“Annual” Cicadas

by Carl Strang

The late summer days are marked by the droning songs of cicadas in the genus Tibicen. Unlike the periodical cicadas, which appear at 17-year intervals, some of these emerge each year. They sing from concealed perches high up in trees, so we seldom see them alive. Here is one I found shortly after its emergence from the ground on a rainy day at Fullersburg in 2007.

Tibicen linnei live 1b

This is Linne’s cicada, Tibicen linnei. Its drone is a rapid vibrato, and it has a wide range of habitats, so you can find this common species just about anywhere there are trees. There are three other common cicadas in this group in northeast Illinois. The one with the song closest to linnei’s is the lyric cicada, Tibicen lyricen. The songs are so similar, in fact, that it took a couple seasons for me to realize this was more than just variation within a species. Here is a specimen of lyricen.

Tibicen lyricen 1b

Note that the narrow collar behind the head is black. In the other three local species it is green. T. lyricen also has larger areas of chocolate brown just behind the collar. Its song has an even more rapid vibrato than linnei’s, sounding to my ear like a buzz saw. Song length is different, too. The vibrato portions of linnei songs are 15 seconds long at most (of 29 songs I have timed, only one reached 15 seconds). T. lyricen songs can be more than a minute long; the shortest of 24 songs I timed was 18 seconds. Median song lengths for the two species were 9 and 24 seconds, respectively. The lyric cicada can reach huge densities along rivers, being the most abundant Tibicen along the Des Plaines River at Waterfall Glen Forest Preserve, for instance. They also occur around lakes such as those at Mayslake. Usually they are close to a body of water. Another abundant, wide ranging species is the dog day cicada, Tibicen canicularis.

Tibicen canicularis 1b

This one looks very similar to linnei; it is the smallest of the four species. Its song is a high-pitched tone, siren-like, the vibrations occurring so rapidly that there is no vibrato. Song length is short.

I have no photo of the fourth species, the scissor-grinder cicada, Tibicen pruinosa. Though widespread, its numbers always are much smaller than those of the others. I have yet to see one, alive or dead (the photographed specimens were collected dead on the ground by my DuPage Forest Preserve District naturalist colleague Leslie Bertram). The scissor-grinder is the largest of the four. Its song is very distinctive, consisting of long pulses, rising and falling at 1-2-second intervals.

These cicadas all sing in daylight, quieting after dark. The lyric cicada begins early, peaking its singing in the morning but continuing in smaller numbers into the afternoon and evening. Peaks for Linne’s and dog day cicadas are in the afternoon, but they continue to dusk, and a few may start early in the day. The scissor grinder peaks its singing in the late afternoon to dusk, but can be heard at mid-day, too.

For recordings of these cicadas’ songs, go to the Michigan cicada web site  or the Songs of Insects site.

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If you build it…

by Carl Strang

Our yards are habitats for wildlife. We have no choice in that. We can, however, influence what kinds of wildlife will visit us or live with us on the land. This is true even for a tiny yard like mine. Here are some examples from my prairie flowerbeds, which are approaching their peak now.

Prairie garden 26JL09 b

I have planted royal catchflies all out of proportion to their presence in our local prairies.

Royal catchfly b

As a result, I can count on regular visits from ruby-throated hummingbirds in July and August. Here is this year’s happy camper, photographed through the kitchen window.

Yard hummer 1b

I kind of like this impressionistic view of the same bird.

Yard hummer 2b

Red tubular flowers shout “hummingbird” to ecologists, and to the birds themselves. I wonder if royal catchfly flowers also have evolved the means to defeat nectar thieves.

Bombus bimaculatus yard b

This Bombus bimaculatus bumblebee behaved as though it were in one of those sticky-slow-motion nightmares. The hairs on the royal catchfly calyx either were affecting it chemically, or physically had grabbed it. It wasn’t struggling strongly, so I suspect the former. As far as I know, no bumblebee has a tongue long enough to reach the nectaries of this flower from the front. Bumblebees are known to pierce such flowers from the outside, getting nectar but bypassing the anthers, therefore not serving the plant’s need for cross pollination. Such nectar thievery could provide selective pressure favoring any adaptation in the plant that might prevent the would-be perps from being successful.

In any case, I have plenty of bimaculatus visiting my other flowers, and also a few Bombus griseocollis.

Bombus griseocollis yard b

A final species for this time is the monarch.

Monarch larva b

This half-grown caterpillar is doing well on one of my butterfly weed plants.

Progress on Bumblebees

by Carl Strang

Earlier I posted some background on bumblebees . I find that I made an error or two there, I since have found additional species at Mayslake Forest Preserve, and also some added web sites specific to Illinois bumblebees that have helped immensely. The total list for Mayslake at this point includes 5 species, and I showed a photo from Fullersburg Woods of a 6th, Bombus vagans, in that earlier post. There are 9 species total for Illinois, of which 2 are rare. (Here I am not counting the nest-parasite “cuckoo bumblebees,” of which there are 2, but which I have not yet encountered). To this point in the season, the most common species has been Bombus bimaculatus, both at Mayslake and in my garden at home. It has a yellow thorax except for a black dot on top, the first (basal) abdominal segment is yellow, the second segment is yellow in the center front edge but black on the ends and back edge. Otherwise the abdomen is black.

Bombus bimaculatus 2b

The patch of yellow on the second segment often is small and hidden by the wings, so care is needed to distinguish bimaculatus from another common species (though perhaps less common locally than I implied in that earlier post), Bombus impatiens. The main difference from bimaculatus is that the yellow on impatiens’ abdomen is confined to the first segment.

Bombus impatiens queen 2b

One correction I need to make to that earlier post is that the dead bumblebee I featured was not Bombus fervidus after all. That bee had a black basal abdominal segment, where in fervidus the first 4 segments all are yellow. I have found a few live members of the dead bee’s species at Mayslake.

Bombus auricomus 10b

This is Bombus auricomus, which is regarded as “uncommon” in Illinois. Here, the first segment is entirely black, segments 2 and 3 entirely yellow. The sides of the thorax are black, and as the next photo shows, there is a large black area in the center of the dorsal (top) thorax.

Bombus auricomus 2b

At Mayslake I have seen only a few of these, always in the same place, so I believe there is only one colony of them on the preserve. Compared to other bumblebees they are large and very active. Bombus fervidus is at Mayslake, too.

Bombus fervidus 3b

Here you can see that the basal segment also is yellow, as is the entire thorax except for a black band across the back between the wings. In that earlier post I mentioned the ecological significance of differences in tongue lengths among species. Get a load of the tongue length on that fervidus!

Bombus fervidus tongue b

The 5th Mayslake species to date is Bombus griseocollis.

Bombus griseocollis swamp milkweed 3b

In this one the forward edge of the second abdominal segment is orange, but the back edge is black. The color on the second segment extends closer to the edge than it did in bimaculatus.

Bombus vagans, which I have seen at Fullersburg but not yet at Mayslake, has the first two abdominal segments yellow all the way to the back edge.

Bombus vagans 1b

That leaves only one species of bumblebee which is said to be common in Illinois but which I have not yet observed: Bombus pensylvanicus (listed in some references as B. americanorum). That one is most similar to B. auricomus, but typically has the top rear part of the thorax black or orange, and the first abdominal segment has some yellow on its rear edge.

Here are some web references. For a really nice diagrammatic comparison of these color patterns you can download a pdf file called “Bumble Bees of Illinois and Missouri”. A site with additional identification and ecological information is the beespotter site.

More Mayslake Lepidoptera (and others)

by Carl Strang

A couple days ago I updated the dragonflies and damselflies I have been finding at Mayslake Forest Preserve in my first year there. Today I’ll continue with newly sighted butterflies and a moth. These include black swallowtails, both female

black swallowtail female b

and male.

Black swallowtail male b

I have not seen larvae, but there are plenty of Queen Anne’s lace and other members of the family Umbelliferae that are potential food plants. When I saw the following hairstreak, I made sure to get photos.

Banded hairstreak b

This proves to be a banded hairstreak. A year ago I was alerted by Forest Preserve District invertebrate biologist Tom Velat to watch for southern or oak hairstreaks. That alert was prompted by the following photo I took of that species at Fullersburg, which I failed to identify correctly.

Southern (oak) hairstreak b

The hairstreaks require a close study of patterns in the lines of dots beneath both wings, and the arrangement of colors in the corner of the hindwing. I have one moth to share this time, the reversed haploa.

Haploa reversa Reversed haploa b

Haploa is a genus of tiger moths. I’ll close with three insects of milkweeds. The first is a familiar butterfly, the monarch, here visiting a purple coneflower in Mayslake’s Historic Garden.

Monarch Echinacea b

Monarch caterpillars feed on the leaves of milkweeds, in the process sequestering defensive poisons which then protect the specialist insect from its own consumers. Other insects have solved the milkweeds’ chemical challenge, and gone on to advertise their own poisonous status with bright colors. Two species in this category which recently have appeared at Mayslake are the red milkweed beetle

Red milkweed beetle b

and the large milkweed bug.

Large milkweed bug b

I’m sure I have barely scratched the surface of Mayslake’s Lepidoptera.

More Mayslake Odonata

by Carl Strang

Some time has passed since I last updated dragonfly and damselfly appearances at Mayslake Forest Preserve, and a few more species have added themselves to the roster. I have seen several four-spotted skimmers.

4-spotted skimmer 2b

This species seems to be abundant in some years, scarce in others. According to reports I’m hearing, Mayslake is joined by many other northeast Illinois locations in having a good emergence year for 4-spots. The following meadowhawk was the first mature red male I have seen this year. He kept his face hidden, so I did not get his identity, but in nearly the same spot I saw a ruby meadowhawk a few days later.

Meadowhawk b

The meadowhawk sought flying insects, when as you can see there were a lot of red aphids for the picking, on the same perch. I also encountered a couple new spreadwing damselfly species. This emerald spreadwing, with its metallic green body, is not done justice by this photo.

Emerald spreadwing b

New not only to Mayslake’s list, but also to me (a “lifer” in birder parlance) was this lyre-tipped spreadwing.

Lyre-tipped spreadwing 3b

So far I have seen two of these in different parts of the preserve. I’ll finish this update with a photo of a female 12-spotted skimmer.

12-spot female b

I’ll be surprised if more species do not show up before the end of the season.

Summer Prairie Wildflowers

by Carl Strang

My groundwork for future phenology studies continues at Mayslake Forest Preserve as I record first flowering dates for summer blooming plants, with the greatest number now occurring in prairies and meadows. The first, wild bergamot, has a broad enough ecological range sometimes to grow in open woodlands, too.

Bergamot b

More confined to proper prairies is the yellow (also known as gray) coneflower.

Yellow coneflower b

One of my favorites is the plant from Mars, or so I think of its odd appearance, more commonly known as rattlesnake master.

Rattlesnake master 2b

Butterflies like it, too. Drier prairies are good places to find hoary vervain,

Hoary vervain b

while wetter prairies are home to its congener, blue vervain.

Blue vervain b

Those plants will be much more spectacular looking when they hit their flowering peak, but here I am focused on first blooms of the season. Whorled milkweed, with its linear leaves, has an unconventional look for a milkweed.

Whorled milkweed 1b

Butterfly weed, a milkweed lacking the milky looking sap, arrests the eye.

Butterfly weed 1b

It is protected by internal poisons. Another eye-catcher, the purple prairie clover, is less fortunate. Rabbits love it.

Purple prairie clover b

Towering above nearly all the other prairie species is the compass plant.

Compass plant 2b

Now for some more mints (bergamot was one): the slender mountain mint,

NL mountain mint 2b

the common mountain mint,

Virginia mountain mint b

and germander.

Germander b

The earliest sawtooth sunflower heads always seem to have these odd bits of green popping out of them.

Sawtooth sunflower b

We are late enough in the season that the blazing stars are beginning to bloom. First of these at Mayslake is the marsh blazing star.

Blazing star b

The season’s but half done. There’s much more to come.

Mayslake Bird News

by Carl Strang

Birds are quieting as summer passes. Nesting for most species is winding down. Eastern kingbirds continue to be vocal, with a pair active between 31st Street Woods and the mansion.

Eastern kingbird 15JLb

Summer is a time when nonbreeders, post-breeders, and products-of-breeders wander. One day a juvenile spotted sandpiper stopped by May’s Lake, and provided this pose.

Spotted sandpiper b

Earlier  I mentioned my interest in Mayslake’s chimney swifts. They have continued to fly above the mansion, but as I have come and gone I have not noticed birds entering the chimneys. Then, last week, I went to First Folio Theater’s  summer production of Macbeth. Having seen their magnificent stage setting, I was looking forward to it.

Macbeth stage 1b

In the early evening before the play began, I was passing the east end of the mansion and heard a loud chittering noise coming from this chimney.

Chimney 16JLb

It was the sound of nestling chimney swifts being fed. I watched the chimney for a time and found that, as in other birds, feedings become much more frequent early and late in the day. Parental visits were at 5-minute intervals at dusk, but at noon the spacing was more like 15 minutes, and half an hour in the middle of the afternoon. I saw no action around the artificial chimneys, but nesting swifts in those structures may have fledged their young earlier. I was amazed by how rapidly the parents entered the chimney. The bird arrived from the side rather than dropping down from above and, still at speed, flicked a wing and suddenly vanished into the chimney. The exit flight was only slightly slower.

Chimney swift exiting b

I had the camera focused on the chimney, and hit the shutter the instant I saw the bird coming out. As you can see, the bird got some distance between itself and the chimney in the time it took my finger and the camera to react. Here is the swift cropped and expanded from that photo.

Chimney swift exiting cropped

Over the weekend the nestlings fledged. Though I don’t have answers to my earlier questions, I am better informed for another attempt next year.

Summer Woodland Wildflowers

by Carl Strang

In summer the main wildflower action shifts to prairies and other open areas, but in recent weeks there have been plenty of species blooming in the savanna woodlands at Mayslake Forest Preserve. Tall agrimony plants have been flowering for a while, now.

Tall agrimony 1b

These small yellow flowers will produce burs to be dispersed by mammals that brush past and catch the burs’ hooks on their fur or clothing. Another species that disperses in the same way is enchanter’s nightshade.

Circaea 1b

Named for Circe of Greek mythology, Circaea is an annual that I also could have included in a weeds update because of its “weedy” life history strategy. I expect to be pulling many of its tiny burs off my shoelaces later in the season.

The flowers of Canada black snakeroot are so tiny that they are easy to miss.

Canada black snakeroot b

Also small are the flowers of white vervain, but they at least are in strings at the tops of relatively tall plants.

White vervain b

Speaking of tall, here is a more conspicuous bloomer common in a wide range of our woodlands.

Tall bellflower

Tall bellflower was the subject of a study published last year that interested me (Yang, Louie H. 2008. Pulses of dead periodical cicadas increase herbivory of American bellflowers. Ecology 89:1497-1502). Yang experimentally fertilized plants of this species with the bodies of periodical cicadas, and found that deer preferentially fed on treated plants. This was a new demonstration of how the cicadas’ abundant emergences  have a profound ecological impact.

The shorter blue-flowering plants of self heal occur in woodlands and in the open.

Self heal b

Incidentally, lowering my sights one day as I walked the slope between the friary and May’s Lake, I saw the following plant.

Ginkgo seedling 2b

Unless I am mistaken, this is a ginkgo seedling. The closest female ginkgo trees I know of are a half mile away, on Mayslake’s Peabody Mansion grounds, though there is a residential neighborhood just west of the friary that might have others. Their fruits are notoriously smelly to us, but apparently were acceptable as food to a bird.

Among the most recent flowers to appear are those of the nodding wild onion.

Nodding onion b

I’ll conclude with a couple of species that occur both in open woodlands and in prairies: Culver’s root

Culver's root b

and, most spectacular of the lot, Michigan lily.

Michigan lily 1b

These are few and scattered wherever they occur, so remember to enjoy them in place and resist the temptation to (illegally) pick them. Flowers generally are protected on all forest preserves.

Mammal Action

by Carl Strang

In summer there is less to report about mammal activities at Mayslake Forest Preserve. Mammals are better able to hide in the dense green growth, most avoid coming out in the heat of the day, and the hard soil registers footprints less clearly. There are exceptions to this rule, though. Cottontails have been visible in numbers that have increased substantially since nesting began.

Cottontail 15JLb

It is well that they are so prolific, given the heavy predation pressure they face through the entire year (I shared several examples last winter, for instance here ).

Squirrels are diurnal, so they remain visible on summer days though mainly early and late. Mulberries have ripened, and become a major food for the squirrels at this point in the season.

Squirrel mulberry b

Scats indicate that coyotes and raccoons also are heavy mulberry feeders, the former taking advantage of the large numbers of the berries that fall to the ground.

Mulberry b

Speaking of raccoons, here is one that stayed out a little late in the savanna one morning.

Raccoon 1b

Probably this small adult was a mother, prolonging her hunt for food with a growing set of cubs to nurse.

Footprints attest that deer are on the preserve, but they have been able to stay out of my sight. Here, hoofprints show clearly in an area of mowed tall grass.

Deer tracks grass b

Mammals again will play a bigger role in this blog as summer transitions to fall and winter.

Parade of Weeds Continues

by Carl Strang

It’s time to update the list of newly flowering weeds at Mayslake Forest Preserve, following the broad definition of non-natives, undesirables, and species which gain high reproductive rates and dispersal by trading off competitive ability and lifespan.

I’ll begin with a surprise. I was crossing a wooded area and looked down to see an orchid. But it turned out to be our only non-native orchid, the helleborine.

Helleborine orchid 1b

Thanks to the dense, competitive meadows and prairies I have, so far, found only one common mullein plant on the preserve.

Common mullein 2b

Chickory can tolerate some shade, and so has done better.

Chickory b

Thanks to the former residents of the friary, Mayslake has to be the oregano capital of the Forest Preserve District of DuPage County.

Oregano b

Not only is there a huge patch of this herb in the old friary garden, outliers have spread as far as the meadow west of the off-leash dog area. Last winter I wrote about the interesting dispersal mechanism for Queen Anne’s lace . Here it is in bloom.

QA lace 2b

So far there have been two sow thistle species flowering at Mayslake, the common sow thistle

Common sow thistle b

and spiny sow thistle.

Spiny sow thistle 2b

Vying for the honor of most beautiful tiny flower is the Deptford pink, relative of carnations.

Deptford pink b

The white sweet clover now is blooming abundantly, starting well after its yellow-flowered relative.

White sweet clover 1b

Common milkweed, weedy in its life history strategy but a native species, has been a bumblebee and butterfly magnet.

Common milkweed 1b

Another native, famed food of pop music’s “Poke Salad Annie,” is the pokeweed.

Pokeweed b

Once it’s this big, though, it’s poisonous. I’ll finish with a real undesirable, which I have been finding scattered around the preserve’s northern meadows.

Purple loosestrife 1b

Purple loosestrife can become a serious problem in wetlands.

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