Nature Blog

Ripples 12/7/17

This article was written by Jessica Johnsrud, education coordinator. Photo (Red-tailed Hawk eating a mouse) taken by Nancy Nabak, communications coordinator.

Mice are the most abundant mammals in Wisconsin, so it’s no surprise many of us find evidence of their invasion in our homes. As the days get shorter and the weather turns colder, one may find mouse droppings or even hear the pitter-patter of scurrying feet in the walls or above the ceiling. 

photo of a Red-tailed hawk eating a mouse in the grass

Red-tailed hawk eating mouse

There are several kinds of mice in Wisconsin, but the species most likely to hole up (literally) in our houses for winter are the White-footed Mouse, Deer Mouse and House Mouse. All three species are common in the area and look very similar. They have large, naked ears that give them a keen sense of hearing. They also have bulging eyes and long whiskers that help them navigate at night, when they are most active. There is quite a variation in color from gray to light brown to reddish brown. Mice are small rodents, but the House Mouse is noticeably smaller at just 2.5-4 inches in length. 

Interestingly, not all mice are native to Wisconsin. The House Mouse was not known in the United States until around the time of the American Revolution when it’s believed to have arrived as a stowaway on transatlantic ships from Asia. The species is now found throughout the entire continent, but cannot tolerate winter. In regions with cold temperatures such as the Midwest, the House Mouse will seek refuge in houses, heated barns and other buildings. 

Mice are active year-round, even in the winter. They stay in their nest during the coldest winter days or during periods of heavy rain. Their nests are loosely constructed using dried grasses, mosses and other plant materials and have a hollow center. The center is made to be cozy for the mouse and is lined with soft items such milkweed seeds or animal hair. Outdoor nests can be found under or inside logs, inside standing dead trees or in small depressions in the ground. Once mice enter houses and buildings, they use insulation, paper and other human materials to make a nest in the walls or just about any nook or cranny. 

Many people are surprised to learn that mice are omnivorous and eat both plants and animals. They dine on seeds, fruits, nuts, insects, worms and even carrion (dead animals). In the fall, they cache away food until it is needed during the colder days of winter or when food is scarce. 

For most people, mice are unwelcome visitors inside our dwellings. However, they do serve an important role in the natural world. Mice are a very important food source for many animals including mink, weasels, owls, hawks, fox, coyote and some species of snakes. 

Ripples 11/30/17

This article was written by Jessica Johnsrud, education coordinator

photo of fruit bird feeders

Winter bird feeders

This year marks the 6th anniversary Woodland Dunes has been offering a Christmas Bird Count (CBC) for Kids. Children age eight and older are in invited to work with their peers in a small team, led by an adult bird mentor. Each group decides on a team name and goes through “Binocular Boot Camp.” This consists of gaining an understanding of where to look for birds, learning how to use binoculars, how to use field marks to identify a bird and how to use a field guide. After participating in these activities, each group heads outside to do the count. While surveying, they record the different species of birds encountered and how many of each they see. After, the teams sip on hot beverages and munch on snacks while compiling their data to present to the other teams. 

Younger siblings are also encouraged to attend the Budding Birders program, which runs simultaneously with the CBC for Kids. Children ages four to seven years will enjoy bird activities and participate in an abbreviated outdoor count with a bird mentor. The big event for these youngsters is making festive bird feeders using natural materials. Past favorites include smearing peanut butter on small wreaths and adding seeds and stringing berries and grapes on floral wire, which can be shaped into ornaments. The kids decorate the outdoor bird feeding area, named Chickadee Landing, and the birds sure seem to appreciate the gesture!

The Christmas Bird Count has an interesting history. It started in 1900 as an alternative to the popular “Christmas side hunts,” which involved shooting as many birds and wildlife as possible in one day. An ornithologist named Frank Chapman was concerned about conservation and the declining bird populations, so proposed a “Christmas Bird Census,” where people count birds rather than kill them. This was the beginning of Christmas Bird Count and this December marks its 118th year, making the count the longest-running citizen science bird project in the nation.

The CBC is conducted in the United States, Canada and several countries in the Western Hemisphere during a three-week period in mid-December through early January. The data from the count provides scientists with an idea of trends within bird populations. Anyone can participate in the count and you don’t need to be an expert. The counts are conducted in a 15-mile wide diameter circle within different counties on specific days. For more information about the counts and how to participate, contact Bob Domagalski, coordinator for Manitowoc County, at rcd2@new.rr.com. If you live outside of Manitowoc County, contact Kyle Lindemer, the CBC coordinator for Wisconsin at cbc@wsbirds.org. For more background information about the CBC, visit www.christmasbirdcount.org <http://www.christmasbirdcount.org> .

Please consider bringing your children to this fun program on Saturday, December 16th from 9:00-11:30am. The cost is $2 per child and registration is required by Friday, December 8th. To register or for more information, call 920-793-4007 or email jessicaj@woodlanddunes.org. We hope you can join us!

Photo taken by Jessica Johnsrud 

Ripples 11/22/17

This article was written by Jennifer Klein, land management coordinator and Jessica Johnsrud, education coordinator

Buck with large velvet antlers

photo taken by Nancy Nabak

It’s that time of year again. Folks are wearing blaze orange or blaze pink jackets, hats and pants. Turn on the radio and you may hear a man with a thick yooper accent sing, “have you seen da turdy pointer?” It’s deer hunting season and many hunters are talking about bagging a trophy buck with large antlers.
 
Bucks (male deer) grow antlers to attract females (does) and to fight off other bucks regarding territory or does. While growing, the antlers are covered in living tissue called velvet. The velvet supplies blood to the developing antlers through a network of veins, vessels and arteries. Late in the summer, the antlers will begin to calcify and harden. In September, the blood supply to the antlers is shut off and the velvet begins to dry and will eventually shed.

Antlers play an important role in the breeding success of bucks. The rut, or breeding season, begins in October and can last through December. Fueled by hormones, bucks use their antlers to fight vigorously, sometimes to the death, to show dominance and claim territory and does. 
 
During the rut, the antlers are anointed with the buck’s distinctive scent, a sort of cologne, through specialized skin glands located on the forehead. Bucks rub their antlers and forehead on the trunks of trees, leaving their scent and communicating to other bucks their dominance in the territory. Does smell and sometimes lick the rubs where the scent has been deposited in an attempt to find a strong mate.
 
The antlers are shed in the winter and will begin re-growing in early spring. Antlers are fast-growing and can increase as much as two inches per week!
 
Young bucks begin growing antlers within 5 to 6 months of age and are called “button bucks” because of the noticeable presence of two boney structures on the skull called pedicles. At 1-1/2 years of age (yearlings), males grow their first noticeable antlers, which can range in size from spikes to 10 or more antler points
 
As males mature, their antlers typically become heavier and better developed. On average, antler size increases until 5 to 6 years of age, when antler growth is maximized. Nutrition and genetics are also key factors into the size of a buck’s antlers.
 
So is there such a thing as a 30-point buck? You betcha! In 2009, a Wisconsin man took down a 30-point buck with a bow! 
 
Photo of buck taken by Nancy Nabak, Communication Coordinator

Ripples 11/16/17

Thanksgiving

On a November walk, the woods and waters of the Lakeshore seem so different.  The air is crisp and so are the leaves underfoot, and instead of a hundred bird songs there are much less – chickadees, some house sparrows, hairy woodpecker, and a red-tailed hawk- or was it?  At the end of the red-tail’s song there was a musical note – sure enough it’s a Blue jay doing an impression.  Farther along the trail is a very young eagle perched over the water- not a regal, white-headed bird, but a huge blotchy brown and white mass with an enormous hooked bill.  We watch each other, perhaps 100 feet apart, and as I slowly continue to approach, it lifts its tail and deposits a generous white mass into the water, as birds often do, before heaving itself into the air to fly across the water to a more comfortable perch.  I’m guessing this bird isn’t aware of the hype and majesty we humans assign to it as our national symbol.  Instead it lives in the moment – being the bird, the predator, and the scavenger it has successfully become.

photo of fallen oak leaf

Fallen oak leaf

Benjamin Franklin wrote some wonderfully sarcastic lines about the Bald Eagle’s lack of moral character- not befitting a national symbol.  He describes how the eagle sits perched at the water waiting to steal the hard-won fruits of the labors of the fish-hawk (I assume that’s an osprey).  Then he goes on to applaud the tenacity of the sparrow-sized kingbird which can drive an eagle away, or that of the turkey which, motivated by the bright color of the uniform, would drive a redcoat out of the barnyard.  I’m sure we wouldn’t fare too well if we relied on birds of any sort to lead us in battle, but we certainly do seem to like to conjure inspiring images where needed.

On the Great Seal of the United States the poor eagle is indeed spread-eagled in a very unnatural way.  With our national colors plastered on his chest, he or she holds arrows in one talon and an olive branch in the other- the capacity for war or peace I assume.  Olive trees aren’t native to America, but are important in the Mediterranean region and their branches were symbols of peace to Greeks (whose brides and virgins wore olive wreaths) and Romans (you brought them an olive branch when begging for peace), and certainly a good sign for Noah who had the double good fortune of receiving a dove carrying an olive branch.  There was also debate about whether the eagle should face the side with the arrows or the olive branch- it was finally decided that it should be the latter.  In reality, the closest native tree relatives to the olive we have here are the ashes, and the autumn and Russian olives we’ve brought from Europe are nasty invasives and we eliminate them as much as possible.

Instead of a national symbol, the poor turkey has instead been branded as either stupid or the image of bountiful consumption at the dinner table from a supine position on a platter.  Turkey hunters know they are far more than that- like any wild bird they are experts at knowing their surroundings and how to take advantage of them.  So the truth of turkeys seems to lie somewhere between that of Franklin or the table.

Nevertheless, November walks make one thankful for eagles, kingbirds, and turkeys equally I think.  And fallen leaves, resting trees, milkweed seeds and spruce trees.  November is a time to enjoy what may be our last snowless walks of the year, a time to reflect on how good the summer’s growth was, and a time to brace for things to come.  And people- we are so thankful for the many people here who still care about nature, and who help us as we try.  Nothing can warm us after a cold November walk than the people around us- and we need each other as much as we need nature itself.  

photo- a fallen red oak leaf


Ripples 11/9/17

photo of common buckthorn

common buckthorn with berries

Written by Jen Klein, Land Management Coordinator

I am among those who question every year why I live where there are four seasons.  Don’t get me wrong, I love watching the leaves change color, and even enjoy the snow.  However, it seems the negative always tries to creep to the surface, and the changing seasons first bring thoughts of cold temperatures and white knuckle driving in icy and snowy conditions.  Slowly, however, I acclimate myself to the temperature change, finding it easier every day to throw on that extra layer of clothes.  Then I remind myself of the beauty of the seasons, as well as the unique activities that can be enjoyed during each season.  Snow shoeing, apple picking, a fall hike, a day spent in the woods perhaps in a tree stand, all lend to being immersed in the natural world around us.  

Sometimes we get so focused on something that we forget to step back and look at the bigger picture.  One of my responsibilities as land manager at Woodland Dunes is controlling the many invasive species which threaten the native species.  Mostly we are looking at plants, such as Japanese barberry, various honeysuckle species, and common and glossy buckthorn.  While we know these plants can out-compete our native trees and shrubs, their impacts extend further than that.  I learned a few years ago that Japanese barberry creates a different micro-climate underneath it than what is present surrounding it.  This warmer and more humid space is favorable to the survival of mice, which are hosts for the ticks which carry lyme disease.  In this trickle down manner, the presence of Japanese barberry can lead to an increase in lyme disease cases.  Fortunately for Woodland Dunes, we also have healthy populations of fox, weasels, and other predators which keep the mouse population in check.  There are other indirect affects of invasive trees and shrubs and new ones are being discovered and researched everyday.

I was fortunate to attend the inaugural Southeast Wisconsin Conservation Summit recently.  This amazing gathering of individuals working within the natural world throughout Wisconsin provided the opportunity to network, share ideas, information, projects, and gain an understanding of things we may not have even thought about ourselves. 

I was familiar with the idea that buckthorn was bad for the plant community because it can overtake an area and actually emit a toxin into the soil which prevents other plants from growing around it.  However, I never thought about its impact beyond plants before attending the summit.  As I watched the leaves of other trees gracefully fall to the ground to create shelter for overwintering insects and provide future nutrients for emerging spring plants, I never thought about negative impacts of invasive species leaves.  Linh Nguyen, a student at Carroll University, presented information on the effects of buckthorn leaves and the survival rate of amphibians.  Buckthorn produces a metabolite called emodin which leaches out of the decaying leaves and is present in high concentrations in temporal ponds in the spring.  This kills tadpoles as their livers aren’t fully developed and cannot filter it.  Susan Lewis, also from Carroll University, presented research on the effects of buckthorn leaves on amphipods.  Amphipods are natures recyclers, shredding and decomposing leaf litter in waterbodies.  Her research showed that amphipods preferred to eat buckthorn leaves over ash tree leaves (the two dominate tree species in the study area).  However, the buckthorn diet lead to higher mortality and lower body mass.  

Examples like these remind us why it is good to step back once in a while and think about the whole picture. Fortunately, even if we are just removing invasive species because of its affect on the surrounding plant community, we are also benefiting the entire ecosystem in ways we aren’t even aware of.  This just makes our work even more important and re-energizes us to keep fighting the good fight.  
Jennifer Klein, CA®

photo- common buckthorn branch with berries