The Famous Woolly Bear – and Other Seasonal Caterpillars

On almost any extended walk in Eliza Howell Park at this time of the year, I come across caterpillars.

The best known moth caterpillar is also probably the most common in September: the Banded Woolly Bear (Isabella Tiger Moth caterpillar).

Woolly Bears are famous because their appearance in the Fall has long been used to try to predict the severity of the coming winter: the wider the middle rust-color band, the milder the winter, according to folklore.

They are now leaving the plants where they have been feeding and are on the move to find the right location to spend the winter. They remain in caterpillar form all winter long (surviving actual freezing) and go through the pulpa stage in the spring before emerging as adult moths. Isabella Tiger Moths are tan-colored and active at night; the caterpillar is much better known than the adult.

Here are a few seen recently.

There are other fuzzy moth caterpillars in EHP these days. In the collage below, the two on the left are, if I have correctly identified them, two differently colored Virginian Tiger Moth caterpillars. On the right is a Hickory Tussock Moth caterpillar

I am including no photos of the adult moths here, but I do have some photos of adult butterflies that can be paired with pictures of their caterpillars.

Most Monarchs had already migrated when this caterpillar (below) was still feeding on milkweed leaves recently. I do not know if it will be able to complete metamorphosis in time to fly south. The picture of the adult was taken earlier in the year.

Black Swallowtails are also common in Eliza Howell, though they are not as well-known as Monarchs. They lay their eggs on plants of the carrot family and I found this one in August on Queen Anne’s Lace (“wild carrot”).

Black Swallowtails are sexually dimorphic (differences in appearance between the sexes). The female is on the upper right; the male on the lower right.

I don’t know how many people would show up for an advertised “Caterpillar Walk,” but if someone wanted to offer one, September would be a good time. There are more varieties present than are included here.

Caterpillars can be viewed and admired even when it is not always easy to connect them with the adult moths or butterflies they will become.

Common Milkweed: A Frequent Stop

From May until October, Common milkweed is one of the flowers that I stop at regularly on my rounds in Eliza Howell Park. From being a “weed” in need of eradication, it has in recent years acquired both respectability and fame as a host plant for the larvae of the popular Monarch butterfly. I watch it for that role and for many other reasons.

In September, the plants, many of them 4 feet tall, are dominated by follicles (seed pods).

When the seed pods open – and some are just beginning to do so – we can witness the delicate beauty of the seeds attached to the silk that allows them to be dispersed by the wind. This is definitely worth seeking out a sunny fall day.

Common Milkweed is a perennial wildflower native to eastern North America that spreads both by seeds and by underground rhizomes, the second being the reason they are often found in patches. They sprout in May, usually shortly before the Monarchs return. (This year I saw the first Monarch on May 15.)

Monarchs start laying eggs on the milkweed leaves almost immediately after arrival. Once hatched, the larvae (caterpillars) eat the tender leaves. This picture of a tiny caterpillar is from early June.

By the end of June, milkweed is beginning to flower. I was especially struck this year by how fragrant the flowers are. Even for someone like me, who does not have the most sensitive nose, it is easy to know that one is in a patch of blooming milkweeds from the fragrance alone.

Milkweeds get their name from the fact that leaves and stems, when broken, produce a milky sap. There is a toxicity in the milkweed plant and Monarchs acquire this toxicity from ingesting the leaves as caterpillars. The result is that adult Monarchs are not preyed upon by birds, who have come to know that Monarchs are not healthy food.

Monarch butterflies are not the only insect that benefits from using Common Milkweed as a host plant for young. In September, it is easy to find seed pods covered with Large Milkweed Bugs. In the picture, the left shows adult Large Milkweed Bugs and the right picture is of young ones (nymphs). (Yes, there are Small Milkweed Bugs, but not in this entry.)

Large Milkweed Bugs have some characteristics similar to Monarchs: milkweed is the host plant on which the young feed; they are orange and black; they acquire a protective toxicity from milkweed; they migrate south for the winter.

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I have recognized Common Milkweed for as long as I can remember, but I have only really gotten to know it from my observations in Eliza Howell Park in recent years. The more I know about it, the more I like it.

 

Marvelous Monarch Morning

Monarch butterflies were active early on a recent late July warm and humid morning in Eliza Howell Park. I began to see them before 8 a.m.

Black-eyed Susan is now in bloom in the park. Based on past observations, it is not a flower I think of when I see Monarchs, so when a Monarch stopped on one to nectar, I approached for a picture.

Given the numbers of Monarchs flying in the peak of the summer flower season, I decided to record in pictures some of the different flowers Monarchs came to rest on this morning. The second flower was definitely no surprise; I have often seen Monarchs on Red Clover.

Monarchs are perhaps the best known North American butterfly – large, colorful, easy to spot, often discussed in terms of their migration practice and in terms of their declining numbers. One additional point is that Monarchs will often allow someone to get close while they are feeding on nectar, as long as the approach is slow and without any quick movements. These pictures were all taken with a phone camera.

Eliza Howell Park has several new benches. I was tempted to sit in the shade and watch the Monarchs, but I needed to be on my feet to get close.

Butterfly Weed is a Monarch favorite, a flower in the milkweed family that serves both a feeding plant for adults and a host plant for caterpillars.

Another flower that I have previously noted as a Monarch favorite is Purple Coneflower. One of the several Monarchs flying around in the “prairie wildflower field” stopped just long enough for a quick picture.

I cannot be sure, of course, because there were several butterflies in their irregular flight patterns, but I think that each of these pictures is of a different Monarch.

The last picture I took this morning is of the butterfly on Boneset. Boneset is not one of the more common flowers in Eliza Howell and not one that I have ever associated with Monarchs in the past.

Five pictures of Monarchs on five different flowers in about 2 hours = a Marvelous Monarch Morning.

I came away with a better knowledge of the flowers in the park that Monarchs select as food sources. After some 1300 Eliza Howell nature walks, I continue to learn something new almost every time.

 

The Lady Has a Favorite

Over the past two to three weeks, I have been noticing the amount of time the American Lady butterfly has been spending around and on Red Clover in Eliza Howell Park. The attraction is obviously very strong.

The American Lady, which is usually seen with its wings closed or only slightly open, has been present in large numbers this year. It is distinguished from the Painted Lady, in part, by the two large eyespots on the underwing.

Red Clover, with its pink flowers, is also abundant this year. It is a plant native to Europe and parts of Asia and Africa, which was brought to North America and has become naturalized here. It has often been grown as a fodder crop and is valued for its ability to enrich soil by fixing nitrogen.

This has been a great year for both Red Clover and American Lady in EHP. I suspect that the widespread clover is the primary reason there are so many American Ladies. The clover is, without a doubt, the Lady’s favorite flower.

The relationship between the two is not an exclusive one, of course. The clover welcomes other pollinators, not only bees, but other butterflies. I have seen visiting Red Admirals and Monarchs.

And the American Lady also likes to check out other flowers from time to time. Here it is on coreopsis.

It is fascinating to observe the American Lady’s strong preference for Red Clover, but I am left with a question: What was the American Lady’s favorite flower before Red Clover was introduced to North America?

Nature Discovery Day Is July 13

On Saturday, July 13,  there is a great opportunity for visitors to the park to become more familiar with the wildflowers, butterflies, birds, mammals, trees — and more – of Eliza Howell Park: 9:00 – noon. Free and open to everyone.

There will be exhibits, activities, and options of guided walks designed to point out some of the natural wealth of this Detroit park. The park entrance is on Fenkell east of Telegraph. The event also includes an opportunity to learn more about the U-M wildlife motion-activated camera project (which includes Eliza Howell Park).

Among the highlights of mid-July are the meadow/prairie wildflowers. Among those catching my attention recently are these.

Clockwise from top left: Foxglove Beardtongue, Black-eyed Susan, Butterfly Weed, Common Milkweed

The event is organized by Eliza Howell Park Partnership (EHPP), a coalition of persons with different organizational affiliations and a common interest in highlighting Eliza Howell as a place for observing and enjoying nature in an urban environment.

Guides will be present to assist in identifying the varieties of flowers, as well as the specific species of butterflies they attract. These are among the common butterflies at this time of the year.

Clockwise from top left: Monarch, Common Ringlet, Red Admiral, Pearl Crescent.

While I am often unable to get a picture of a butterfly I see, it is never difficult to find flowers waiting to be photographed.

Clockwise from top left: Staghorn Sumac, Chicory, Wild Bergamot, St John’s Wort.

Eliza Howell is the kind of nature park it is, in significant part, because the Rouge River runs through it. For those who wish to take it on Saturday, a short walk to the footbridge provides a good view of the shaded river.

Back in the field, one flower not to be missed is Wild Bergamot, a mint family flower, sometimes called beebalm, that has only recently begun its summer blooming season. It is a magnet for a variety of insects. In this picture, the visitor is a Hummingbird Moth.

Many mammals are more active at night than during the day. The cameras used in the UM wildlife camera project have located and identified some of the mammals of the night, as will be reported on July 13.

Two that I have recently seen during the day are White-tailed Deer and Groundhog.

I thank EHPP for providing this opportunity to witness and enjoy the natural wealth of the park.

 

An October Morning Walk: Today’s News

I arrived in Eliza Howell Park on October 9, 2018, at about 8:20 a.m. It was already warm, very warm for this time of the year, after a heavy dew. For the next three hours I walked about with my binoculars and phone camera, with frequent stops.

These are some of my observations on what is happening in the park today.

1.Sun and Dew

When the morning sun shines, it highlights the wet twigs and leaves, and the moisture rises in the air like fog. The temperature was unusual for October, but the picture is not.

2.Honeysuckle berries getting ripe.

There are many honeysuckle shrubs (Amur honeysuckle) in the park. They have lovely white flowers in the spring, but are perhaps even more attention-getting in the Fall. They keep their leaves longer than most deciduous plants and will be mostly green with abundant red berries into November. They have been ripening slowly and more are red every day.

3.Mushrooms continue in season.

I recently posted a report on some of the mushrooms in the park (October 4, 2018). Mushroom season continues and, in the last few days, there are even more to be found, in many shapes and sizes. This is just one of many I thought photo-worthy today.

4.Migrating sparrows arriving.

As I noted in another post (September 28, 2018), part of my October focus is on the variety of sparrows that pass through the park. This morning I saw six different sparrow species, including a flock of Dark-eyed Juncos and my first-of-the-season Field Sparrow (pictured here in a photo from another time).

Photo by Margaret Weber

5.Monarch butterflies are still present.

Monarchs have been in migration to Mexico for about a month now and I have been checking for them during each visit to the park to see whether there are any still present. Today I saw 4. So they have not yet all passed through, though that will happen soon.

I thought today of the Monarch caterpillar that I saw on September 12 (picture) and wondered then whether it would have time to make it to butterfly in time to head to Mexico with the others. Perhaps it is now on its way.

6.Chestnuts are falling.

Many, maybe most, of the nuts and acorns in Eliza Howell have already fallen. When mature chestnuts fall, the outside shell (the burr) opens on its own – to the benefit of squirrels and others. Many empty burrs are now on the ground under the trees. Sometimes the burrs open before they fall; this one is still on the tree, with two of the three nuts having dropped. (For more about EHP chestnuts, see post of July 31, 2018.)

7.Tree leaves are starting to turn.

Except for the species whose leaves turn red early (such as staghorn sumac and Virginia creeper), most of the leaves in the park are still green in early October. Today, however, there are definite signs that the change has begun on some of the large deciduous trees.

8.Second hornet nest found.

Bald-faced hornets often build nests in a number of trees scattered around the park. I typically see 10 or more each year, starting to spot them in late summer but finding most in the fall when they become more visible with the leaves thinning or gone. This year I had only seen one so far, a small one, found on August 17 and pictured here, and have begun to wonder whether this year might be atypical. Today I (finally) found a second one.

9.Purple love grass starting to tumble.

Anyone visiting the park in late summer or early fall is likely to notice the hue of the foot-high plants called purple love grass. When the grasses dry up, they (now brown) detach and blow across the ground like tumbleweed. Tumbling is now starting to happen. (The picture is from mid-September.)

10.Snails feeding on stems.

The terrestrial snails common in Eliza Howell (perhaps a type of banded snail) have been active since April, when they emerged from hibernation. They seem to be especially abundant right now, climbing up several feet on plant stems (they feed on both live and dead plants). Here is a collage of four I saw today.

These are some of my notes from a morning walk in the park.

 

2018 Butterflies: A Top 10 List

2018 has been a very good year for butterflies in Eliza Howell Park. Recently I saw the 30^th different species of the year (30 species that I was able to identify; there are some small brown skippers that I do not know well enough).

It was also a good butterfly year in that I was more successful in photographing them, learning to get close enough to capture them with a phone camera. The pictures here were all taken in the park this year.

This list could have been considerably longer, but these ten are the ones that I’d like to call to the reader’s attention at this time.

Common Buckeye (first seen September 11; photo September 11)

Though called “common,” I don’t see many Common Buckeyes in Eliza Howell. When I do see one, it is usually late in the season. They are a more southern species, at least for much of the season. In Michigan in football season it may be appropriate to point out that the “Buckeye” name has nothing to do with Ohio. 

Black Swallowtail (first seen May 29; photo September 7)

Male and female Black Swallowtails look a little different; this is a female. Black Swallowtails are common and are often found in gardens. Parsley family plants serve as food plants for the caterpillars.

Viceroy (first seen August 4; photo August 10)

Viceroy butterflies look like Monarch butterflies and benefit from the Monarch’s reputation among birds for being toxic. Ordinarily, Viceroys have a clear black band across the hindwings (a line which Monarchs do not have), but that line is extremely faint in this one.

Monarch (first seen May 24; photo August 6)

Monarchs are the most famous butterfly in country, known for their annual migration, their dependence on milkweed plants, and their recent decline in numbers. I don’t know the long-term implications, but there were a great number of Monarchs in southeast Michigan this year – and in Eliza Howell Park.

Tiger Swallowtail (first seen May 31; photo August 2)

Tiger Swallowtails were also common this year, showing up frequently throughout the summer.

Silver-spotted Skipper (first seen June 24; photo July 26)

Roughly one third of all butterfly species in North America are skippers and, as a rule, they are very difficult to identify. The Silver-spotted Skipper is the most easily recognized of the skippers, perhaps reason enough to like it.

Common Checkered-Skipper (first seen June 29; photo July 24)

The Common Checkered-Skipper, considered the most common and widespread skipper in North America, is also relatively easy to recognize. The males sometimes appear a little blue.

Giant Swallowtail (first seen July 17; photo July 17)

The Giant Swallowtail is fairly common in more southerly regions of the country, but not here. I feel fortunate any year that it shows up in Eliza Howell. Compared with many butterflies, it is indeed a giant.

American Lady (first seen May 31; photo July 14)

American Lady and Painted Lady are both found here; this year I saw American Lady a little more frequently. The Ladies, especially Painted Lady, migrate seasonally as Monarchs do.

Hackberry Emperor (first seen June 11; photo June 11)

I don’t know why a small family of butterflies is called “Emperor,” but the “Hackberry” name comes from the fact that the hackberry tree is the larval food plant. They are not common in Eliza Howell.

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In the middle of September, butterfly activity is slowing down and the Monarch migration to Mexico is well started. But there are still some butterflies around and it is not too late for a butterfly walk.  

 

 

 

Butterfly Weed: Photogenic for Five Months

From May through September, I frequently check the Butterfly Weeds in Eliza Howell Park, camera handy. There are three major reasons why it is one of my favorite wildflowers and one that “wants” me to take its picture often.

First, the color of the flower clusters is atypical as well as vibrant. The park is filled with yellow and white and purple flowers, but very few other orange ones.

Secondly, the flower is well-named. It is a magnet for butterflies, especially Monarchs. This year, I have found at least three Monarchs around and on the patch of Butterfly Weed pictured above every time I visited. Butterfly Weed is a member of the milkweed family, but Monarchs do not lay their eggs on it (they use only Common Milkweed). Butterfly Weed is for nectar.

Good nectar flowers attract other pollinating insects as well. The Bumblebee is just one of a variety of insects that lead me to pull out my camera, especially when the “bugs” are seen against the background of orange blossoms.

At this time of the summer, the beginning of August, most of the Butterfly Weed plants are transitioning from flowers to seed pods.

Soon, the Butterfly Weed will “want” to have its picture taken again. Usually in September, the seed pods mature and seeds begin to disperse. Butterfly Weed seeds are spread by the wind and they are fascinating as they prepare to float or fly away.

In the next picture, the seed pod is just beginning to open to let out the silk-winged seeds. In the following two, the seeds are (almost) ready to be taken away by the next breeze.

From its first bright orange flower to the silky seed dispersal, with a great many insects coming to it along the way, the Butterfly Weed has definitely won my full attention.

 

July Blooms and Butterflies: Part 2

In Part 1, I noted some of the most common wildflowers found in the park in mid-July. They will be there for the July 14 nature walk and the next time I go after that.

Butterflies, on the other hand, do not stay in one place. I am never entirely sure what I will see, though a few are seen almost every visit. Here are some often present in EHP in mid-July.

The first three can be considered large, as butterflies go.

Monarch

 

E. Black Swallowtail

 

E. Tiger Swallowtail

The next 6 are smaller, but not among the many very small butterflies. I characterize them as mid-size.

Clouded Sulfur   Photo by Margaret Weber

 

Red Admiral

 

Little Wood-satyr

 

Cabbage White

 

Silver-spotted Skipper

 

Common Wood-nymph

The last two pictured here are small. There are almost always additional small butterflies flittering around that I am not able to identify.

Banded Hairstreak

 

Crescent       Photo by Margaret Weber

It is very difficult to tell the different between Pearl Crescent and Northern Crescent. They are very similar. I think the one in the photo might be a Northern Crescent, but Pearl Crescent is more common in southern Michigan and more likely to be seen in EHP in the summer.

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I have always considered a day of seeing 6 or more different species of butterfly a very good butterfly day. On sunny days in July in Eliza Howell, there is often a very good butterfly day.

Monarchs and the Milkweed Advantage

Monarch butterflies are again active in Eliza Howell Park. Monarchs are among the most visible and common of the roughly two dozen butterfly species found in the park and one of the few butterfly species that migrate (they head to Mexico each Fall). They have returned. To be exact, it is not the same individuals that have returned (their lifespan is not that long). But Monarchs are back.

Photo by Margaret Weber

At the same time that I started seeing the first Monarchs of the year I began to notice that Common Milkweed, the wildflower that their life history is intimately connected with, have emerged and are growing rapidly.

Monarchs use milkweeds (mostly the Common Milkweed) as the exclusive host plant for their eggs and larvae. They will soon be beginning the process. Nature walkers will be checking the underside of milkweed leaves for the Monarch caterpillar, almost as easily identified as the adult butterfly.

Photo by Margaret Weber

Monarchs nectar on many different flowers (in the first picture above, it is on a butterfly bush), but its special relationship with milkweed in reproduction gives it what I think of as the “milkweed advantage.” There is a toxicity in all parts of the milkweed plant (ranchers/farmers are warned again letting their livestock graze it) and the Monarch acquires this toxicity from ingesting the leaves as caterpillars. The result is that adult Monarchs are not preyed upon by birds, who have come to know that Monarchs are not healthy food.

It is not a surprise that Monarchs like milkweed.

Photo by Margaret Weber

The Monarch is one of the best known and best liked butterflies in this part of the country and there has been a growing concern in recent years about the decline in their numbers. They continue in good numbers in Eliza Howell Park, perhaps in part due to the limited mowing that allows milkweeds to thrive. 

The milkweed flower is followed by the seed pods, which will ripen and open to silky seeds that are dispersed by wind. 

When I saw the first Monarchs last week, I immediately looked for milkweed. The two go together that closely. 

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Postscript: There is another insect that benefits from the toxic “milkweed advantage.” It is the brightly colored Milkweed Bug, found on the plants later in the year. That may be a story for another time.