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.

Advertisements

Literature Review: Winter Campfire

by Carl Strang

The Winter Campfire was my first winter series in this blog. In it I reviewed ideas pertaining to science and spirituality. Today’s post looks at relevant scientific papers from the past year. Sadly, none address the main question I was left with in the end: does time, as an independent entity, exist apart from our subjective experience of it? If not (or if so, given general relativity), how do we accommodate this in our understanding of reality?

OLYMPUS DIGITAL CAMERA

Morag I. Scrimgeour, et al. The WiggleZ Dark Energy Survey: the transition to large-scale cosmic homogeneity. Monthly Notices of the Royal Astronomical Society, 2012; 425 (1): 116 DOI: 10.1111/j.1365-2966.2012.21402.x

From a ScienceDaily article describing a mapping study. At the largest scale, matter in the universe is uniformly distributed, which supports the standard model of cosmology based on Einstein’s equations.

Robert Nemiroff, Ryan Connolly, Justin Holmes, Alexander Kostinski. Bounds on Spectral Dispersion from Fermi-Detected Gamma Ray Bursts. Physical Review Letters, 2012; 108 (23) DOI: 10.1103/PhysRevLett.108.231103

From ScienceDaily. The near-simultaneous arrival of 3 gamma ray photons at a space telescope, photons which had traveled 7 billion light years without distortion, supports a smooth space-time structure rather than one composed of tiny, Planck-length units which would have interfered with the rays’ similarly tiny wavelengths. (Loop quantum gravity, the leading contender to string theory or M-theory, thus suffers a blow with this result).

J-D. Bancal, S. Pironio, A. Acín, Y-C. Liang, V. Scarani, N. Gisin. Quantum non-locality based on finite-speed causal influences leads to superluminal signalling. Nature Physics, 2012; DOI: 10.1038/NPHYS2460

From ScienceDaily. They are proposing a test, involving 4 entangled particles, which may be feasible in the future and which may determine whether entanglement (described by Einstein as “spooky action at a distance”) happens through faster-than-light connection or communication among the particles (which would violate general relativity, and thus seems less likely, but might open the door to faster-than-light applications) or whether it happens by connections outside normal spacetime (which would imply a hidden connectedness of everything in the universe). The other possibility, that entanglement is the result of connections established beforehand, has been ruled out by other experiments.

Van J. Wedeen, Douglas L. Rosene, Ruopeng Wang, Guangping Dai, Farzad Mortazavi, Patric Hagmann, Jon H. Kaas, and Wen-Yih I. Tseng. The Geometric Structure of the Brain Fiber Pathways. Science, 30 March 2012: 1628-1634 DOI: 10.1126/science.1215280

They used a new technique to map the spatial relationships of nerve fibers in the brain, and found a basic pattern of fibers crossing at right angles in 3 dimensions, the whole curved topologically as the brain curves. They did similar analyses of 4 nonhuman primate brains and found considerable homology among the 5 species. This basic framework provides understanding of how embryological development coupled with evolution has been able to produce increasingly complex brains with relatively simple adjustments.

University of Chicago Medical Center (2012, October 1). Homolog of mammalian neocortex found in bird brain. ScienceDaily. Retrieved October 1, 2012, from http://www.sciencedaily.com­ /releases/2012/10/121001151953.htm

They describe a study published in the National Academy of Sciences that shows how the avian analog to the mammalian neocortex is clustered nuclei within a structure called the dorsal ventricular ridge. The same cells that layer to form the neocortex develop into these nuclei in birds. The neural pathways from the two different anatomical structures previously were known to be similar. The different arrangement makes possible an anatomical division of labor or specialization for different higher brain functions in birds.

Carissa L. Philippi, Justin S. Feinstein, Sahib S. Khalsa, Antonio Damasio, Daniel Tranel, Gregory Landini, Kenneth Williford, David Rudrauf. Preserved Self-Awareness following Extensive Bilateral Brain Damage to the Insula, Anterior Cingulate, and Medial Prefrontal Cortices. PLoS ONE, 2012; 7 (8): e38413 DOI: 10.1371/journal.pone.0038413

As described in a ScienceDaily article. A patient with damage to these brain areas, thought from past research to be the seat of self-awareness, passes every test for that capacity, seeming normal except for a loss of some memory formation ability. This demonstrates that self-awareness is more diffuse, involving a much larger part of the brain.

E.G. Milán, O. Iborra, M. Hochel, M.A. Rodríguez Artacho, L.C. Delgado-Pastor, E. Salazar, A. González-Hernández. Auras in mysticism and synaesthesia: A comparison. Consciousness and Cognition, 2012; 21 (1): 258 DOI: 10.1016/j.concog.2011.11.010

They found at least one instance of a person who could “see auras” in other people, who also has synesthesia in which his brain has associations between areas that normally are separate, particularly the face-recognition and color processing areas, as well as touch-mirror synesthesia, in which a person experiences the touch or pain sensations of another person the synesthete is observing.

William R. Rice, Urban Friberg, and Sergey Gavrilets. Homosexuality as a Consequence of Epigenetically Canalized Sexual Development. The Quarterly Review of Biology, 2012; 87 (4)

As described in ScienceDaily. Though there have been indications that homosexuality has a heritability component and thus is gene-caused or at least gene-influenced, efforts to find specific genes have failed. This modeling study describes the likely cause as an epigenetic fault. There are controls on gene expression which provide protections from the effects of opposite-sex hormones during development. These epigenetic controls normally are not passed on, but when they accidentally are passed on, from fathers to daughters or mothers to sons, they can produce effects including same-sex orientation. Note: sexual orientation was not addressed in the Winter Campfire series, but I decided to include this study here in part because this study is important and deserves wider attention, and in part because sexuality is a part of our experience as human beings, an important aspect of our nature, and so it is at least obliquely connected to The Wave Dreaming.

Lessons from Travels: Great Basin Ecology

by Carl Strang

A November conference in 2003 gave me the opportunity to take some extra time off, rent a car, and tour central Nevada. Previous Lessons from Travels posts have highlighted the Lehman Cave and Extraterrestrial Aliens aspects of that trip. Today’s focus is on the ecology of the Great Basin. This is an area where the crust of the Earth stretched thin, as though pulled from its eastern and western edges. It occupies much of Nevada, and extends south. The stretching produced a series of north-south cracks, or faults. Alternate wide blocks dropped down to produce low basins, and the areas between them thrust upward to produce narrow mountain ranges. The spacing of these ranges and basins is rhythmic and regular.

The low areas are flat and dominated by sagebrush, but there are plenty of other plants and animals to lend diversity to this desert.

The low areas are flat and dominated by sagebrush, but there are plenty of other plants and animals to lend diversity to this desert.

Higher mountains bounding the west edge of the Great Basin draw most of the moisture from the prevailing westerlies. The little remaining rain falls mostly on the ranges and evaporates, or soaks into the ground long before it can flow to the centers of the desert plains.

Here is a typical view of one of the many ranges that divide the basins. The dominant trees are singleleaf pinyon pines and Utah junipers.

Here is a typical view of one of the many ranges that divide the basins. The dominant trees are singleleaf pinyon pines and Utah junipers.

This landscape is not monotonous. There are abundant unique features sprinkling it. Sand Mountain is one example.

This enormous isolated dune is composed of sand blown up from a source 40 miles away. It stopped traveling when it hit a bight in one of the ranges.

This enormous isolated dune is composed of sand blown up from a source 40 miles away. It stopped traveling when it hit a bight in one of the ranges.

The thinning of the crust produced volcanic activity in places.

Core of an ancient volcano, dark with basalt.

Core of an ancient volcano, dark with basalt.

There are occasional badlands areas as well, where weakly cemented stone has eroded into beautiful shapes.

Cathedral Gorge badlands

Cathedral Gorge badlands

People have lived in this region for thousands of years, and left their mark in many areas.

Grimes Point petroglyphs

Grimes Point petroglyphs

Wildlife is diverse, as well, in the region.

Mule deer in the mountains

Mule deer in the mountains

I took a hike on the Pole Creek Trail, in Big Basin National Park.

The scene from my turn-around point

The scene from my turn-around point

On the way back down I found where a bobcat had stepped in my tracks.

The feline had passed within the hour.

The feline had passed within the hour.

The mountain chickadee is one of the delightful upland birds.

The mountain chickadee is one of the delightful upland birds.

The basins have their own array of wildlife.

Pronghorns occur in scattered small groups.

Pronghorns occur in scattered small groups.

It was still warm enough for a snake and other reptiles to be active in southern Nevada.

Striped whipsnake at Kershaw State Park

Striped whipsnake at Kershaw State Park

From its geology to its distinctive ecology, the Great Basin provides no end of contrasts that, upon reflection, help to define our own home region.

P.S. This is the 1000th post of this blog.

Blazing Stars in Winter

by Carl Strang

The blazing stars are among our showiest native wildflowers.

Prairie blazing star, Liatris pycnostachya, in bloom

Prairie blazing star, Liatris pycnostachya, in bloom

In winter the seeds drift away, leaving the 2-4-foot stalk.

Tip of a prairie blazing star in February

Tip of a prairie blazing star in February

This individual still retained most of the flower head bracts.

The tips of the bracts are acuminate, or drawn out into slender points, in this species. The points bend down, making them difficult to see in this photo.

The tips of the bracts are acuminate, or drawn out into slender points, in this species. The points bend down, making them difficult to see in this photo.

The stems also retain much of their fuzziness. Many of the stem leaves remain attached.

Part of the lower stem of a prairie blazing star.

Part of the lower stem of a prairie blazing star.

At Mayslake Forest Preserve I have a second species to compare, the marsh blazing star (L. spicata).

This marsh blazing star shed nearly all of its bracts. The few that remain have blunt tips.

This marsh blazing star shed nearly all of its bracts. The few that remain have blunt tips.

Marsh blazing star stems have small white dots, but are smooth rather than fuzzy.

Part of the lower stem of a marsh blazing star.

Part of the lower stem of a marsh blazing star.

Distinguishing these species requires a magnifying glass, but the blazing stars as a group are easy enough to recognize in winter.

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).

Literature Review: Invertebrate Biology

by Carl Strang

This week’s literature focus is on insects.

Dragonflies today are tiny compared to the giants of the Paleozoic. The following study looked at why they were so big then.

Dragonflies today are tiny compared to the giants of the Paleozoic. The following study looked at why they were so big then.

Matthew E. Clapham and Jered A. Karr. Environmental and biotic controls on the evolutionary history of insect body size. Proceedings of the National Academy of Sciences, June 4, 2012 DOI: 10.1073/pnas.1204026109

They reviewed maximal insect fossil wing lengths with respect to atmospheric oxygen, and found a positive correlation until the early Jurassic, when birds or flying dinosaurs and perhaps pterosaurs may have forced the increased maneuverability allowed by smaller body size. This came out of the observation that the enormous dragonflies and other invertebrates of the Paleozoic Era existed at a time when atmospheric oxygen was much higher than it is now. They were testing this hypothesis by correlating insect size with atmospheric oxygen. This study points out that freedom from aerial predators was another factor.

Blue-fronted dancer, brown female. In many damselflies, some females are colored differently from males, like this one, while other individuals have male-like colors. The following study looked at why.

Blue-fronted dancer, brown female. In many damselflies, some females are colored differently from males, like this one, while other individuals have male-like colors. The following study looked at why.

Iserbyt A, Van Gossum H, Stoks R (2012) Biogeographical Survey Identifies Consistent Alternative Physiological Optima and a Minor Role for Environmental Drivers in Maintaining a Polymorphism. PLoS ONE 7(2): e32648. doi:10.1371/journal.pone.0032648

They studied female color polymorphs in Canadian sedge sprites (in northeast Illinois found mainly in McHenry County). Their background review indicates that there has been considerable interest in damselfly female color variants. There is evidence in various studies for influences of environmental conditions such as temperature, but also avoidance of male harassment (accomplished by mimicking male coloration). Their results point to a tradeoff between investment in flight muscles vs. immune system, and suggest that both variants deal with male harassment in different ways. Those with an immune system emphasis are more male-like in coloration (presumably they have less problem with diseases and parasites, but then need to minimize male harassment by looking more “butch”), while those with flight muscle emphasis have colors more distinct from male colors (stronger fliers are better able to escape persistent males).

Lang, Michael, et al. 2012. Mutations in the neverland gene turned Drosophila pachea into an obligate specialist species. Science 337:1658-1661.

They found a few base pair substitutions that distinguished this fruit fly species from its near relatives. These changes render the flies unable to take cholesterol and transform it into essential hormones, but they can get replacement building blocks from their cactus host plant. This is an example of one way in which an insect species can become a specialist dependent upon its host.

Lessons from Travels: Upland vs. Lowland Tundra

by Carl Strang

Kokechik Bay, at the tip of the Yukon-Kuskokwim Delta in Alaska, provided a good opportunity to compare upland and lowland tundra communities.

Here is an aerial view of classical upland tundra interspersed with lakes.

Here is an aerial view of classical upland tundra interspersed with lakes.

In western Alaska, the distinction is clear. The more elevated areas, relatively dry and seldom if ever inundated by tides or floods, develop an upland tundra vegetation mix.

Mosses, lichens, dwarf shrubs and a few characteristic herbaceous plants dominate the upland flora.

Mosses, lichens, dwarf shrubs and a few characteristic herbaceous plants dominate the upland flora.

Here is a mix of lichens, mosses, and cloudberry, a member of the cosmopolitan genus Rubus.

Here is a mix of lichens, mosses, and cloudberry, a member of the cosmopolitan genus Rubus.

Some animals are connected with the upland tundra.

Black-bellied plovers nested in the uplands.

Black-bellied plovers nested in the uplands.

The eggs of the black-bellied plover blend perfectly with the lichens.

The eggs of the black-bellied plover blend perfectly with the lichens.

Willow ptarmigans associated more with the upland tundra, but made use of both habitats.

Willow ptarmigans associated more with the upland tundra, but made use of both habitats.

Lowland tundra was where we spent most of our time, in waterfowl related studies.

Grasses and sedges dominate the lowlands.

Grasses and sedges dominate the lowlands.

In coastal western Alaska, the lowlands are subject to at least occasional storm tide flooding. Many more species of birds nest in the lowlands.

Sandhill cranes are one of the more conspicuous lowland tundra birds.

Sandhill cranes are one of the more conspicuous lowland tundra birds.

The emperor goose is one of the iconic birds of this region and habitat.

The emperor goose is one of the iconic birds of this region and habitat.

As the continental glacier advanced and retreated across northeastern Illinois, the vegetation close to it no doubt had some tundra character. Little evidence remains, however, to give us a clear picture of this. Pollen records are more informative about the vegetation communities that followed as the climate warmed.

Two Winter Joe-Pyes

by Carl Strang

Two of our reasonably common plants in genus Eupatorium are called Joe-Pye weeds. There’s the purple Joe-Pye with its spotted stems, and the spotted Joe-Pye with its purple stems. Make sense of that. Anyway, today we’ll see what they look like in winter. The spotted Joe-Pye weed, Eupatorium maculatum, grows in open places, usually in or beside wetlands. The leaves are whorled, and this can be seen in the winter form.

Two whorls are visible in this photo.

Two whorls are visible in this photo.

At this point in winter the seeds are gone, but the framework of the fruiting structure remains. The inflorescence is described as flat-topped.

Though not obviously flat-topped now, the structure is large and spreading, and at least some of the lower stalks are relatively long to provide some sense of what might have been a somewhat flat-topped flower array.

Though not obviously flat-topped now, the structure is large and spreading, and at least some of the lower stalks are relatively long to provide some sense of what might have been a somewhat flat-topped flower array.

Here it is in bloom.

Here it is in bloom.

The rough-surfaced pedicels are attractive, I think, in winter.

Spotted Joe-Pye close look

Spotted Joe-Pye close look

Now we move to the nearby savanna and find some purple Joe-Pye weeds. They, like our first species, are very tall.

Purple Joe-Pye weeds also have whorled leaves.

Purple Joe-Pye weeds also have whorled leaves.

At Mayslake Forest Preserve, at least, the fruiting heads are smaller than those of spotted Joe-Pye weeds, and have a more compact, oval form in winter.

Again I find these structures delightful in their shape and texture.

Again I find these structures delightful in their shape and texture.

Habitat alone tells much of the tale in distinguishing these two plants, but taking a little time to compare them was an enjoyable winter project.

Mourning Dove Species Dossier

by Carl Strang

This week’s species dossier features a bird that is familiar and common. Over the course of my developing this dossier (established in the mid-1980’s) there seems to have been a change, with mourning doves wintering this far north with increasing frequency.

Dove, Mourning

Mourning dove

Mourning dove

Mourning doves usually live in open areas with some trees. In winter, they sometimes roost in thick evergreen plantations. They feed on the ground, picking up seeds. Nesting begins early in spring (March), with adults’ walking around, picking up sticks the first sign. Usually the first nest is in the branches of a conifer; subsequent nests may be in deciduous trees. The nest is a flimsy, loose platform of sticks. Two eggs almost always complete the clutch. Both adults incubate; early morning is a common switching time. The call is a mournful “cooweeoo, coo, coo-coo” (“bachelor song,” after literature). They produce a loud whistling of wings in flight. Generally they are not seen in northeast Illinois in winter, though occasional adults stick it out around feeders in Culver, Indiana. (Some were present all winter of 1998-9 at Willowbrook). There is a distinctive pumping of the head while walking. Mourning doves were very common in Texas, in brushlands, mountains and desert.

Mourning dove fledglings. This species lays 2 eggs per clutch.

Mourning dove fledglings. This species lays 2 eggs per clutch.

Late MY90, Hartz Lake. A mourning dove singing his bachelor song low in a tree flew off in a startle as a female sharp-shin landed in the same tree. The dove stayed within tree canopies as it flew.

27JA97. Morning. Snow fairly deep. A red-tailed hawk flew over the College of DuPage parking lot with something in its talons, pursued by half a dozen crows. The hawk perched on a flat-topped, wooden light pole and began plucking prey while crows sporadically left nearby perches and swooped at it. After 10-15 minutes it flew away, and I checked the feathers, which were scattered in singles and small clumps over a 20×30 foot area: mourning dove. Crow calls resembled owl mobbing, but smaller number of birds and less sustained.

MODO DE 3b

11MR99. First “bachelor calls” of the season at Willowbrook.

31OC01. At least 20 mourning doves, more than I have seen together in months in northeast Illinois, at a savanna area in the Nelson Lake property, Kane Co.

MODO DE 1b

18FE05. First bachelor calls of the season, Winfield Mounds.

Mourning dove incubating its nest

Mourning dove incubating its nest

30MR09. Mayslake. A pair of mourning doves has a nest in a spruce in front of the mansion. (This nest later was abandoned, possibly because of the heavy human traffic that was passing close by).

Literature Review: Wolves and Coyotes

by Carl Strang

New information about coyotes and wolves always seems to have a little extra zest.

Coyote

Coyote

Hennessy, Cecilia A., Jean Dubach, and Stanley D. Gehrt. 2012. Long-term pair bonding and genetic evidence for monogamy among urban coyotes (Canis latrans). J. Mammal. 93:732-742.

This study was yet another contribution from the group led by Stan Gehrt of Ohio State. Chicago region coyotes are monogamous (litters show common parentage), and pair bonds are long-lasting. (Note how many person-weeks of intensive study can produce a primary result that can be stated in a single sentence.)

Wheeldon, Tyler, and Brent Patterson. 2012. Coyotes in wolves’ clothing. Am. Midl. Nat. 167:416-420.

They examined 3 pups from the northern Lower Peninsula of Michigan which were wolf-like. These proved to be “coyotes but revealed evidence of maternal introgression from a Great Lakes wolf in their pedigree. These findings suggest that Great Lakes wolves are capable of interbreeding with coyotes when conspecifics are rare.” Tracks and trail camera images from the area had shown what appeared to be a wolf, but these results point to an unusually large coyote or a hybrid. They think the most likely scenario is that a wolf immigrated from the Upper Peninsula population and mated with a coyote. This study caught my eye because of my experience of hearing a possible wolf-plus-coyote chorus at Chain O’Lakes State Park last summer.

Wolf at Wolf Park in Indiana

Wolf at Wolf Park in Indiana

William J. Ripple, Robert L. Beschta. Large predators limit herbivore densities in northern forest ecosystems. European Journal of Wildlife Research, 2012; DOI: 10.1007/s10344-012-0623-5

(As described in ScienceDaily article). In a review of data from all around the Northern Hemisphere, they found that the removal of large predators, especially wolves, has had a profound negative effect on forest ecosystems. In their absence, deer and other large herbivores achieve population densities 6 times larger; their overconsumption of plants interferes with tree reproduction, and has a cascading impact on biodiversity generally. Erosion increases, stream and forest quality decreases, and carbon sequestration is greatly reduced. Effects are multiplied by other large and medium-sized predators which are supported in some seasons by scavenging from wolf kills. Because of this, the year-round behavioral response of the herbivores to the wolves, and the more limited removal of the herbivores, human hunting is not a completely equivalent substitute (as Aldo Leopold learned to his chagrin from the Kaibab Plateau fiasco).

« Older entries

%d bloggers like this: