Species Dossier: Pied-billed Grebe

by Carl Strang

Grebes are cool. I love the way pied-billed grebes can sink without diving, and come to the surface with just the top of their head showing as they check out whether the coast is clear. They also have proven to have odd and unexpected evolutionary relationships. A recent study confirmed that the grebes are closest to the flamingos. Once you get your head around that one, add this result: among our local birds, the next closest relatives to the grebe-flamingos are the doves. Here are my observations on this species:

Grebe, Pied-billed

Pied-billed Grebe

Pied-billed Grebe

Common migrant on Maxinkuckee and ponds around Culver, generally appearing as individuals either isolated or on the fringes of duck or coot rafts. Breeder at McKee Marsh in DuPage County, IL. By mid-July the young were foraging with the parents, catching newly metamorphosed bullfrogs. Sings from water, a strange pumping song. “Ah-ah-ah…ah-ah-ah’dool-ah’dool-ah’dool…” The “ah” syllable increases in pitch untill it is very high when compared with the lower-pitched “dool” syllable.

4AP99. First of year seen, Culver.

10SE99. A single youngster spent a day on the Willowbrook marsh. This is the first one to stop at Willowbrook, perhaps because this was the first year with significant emergent vegetation along the edge. Still had some pied markings on the face.

30OC99. 3 on a lake at Fermilab.

8NO99. Lots of pied-billed grebes scattered among coot and duck rafts at Lake Maxinkuckee. Horned grebes outside, separate, and a few of the pied-billeds as well.

2AP00. One individual at Lincoln Marsh, Wheaton.

1JL00. An adult with at least 2 swimming small young, Brewster Creek marsh at Pratts Wayne F.P.

24SE00. Several migrants at McKee Marsh.

28OC09. Mayslake. A pied-billed grebe on May’s Lake swallowed a small fish.

23NO09. Mayslake. A dozen mallards diving for food in May’s Lake, coming up with aquatic vegetation after being completely under water 3-5 seconds. The grebe that has been staying close to them for a week still is present, and also diving.

5AP10. Mayslake. In the stream corridor marsh, 6 hooded mergansers and a pied-billed grebe diving for tiny prey, insect larvae and/or chorus frog tadpoles. Two of the mergansers were first-year males, with nearly white, indistinctly defined boundaries, in crests.

15OC. Mayslake. Two pied-billed grebes in the NW corner of May’s Lake. One flew when I came up on them, the other dove.

7SE12. Maylake. In the SE corner of May’s Lake, 25 mallards accompanied by a single immature pied-billed grebe that at times appeared to be dabbling.

 

Ruby-crowned Kinglet Dossier

by Carl Strang

Our two species of kinglets are early season migrants. Today’s featured species usually shows up a little later than the golden-crowned kinglet.

Kinglet, Ruby-crowned

Ruby-crowned kinglet

Ruby-crowned kinglet

I have seen this little northern-breeding bird in migrations, in northern IL and IN. Usually they travel in flocks. In 1986 they moved north later than golden-crowned kinglets, in mid-late April, mainly, in DuPage County.

26OC86. Single seen in brush at Willowbrook.

18AP87. First of year seen at Dunes State Park, IN. Has louder, harsher voice than golden-crowned. More chatter. Resembles goldfinch with a burr.

24AP87. Pratts Wayne Woods (Prairie Path). Moving from bush to bush. No vocalizations. Also, little or no probing; foraging by sight only.

21AP89. First migrants of year seen in the little park across from the Newberry Library, Chicago.

22AP89. Both kinglets at Willowbrook, using a mix of hover-gleaning and even more pursuit. Also, this is the kinglet with the song, high and thin, that has one section of accelerating notes flowing into a “chee-chee-per-chi-bee” section.

24AP89. Still at Willowbrook.

25AP89. Lots of them at Willowbrook today. First warm early morning of the year.

26AP89. A few present at Willowbrook.

3MY89. Still a few.

21OC89. Present in West DuPage Woods Forest Preserve.

17AP90. Observed at Willowbrook.

22AP90. Winfield Mounds. Has song “tsee-tsee-…(accelerating)…tsee-tsurd-tserber-tsee-tsurd-tserber-tsee.”

15OC90. Ruby-crowned kinglets at Willowbrook.

23SE91. IL Beach State Park. Kinglet in black oak, reaching, lunging, and very short-flight hover gleaning. 3-12″ per move, less than 0.5 second per perch.

12AP99. Willowbrook. Golden-crowned kinglets nearly gone (saw only 1), but ruby-crowneds have arrived.

20AP99. Ruby-crowneds are showing their red crests today (first time since they started arriving), defending little feeding areas along the stream at Willowbrook. Flycatching and flush-pursuit foraging.

21AP99. Today they still are foraging with much aerial pursuit, but are moving together in groups. No crests showing.

7MY99. A second major wave of ruby-crowned kinglets, probably females, at Willowbrook. None seen after this date that spring.

1&11OC99. Migrants at Willowbrook.

12AP00. Migrants at Willowbrook, singing occasionally.

16AP00. Willowbrook. Several ruby‑crowned kinglets on the preserve, some singing. Two observed showed much more flycatching than golden‑crowneds showed this spring, and some hover‑gleaning. Longer pauses on each perch while searching for an insect to pursue.

22AP00. Morton Arboretum. Both kinglets still present.

14OC00. The past week at Willowbrook, and today at Fermilab, ruby-crowneds foraging mainly in prairie areas with scattered shrubs, concentrating on the shrubs but occasionally visiting goldenrods as well. This open area foraging contrasts with their usual spring woodland preference. Golden-crowneds this fall have been sticking to the woodlands.

7AP01. A couple ruby-crowns seen among numerous golden-crowns at Greene Valley Forest Preserve. One of them occasionally sang.

20OC01. A kinglet foraging alone in a tall herbaceous patch (mainly goldenrods that have gone to seed) at McKee Marsh. I have seen several others behaving similarly the past couple of weeks. It flies from stalk to stalk, perching just below the seed/flower heads and looking all around, apparently for insects. Occasionally makes a hover-gleaning move, often against a seed head.

13OC02. An individual giving a quick, 2-noted call similar to chattering of house wren or perhaps yellowthroat.

9OC05. West DuPage Woods. Golden-crowned kinglets foraging in crowns of trees while ruby-crowneds are mainly within 4 feet of the ground in herbs and shrubs beneath, only occasionally and briefly venturing into the lower canopies. Ruby-crowneds have a quick, chattering-quality “checkit” call. Hover-gleaning their most common foraging method today.

5-11NO05. During my southern vacation, I found golden-crowned and ruby-crowned kinglets all the way to the Gulf of Mexico

23OC07. Fullersburg. A ruby-crowned flashed red in a brief squabble with another.

9AP13. Mayslake. A ruby-crowned kinglet was perched in place and chattering much like an irritated house wren.

Osprey Species Dossier

by Carl Strang

This dossier centers on a couple days from my kayak circumnavigation of Isle Royale, when weather compelled a 2-day stay at Hay Bay. It proved to be a highlight of the trip, and I learned most of what I know from experience of moose and ospreys during that stop. Otherwise, my knowledge of ospreys consists of limited snapshots of observations.

Osprey

Osprey

Osprey

I saw ospreys regularly over the Tippecanoe River, in Indiana, in summer in my childhood and early teens, but then they declined. By 1970, ospreys had become rare enough that a sighting in fall at Hawk Lake was remarkable. Then we saw some at Assateague Island, Virginia, occasionally carrying a large fish in their talons or catching one from the water’s surface. They had large nests of sticks there and on buoys in the Eastern Shore area of Maryland.

Osprey nest on buoy, Chesapeake Bay

Osprey nest on buoy, Chesapeake Bay

4SE88. Osprey flying south along the Fox River between North Aurora and Batavia, Illinois, at Red Oak Nature Center.

18AU96. Hay Bay, Isle Royale National Park. At around 12:30 an osprey appeared, coursing over the bay at 30-50 feet of altitude. After about 5 minutes it dove from more than 30 feet and plunged into the water, catching a good-sized, silvery looking fish (appeared to be about as long as the bird’s wing width). With much effort the bird flew up to the ridgetop across the bay. Between 3 and 3:30, two ospreys hunted over the bay, one started a dive but aborted, one after the other drifted over toward the bay entrance. They returned around 4:00, one perching on a tree and calling with loud, high-pitched chirps. The other aborted several dives and completed one in the 10 minutes I watched, but caught nothing. By 5:00, water had greatly calmed in Hay Bay. An osprey with a fish landed in trees back from shore, opposite me. A few minutes later one flew over the bay while another called. At 5:30 an osprey flew over camp with a fish. By then it was clear that there were 3 individuals, one possible youngster calling while the other two hunted. One successful catch, a larger fish, was carried out of view. Those plunges are dramatic, the birds highly specialized. Try to talk politics with an osprey, it’ll just say, “What’s that got to do with catching fish with your feet?”

After catching a fish, the osprey turns it around head first for easier handling in flight.

After catching a fish, the osprey turns it around head first for easier handling in flight.

19AU96. Hay Bay. Ospreys were hunting by 7:30 a.m. Their ker-plooshing plunges are audible at some distance. I saw an osprey catch a good-sized fish. “Kibitzing” calls increased from a bird on shore, but then it flew out and I saw that it had a fish, too. Both flew toward the ridge across the bay, but carried their fish up and over it. Around 11 a.m. an osprey hunted the bay for a good 20 minutes, with few dive attempts. It hovered in place 2-3 seconds a couple of times. On the third complete plunge, it caught a fish and flew with it in the same direction that the two went earlier. Much calling by another, perched bird during the first half of that hunt. 2:00 decisions, decisions: do I watch the moose feeding or the osprey hunting? The osprey dove close enough to me that I could see how it holds its feet up by its head. A miss. They always shake water off in mid-air, a few wing beats after clearing the surface. 3:00 There are at least 4 osprey, all at the bay now. 5:00 An osprey caught a good-sized fish (half its length), and carried it in the same direction, followed by another, fishless bird. Ripples only, still, in the bay.

16AP00. Willowbrook. An osprey flew over, SW to NE, with a fish in its talons possibly caught in one of the ponds at the College of DuPage campus.

19AP01. Willowbrook. An osprey flew over with a large goldfish in its talons. I’m not sure what direction it was coming from, possibly north.

2009. Tri-County (JPP) State Park. Ospreys nested atop the very high utility pole at the boundary of this park and Pratts Wayne Woods Forest Preserve.

Osprey nest, James Pate Philip State Park

Osprey nest, James Pate Philip State Park

2009-12. In most springs an osprey has spent some time (most of a week at times) at Mayslake, perching on trees at the edges of the lakes and occasionally fishing.

White-throated Sparrow Dossier

by Carl Strang

The white-throated sparrow is a common migrant and uncommon wintering bird in DuPage County, but it nests well north of here, so my observations are limited accordingly. Most of these notes were made before I knew there are dusky-colored adults, so some of the observations of “immature” birds no doubt were adults.

Sparrow, White-throated

White-throated sparrow

White-throated sparrow

This is a common migrant, observed around Culver, Lafayette, south central Pennsylvania, and DuPage County, Illinois. They occur in flocks, and forage on the ground in woods or old fields with at least some low brush. Often they scratch through litter. Their whistled song has been rendered “Old Sam Peabody, Peabody, Peabody.” The first two syllables are on the same higher pitch, the remaining ones on the same lower pitch.

6NO86. On dry leaf litter in dense brush in Willowbrook’s Back 40, one hopped along a straight course nearly upright, scanning the ground beneath and just ahead of it.

22AP87. First singing I have heard from this sparrow this spring.

27AP87. White-throated sparrows were foraging in the wooded riparian area at Willowbrook by kicking litter backwards with both feet while staying in place and looking down.

29AP87. Young sparrows were foraging up in shrubs and the lower branches of trees, making occasional “tseed” notes (high, thin, but fairly level in pitch). They used a probing-reaching-hopping foraging style.

1MY87. White-throateds are still abundant, adults using the in-place kicking technique on the ground. They also were hopping and looking (10-inch hops, pausing for 1-2 seconds). Two other adults on the ground and a youngster in the trees were probing, looking, hopping and walking among branches.

5MY87. Young birds were eating elm seeds (4 individuals doing so in the same treetop). They pulled seeds off with a sideways twist of the neck.

11MY87. There are still some white-throats around.

23SE87. First fall migrants in Willowbrook’s Back 40 riparian strip. Also observed SE25, 28, 30, and OC9, 11 (Pratts Wayne Woods), 13, 16.

4AP88. A number of white-throated sparrows have arrived in Willowbrook’s Back 40, but are only uttering high-pitched contact calls. A few were singing by 18AP.

13SE88. First fall appearance, Willowbrook Back 40.

21AP89. In the small park across from Newberry Library in Chicago, towhees, hermit thrushes and white-throated sparrows all were feeding out on the mowed lawn at noon like robins, the thrushes even with the run-and-pause.

2NO89. A few still at Willowbrook.

28AP99.  First white-throated sparrows of the season noted at Willowbrook. Also seen 5MY99 at McDowell Forest Preserve. Last seen this spring at Willowbrook 12MY, but only a few observed there this year.

13OC99. White-throated sparrows are much more abundant in fall than in spring at Willowbrook this year. One heard singing occasionally today.

26OC99. Willowbrook. White-throated sparrows are in the old field, brushy prairie area today (yesterday they were in the woods; today it is overcast, cold, calm; yesterday was clear, cool, breezy).

1NO99. At Willowbrook, sparrow eating dried gray dogwood berries.

18NO99. A sparrow eating Amur honeysuckle berries.

19JA00. Two white-throated sparrows at Willowbrook, on ground under dense brush, using the in-place kicking technique.

29-31AU01. Algonquin Park, Ontario. White-throated sparrows are in small groups, feeding on the ground and calling, once singing. Their behavior is the same as in migrants at Willowbrook, except that they are in smaller and very widely spread groups.

2FE04. Two at Waterfall Glen near Poverty Savanna, adult plumage.

24OC07. Fullersburg. I spshed out a sparrow that was giving the thin-ending call. It was a young white-throated sparrow, which immediately began emitting the “bink” call while turning in a rapid, jerking manner and turning its head quickly to look around. No other sparrows were calling in that area. (I have come to associate this “bink” contact call with young birds; certainly it is used much more often in the fall migration, seldom in the spring, when the thin whistled contact note predominates).

Lessons from Travels: Peat Soils

by Carl Strang

With November’s arrival, this blog shifts to its winter mode. I will be bringing in posts that share comments on the year’s scientific literature that are relevant to local natural history. There also will be more species dossiers. Of course, ongoing observations from the present season will continue to appear. Finally, there will be weekly episodes in the winter series. Past winter series have focused on science and spirituality (the Winter Campfire) and prehistoric life. This winter I will continue, and perhaps conclude, the Lessons from Travels series I began last year. The idea is to draw upon comparisons between northeastern Illinois and other parts of the world which cast a light on our local ecology and natural history.

A few years ago the Forest Preserve District of DuPage County collaborated with Chicago’s Field Museum of Natural History to conduct a paleontological dig at Pratts Wayne Woods Forest Preserve. Some mastodon molar teeth and bone fragments had been found at the site, and we brought in high school teachers and students to excavate parts of the site.

Here the digging began, 2007. Note the marsh in the background.

The dig went for two seasons. We mainly found fragments of the mastodon’s tusks. During the second year we uncovered some buried black spruce trees.

The stem of one of the trees runs the length of this trench.

The spruces were there when the mastodon died. That tree species no longer occurs in Illinois, though it is common in the North, where it retreated in the wake of the melting glacier. As we dug, we encountered buried soils that were familiar to me.

Buried peat soil.

This was exactly like soils we found when we dug into the permafrost in western Alaska, where I lived for several summers conducting my thesis research on glaucous gulls. Today there is much concern about the amount of carbon dioxide, and perhaps methane as well, that will be added to the atmosphere as climate change melts the permafrost. It seems that tundra fires will be major news in the future. At least then, maybe people will be able to bury their dead.

This scene, fitting with Halloween just past, is from an abandoned village site in western Alaska. The powerful churning of the surface soil as it thaws and freezes each year prevents burials.

We were not able to complete the mastodon dig. We suspect that the major bones remain beneath that marsh. The Field Museum withdrew from the project, and keeping even a small portion of the marsh pumped out for digging is more difficult and expensive than anyone wishes to pursue (though who knows, if we continue to have droughts like this past summer, it may become a practical possibility). For now the buried peat soils, the tree stems we left in place and covered, and the remainder of the mastodon, wait patiently as they have done for thousands of years.

Palm Warbler Species Dossier

by Carl Strang

Spring emphatically is here. Seasonal milestones are being passed earlier than usual this year. Migrant birds have been coming in, so far mainly the ones that winter in the southern U.S. Migrants that wintered in the tropics are not expected to appear much before they usually do, but among the first will be the palm warbler. Therefore it’s appropriate to conclude this winter’s series of species dossiers with that songbird.

Warbler, Palm

Palm warbler

This small warbler is a frequently observed migrant, both spring and fall, wherever I have lived in Indiana, Pennsylvania, and northeast Illinois. Usually they travel in small groups (2-6). Commonly they feed on the ground, but also forage in tree canopies. They are readily recognized by their distinctive tail-wagging behavior.

26AP87. North Blackwell Forest Preserve. The song can be rendered “witch-witch-witch-witch-witch-chyer-chyer-chyer-…chee.” Very rapid and chattering. An individual observed foraging alone 3-15 feet up in saplings with leaves beginning to open. It spent most of the time perched, turning its head to look every direction, staying at a given perch 3-10 seconds. Prey were obtained mostly through hover-gleaning, with sallies mostly of 2-5 feet out from watch perches. It sang every 10-20 seconds. It also probed into leaf clusters beside its perch once in a while, but more with a drinking motion.

29AP88. Pratts Wayne Forest Preserve. A palm warbler was flycatching in a leafless tree. It also searched, with 1-4-inch hops at 1-3-second intervals, in brush near the ground. Its song was a series of “jerv-jerv-jerv” notes, slightly juicy or buzzy, 4-6 quick syllables.

30AP89. McDowell Grove Forest Preserve. Some palm warblers were performing mid-air sallies (perches achieved at 5-10 second intervals between flights, and the birds did not return after making a grab but continued to a branch straight ahead, after flights of 7-15 feet). Others were foraging on the ground, hopping on paved or graveled areas. One sang a loud song: “Der-see’, der-see’, …” fast, the first syllable barely there, much emphasis on second syllable, ~10 syllables per song, many seconds between songs.

8MY89. Last bird of migration noted.

1OC89. Hidden Lake Forest Preserve. Palm warblers were in woods at a field edge, with white-throated sparrows.

25AP99. Palm warblers were at the Morton Arboretum in an area with pine warblers and chipping sparrows.

3MY99. A palm warbler was foraging 10-15 feet up in box elder at Willowbrook, the first of the year observed there.

5MY99. McDowell Forest Preserve, afternoon. There was little bird activity, generally, except for lots of palm warblers (and yellow-rumped warblers) feeding.

15MY99. A late bird seen at Red Oak Nature Center.

1MY00. A flock of palm warblers fed on the ground in the center of the cleared prairie at Willowbrook. Some also moved into scattered trees in the prairie area.

24SE00. A couple palm warblers were at the Sparrow Hedge, Fermilab.

20OC01. Blackwell, McKee Marsh. A palm warbler gave call notes similar to those of a yellow-rump.

12OC02. Several palm warblers were at Fermilab in old field areas.

28AP08. Fullersburg. A palm warbler was giving a call note similar to the distinctive one of the yellow-rump, though possibly higher in pitch.

Pratts Wayne Woods

by Carl Strang

Pratts Wayne Woods is the largest of DuPage County’s forest preserves. While its 3500 acres have much to offer, the target of my most recent visit was the Brewster Creek Marsh. I had a couple species of meadow katydids in mind that I especially hoped to find there. The part of that marsh I was surveying was adjacent to a dry area where there are high-level equestrian jumping competitions. As I passed through part of that meadow I heard a bush cricket’s short song. It took some minutes to find him, as he took advantage of the light wind moving his perch to keep an edge toward me.

His song was a little ambiguous. I have come to think of the broad-winged bush katydid’s short song as sounding blurred, run together, and composed of more than 3 syllables. The Texas bush katydid usually has a three-syllable short song that sounds, to my ear, crisp and articulated: dig-a-dig! I needed to take the time to find this individual because his short song had 3 syllables but sounded slurred together.

The wing proportions alone say Texas bush katydid, but to be sure I caught him and photographed his tail plate, confirming the ID. Now it seems I will have to find a few more and confirm that it’s the syllable count rather than the crispness that matters in separating these two species. Soon thereafter I found myself in a wet area dense with tall sedges in northern Brewster Creek Marsh.

It was disappointing, however. There was essentially nothing to be found out in the sedge area, and just a few black-legged and short-winged meadow katydids singing along the edge. I moved west to a grassy area at the edge of a large pond. As I stepped out of the woods into that grass I caught a flash of golden brown as a slender jumper got out of my way. My immediate hope was fulfilled when a close look proved the insect to be one of my target species, a male black-sided meadow katydid.

This was the best photo I got of a male. The abdomen is mainly a shiny black in color. I saw several males, and also a female.

She easily is the most colorful small meadow katydid I have seen, and would vie with the male black-leg (a large meadow katydid) as the local show winners for subfamily Conocephalinae.

Woodcock Dossier

by Carl Strang

 

After yesterday’s account of woodcocks at Mayslake, I thought I’d share my dossier  on that species. As always, I began with my observations of the species prior to setting up the dossier in 1987, then added observations coded by date:

 

Once I got a close look at one beside the Tippecanoe River. It walked slowly, with a peculiar bobbling gait, teetering on its short legs. Courtship display observed near Purdue in IN, in PA, and in DuPage County, IL. Male usually flies to his dancing ground in mid-late dusk, with distinctive mothlike flight (continuous flapping of round wings, with some curves and turns in course). Display begins with male on ground, emitting a flat, buzzing call, “beezt,” at 2-8-second intervals. A close observer hears a faint hiccup preceding (coupled to) this “peent” call. The bird turns occasionally to face in different directions. After several minutes of peenting the woodcock takes off, flying low with a whistling titter sound, then turning and flying upward in a spiraling or zigzagging climb. When the bird is near the apex of his flight he still is roughly over his ground site, and the whistling becomes more frantic and labored, in bursts rather than continuous. Finally he hovers or zigzags at an altitude of at least 300 feet, singing a beautiful plaintive whistling song with repeated phrases of separate notes going up in pitch, then down (usually 3 notes, with increasing emphasis, then 3 notes down with lower emphasis). Finally the bird becomes silent and zigzags steeply back to Earth, usually landing where he started, in a little arena of short grass within an early-shrub-stage old field near heavier brush. Often a bird will have 2-3 alternate ground sites. Began late March, ended by 1MY in northern IL, often extending later (even into June) in Indiana, e.g. at Hartz Lake. One bird was observed dealing with an intruder on 2 different nights at Pratts Wayne Woods Forest Preserve, in 1986. Intruder peented a couple times, resident made a loud long buzzing call, then flew toward the intruder, who took off. The pursuing bird escorted the intruder away the first time, but chased it closely for a long time the second night, eventually returning to his initial site. In NE IL the birds danced for around 45 minutes, going up 3-12 times during that period. As the season grew late, they went up fewer times.

12JL87. Flushed 2 in nearly dry artesian-well pond at Culver Fish Hatchery. Looked a little unsteady in flight: youngsters?

8AP89. No woodcocks flew at Pratts Wayne Woods (I heard 7-9 the previous week, and they flew for a program 4 days before that). Weather cold after a cold front, with snow. Also failed to fly 4 days later. Weather cold through that period. A couple peents each night, no more.

15AP89. Hartz Lake, IN. I approached 2 displaying woodcocks. One walked around a lot, over a 10-15 foot area, stretching up and walking slow or fast, between flights. Other walked only a little. First’s peenting frequency became very rapid once, when another woodcock flew over.

13MY89. Still going strong at Hartz Lake. After quitting in dark, one began peenting intermittently later (I was camping), well after dark, and even flew once, at ~11pm. No moon, dark with intermittent showers.

26-29MY90. Hartz Lake. Display still strong on 26th, with about 5 flights in evening. But number of flights tailed off daily. Both morning and evening displays. Morning pattern the reverse of evening’s. Only peented morning of 30th.

2JE90. Woodcock tracks in muddy rut of path at Pratts Wayne Woods. Interspersed with many beak-probe holes. Holes 1/8″ in diameter, sometimes soft mud produces a little larger hole. Middle toe 1.25-1.5″ long, side toes around 1-1.25″.

 

woodcock-track-drawing1

 

28FE00. 3 woodcocks peenting in north part of Warrenville Grove Forest Preserve. At least one did complete display at least once.

27MR00. As I ran the prairie path near the Northwoods subdivision at Timber Ridge Forest Preserve, I heard 2 peents from a marshy area at around 6:15pm, well before the light was dim enough for the usual beginning of the courtship display.

27AP06. Fullersburg. Woodcock probed in wet soil near edge of Salt Creek on Willow Island. Caught a large worm, pulled it out, cheeks bulged as it swallowed. Resumed probing after rocking from foot to foot several times. Later, when approached by a red-winged blackbird, it severely cocked its tail up beyond vertical. When the blackbird moved on the woodcock flew across the creek to a brushy area to the south.

Mastodon Camp

by Carl Strang

 

Over the past two summers I have had the opportunity to participate in a paleontological dig at Pratts Wayne Woods Forest Preserve in northwest DuPage County. This excavation, conducted by the Forest Preserve District of DuPage County and the Field Museum of Natural History, was prompted by the discovery of three mastodon molars and some bone pieces during wetland restoration work.

 

Photo courtesy Forest Preserve District of DuPage County

Photo courtesy Forest Preserve District of DuPage County

 

The dig is being structured as an education opportunity for area residents. Teachers and high school students have been the core participants in the first two years. There have been tours, presentations and half-day dig opportunities for members of the general public.

 

mc-day-8-15b

 

During the first summer, the main products were large numbers of small tusk and bone fragments.

 

mc-chunk-otusk-2b

 

In 2008 the digging revealed some small buried trees.

 

mc-day-11-9b

 

Wood samples are being analyzed, but two black spruce cones were found among the trees.

 

mc-day-9-3b

 

As I mentioned in my account of last fall’s glacier retracing trip, that tree species no longer grows this far south, but was here in this mastodon’s time 11,500 or 12,000 years ago. These paleobotanical discoveries fill in some of the picture of the local environment as local climate warmed after the glacier melted away.

 

With the major bones still waiting to be found, there is plenty of motivation to resume the dig when circumstances permit.

Rookery Trees

by Carl Strang

 

The great blue heron was the bird that first inspired my interest in learning about nature when I was a 7-year-old, watching several of them in a small lake one calm summer evening. A few years later a number of great blue herons established a new nesting colony near my hometown of Culver, Indiana, among the large branches of a grove of sycamore trees  in a swampy woodland.

 

great-blue-heron-closeup-b4

 

An interesting development over the past decade has been the proliferation of great blue heron rookeries in DuPage County. One on Danada Forest Preserve near the center of the county had 25 nests or so by 2001. Another large colony has been growing for several years at Pratts Wayne Woods. Close to there, at James Pate Phillips (Tri-County) State Park, an offshoot of the Pratts Wayne rookery existed for a few years in a group of dead trees, but this experiment is on the verge of ending as the trees lose branches. There is another small rookery at Churchill Forest Preserve, and a final one strung out along the Des Plaines River in and adjacent to southeast DuPage County.

 

Remembering the Indiana rookery, I was curious about what species of trees were supporting the Danada colony. On a recent frigid weekend morning I went there to find out. It had to be done in mid-winter, both to avoid disturbing the birds (which could begin to return by the end of February), and to take advantage of frozen ground and water for easy travel.

 

danada-gbh-rookery-3b

 

I found the colony to be situated in swampy woodland surrounding a large pond. Most of the 15-20 nest trees were living cottonwoods, and 90% of the nests were in these.

 

danada-gbh-rookery-2b2

 

Two of the nest trees were dead, and three were willows. One cottonwood had 16 nests, a couple had 13, and one had 11.

 

danada-gbh-rookery-1b

 

I counted a total of 142 nests. There may have been more; we have had some strong wind storms since the nesting season which could have dismantled some nests. Like sycamores, cottonwoods have open canopies and thick branches capable of supporting the relatively large stick nests herons construct. Most of the trees in the colony woods were cottonwoods, so a statistical examination limited to that bit of woodland would not reveal much about heron preferences. It appeared likely that the other trees there simply lacked the necessary support structure. A few willows were used, but each had the capacity for fewer nests. The better question is how the birds choose the rookery site in the first place. Trying to answer that would require a longer-term examination of many colonies.

%d bloggers like this: