few frenzied hours to a few glorious days as winged adults. Mayflies belong to the order Ephemeroptera, which is named from the Greek words meaning “short-lived” and “wing.” And while it’s true that mayflies are short-lived once they have wings, their immature, flightless, aquatic nymphs can actually live for several years.

That nymph stage is what swam through my light beam. Two antennae projected off one end. Three thread-like tails arched gracefully off the other. In between were three pairs of legs on the thorax, and two fringes of undulating gills, which were arranged in seven pairs along the abdomen.

After hatching, mayfly nymphs may molt through 30 instars as they grow. Chewing mouthparts help them feed on algae and dead stuff. A few species predate on other, smaller, invertebrates as well. Some species of mayfly nymphs burrow into the lake bottom and billow their gills to stir up sediment. Not only does this allow them to filter feed on “periphyton,” (which is basically that scum of both living and dead things that coats objects in a lake), it also stirs up nutrients that phytoplankton and other critters can use.

Their feeding habits make mayfly nymphs fairly sensitive to pollution. Acidification, sewage, pesticides, and industrial effluent are particularly harmful, and their impact on mayflies can throw the whole food chain out of whack. Algae might take over like weeds, and their fish predators may starve or just concentrate the pollution in their own bodies. On the flip side, the presence of mayfly nymphs can tell us that our water is clean without a lot of expensive tests.

While mayflies may live for years in their nymph stage, their adult stage is what brings them fame. In several species, the emergence of adults is synchronized, in order to overwhelm all of their predators. The clouds—and drifts—of mayflies are sometimes visible on weather radar and can cause slippery roads. Anglers imitate them carefully.



Mayflies are the only insects that have a winged, terrestrial, but not sexually mature stage. When a nymph reaches its final instar, it sheds it exoskeleton one more time. What emerges is a dull-colored winged creature who (usually) cannot yet mate. These subimago are both poor flyers and excellent fish food. After a few minutes to a few days, the subimago sheds its exoskeleton and becomes a brightly colored, fully functional imago (adult).



As adults, mayflies resemble some of the very first flying insects. The long, thread-like tails that I used to identify the nymphs stick around in the adult form. Their clear, vein-riddled wings do not fold flat over their abdomen and are held upright while at rest. Mating is quick, egg-laying prolific, and death follows closely.

I wonder how much longer this swarm of tiny swimmers in my lake needs to grow? Later this summer I’ll probably paddle through a scum of their shed exoskeletons and ephemeral, winged bodies. For now, I’ll just enjoy watching the wigglers on an otherwise bug-free night.


Special Note: Emily's book, Natural Connections: Exploring Northwoods Nature through Science and Your Senses is here! Order your copy at http://cablemuseum.org/natural-connections-book/.  Listen to the podcast at www.cablemusum.org!

For 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. Come visit us in Cable, WI! Our new exhibit: "Better Together--Celebrating a Natural Community" will open on May 2!