Category Archives: Discoveries

Freshwater Sharks

Snorkeling in frigid waters for a species at-risk

By Levi Old                                                               

Salvelinus confluentusOn a dead-still summer night, I army-crawl upstream.

“We have a large adult!” says Jen.

I rise to one knee and pull the fogged snorkel mask off my head. “A big one?” I mumble in a haze.

“Yeah, really big. Much larger than I’ve ever seen this far up the creek,” she replies, pointing to where it kicked its caudal fin gently against the downstream flow. “It’s right there beside you.”

I cinch the mask on my face, place the snorkel in my mouth, and dunk back into the frigid water:

Twenty-six inches of wildness.

Jen pops her head out of the water and says, “Isn’t that just a beautiful creature?”

She snorkels one side of the creek and I snorkel the other. An assistant in waders walks the creek, tallies our fish sightings and makes sure we do not go hypothermic.

Jen O’Reilly, a biologist for the US Fish and Wildlife Service, leads the recovery effort for the Odell Lake population of bull trout, a Threatened Species under the Endangered Species Act. The recovery team consists of US Forest Service, Oregon Department of Fish and Wildlife, and Trout Unlimited. In order to monitor recovery of bull trout, biologists conduct an annual juvenile count in Trapper Creek, the only known spawning location for this population.

Trapper Creek is a tributary to Odell Lake. In the shadow of Oregon’s Diamond Peak, the lake lies in a glacier-carved basin physically detached from the Deschutes River by a 5,500 year-old lava flow. The flow enclosed the lake, genetically isolating this population of bull trout.

At midnight this past July, ten of us in dry suits and thick neoprene hoodies shimmied up different reaches (Fig. 1) of Trapper Creek. Shallow in most places, the snorkel is more of a crawl and scramble than a leisurely swim upstream. Even in mid-summer Trapper Creek is icy cold.

We closely observed the nooks of each piece of in-stream wood and dove into pools where rapids converged and bubbles enveloped our sightlines. We held dive lights, counted each fish and estimated its size class. We kept our eyes peeled for the creek’s bull trout.

Bull Trout – A species at-risk from Levi Old on Vimeo.

Named for their broad heads, bull trout (Salvelinus confluentus) serve as apex predators in aquatic systems of the West. Often called “Dolly Varden (S. malma),” they are in fact a separate species. Bull trout exist in less than half their historic range and prefer clean, cold waters. As a member of the char genus, they grow to be shark-like beasts in comparison to their trout relatives. Bull trout can measure up to 41 inches and weigh as much as 42 pounds.

Screen Shot 2014-10-24 at 9.34.32 PM
Figure 1: Trapper Creek runs north into Odell Lake. The three primary snorkeling reaches are labeled on the map (Richardson and Jacobs, 2).

The Trapper Creek bull trout population is known as the only adfluvial, non-reservoir population of bull trout in Oregon. During the 20th century, the building of railroads, construction of revetments, and removal of woody debris turned the creek into a large ditch of rushing water, unsuitable for spawning bull trout.

In 2003, this all changed. The recovery team restored the channel to increase spawning and rearing habitat by deconstructing revetments, placing woody debris and rebuilding a meandering channel. The annual snorkel count of juvenile bull trout increased from 26 in 1996 to 150 in 2005. Restoring, sustaining and monitoring native habitat is crucial to the survival of this iconic species.

If you find yourself on western waters, keep an eye out for these stream predators. Light spots of yellow, red and orange cover their dark bodies, and a white margin can be found on the leading edge of their ventral fins. And watch out, anglers: they will steal a hooked fish right off of your line.

Enjoy the video:

Bull Trout – A species at-risk from Levi Old on Vimeo.

Sources:
  • Montana Water Center. (2009). Trapper Creek. Retrieved on October 16, 2014, from http://wildfish.montana.edu/Cases/browse_details.asp?ProjectID=36.
  • Richardson, Shannon and Jacobs, Steve. (2010). Progress Reports. Retrieved on October 16, 2014, from http://oregonstate.edu/dept/ODFW/NativeFish/pdf_files/Odell_BT_Report_final.pdf.

Beyond a Collection of Facts

By Clare Crosby

mtnlaurel

I spent my childhood hosting acorn cap tea parties for fairies, scurrying on calloused feet to collect eggs from the chicken coop, and reenacting Little House on The Prairie in the meadow behind my house, just east of Austin, TX. I did not suffer from “Nature Deficit Disorder.”

But as I grew, my interests shifted. I traded the meadow for well-manicured athletic fields and our old pond for swimming pools. My interest in my Central Texas natural surroundings paused around 8 years old. I never figured out what species of oak provided teacups for my parties, only that the caps were nicely proportioned for fairies. Neither did I learn what type of moss my fairies used for seat cushions, only that it opened into minute stars under sprinkled water.

I’m embarrassed now, as a naturalist, to admit that I don’t know even some of the most common species of my home state. This lack of knowledge, however, offers opportunity when I return to Texas from Vermont, the home of my formal ecological education. As I walk old trails and come across a familiar (yet unknown) tree, my inclination is to turn to field guides or a trusted expert to tell me what to call it, who eats it, and what it might reveal about the soil beneath it. In Vermont, I have had a string of wonderful professors and peers to teach me about the natural world, assisted, of course, by an ever-growing library of field guides. I hope to be so lucky again in Texas. Continue reading

What’s in Your Backpack?

Rattling My Bones

connor

Dripping with cultural history and utterly unique, the objects cradled in Connor Stedman’s excited hands burned with sentimental value. Their glow reflected in Connor’s eyes and didn’t flicker for an instant upon the delivery of my first question.

“So, what are they?”

To the untrained eye, they were two pieces of wood roughly the size and shape of tongue depressors, but slightly heftier and square at the ends. Connor explained it was a set of bones: A historically Irish one-handed musical instrument that is played by holding one bone stationary while rattling the other bone against it.

While the traditional instrument was made from sheep’s bones, Connor’s version originated as the South American tree palo santo, or “holy wood” in Spanish. Palo santo’s use as a good luck charm and a cleanser of bad energy dates back to the Inca era. Connor says that he’s never heard of another pair of bones made from palo santo.

Connor carved his bones in anticipation of a local visit by Irish bard Gerry Brady, who described bones as “the only instrument you can play with a pint in the other hand”. Gerry blessed this set of bones himself. Continue reading

The Burlington Naturalist Scavenger Hunt Series: Williston’s Muddy Brook Wetland

A special series of blog posts brought to you by Liz Brownlee 
The Burlington Naturalist Scavenger Hunt Series: Discover the area’s hidden gems.  Hone your naturalist skills.  Learn to see the treasures along every walking path, trail, and creek.
This series of scavenger hunts is a chance to get outside, look closely at the world around you, and enjoy nature.  The hunts are designed for budding naturalists of any age.
 
Hunt I: Williston’s Muddy Brook Wetland
 
Cruise east, away from the noise of Burlington. Slip south of Highway Two, curving along Hinesburg Road onto Van Slicken Road.  Pass the oldest house in Williston – light grey stones, hand hewn in the 18th century.  Crunch onto the gravel of the parking lot, leave your car (or bike!), and step into the wildness at Muddy Brook Wetland.
Cattails dance on the winter wind, and signs of animals layer this scrubby landscape. To the casual visitor, Williston’s Muddy Brook Wetland rejuvenates and relaxes.  It is a deep breath at the end of the day.
For the budding naturalist equipped with this scavenger hunt, the wetland also offers mid-winter wonder.  Look closely at the ground, the bent grasses, the flowing stream. Find and learn to identify scat, deciduous trees, nests, and other natural treasures. Enjoy!
Find the first scavenger hunt here: Scavenger Hunt- Williston’s Muddy Brook Wetland

Five Bodies

by Danielle Owczarski

I squint as I gaze offshore at the landslide scars jacketing the slopes of the Adirondack Mountains, and become cognizant of the illusion in quiet looking mountaintops, in reality, stark and frigid underneath the winter’s languid sun. I lift the camera to my eye and focus on the lone silhouette of a twisted black willow frozen to the beach, beaten by icy waves. I am in awe of its ability to survive, alone and isolated at the interface of water and earth, defying death.

I am standing on a deserted public beach in Burlington, VT, situated west of the bike path and the Burlington Electric Department. My husband and I, dog in tow and cameras in hand, are in pursuit of stories told by the natural world; those neglected by people behind weatherproofed door jams. During the winter months, protected by the shelter of my apartment, I cannot tune out the arctic breeze whooshing against my door. I imagine the biting wind flowing through my veins, breathing life into my limbs, pushing me to be a part of the world beyond my warm, snug box. Once outside, the indoor fog in my mind lifts and my periphery expands initiating a new awareness. I enter the natural world to feel alive. Continue reading

Random Nature Questions from a Non-naturalist

by Audrey Clark

My stepbrother lounged in front of the television watching a reality TV show about mining in Alaska.  I sat on the couch, facing away from the television, drinking tea and reading a book on visionary scientists.

After a while, I started to wonder what my stepbrother wondered about.

“Caleb?”

“Yeah.”

“What questions do you have about nature?”

Silence.

Then, in an outpouring I wouldn’t expect from a non-naturalist, let alone one who was watching TV:

“Can plants feel pain?  How does a woodpecker not get a concussion?  How do you tell how old a tree is without cutting it down?  How long does it take ants to build an ant hill?  Where does honey come from?  Like what part of the bee?  What’s the best way to survive a bear attack?  Can animals get sick from drinking bad water like we can?  Why do monkeys have better immune systems?”

In honor of my stepbrother, here are my best attempts at answering these questions: Continue reading

The Charisma of the Drab

Wandering down Boulevard Saint Germain near Notre Dame in Paris, I passed a store window filled with insect specimens on display. The stylish sign read Claude et Nature (Claude and Nature).

I veered into the store, astonished that such a place exists. A small stuffed bison (small for a bison, that is) stood in the center of the store, next to a case of fossils. On the right were black cases full of artfully arranged insect specimens. On the left were fossils, shells, stuffed birds, skulls (human and weasel, among others), and sea stars. All were perfectly preserved and arranged, and neatly labeled with the species name and country of origin.

I spent some time perusing the insects—they had an uncommon family of weevils!—then wandered into the fossil section, then back to the insects.

Other customers were in the store, buying up iridescent blue morpho butterflies, flashy rhinoceros beetles with horny ornamentations, and large walking stick insects, which look just like knobby sticks with legs. All of the creatures on sale were eye-catching in some way. I found myself disappointed that there weren’t more insects with mundane appearances. I craved some little drab ones so I could learn about their diversity. One of the most beautiful insects I’ve ever seen was brown and white and hardly bigger than a pinhead (a lacebug, in case you are curious). The insects present were in families already familiar to me.

This led me to ponder one of the differences between amateur and expert naturalists: level of attraction to charismatic megafauna.

Amateur naturalists and non-naturalists flock to the Serengeti to see lions and elephants, even just for a few hours. Few head to sandy beaches in Massachusetts to see tiger beetles. And when they buy preserved insects, they buy the largest, most colorful individuals. Experts and devoted amateurs, on the other hand, may be eager to see lions and tigers, but they are also there for the naked mole rats and dung beetles. Why?

I believe the answer has to do with memory and learning. An inherent characteristic of many animals is that they easily remember something bright, large, or dangerous. This is what is exploited by the wasp’s black and yellow warning coloration: remember me, don’t bother me, I sting. Young blue jays who eat a monarch butterfly and then vomit refuse to eat a second monarch because they recognize it. They may also refuse to eat other orange and black butterflies, whether or not those butterflies are actually noxious.

Just because I can easily remember what a blue morpho butterfly looks like doesn’t mean I’ll want a dead one hanging on my wall. A blue morpho is a beautiful blue that flashes sometimes deep sea blue, sometimes robin’s egg blue. I enjoy seeing beautiful things—that’s why I want it on my wall.

But I could just as well hang an iridescent blue hubcap on my wall; why a butterfly? Now my answer comes to the crux: because our love of living things is inherent.

This love is called biophilia, a term coined by E.O. Wilson and expounded upon by him and Stephen Kellert. This is why I find myself drawn to watch the fish in my aquarium and end up with a stupid, happy grin on my face. This is why people spend 30 Euros on a dead long-horned beetle (in spite of being dead, the beetle retains its living appearance when preserved).

I think experts have these three things—memory, appreciation of beauty, and biophilia—in larger or more finely tuned doses. Entomologists know and remember much more about insects than the average Schmoe, so they are more likely to remember the little drab ones as well as the big sexy beasts. They can notice more about a lacebug because they already know what it is. Their appreciation is honed to subtler beauty.

I have made it sound like being an expert is better than being an amateur in terms of seeing and loving the beauty of the world. Not so. Experts in the beauty of soil chemistry may be amateurs in the intricacies of maggot hibernation or cloud formation. They may not even see other parts of the world in any depth. Amateurs may be able to see and appreciate a broader slice of the world because they do not dig too deep a tunnel. I think there is a world between the loud blue morphos and the rare weevils where subtle beauty can be found and cherished.

On my last night in Paris I walked to Notre Dame, then across the Seine to the Hotel de Ville. There was an ice-skating rink set up in the square and a crowd of bundled Parisians whirling round and round. Some wobbled and held onto their equally wobbly friends, laughing and crashing into the wall around the rink. Others raced in weaving lines between the wobblers, or twirled on their blade tips in the center, muscular and graceful. The amateurs enjoyed laughing with their friends. For the experts, it may have been getting a move right. Both the amateurs and the experts were paying attention to the beauty of the experience, be it loud or subtle.

Happy Maggot Land

I came in to my cubicle at school last week to find a maggot squinching across my desk. After a moment of shock and disgust, I thought, “Ooh! What a nice present!”

You know you’re a naturalist when finding a maggot among your things makes you happy.

I’ve been collecting insects, so I naturally thought that one of my classmates left the plump grub for me to add to my collection. Surely it hadn’t come from the pile of soil samples I had on my desk, nor the cache of snacks I had in the cabinet. But yes, it had. I had collected a handful of red oak acorns and left them in an open plastic bag on my desk. Later, when I was working at my computer, I looked over and saw a pale yellow grub with a red face squinching around inside the slippery plastic among the acorns. I examined the nuts and discovered a hole in one of them, about 3 millimeters across.

That was when I got really excited. All I had to do was feed the little creatures and keep them happy, and I’d eventually find out what species they were. So I dug around in the faculty kitchen for a plastic takeout container, poked some holes in the lid with a pen, dumped my soil samples into it, and dropped the acorns and grubs on top. The grubs promptly burrowed out of sight. I labeled the whole thing with a permanent marker, “Happy Maggot Land, Please do not disturb.”

Then I started to worry about my maggots. What if the soil wasn’t enough to make them happy? Did they need something to eat?

I visited Jeff Hughes, the director of the Field Naturalist Program, who recommended I look in Tracks & Sign of Insects and Other Invertebrates, a recent book by Charley Eiseman, an alumnus of our program, and Noah Charney. I thumbed through and found the name of my maggots: long-snouted acorn weevils.

The female of this beetle species saws a hole in the shell of a red or white oak acorn and lays her eggs inside. The eggs hatch in a few days and the larvae eat the acorn meat. Beetles undergo metamorphosis like butterflies do; caterpillars are butterfly larvae, maggots are beetle or fly larvae. They molt five times inside the acorn and then leave their nutty shelter and burrow into the soil to pupate. Pupation in beetles is analogous to the caterpillar cocoon: a usually immobile stage of metamorphosis just before emergence as an adult. In the spring, adults emerge from the soil and fly off to mate before beginning the cycle again.

I have named my maggot friends Weevil Kneevil, Do No Weevil, and Axis of Weevil, but I have no intention of keeping them. I plan on releasing them back into the forest to continue to parasitize on oaks. It’s not because I don’t like oaks, but because I like ecology. These weevils create food for other species: one genus of ant lives inside acorns abandoned by weevils and eats the leftover meat. Squirrels eat acorns sometimes just for the grubs inside—that’s one reason why you might find partially eaten acorns.

Having maggots as pets helps me see more when I go outside. I see potential Happy Maggot Lands everywhere—inside plant stems and fruit, in dying tree trunks, and in the soil under my feet. A new way of knowing the world around me has opened up.

Searching for Squirrels, Finding the Night

Written by Rachel Garwin

A week ago, I joined my friend Teage (a Field Naturalist alum) and a group of his UVM students on an “owl prowl,” Teage’s own euphonic term for a night hike.  We gathered at the edge of Centennial Woods, where gauzy tufts of white pines and bare hardwood twigs strained the clear moonlight.  A wall of darkness met our eye-level gaze, while the raspy sounds of drying beech leaves in the understory added to a sense of disquiet.  The primary goal for the evening was to listen for flying squirrels and call them in.  Before we entered the darkness, however, we observed a requisite pre-night-hike ritual.

Since leaving a well-lit environment too soon for the darkened woods might lead to undesirable confrontations with tree trunks and branches, Teage informed us about night vision while our eyes adjusted.  Human eyes require 20-30 minutes to become accustomed to low light conditions.  Coincidentally, it finally gets dark about 30 minutes after the sun first sets.  The students oohed appreciatively at the revealed secret of the universe.

I considered Teage’s implication, reflecting on whether twilight length was consistent enough to provide a uniform selective pressure.  The period between sunset and full dark (termed “Civil Twilight”) varies with latitude and season, as it reflects the time the sun takes to drop 6° below the horizon.  On the same night, civil twilight in Burlington, VT, lasted 9 minutes longer than in Bogota, Colombia, a city near the equator.  Atmospheric conditions and local weather can also affect our perception of available light from the setting sun, which increases variability.  Pole-to-pole variation aside, the length of civil twilight appears consistent enough at low and middle latitudes to suggest the plausibility of the relationship (though it does not prove it).  What mechanisms would select for correctly timed physiological processes?  Perhaps some hairy, fanged predator was involved?

Suddenly, I heard Teage ask, “Rachel, do you have anything to add before we head into the woods?”

Bits and pieces of the night hikes I used to lead rushed to mind.  Out of the torrent, what would be most relevant to this group of students?  Our pupils dilate to accept more light, just like a camera aperture changes size.  Our eyes comprise not only lenses (e.g., the cornea) that focus light, but also a receptor structure (the retina), which translates received light into neural signals our brains can understand.  The retina, in turn, is made of two types of cells: rods and cones.  Rods are far more abundant (about 17 for every cone cell); however, the cones are concentrated in the center of the retina.  Responsible for receiving color and fine resolution, cone cells are better suited for working in high-light environments.  Rod cells cannot understand color, but they register exceptionally more light than cone cells.  The operational ranges of the two cells overlap to some degree; in true twilight, both cells help parse the dim picture before us.

Instead of a long-winded physiology lesson, I settled on a practical and safety-oriented piece of advice.  “If you’re having trouble finding the trail in the dark, try using your peripheral vision.  Your rod cells—the receptor cells that are really good at picking up light—are arranged on the periphery of your retina, so that part of your eye sees better in low light conditions.”  With that, we were off.

As the trail contoured the side of a hill, I followed it with my feet as much as with my eyes.  Hard packed dirt spotted with only a few fallen leaves firmly resisted my feet, whereas my wandering steps sunk into noisy leaf litter.  After a few quiet minutes, we angled from the trail and picked our way down the gentle slope.  Looking out of the bottom of my eyes—as if I wore tiny slivers of half-moon spectacles—proved the best technique for avoiding the tangle of hardy ferns and woody shrubs.  Teage motioned for us to stop; this would be our first attempt to call the flying squirrels.

I listened intently.  Wind gusted through the upper boughs of white pines and red maples.  Still-hanging, papery beech leaves rubbed together, sending bursts of unwarranted excitement running through my mind.  Sirens howled close-by.  One of Teage’s students fired up the iPod, and high-pitched “chip chip chip” alarm calls radiated into the night to serve as bait.  I cupped my hands around my ears to exclude the droning car engines circling the outskirts of the woods.  Still nothing.  Perhaps the squirrels’ huge eyes, dominated by rod cells, picked us out as we muddled through their habitat.

I relaxed my eyes and marveled at the increased input from my peripheral vision.  Intermediate wood ferns stood distinct from the ground; before, they had dissolved into the dimness.  It seemed we had been away from bright light long enough for rhodopsin, a photopigment in the rod cells, to build up.  Rhodopsin and other photopigments in the cone cells help increase light sensitivity within the receptor cells, though at different rates and degrees. Cone cells, which never develop the light sensitivity attained by rod cells, take only 5-7 minutes.  Rod cells, however, may need over 30-45 minutes to achieve full light sensitivity.  In the presence of too much light, these photosensitive compounds break down; enough time in dark conditions is thus needed for photopigments to build up to a functional level.

The flying squirrels proved reticent, so we walked through the underbrush back to the trail.  The undergrads hesitated less between steps, and they seemed to run into fewer obstacles.  After walking a circuit across Centennial Brook and back along the lower slope on the other side, we paused to make their eyes’ night adaption more explicit.  Crouched beneath a closed hemlock canopy, we covered our left eyes and stared at the flame of Teage’s lighter with our right ones.  I smiled, startled by the pervasiveness of the “Pirate Patch” myth.  As lore would have it, pirates did not wear eye patches to cover gaping eye sockets.  Instead, they kept one eye in darkness to allow them to see below and above deck without needing time for rhodopsin to develop.  While no historical evidence supports this story, the folks at MythBusters put their weight behind its plausibility and likely had a role in its propagation.

Teage flicked off the lighter, and we switched our “eye patch” to the light-blinded eye.  Most students commented they could see more precisely with their night-adapted eye than with the light-blinded one.  Removing my hand, I winked back and forth at the hemlock boughs above.  Sure enough, my left eye discerned individual twigs against the dark sky; my right eye saw only fuzzy dimness.  While not proof that Blackbeard covered one eye so he could rush up to a darkened deck from a lamp-lit cabin, our experience supported the possibility.

We emerged from beneath the dense hemlock canopy onto a grassy hillside, where moon-cast shadows danced at our sides.  No longer relying on peripheral vision, the students carelessly walked down the trail towards home.  I smiled.  An hour ago, they had hung together timidly in similar light levels, still uncomfortable with moderate darkness.  Now they practically ran.  While the flying squirrels had remained elusive, the students found something more powerful: the ability to stride confidently through the night.

Will You Need a Warmer Hat This Winter?

by Carly Brown

A few weeks ago I tied my laces, donned my hat, and set off for a long run down Spear Street, from Burlington to Charlotte and back again. Partway through my run I saw it crossing the road without any signs of hurry, proudly displaying its black and rusty fur: the woolly bear (Pyrrharctia isabella). I immediately looked up to check for oncoming traffic, then dodged out into the road, lunged, and swiped the fuzzy caterpillar. Without breaking stride I carefully set it on the roadside it was moseying to. Some feet down the road I repeated my behavior. My mind clicked back to middle school when I learned that a long rusty stripe means a mild winter. Is that true? And what are woolly bears when they are not cute, furry, caterpillars? Never mind what passing cars must think about my woolly bear lunge.

Wolly bear (Pyrrharctia isabella) caterpillar

Wolly bear caterpillar (courtesy IronChris, http://en.wikipedia.org/wiki/File:IC_Pyrrharctia_isabella_caterpillar.JPG)

The woolly bears that we see in the fall will overwinter as caterpillars under plant debris in the cold snow environment. In order to survive the winter chill, the caterpillars produce a substance, called a cryoprotectant, which acts much like antifreeze. When spring begins to show its face, the caterpillars emerge from the leaf litter, begin to eat new plant growth, and then form a pupa to eventually emerge as the Isabella tiger. This moth is a relatively nondescript yellow-brown moth with several darker spots on its wings. Woolly bears have two generations per year. This means that the newly emerged moth lays its eggs, which hatch to complete the cycle through woolly bear and moth in the summer. The eggs that these new moths lay will hatch into the woolly bears that overwinter.

Isabella tiger moth (Pyrrhartia isabella)

The Isabella tiger moth (Pyrrhartia isabella) (courtesy Steve Jurvetson; http://flickr.com/photos/44124348109@N01/501714313)

Do these fuzzy caterpillars tell us something about the winter to come? The legend is that the longer the rusty brown stripe on a woolly bear, the milder the winter. Conversely, a narrow rusty band predicts a harsher winter. There have been a few attempts to correlate the size of the stripe with winter conditions. One of the most well known studies was by biologist Charles Corran in the 1940s. For the first few years of his study, the prediction of the woolly bear was correct, but there was more than enough evidence to disprove the common myth in the years to follow. Some suggest that the length of the rusty stripe may actually tell us something about the harshness of the winter and spring that occurred the year before.

I know deep down that the woolly bear myth is just that—a myth. That doesn’t stop me from doing a few extra lunges to save a woolly bear or two and check out the length of the rusty stripe. Curious about what this winter will bring? I suggest that you join me in the woolly bear lunge.