Nature Blog

Ripples 5/28/20

photo of maple tree leaf blossomWritten by Jessica Johnsrud, Education Coordinator

After the gray of winter, the bright shades of green plants bursting through the soil is a welcome sight. Pops of purple, yellow and white flowers certainly catch the eye. We notice crocus, daffodils and tulips blooming in our gardens. In the preserve, marsh marigolds, trilliums, violets and many other wildflowers have started to emerge. Many trees are also in bloom in the spring and their flowers are actually quite beautiful. 

Currently, the red maples in my neighborhood are in bloom. In the spring, they produce tight buds that appear in clusters. As the temperature warms up, the buds swell and expose the blossoms inside. For a brief period of time, the trees are delicately flowered with red pom pom-like blooms before the leaves unfurl. 

Upon careful inspection, you may notice that the flowers look different from tree to tree or even from branch to branch on the same individual. Red maple trees are capable of producing all female flowers or all male flowers, a condition known as monoecious. However, a single tree can produce both male and female flowers and this is known as dioecious. I read that under the “proper conditions”, a red maple can sometimes switch from all male to all female flowers (and vice versa) and even from all male or all female flowers to having both flowers on the same tree. Red maples first bloom when they are about 8 years old, though that can vary greatly. 

The male flowers have long stamens that stretch beyond the petals. The tips of the stamens are covered in pollen. The female flowers have a stigma that extends past the petals and this has a sticky tip in order to catch the pollen from the male flowers. This is essential for pollination to occur. Red maples are mostly pollinated by the wind, but are also pollinated by native mason bees and other insects. 

Once pollination has occurred, the fertilized maple flowers will produce seeds called samaras. These are winged seeds commonly known as helicopters or whirlybirds because the wing makes them spin when they fall from the tree. The samaras are dispersed by the wind or by animals such as squirrels and will grow into new maple trees if conditions allow.

When the first leaves of the red maple unfurl, they are tiny and bright crimson. Eventually they grow larger, to almost 4 inches in length, and turn green. 

Many other trees are also in bloom including: paper birch, serviceberry, ash and black cherry. Each tree’s flowers reveal dainty blooms, some surprisingly fragrant. Don’t forget to look up to enjoy these easily forgotten blooms.

photo of red maple flower by Jessica Johnsrud

 

Ripples 5/21/20

I am guessing that many people are noticing nature more this spring than previous ones. I think that can happen when we are required to slow down. Over the last few weeks, I’ve been watching the paper birch tree in my front yard and I’ve been amazed at the variety of wildlife that visits it. 

I’ve mostly noticed feathered visitors. A few weeks ago, there were several kinglets flitting about high in the tree. I saw both ruby-crowned and golden-crowned kinglets and they were constantly moving to catch insects and spiders. 
photo of brown creeper climbing tree
Around the same time as the kinglets, I observed a brown creeper on the tree. This bird has a sweet little song and is interesting to watch forage for food. They use their beak to probe around the tree bark for insects and other invertebrates. As they look for food, they creep up the trunk of the tree, starting from the base and work their way up. Once near the top, they fly to the bottom of another trunk or back to the base of the same tree, to start over again. 

One morning, the tree seemed to be dripping with pine warblers and yellow-rumped warblers. Both species were busy looking for insects to eat, perhaps refueling after a long night of migrating. The yellow-rumped warbler can be identified by its name – it has a yellow rump which is noticeable when the bird flies. The palm warbler has a rusty cap and often bobs its tail. 

Woodpeckers don’t seem to visit the tree often. This is probably a good thing and may indicate the tree is fairly healthy and not infested with bugs. One day I did notice a downy woodpecker, but it quickly flew off to a different tree that had some dead limbs. 

Some of the more regular guests to the birch tree include chickadees, goldfinches, house finches and robins. I especially notice one robin in the early morning when I am enjoying my coffee. As the sun begins to rise (and even before), I hear his dawn song. This is a quick, continuous song that goes on for some time. If I step outside, there is an entire chorus of robins singing around the neighborhood. 

There have also been a couple of non-feathered visitors to the birch. I’ve seen a gray squirrel and a chipmunk both scurry up the tree when I open the door to go outside. The chipmunk scolds me, making high-pitched chipping noises as it runs away. Once in the safety of the tree, the chipmunk will stare at me and make repeated chucking sounds.  

A pair of Baltimore orioles were the most recent visitors. They had been feeding on my oriole feeder stocked with grape jelly and fresh oranges. What a treat to see this colorful sign of spring! 

I am sure there were many other visitors, especially invertebrates, to the birch tree over the last several weeks. It’s interesting how one tree can provide shelter and food for such an array of wildlife.

Attached photo is from the USF&W media library 

Ripples 5/14/20

Spring is a time when many people put their houses up for sale and begin to look for a different home. Many creatures are also seeking out the perfect location to build their homes and start a family. On my daily walks in the neighborhood, I’ve noticed a couple “for sale signs” by human houses and I’ve watched some of my more “wild” neighbors do some house hunting themselves. 

photo of a merlin perched on a branchNow that the ground is thawed, many robins have moved to the neighborhood. The males are territorial of their areas and will put up a fight if another crosses the invisible boundary. Sometimes these tussles carry on for a couple of minutes and can end with a few downy feathers floating in the air. Like many species, the female robin chooses her mate and the nesting location within his territory. Females favor more experienced males with the best singing voices. They usually have the best real estate and thus increase the likelihood that their offspring will succeed. 

A few pairs of cardinals also live in the area. I’ve watched one male lay on the romance by occasionally feeding the female. Perhaps this demonstrates his ability to be a good provider once she is incubating the eggs. They call back and forth as the female assesses potential nesting sites, the male tagging along. She will shop around before making the final decision on a nest site, typically a fork in a young tree or shrub that is hidden from view by leaves. 

Rabbits also live here, but I haven’t noticed them doing much house-hunting. I do usually find a nest in my yard at some point during the early summer. The female makes a nest in a depression in the grass that she lines with fur from her chest. It’s not a fancy home, but the young are well-camouflaged. 

I think we may have new neighbors on the block. They are a bit noisy and some of the other residents seem alarmed by their presence. A pair of merlins have been investigating the spruce and pine trees in the area. Merlins are feisty falcons and powerful fliers. I’ve watched them swoop into evergreen trees, then noisily call to each other. A couple of minutes later, one will hurriedly fly off to another tree and call to the other. I think they may be house-hunting and the real estate in my area is probably attractive to them. Merlins nest in abandoned great horned owl or crow nests that have a good view. They are in luck, because both crows and great horned owls live here and Lake Michigan is a block or two away. Once the site is selected, merlins will not do much remodeling (if any), before the female lays the eggs. 

The housing market seems to be strong in my neighborhood this spring. I look forward to watching new neighbors, wild and otherwise, move in and start raising their families. 

Photo from USFWS digital library 

Ripples 5/7/620

By Jessica Johnsrud, Woodland Dunes Education Coordinator

This sure is an exciting time of year! It seems like each day, a new plant is emerging, a different frog is singing or a new species photo of Black-throated green warbler in treeof migrant songbird has returned from its wintering grounds. In the last couple of days, I have seen my first black-throated green warbler, Nashville warbler and chimney swifts of the year. Other birdwatchers in the area have seen their first orioles, grosbeaks and even hummingbirds. These daily arrivals are little surprises and remind us that birds and nature aren’t in quarantine. 

Traditionally, Woodland Dunes hosts its annual Bird Breakfast and Migration Celebration in May. This event invites the community to a ham and pancake breakfast and celebrates the return of migratory birds through guided bird hikes and activities. This event also coincides with World Migratory Bird Day (WMBD), which is an awareness campaign highlighting the importance for conservation of migratory birds and their habitat. It also draws attention to the need for international cooperation to conserve migratory flyways because birds do not recognize borders. Each year, a theme is selected for WMBD and this year’s theme could not be more appropriate, “Birds Connect Our World.”

Birds do connect our world. The black-throated green warbler I mentioned earlier is a tiny, insect-eating bird that spent the winter in Central America. This spring, it flew thousands of miles through Central America, the southern United States, Wisconsin and is continuing it’s migration to the northern conifer forests where it will nest. This little bird will stop in forests and green spaces several times along the way to rest and refuel. Just think of all the people that may have observed the black-throated green warbler flitting about in trees and shrubs hunting insects? Or heard it’s distinct “trees, trees, murmuring trees” call? 

Birds also connect our world through scientific research. Scientists around the world use various tracking technologies to understand the routes migratory birds use, how long birds live and other health status information. Some scientists band birds with a metal band with a unique identification code, which helps identify the bird if it is recaptured again. Others use global positioning systems (GPS) tags by attaching a receiver to a bird, which receives signals from satellites that are orbiting the Earth. Data from these technologies is shared and used to inform international conservation efforts. 

There are several other methods of studying birds, but there’s one that everyone can take part in: sharing bird observations. People can record their bird observations online through eBird or iNaturalist or take part in citizen monitoring projects such as the Midwest Crane Count, Backyard Bird Count and several others. 

The Bird Breakfast event has been canceled this year due to the pandemic. Even though we can’t be together physically, Woodland Dunes is still celebrating Bird Breakfast and World Migratory Bird Day and invites you to do the same! Watch our Facebook page for posts about bird behavior, feeding birds, family activities and more! Posts will begin Sunday, May 10th and continue through the week. Birds truly connect our world and we can still connect virtually to share the common bond of birdwatching and caring for nature.

photo of Black-throated green warbler

Ripples 4/30/20

Written by Jessica Johnsrud, Education Coordinator

Field ants make their home in open areas, often with sandy, well-draining soil. They excavate tunnels, then carry out the soil with their mandibles (mouthparts) and deposit it at the entrance. Some species, like the ones I was observing, thatch the top of their nest with twigs and grasses, allowing the sun to heat the mound and warm the chambers and tunnels inside. The temperature inside the colony is important, especially for the development of the eggs and young in the nursery chambers. All the eggs are laid by the queen and most will hatch into sterile females workers. 

Ants, along with termites and many bees and wasps, are interesting insects because they are eusocial. This is the highest level of social organization and means they share a nest, cooperatively care for young and have overlapping generations within the colony. They also divide labor, with sterile members working for the benefit of a few fertile members. 

Some of the behaviors of eusocial ants are fascinating. For example, I read that some species of Formica tolerate multiple queens in the same colony. These species are able to grow into supercolonies containing millions of individuals living in mounds that spread over a large area. One Argentine ant colony in Westen Europe is thought to span 3,700 miles!

My research also revealed that some new Formica colonies are created through “temporary social parasitism.” This means a new queen leaves her birth colony, invades an existing ant colony (often of another species) and takes on the scent of that group. Ants communicate using chemical signals called pheromones. The invading queen kills the original queen and the worker ants will begin to care for the invader and her eggs. Once the new queen’s eggs hatch into workers, they take over the entire nest.

Ant colony behavior isn’t always so brutal. Some European species of Formica have been observed creating a raft with their bodies to escape flooding. Ants will also work cooperatively to carefully synchronize carrying heavy objects over long distances and even up vertical walls. 

There didn’t appear to be much drama among the ants I was watching. They seemed to be busy tidying up the top of the mound and likely looking for food. I am sure there was a lot of spring cleaning and preparation for the warmer season.

photo by Jessica Johnsrud