April 23, 2015 at 5:36 am (plant-eating insects)
Tags: Antheraea polyphemus, Mayslake, Nikki Dahlin, polyphemus moth
by Carl Strang
Last week, Nikki Dahlin and I found a black plastic bag blown up against the base of a tree at Mayslake Forest Preserve. We were going to throw it away, but Nikki noticed something.
A polyphemus moth caterpillar had pupated against the bag. Normally its secretions would simply cement its wraparound dead leaf, but here the bag was attached as well.
A dilemma. I decided to compromise, cutting away and properly disposing of the bulk of the bag, but returning the bit of plastic with the cocoon to the ground, as shown in the photo. Technically that makes me a litterbug, but I intend to return periodically to check, and will remove the plastic when the moth is out.
Can’t help but wonder how far that bag with its dormant passenger was blown through the air before landing at Mayslake, a preview of the moth’s flying days to come.
April 21, 2015 at 5:57 am (insects (other), invertebrates (other), mammals, reptiles and amphibians)
Tags: amphibian trap, Dytiscus hybridus, grassland crayfish, Hydrophilus triangularis, marsh, Mayslake, muskrat, northern leopard frog, predaceous diving beetle, Procambarus acutus, Procambarus gracilis, water scavenger beetle, western chorus frog, white river crayfish
by Carl Strang
I set out some amphibian traps in Mayslake Forest Preserve’s stream corridor marsh to assess how the marsh has recovered from the drought of 2012 and another drying out in 2013.
This leopard frog still is dark from its recent emergence.
I have caught and released several of the large predaceous diving beetles, Dytiscus hybridus.
Similar in size, this water scavenger beetle, Hydrophilus triangularis, was an addition to the preserve species list.
The club-like end of the antenna separates the water scavenger beetles from the predaceous diving beetles, whose antennae are thread-like.
The identification of this juvenile crayfish is uncertain, but the slender pincers have me thinking White River crayfish, in the past the most common species in that marsh.
I caught only one magnificent adult White River crayfish against 10 or so juveniles, sign of a recovering population.
Meanwhile, the grassland crayfish have been opening up their tunnels around the peripheries of the wet areas.
Grassland crayfish mainly come out at night to forage on land. Sometimes these foragers become foragees.
The marsh’s muskrats regard the amphibian traps as suitable platforms for their territorial markings.
Through all of this, the marsh’s sounds have been dominated by the songs of western chorus frogs. They are so small that they can squeeze their way out of the traps.
April 20, 2015 at 5:47 am (birds)
Tags: American coot, blue-winged teal, Canada goose, mallard, marsh, Mayslake, muskrat
by Carl Strang
Mayslake Forest Preserve’s marshes have awakened as the thaw has come and the water slowly warms.
This mallard pair was more than ready, resting on a muskrat house in March with the ice still around them.
We are seeing two Canada goose nests on the preserve this year, as females are incubating atop muskrat houses.
One in the stream corridor marsh
Another in the parking lot marsh
Meanwhile, the migration season continues.
A few blue-winged teal have been stopping by the marsh. This duck has not yet nested at Mayslake.
Yet another case of a face-on bird’s markings accentuating the bill, possibly making it more intimidating in an agonistic face-off.
This coot spent a day in the parking lot marsh.
Soon the migration focus will shift to the woodlands, as the neotropical migrants are on their way.
April 14, 2015 at 5:49 am (birds, restoration)
Tags: controlled burn, great horned owl, Mayslake, nest, St. James Farm
by Carl Strang
The end of winter brings with it the prairie and savanna controlled burn season. Mayslake Forest Preserve got some of that attention, but it was more limited than the almost complete coverage of two years ago.
Only half of the north stream corridor prairie was burned, for instance.
A thread of fire reached into the edge of the stream corridor woodland and ignited the tall stump which I regarded as the most likely nest site for the great horned owls last year. It continued to smolder for days.
Several feet of one side burned away, showing that the cavity had been wide open and quite deep.
I don’t know if any owl eggshell fragments could be found in the former base of the cavity, but it’s a moot point now as they won’t be able to use this platform again.
It’s a moot point personally, too, as I will be retired next year and plan to shift my preserve monitoring to St. James Farm, a preserve closer to home.
April 13, 2015 at 5:38 am (botany)
Tags: Claytonia virginica, Danada, Parson's Grove, seasons, spring beauty, St. James Farm
by Carl Strang
In my idiosyncratic 6-season calendar, Late Winter begins March 1, and ends on the day that I see the first native wildflower blooming away from the warming influence of buildings. Last week that criterion was met when I saw a spring beauty flowering in Parson’s Grove at Danada Forest Preserve. This was a little earlier than usual, but we’ve had plenty of warm weather to date, so that is to be expected.
Spring beauty, though not this year’s first. Didn’t have a camera on me.
Yesterday many spring beauties were in bloom at St. James Farm as well.
April 8, 2015 at 5:52 am (birds)
Tags: Cooper's hawk, Danada, dark-eyed junco, Fermilab, great blue heron, Mayslake, ruby-crowned kinglet, sandhill crane
by Carl Strang
We have long been waiting for spring, and the seasonal transition at last is under way. Soon the snow birds will be heading back north.
Dark-eyed juncos have begun to sing and to chase each other.
The earliest migrants have begun to come through, or to pass over.
A flock of sandhill cranes flies over Mayslake Forest Preserve.
They hit a thermal, break formation and use its rising air to gain altitude.
Breeders have begun to arrive and set up shop.
Great blue herons at the Danada colony
A recent arrival at Mayslake Forest Preserve has the smaller birds nervous.
The Cooper’s hawk pauses in its patrol…
The next mini-stage of migrant birds has begun.
Ruby-crowned kinglet at Fermilab, Sunday
Soon I expect to reach my personal criterion for the arrival of spring and the end of winter.
April 7, 2015 at 5:52 am (singing insects, Sound Ideas)
Tags: broad-winged bush katydid, Scudderia pistillata, Scudderia texensis, Texas bush katydid
by Carl Strang
Our bush katydids, genus Scudderia, have some of the most interesting song variations of all our singing insects. They include two “counting” species, with increasing numbers of syllables over a sequence of songs. Often they have more than one song type, and this is true of today’s featured species, the Texas bush katydid S. texensis (back in the days of the Bush presidency I was fond of pointing out that there really was a Texas bush katydid).
Texas bush katydid
The following recording includes two of the 3 song types: single clicks, which I seldom have encountered in the Chicago region, and the characteristic dusk or nighttime song, a series of quick buzzes.
During the day this species produces a very fast, 3-syllable call which I render “dig-a-dig.” It is similar to the daytime song of the broad-winged bush katydid, but the latter has more syllables (sounds like 5, usually) and they are less distinct because they have a lisping quality.
April 6, 2015 at 5:57 am (singing insects)
Tags: Cassin's 17-year cicada, Linnaeus' periodical cicada, literature review, Magicicada cassini, Magicicada septendecim
by Carl Strang
This week’s literature focus is on a single paper, which looked at a significant aspect of periodical cicada biology.
The northern periodical cicada species, Linnaeus’s 17-year cicada on the left, Cassin’s 17-year cicada on the right
Karban, Richard. 2014. Transient habitats limit development time for periodical cicadas. Ecology 95:3-8. He studied septendecim and cassini (our two local species of Magicicada) in New York state. There are several hypotheses explaining why their development times are so long: Pleistocene historical influences (long life span buffered annual climate variation in glacial refuges), predator satiation (some early maturing individuals wait for slower ones to catch up, and long life spans facilitate this), low nutrition forces long development, and increased fecundity (17-year species have been shown to be more fecund than the more southern 13-year versions). Here he examined the possibility that habitat quality changes rapidly enough to put an upper limit on such advantages of long lifespans. Though past studies pointed to possible advantages of edge trees, here he compared weights of newly eclosed adults from edge vs. forest interiors, finding the former to be only slightly (4.9%) heavier in septendecim but no difference in cassini. He took density of emerging nymphs as an indication of habitat quality. Changes in study sites were significant between emergences, enough to limit any advantage of longer life. He commented on the Raccoon Grove study site in Will County, once one of the highest-density populations known, mentioning that they plummeted over just a couple sequential emergences, first because of Dutch elm disease killing host trees. Karban and Yang visited that site in 2007, hearing one chorus but finding no emergence holes or nymphal skins.
March 31, 2015 at 5:55 am (Sound Ideas)
Tags: Charlene Strang, Ted Strang
by Carl Strang
The wild world provides a wealth of potential metaphorical material that artists long have used to express their insights. Today’s recording is a song I wrote back in 1997 when I learned of the serious illness of a friend, Jim Niemeyer. Jim passed away a few months later. I share the song now, as the anniversaries of my parents’ deaths last April approach.
Ted and Chuckie Strang on their wedding day
Mom and Dad with their three grandchildren
March 30, 2015 at 5:41 am (mammals, paleontology, Prehistoric Life series)
Tags: Ardipithecus ramidus, Australopithecus, Clovis culture, Denisovan, evolution, human evolution, literature review, Neandertal, Pleistocene, Pliocene
by Carl Strang
Human. Photo by Linda Padera.
Kimbel, William H., et al. 2014. Ardipithecus ramidus and the evolution of the human cranial base. Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.1322639111 From a ScienceDaily article. The base of this skull of the 3.4-million-year-old species Ardipithecus ramidus places it in the Australopithecus-human line and separates it from chimpanzees and other apes. The shape features may reflect a change to a more upright posture, or the early reorganization of the brain. Earlier studies had indicated that Ardipithecus was arboreal but also could walk upright on the ground.
Ashton, N., et al. 2014. Hominin footprints from Early Pleistocene deposits at Happisburgh, UK. PLoS ONE 9(2): e88329. doi:10.1371/journal.pone.0088329 They describe footprints of hominins estimated to be 850,000 years old, in sediments of an age where flint tools have been found, and establishing the earliest evidence of hominins outside of Africa. A combination of pollen analysis and stratigraphy (e.g., the footprints are beneath glacial sediments) established the age.
Vernot, Benjamin, and Joshua M. Akey. 2014. Resurrecting surviving Neandertal lineages from modern human genomes. Science 343:1017-1021. Gibbons, Ann. 2014. Neandertals and moderns made imperfect mates. Science 343:471-472. The Gibbons article is a news review describing Vernot and Akey’s study, which showed that though Neandertals and modern humans interbred, there were costs to the hybridization. Only a small amount of Neandertal genetic material has persisted in Europeans and East Asians as a result, mainly genes connected with keratin function, and so affecting skin color, waterproofing, and resistance to cold, helping modern humans to survive in more northern latitudes. They looked at whole genomes of several hundred European and Asian people, and found that collectively they preserve about 20% of the Neanderthal genome (each individual has only 1-3%).
Huerta-Sánchez, Emilia, et al. 2014. Altitude adaptation in Tibetans caused by introgression of Denisovan-like DNA. Nature, DOI: 10.1038/nature13408 From a ScienceDaily article. They looked at the genetics of these high altitude dwellers, and found that the main adaptation that allows them to live in low oxygen without heart problems comes from a gene their ancestors got through the Denisovans. The individuals who first moved into the area had some in their number descended from a modern human-Denisovan cross, and those people had a selective advantage in that environment.
Rasmussen, Morten, et al. 2014. The genome of a Late Pleistocene human from a Clovis burial site in western Montana. Nature 506 (7487): 225. DOI: 10.1038/nature13025 They worked up the genome of the only skeleton ever found in association with Clovis tools, that of a boy less than 2 years old found in a burial. His family and relatives are found to be ancestral to all Native Americans, and connected to Asian ancestors. The boy shares about 1/3 of his genes with the Baikal boy whose genome was sequenced in 2013, with the rest coming from east Asians, that blend happening before emigrating across the Bering Sea land bridge. The Clovis culture developed after the people were established in the New World, well before the 12,600-year age of the newly sequenced genome.