Ripples 10/16/20

Posted on by October 21, 2020

Written by Jessica Johnsrud, Education Coordinator

Earlier this summer, I had the pleasure of leading a family twilight program. Two families participated in the program and it was the first time most of them had walked a trail in the dark, including the parents.
 
After a brief introduction, we started down the trail. The kids were buzzing with excitement and perhaps a little nervousness too. Any nearby animals were surely alerted to our presence. However, after a few minutes, everyone quieted down and started using their senses to take in the evening.
 
We stopped in the prairie and listened with our “deer ears,” by cupping our hands behind our ears. The kids were able to pick up faint cricket sounds as well as soft call notes of songbirds they weren’t able to hear before.
 
Being in an open space, our eyes naturally gravitated to the evening sky. One of the older boys found the Big Dipper and proudly pointed it out to the rest of the group. We stood for a few minutes, in awe of the great number of stars we could see. One child noted he doesn’t see as many stars at his house in town. One of the youngest boys and I both had the good fortune of seeing a shooting star. He was very excited because it was the first one he had seen.
 
We then turned down the trail and headed back in the woods. We noted how dark it was and how difficult it was to see anything, except for outlines of the trees. As we slowly walked along, feeling the ground through our shoes, one of the kids saw something glowing along the side of the trail. We all stopped to watch, and sure enough, there was something small, glowing in the plants.
 
Once everyone had a good look, I used a small flashlight to investigate. To my delight, it was a firefly larva! I gently picked it up and showed everyone the strange, armored-looking creature. I explained firefly eggs hatch into larva that live in the ground. They are carnivores, eating snails, worms and other small invertebrates. Adult fireflies are famous for their spectacular light shows, but the eggs and larva of some species also glow. This is possible through a chemical reaction called bioluminescence. I set the firefly larva back where it was found and as we continued on, we saw dozens of them scattered on the ground! What a treat!
 
Back at the Nature Center, I asked everyone to share something they learned or share their favorite part of the program. One child said, “I never knew firefly babies could glow!” Other highlights mentioned were the shooting star, the bright starry sky and the chance for each child to briefly lead the group in the dark. It was a night of many firsts and something I think we will all remember for quite some time. 


Ripples 10/8/20

Posted on by October 23, 2020
As October wanes, animals are faced with several choices.  Well, not really choices, because they are determined by biology photo of common eastern bumblebeehoned over millions of years.  
 
There are two types of dormancy in living things- prescriptive, in which an organism enters dormancy before conditions become too difficult for survival, and consequential, in which an organism enters dormancy after conditions become too difficult to survive under normal means.
 
On the asters along our driveway, some of the last blooms of the season, a few worker bumblebees forage on sunny days, along with some gynes, next year’s queens.  The worker’s days are few now- they won’t survive the winter.  The gynes, however, go through diapause, during which their life cycles are suspended. They will spend winter in an old rodent burrow waiting for spring.
 
There are fewer and fewer frogs now, where once they had been so abundant.  In the parking lot, a snapping turtle crawls determinedly toward a pond.  Both are seeking a place to undergo brumation, during which reptiles and amphibians experience lower body temperatures either on land or in the water.  Some frogs, such as tree frogs, wood frogs, chorus frogs, and spring peepers, either freeze or nearly freeze, their cells protected from bursting by glycogen which they draw from their livers.
 
Some animals hibernate, lowering their normally warm body temperature to temperatures which allow them to burn less fat and sleep right through winter. Bears and ground squirrels are hibernators. Others partially hibernate – lowering body temperature but still eating occasionally, like chipmunks.  Even feisty little chickadees and other birds can lower their body temperatures at night and shiver throughout the day and night when it gets cold.  
 
Trees become dormant, although that is as much caused by the desiccation of dry winter air as it is from the cold.  
 
In addition to plants, other organisms such as bacteria and viruses have their own ways of going dormant- actually sometimes viruses cause bacteria to become dormant.
So creatures of all sizes have widely different methods for coping with the oncoming season.  That they are so different is remarkable and is a testament to their abilities to adapt to the many different scenarios which they must face.

 

photo- wikimedia

Ripples 10/1/20

Posted on by October 21, 2020

October.  The world is suddenly cool and colorful.  And alive with birds from the north passing through,  insects galore, and bursts of new wildflower blooms.  

I stole away one morning last week to walk a short loop on Willow Trail, one of the best areas in our preserve for migrating photo of wooly aphids on alder songbirds, to see what the previous night brought us. It was a partly cloudy and breezy day, but not too cold. The trail was lined with white and purple asters, the dogwoods still held their now mottled leaves, and the willows and cottonwoods were as green as  summer.  The poor ash trees, however, were dropping their yellowed leaves like snow flurries- they always seem to be the first to give up in the fall.  

In the wetter areas there were alder stems of various diameters, some of which had clusters of white fuzz.  It looked like they were moldy, but in fact they were supporting colonies of wooly alder aphids- small insects which huddle together and feed on alder sap. They are present through much of summer, but when leaves begin to drop they become more obvious to the casual hiker. In fact, their contrasting color and appearance can be at first glance gross and alarming, perhaps more than they need to be.   

Wooly alder aphids are fascinating bugs.  Their “wool” is actually a waxy substance which makes them look fuzzy and actually helps them to float on the breeze when they want to move to another plant. They need two host plants- silver maples on which to lay eggs and feed, and later alders. When on alders the females pop out clones of themselves without needing any sexual means of reproduction. At a certain point, males are needed, produced, and eggs are laid in a more conventional way.  When they are stressed, such as when freezing temperatures occur, they produce winged males and females who fly to the safety of a maple tree to lay eggs.  

The aphids feed on sap, both to obtain sugars and nitrogen with which they build proteins, and alders have a special relationship with bacteria which allows them to draw nitrogen from the atmosphere. The aphids must consume a lot of sap to get enough nitrogen, so much that they excrete some of the excess sap in the form of honeydew, a mixture of sugary juice and aphid poop. Other insects like ants feed on the honeydew and actually shepherd the aphids in little wooly flocks on the alders.  

The adult aphids probably die during the winter, but their eggs survive to ensure that another generation of wooly aphids, or fairy flies or fluff bugs as they’re sometimes called, will intrigue us next year. It’s almost guaranteed, as one researcher estimated, that if there were no predation or disturbance, a female could produce 6 billion offspring during the course of a year! There is predation to keep the aphid numbers under control, and they don’t do permanent damage to the trees.

Sometimes the smallest creatures are some of the most interesting, even if they are very different from us.

Photo – wooly aphids on an alder by Jim Knickelbine

Ripples 9/23/20

Posted on by September 25, 2020
photo of Swainson's thrush ready for banding

Swainson’s thrush

Although spring is widely anticipated as prime birding season, over the years I’ve really come to appreciate autumn.  At Woodland Dunes, our founder Bernie Brouchoud, spent many hours banding birds during fall, beginning with warblers in August and ending with saw-whets in late fall.  He banded something like 30,000 birds at our station over a period of 50 years spending countless hours and amassing tremendous knowledge of plumages and habits of our avian visitors.  Although I am licensed, I’m ashamed to say that I am only able to spend a fraction of the time Bernie did- the focus of my job pulling me constantly in other directions.  Still, there are mornings when I can steal away from my desk and attempt to band a few birds.  

It is hard to describe such days.  The mornings are often still and damp, and the call notes emanate from the shrubs all around.  If one gets out early one can hear the flight call notes from songbirds high above as they descend for the day to refuel and rest.  This happens just before sunrise, and it’s magical to hear the birds high above, then suddenly in the bushes all around.

Our banding operation is a small one, just a few mist nets set in a line.  After unfurling, we move a short distance away but within sight of the nets so that we can immediately retrieve any birds that are caught so they are in the nets for a very short time. They are immediately processed: banded, weighed, measured, and evaluated for fat reserves, and then released.  And yes, even if we have them in our hands, some warblers are tricky to identify in fall – males, females, juveniles- so a photo is often an invaluable aid to confirming identification later on.  The whole banding operation takes only a few minutes typically, but if there are several birds they are held in cloth bags for a short time. We do all we can to avoid stressing the birds. Between birds we sanitize our hands to avoid transmitting any disease.

Although banding is interesting, often the time spent waiting for birds is the most interesting, and relaxing.  Sitting outdoors, with warblers and grosbeaks, catbirds and thrushes and many other songbirds plus raptors migrating overhead is amazing.  Like any time spent quietly in a natural setting, it both centers us and reminds us of what really matters.  

Marking birds by banding allows us to track their travels and measure their lifespans.  It is a tool that allows us to further appreciate the miracles that are their lives, and remind us what we can do to ensure their survival. We need them in our lives more than ever.

Photo- a Swainson’s thrush ready for banding

Ripples 9/17/20

Posted on by September 17, 2020

Written by Nancy Nabak, Communication Coordinator

It’s fall so get out and take a walk on the wild side. I’m pretty sure you won’t regret it.

This is the time of year where the air smells earthy and the earth smells like your roots, your very origin. New subtle life forms are noticed and the tail end of what was once a happy blossom is begrudgingly fading into fallen petals. And the clouds also look different, carrying away summer’s wishes and ushering in romantic bonfire dreams of fall.

Last night was a good night for a fall walk. The leopard frogs continued to hold strong in their numbers and hop-ability. (It doesn’t matter what age you are, this year’s population thrust has to be bringing a smile to your face and reminding you of youthful days.)

Birds of all types are passing through now, new fall plants like bottle gentian are pushing up, and new fungus forms seem to be singing a different song. Sort of a sleepy, softer toned one, really. Preparing us for a slow down.

I’m a big fungus fan so my friend and I decided to go in search of as many as we could while on this stroll. We caught glimpses of new lichens, mosses and mushrooms, but we didn’t find the really captivating ones such as Lion’s mane, which looks like a white flowing waterfall, or the dead man’s fingers, which literally imitates gnarly fingers reaching from underground. But we did find a bluing bolette, a cream- to- yellow colored mushroom that immediately stains blue if scratched or cut. It’s really fascinating to watch this phenomenon. The center will go from a pretty yellow to a deep blue in seconds.

To our good fortune, the dimming light on the trail offered more than mushrooms, we also found a fat, second generation lime green caterpillar belonging to the striking Luna moth. It was impossible to miss and I kept thinking, “How is this not in trouble from predators?” Because it was so bold, I named it Spartacus. Spartacus had a brown head, a brown “x” on his back end, and yellow spiracles, little yellow dots which are actually external openings for respiration. This cool breathing process happens when it contracts its muscles to open and close the spiracles.

Unexpected moments in nature like Spartacus and bluing mushrooms steal my breath away. They give me pause to be grateful for all I have, and grateful that we live in an area where miracles like this are only a slow paced walk away.

Photos by Nancy Nabak