Nature Blog | Woodland Dunes Nature Center and Preserve

Ripples 4/20/2018

Posted on April 20, 2018 by Jim KnickelbineApril 20, 2018

This week’s Ripples was written by Anna Hall, Woodland Dunes Intern from Silver Lake College

Early this morning, I had the privilege of witnessing an American Woodcock searching for food in the front yard of the nature center. This is an uncommon sighting simply because woodcocks tend to spend the majority of their time hidden deep within fields and forests; they very seldom are seen out in the open. This woodcock was drawn out of his typical environment because of the large snowfall our area recently experienced, and he had to get creative about finding food.

American woodcock in snow

In order to feed, woodcocks require soft, exposed soil. They have a long bill which they use to probe into the ground in their search for little critters to eat. By far, this bird’s favorite meal is a healthy helping of earthworms.

Worms are high in both protein and fat, and comprise about three-quarters of the woodcock’s diet. One difficulty these birds may experience in their quest to find food is if after they have returned north in the spring, the area experiences late snow or the ground freezes solid.

When it comes time for the woodcock to breed, the males establish singing grounds. Their courtship dance is truly beautiful to see. The male will begin by emitting a buzzing sort of sound called peenting while he is on the ground. After a minute or so, he flies up into the air and hovers in a circle high above the ground. His descent pattern is quite interesting; after he is finished hovering, he will swoop down in a spiral as he sings a warbling call. When he comes to rest on the ground, he begins this dance all over again.

The female woodcock nests close to the singing ground where she mated. She is quite the independent lady, as the male plays no role in the nesting or rearing of the young woodcocks. The females favor nesting sites with plenty of ground cover and opportunities for camouflage. If the female woodcock is disturbed during the incubation period of the eggs, she may abandon the nest. However, the longer she stays on the eggs, the less likely she is to leave her unhatched babies.

All hatched birds can be categorized as either precocial or altricial. Precocial means they are relatively independent soon after hatching, and altricial means they require more extended care from their parents. Woodcocks are precocial; the young birds leave the nest just a few hours after hatching, and can successfully leave their mother after just six weeks.

As I continued to watch this woodcock prod the cold soil, I was struck by the beauty and intelligence of this deep forest creature. Its ingenuity and perseverance had me rooting for him to find some form of sustenance in the snow-covered ground. When he finally tugged an earthworm free, my hope that he would live to sky-dance and sing was renewed.

If you’re interested in seeing the woodcock’s courtship dance, join us for our Spring Twilight Trek at Woodland Dunes on April 27th (call for more info), or keep an eye out for this bird’s evening twirling at a forest edge or field near you.

photo taken by Nancy Nabak, Communication and Development Coordinator

Ripples 4/12/18

Posted on April 13, 2018 by Jessica JohnsrudApril 13, 2018

Sandhill Cranes are among the largest birds in Wisconsin, but imagine just how enormous they must appear through the eyes of a young child. Cranes are intriguing to watch and even though they don’t speak English, we can learn a lot about their communication by observing them.
photo of children preening like cranes Preschoolers preening like cranes

This month’s Raising a Wild Child preschool group learned all about Sandhill Crane behavior. The topic was a natural fit for April because the cranes are back from their wintering grounds and are easily spotted in open fields and wetlands.

Each child, aged two up to five years old, sat on a carpet square, which served as their “nest.” Next, thanks to YouTube, the kids watched short video clips of Sandhill Cranes displaying common behaviors. We briefly discussed each behavior and then acted them out.

We started by talking about how cranes move from place to place. They fly of course! The kids were enthralled with a video of two cranes soaring in the sky and singing their loud, rattling call. The call is so loud, it can be hard up to 2.5 miles away! We “cranes” stretched our wings and our necks and flew around the room for a bit, until we were ready to go back to our nests.

Next we learned about what Sandhills eat and how they groom their feathers. Cranes are omnivorous and use their long bill to probe the ground for seeds, tubers and fruits as well as small mammals, amphibians, insects and worms. The kids flew over to the field (open area in the room) and used their hand as a crane head. We walked around the field, eating mice, seeds and one girl exclaimed, “I just ate a salamander!” Once our bellies were full, we preened our feathers, using our hand as a beak to pick parasites off our backs and wings.

I think the kids most enjoyed learning about how cranes dance. They giggled when they watched a video of two cranes jumping, twirling and bobbing their heads. This display is part of the cranes’ courtship ritual, perhaps similar to human courtship! The kids flew to the field and wiggled, twirled and jumped up and down.

Many of the preschoolers also liked acting out how cranes defend their territory. They watched a clip showing a crane ruffling its feathers to an intruder, then the crane jumped up high and kicked its legs forward in powerful moved called a jump-rake. We flew over to the field and spread out so everyone had enough space. One of the parents pretended to be fox trying to steal eggs from our nests. We ruffled our wings at the fox as a warning, but she didn’t go away. Finally, we all jumped and kicked our legs out and the fox scurried off. Hooray!

By imitating the behavior of wild birds we hope to help children imagine what they are thinking, and in doing so learn to appreciate just how interesting they really are.

Photo by Brianna Trainor, showimg kids’ “preening” their imaginary feathers

Ripples 4/5/18

Posted on April 6, 2018 by Jim KnickelbineApril 6, 2018

For a week or so it actually looked like spring was coming, until the snow and ice descended once again. The robins and song sparrows and redwings are still out in the snowy yard, looking a bit forlorn but singing away nonetheless. And then there are the signs of spring from inside the building – scores of ladybugs crawling on the windows on sunny days. And the walls, the floor, all over the place. Good grief. Although they are members of the genus Harmonia, their abundant presence brings about anything but harmony. Rather, they usually result in the emergence of the vacuum cleaner.

Most old buildings serve as winter refuges for what are technically the multicolored Asian lady beetle, Harmonia axyridis,

Asian lady beetle

which are considered perhaps the most invasive insect on Earth. They are not one of our native lady beetles, of which there are many species that have lived harmlessly here for eons and are important components of our local ecosystems. The native lady beetles are smaller and are adapted to a particular ecological niche in the world. They tend to be predators of smaller insects, and are quite specialized in their roles in our forests and fields.

The multicolored Asian lady beetles, however, are large and apparently vary adaptable. They are indeed native to eastern Asia but have a large natural range from southern China north to Siberia and west to Mongolia. People have extended their range greatly either intentionally or unintentionally, and they are now found on at least four continents and across all of North America, where they were brought and released to control aphids in the South years ago. It was thought that they wouldn’t be able to tolerate the cold of our region, but as they say in Jurassic Park, “nature finds a way”.

The multicolored Asian lady beetles are active, aggressive, and seem to prefer meadow habitats in which to hunt their prey. They are good fliers, moving from plant to plant to look for all sorts of small insects to consume. They reproduce continuously, each female laying about 25 eggs per day during the warm months. The eggs hatch larvae which look like spiky dark caterpillars which also predate small insects, including eggs and other larvae of their own kind. Adults live about 30 to 60 days, except for those which hatch when the days become shorter – 10 to 13 hours of daylight, which induces diapause or a hold on their reproduction plus the urge to seek a sheltered place in which to spend the cold months. Old houses and buildings with cracks and openings offer perfect refuge, unfortunately.

Asian ladybugs have some other interesting traits that we notice when they enter our houses – they stink and they can bite. One of their defenses is to exude fluid from joints in their legs when they are alarmed. The fluid contains nasty smelling and tasting substances that deter predators. This odor is imparted into one’s vacuum when cleaning up the insects and becomes a permanent reminder of their seasonal visits to our houses. They also like to hang around vineyards, and if harvested with grapes can impart a bad taste to wine. Thankfully, most of them don’t bite, although their large mandibles can produce a surprising pinch. Rather, one occasionally seems to decide to taste us- one theory is that they have a taste for salt on our skin. Out of the hundreds I’ve encountered at the nature center and at home this winter, only one has decided to see how salty I taste, fortunately.

These insects have a lot of common names – including the harlequin beetle and Halloween beetle because they like to come indoors in late fall. They are extremely variable in appearance- sporting a wide variety of colors and color patterns from orange spotted with black to no spots to black spotted with orange. Almost all have white cheeks, patches on the sides of their thorax, or, second body segment. And although they are just a nuisance to us, they may be devastating to our native lady beetles, outcompeting and driving them out of existence. It is hard to imagine a ladybug as a bully, but like most invasive species that’s how they behave. And like many of the invasives, there will be no putting this genie back in it’s bottle- they are most likely here to stay unless a more potent bully comes along.

So do your best to caulk the openings in your house, and keep the vacuum handy. And, get used to the fact that you will always have lots of company at your windowsill on these first sunny days of spring.

photo- lady beetle from USDA

Ripples 3/29/18

Posted on March 27, 2018 by Jim KnickelbineMarch 27, 2018

Written by Jeni Klein, Land Management Coordinator

photo of tree with holes made by Pileated woodpecker

Pileated woodpecker holes

The other day Nancy Nabak and I were walking the Ice Age Trail in preparation for the upcoming Dash at the Dunes 5k trail run/walk on April 21. While we were measuring the trail, assessing areas that may need to blocked off due to spring melt, and taking notes on areas that may need course guidance, we came across a cedar tree with fresh holes in the trunk and wood shavings on the ground below. Upon further inspection, there were six more fresh holes on the other side of the tree, and three more trees in the immediate area with fresh holes. All of these holes were quite large. Some holes were round and some were more oval or rectangular. We were excited to find this treat: Pileated woodpecker holes.

Pileated woodpeckers are large in size, 16-19 inches long with a wingspan of 26-30 inches. For comparison, they are roughly the size of a crow. They have a red crest on their heads and black and white striping on their face. Males have a red stripe on their cheek. These birds hold large territories, mate for life, and do not migrate.

Pileated woodpecker

Pileated woodpeckers drill large, rectangular-shaped holes in trees to get to ants and other insects. These are not live, healthy trees; rather, they are trees which are either already dead, or are dying or have internal decay. These woodpeckers make their holesdeep into the trees as they follow tunnels made by opportunistic insects. They will then use their long tongues to reach these insects. They will also eat wild fruit and nuts such as hackberry, blackberry, sumac berries, dogwood, and elderberry. We have been planting many of these shrubs in our preserve over the past few years. Hopefully the woodpeckers and other birds appreciate the food we provide them as much as we appreciate the birds.

Pileated woodpeckers make large nest cavities which are occasionally shared with bats and swifts. Wood ducks, European starlings, and other woodpeckers also use dead trees for nest sites. It takes pileated woodpeckers 3-6 weeks to complete a nest cavity. They raise one set, or brood, of young a year, laying between 3-5 eggs. The incubation period is 15-18 days and the nesting period is 24-31 days, with young born naked and helpless.

Often we hear woodpeckers drumming on trees, creating these holes, but it is less often that we actually see them. The weather is warming up and spring in the air. Now is a great time to get out in the woods, and if you can sign up for our Dash on April 21, you can support Woodland Dunes at the same time. The spring ephemerals are starting to awaken on the forest floor, and you may just catch a glimpse of the Pileated woodpeckers.

photos by Nancy Nabak

Ripples 3/22/18

Posted on March 26, 2018 by Jim KnickelbineMarch 26, 2018

Years ago ospreys weren’t seen in our area. They, like other birds of prey, were susceptible to the insecticide DDT, which photo of osprey nesting platform going up caused their eggs to become brittle and easily broken. When I was young, ospreys and bald eagles were rare in Wisconsin. Fortunately, people cared enough about these animals to require that alternatives to DDT be used, and over the years the birds increased in population. Now, it’s not uncommon to see eagles here year round, and ospreys in the summer.

Ospreys seem to do well around Two Rivers, and have nested at Woodland Dunes for perhaps 20 years now. Last year there were two nests at the Dunes, plus others at Shoto, Mishicot, Manitowoc, Collins marsh, Kewaunee, and probably other places. One additional and particularly interesting spot was at Vietnam Veterans Park in Two Rivers- a popular place for baseball and softball games. At that park, which lacked a nest platform (ospreys had never nested there before) the birds several years ago decided to build a nest on light fixtures over the ballfields. While this is not an ideal situation, as there could be problems with heat from the lights as well as the possibility that the birds could drop branches onto the field below, the ospreys found a way to make things work and raised broods of young birds.

Baseball and softball are popular sports in Two Rivers and the facilities in the park needed to be updated, including the lighting for the fields. The Parks Dept. contacted Woodland Dunes last year to ask when the ospreys would migrate south so that they could plan for replacing lighting without disrupting the nesting birds, and indeed the lights were replaced in fall long after all the birds had left. However, their old nest had to come down with the old lights, and there was concern about what would happen when the birds return this spring. Neighborhood residents who had watched the birds in past years were also concerned that they would be displaced. Fortunately, the Two Rivers Parks Dept. was open to discussing the possibility of placing a separate nesting platform for the birds, and Steve Lankton, who is very interested in raptors, offered to donate the funds needed for the project. Moreover, Two Rivers Water and Light was willing to put up the pole and platform, which was built at Woodland Dunes.

Last week, on a sunny, cold morning, the pole and nest platform were installed. At this point, ospreys on their spring migration have already been seen as far north as Chicago, so this is being done just in time. Most importantly, I think this is a wonderful example of four different interests coming together to do something positive for wildlife with minimal effort or public expense. This reflects well on our community, and shows that we are willing to find ways to think beyond the ordinary, and give nature, in this case a formerly threatened bird, a chance to share our space.

That willingness is one of the reasons that this a great place to live.