Eliza Howell Nature Walk

In early July in Detroit’s Eliza Howell Park, Wild Bergamot begins to bloom. For nature watchers, it is an important and exciting time, a signal that the summer buterfly season is here.

As is evident from this recently taken photo, Wild Bergamot attracts a variety of other insects in addition to butterflies. My focus here, though, is on some of the butterfly species that I hope to see again this year.

The red spots of the Red-spotted Purple can be seen when the wings are closed.

Bergamot grows in clumps, about 3 – 4 feet tall. It is widespread in the wildflower meadow of the park, spreading by both rhizomes and seed, and blooming during most of July and August.

The small mark that gives the Question Mark its name is on the under side of the wing, not visible here.

Many gardeners grow a type of Bergamot, especially the red variety. It is often called Bee Balm and it attracts hummingbirds in addition to insects.

This week I saw the first Great Spangled Frittilary of the year in Eliza Howell — and it was visiting Bergamot. This photo is from last year.

Some of my insect-watching time is spent just standing next to a clump of Bergamot, noting the activity. A lovely insect might just come by, ignoring me as it seeks nectar.

Mourning Cloak is not very common in the summer, but when they do fly in the park in July, Wild Bergamot is one place they stop.

Tiger Swallowtail is more common in Eliza Howell. It makes the rounds of various flowers, one of which is Bergamot.

Photos can sometimes be misleading in terms of a the size of the subject. Comparing the insect to the size of rhe flower, one can see that a Silver-spotted Skipper is considerably smaller than a Tiger Swallowtail.

Wild Bergamot also attracts, at times, those fascinating daytime moths known as hummingbird moths. They hover at flowers, similar to the way hummingbirds behave.

As one can see from this series of photos, taken the last two summers, Wild Bergamot in bloom means it’s time to start hanging out in the wildflowers!

One of my annual projects is to make note of all the Bald-faced Hornet nests that I am able to spot in Eliza Howell Park (most years, about 10). I usually start seeing them in early September and continue to find more as leaves fall. They are large, but often placed in the thick of tree leaves, not visible until they are full size at the end of summer.

The nests are made of “paper,” wood chewed and mixed with saliva.

This is the first one found in 2021, in early September, visible only when one was almost directly underneath.

This year I have — finally — located a nest in the very early stage of construction.

Only mated female hornets (new queens) remain from last year. When a queen emerges from hibernation, she constructs a nest, lays eggs, and cares for the young workers, all on her own.

This nest, found on June 6, was probably the first stage, the initial construction. It was about three inches long. Since I had never seen an early-stage nest before, I watched until a hornet emerged so I could confirm the species.

If one knows where to stand and where to look, the nest is quite visible. Not only have I found the early-stage nest that I have been hoping for, but I should be able to watch what happens as the season progresses.

I have since stopped by almost daily. For more than a week, there were no noticeable changes, but by June 16, the entrance tunnel had been removed.

Almost every day since, there have been more changes. It looks as though the hornets are tearing apart the previous outer wall and making a new one, a little larger. In the process, some of the inner activity of the nest is visible with the use of binoculars

This is June 21

And this is June 24. Note the outer layer being constructed from the top down

By June 27, the bottom of the nest is beginning to look more closed, more like a small version of a full-size nest. At this point it is approximately softball size.

So, in three weeks, there has been a significant change in the size and some modification of the shape of the nest.

The hornets are actively and energetically engaged in increasing the numbers of new hornets (the queen’s role now is to lay the eggs; the workers construct the cells and care for the young). The workers are also continuously expanding the size of the nest to accommodate the growing population.

In two months, if all goes well, the nest will be home to hundreds of Bald-faced Hornets and will be, perhaps, over a foot long. This one, which I had cut down at the end of October last year and was showing to a group in April, shows how big they typically get.

This story is just beginning; it is only three weeks old. I am looking forward to see how the nest develops and what more I might learn about the behavior of these fascinating insects.

There will likely also be more to follow here.

In mid-June in Detroit, Summer meadow wildflowers are just beginning to bloom and butterflies are becoming active. Among the flowers now blooming, one is clearly attracting more butterflies than others: Red Clover.

Other flowers that are butterfly magnets — like Wild Bergamot, Purple Coneflower, Joe Pye Weed — usually start blooming in July. So, for now, I walk through Red Clover patches, phone camera in hand. (All photos here were taken in June, 2022, in the park.)

Red Clover, a native of Eurasia, was brought to North America centuries ago for agricultural purposes. It is used as a fodder crop and to improve the soil. It fixes nitrogen, a plant fertilizer.

Red Clover has long been naturalized here and bees, butterflies, and other insects are attracted to it for pollin and nectar.

“Butterfly season” in Eliza Howell Park, the weeks when they are most abundant, begins in July. Based on the number of species that I have already seen visiting Red Clover in June…

… it looks like 2022 might be a good butterfly year.

When I first spotted the large Snapping Turtle in the field during my walk in Eliza Howell Park this morning, I immediately suspected that it was on a mission to find warm friable earth for laying and burying eggs.

The Common Snapping Turtle has a carapace (upper shell) that is over a foot in length. It spends almost its entire life in water; the usual reason for traveling any distance from the river in June is to make a nest.

It stopped walking when I got close and withdrew its head.

I immediately left it to its mission, hoping I might find its nesting location when I returned later.

About 50 minutes later I returned to the area and was able to locate it. She (I now knew it was a female) was on some soft soil at the edge of a bench platform that had been installed this spring. She was obviously involved in laying eggs in the soil.

Over the next hour and 15 minutes I watched, at times from a distance and at times from much closer, as she labored to deposit eggs in the ground. Snapping Turtles lay about 20 – 40 ping-pong size eggs and cover them with soil. The warm soil is the incubator.

Being so occupied, she did not seem to mind when I got closer (I was quiet and made no sudden moves).

She could be anywhere from about 1 to 4 decades old; at about 10 years old, they reach maturity and they might live to about 40. As adults they have few threats apart from humans. And at this egg-laying time of the year, they are at risk of being hit by vehicles when crossing roads.

If all goes well, the eggs will hatch in about 80 – 90 days and the hatchlings will find their own way to the river.

After covering the eggs, she walked away, heading back to her life in the water. Her active mothering role is over — for this year

Later, after returning home, I did a little research and learned that the sex of the young turtles is determined by the temperature in the underground nest. At certain temperatures, all become female and at other temperatures, all become male. There is only a very narrow range where there will be some of each.

The mother’s task completed, the only signs of her morning mission are the spot of disturbed soil and the temporary track of pushed-over plants that marked her route.

The question now is how will the eggs / young fare. Contrary to the situation of adults, they are at great risk of predators. But the start looks good.

And again Eliza Howell Park was the scene of a new nature walk experience.

While most of my attention is focused on nesting birds prior to the June 11 Detroit Audubon field trip here, Eliza Howell Park is increasingly looking more like summer (that is, more evidence of meadow flowers and of insects).

Here are a few images from my walk in the park in the morning of June 8.

Hackberry Emperor (on the painted footbridge railing).

Ebony Jewelwing (damselfly).

Flowerfly nectaring on Coreopsis.

Early stage Bald-faced Hornet nest. (By September, this 3-inch-long nest will probably be about 15 inches long and 6 inches wide.)

Estern Tiger Swallowtail on red clover.

Yellow Goatsbeard in bloom.

Yellow Goatsbeard in seed.

Twelve-spotted Skimmer (dragonfly).

The weather is not always the best — and is certainly not the only — indication of the transition to summer.

The marvelous month of May has arrived in Eliza Howell Park and it is bringing out nature lovers. The forest floor is alive with small ephemeral flowers and some of the elusive colorful warblers are pausing briefly on their 3000-mile annual spring migration from Central America to the North Woods.

One of the marvels of May in the park is observed by very few people — the emergence of the year’s Praying Mantises. It happens quickly and the timing is weather-dependant, so not fully predictable. Someone in the right spot at the right time (probably late in May) can observe the fascinating phenomenon of a hundred or more young mantises crawling out of and away from an egg case in which they spent the last 8 months.

Scattered in the park, mostly near the meadow wildflower field, are a number of  egg cases (oothecae) of the Chinese Praying Mantis, attached to shrubs, limbs of small trees, flower stems, and vines, usually 1 to 4 feet from the ground. This photo is from this week.

Later this month, tiny new mantises will emerge en masse from the cases that survived the winter intact and healthy. Last year, a colleague and I witnessed  such events most clearly May 21 to May 23.

Praying Mantis young are very small. The egg case is usully only about an inch high and contains dozens to hundreds. Though tiny, they emerge fully developed, except that they lack wings. They head away immediately and begin to search for other insects to eat.

Praying Mantises do not survive the winter as adults. The new ones that energe in the spring die in the fall, after mating and egg laying. I usually don’t see them until some time in August, by which time they are fully grown and are preying upon the insects attracted to the summer flowers. The Chinese Praying Mantis is often over three inches long at maturity

After mating, females lay eggs (making the cases at the same time). In Eliza Howell, this usually occurs in September. This egg case was new when this picture was taken in mid September.

From September until May, through the long cold winter, the Praying Mantis population is contained in these insulated oothecae

By far the largest number of Praying Mantises in Eliza Howell Park are the Chinese species — and my observations above all apply to it. This year, though, we found a few cases that are distinct enough (and placed differently enough) to be a different species. It is probably European Praying Mantis, a little smaller species also found in Michigan.

As it gets warmer, we will try to keep an eye on these few cases as well. I have no experience with what they look like as the young emerge. With watching — and with sone luck — perhaps it will happen this year.

The weather has been cool this spring, so I do not expect mantis emergence within the next few days, but I hope I am there whenever it happens. It is a “Wow!” experience.