September 2015 Inventory

Checkered-Skipper (Pyrgus sp.), Boca Raton, FL, September 11, 2015.
Here's a somewhat complete list of the insects and spiders seen around the yard last month (those that I've noticed, those that I've taken pictures of, and those that I've been able to ID). Some of them are linked to ID pages on Others aren't. If it was a new species for the yard, I've indicated it as such, along with a link to the write-up on the blog. (Some of which I still haven't even caught up with yet...) Butterflies
  • Swallowtails (Papilionidae)
    • Giant Swallowtail (Papilio cresphontes)
      Giant Swallowtail (<em>Papiliio cresphontes</em>). Boca Raton, FL, September 2, 2015.

      Giant Swallowtail (Papiliio cresphontes). Boca Raton, FL, September 2, 2015.

    • Polydamas Swallowtail (Battus polydamas)
  • Whites and Yellows (Pierids)
  • Blues, Coppers, and Hairstreaks (Lycaenidae)
    • Cassius Blue (Leptotes cassius)
    • Martial's Scrub-Hairstreak (Strymon martialis)
      Martial Scrub-Hairstreak (Strymon martialis), head-deep in the weeds.

      Martial Scrub-Hairstreak (Strymon martialis), head-deep in the weeds.

    • Mallow Scrub-Hairstreak (Strymon istapa)
  • Brushfoots (Nymphalidae)
    • Queen (Danaus gillipus)
    • Monarch (Danaus plexippus)
    • Gulf Fritillary (Agraulis vanillae)
    • Zebra Heliconian (Heliconius charithonia)
  • Skippers (Hesperiidae)
    • Fiery Skipper (Hylephila philaeus)
    • Three-spotted Skipper (Cymaenes tripunctus) (New yard bug, no write-up yet)
      Three-spotted Skipper (<em>Cymaenes tripunctus</em>). Boca Raton, FL, September 23, 2015.

      Three-spotted Skipper (Cymaenes tripunctus). Boca Raton, FL, September 23, 2015.

    • White Checkered-Skipper (Pyrgus albescent) (New yard bug!):
      Checkered-Skipper (Pyrgus sp.), Boca Raton, FL, September 11, 2015.

      Checkered-Skipper (Pyrgus sp.), Boca Raton, FL, September 11, 2015.

    • Long-tailed Skipper (Urbanus proteus)
    • Monk Skipper (Asbolis capucinus); very high numbers this month (8–9 individuals at once)
    • Horace's Duskywing (Erynnis horatius)
Moths Odonates
  • Damselflies (Zygoptera)
    • Citrine Forktail (Ischnura hastata)
    • Rambur's Forktail (Ischnura ramburii)
    • Everglades Sprite (Nehalennia integricollis)
  • Dragonflies (Anisoptera)
    • Band-winged Dragonlet (Erythrodiplax umbrata)
    • Blue Dasher (Erythrodiplax longipennis)
      Blue Dasher (<em>Pachydiplax longipennis</em>). Boca Raton, FL, October 10, 2015.

      Blue Dasher (Pachydiplax longipennis). Boca Raton, FL, October 10, 2015. (Yes, October, but I saw them in September, too.)

  • Honeybee (Apis mellifera)
  • Leafcutter bee (Megachile petulans)
  • Leafcutter bee (Megachile albitarsis) (new to the yard!)
    White-footed Leaf-cutter Bee (Megachile albitarsis). Boca Raton, FL, September 3, 2015.

    White-footed Leaf-cutter Bee (Megachile albitarsis). Boca Raton, FL, September 3, 2015.

  • Sweat Bee (Agapostemon splendens)
  • Sweat Bee (Halictus poeyi)
  • Sweat Bee (Lasioglossum lepidii)
  • Chalcid wasp, Conura sp.
  • Chalcid wasp, Eurytoma sp. ("new" to the yard!)
    Tiny chalcid wasp, family Eurytomidae. Boca Raton, FL, September 13, 2015.

    Tiny chalcid wasp, family Eurytomidae. Boca Raton, FL, September 13, 2015.

  • Chalcid wasp, Brachymeria sp. ("new" to the yard!)
    Chalcid wasp, genus Brachymeria. Boca Raton, FL, September 16, 2015.

    Chalcid wasp, genus Brachymeria. Boca Raton, FL, September 16, 2015.

  • Myzinum wasp (Campsomeris dorsata)
  • Metallic Blue Ladybeetle (Curinus coeruleus)
  • Asian Multicolored Ladybeetle (Harmonia axyridis)
  • Click beetle, perhaps Diplostethus carolinensis
Bugs Flies
  • Condylostylus mundus
    Long-legged fly, probably <em>Condylostylus mundus</em>. Boca Raton, FL, September 30, 2015.

    Long-legged fly, probably Condylostylus mundus. Boca Raton, FL, September 30, 2015.

  • Palpada vinetorum
  • Plagioneurus univittatus
  • Toxomerus geminatus
  • Sarcophagidae sp.
  • Phytomizinae sp.
  • Hentzia palmarum
  • Gasteracantha cancriformis
  • Menemerus bivittatus
  • Argiope trifasciata
  • Leucauge venusta

Depth of field, part two

In my post last week I talked about how depth of field is critical to macro photography. I found a couple of photos of that Citrine Forktail where it's even more apparent, although it's a bit difficult to tease out what's a result of the angle at which the photo was taken (was the camera perpendicular to the long axis of the insect or not?) and what is due entirely to depth of field. I suspect that I might have inadvertently rotated the camera slightly. The first photo was taken at f/11, which is the "standard" aperture for macro photography out of doors. The region of best focus is centered on the damselfly's eye and the body is rather blurry:

Ischnura hastata. f/11, 1/400. Eye in perfect focus, most of body blurry.

The second image is taken at an even smaller aperture, f/14, with a correspondingly greater depth of field. And while the eye isn't in as good a focus, the entire body is crisp and clear:

Ischnura hastata. f/14, 1/250 exposure. Eye slightly blurry, body entirely in focus.

To get a better idea of what I mean when I say that the eye is in perfect focus in the top image and in not such perfect focus in the second image, here are cropped views of the two images:
The eye, legs, and thorax are in excellent focus.

The eye, legs, and thorax are in excellent focus.

Here is a cropped view of the eye in the second image. Notice how much less impact this crop has than the first one; it turns out that the eyes are critical to good insect photography. (If you don't agree that the first crop is better than the second one, click on the image to get the full size version; it should be much easier to see.)
The eye is not in perfect focus, but the thorax and the rest of the body are crisp and clear.

The eye is not in perfect focus, but the thorax and the rest of the body are crisp and clear.

The question is, how much of the difference is due to the slight difference in depth of field, and how much is due to any inadvertent camera rotation (or movement of the subject itself)? The only way to answer that is to have a guaranteed stationary camera (use a tripod) and a guaranteed stationary subject (difficult for wildlife photography). The trouble with tripods, of course, is that they're difficult to set up and to move in areas that are dense with vegetation, which just happens to be the type of area damselflies frequent. If by chance the insect alights in a cleared-off area, chances are that maneuvering a tripod into the area will be enough to scare it off. I'm tempted to try a monopod for two reasons: first, it will help steady the camera, even if it won't guard completely against rotation issues; second, it can serve as a walking stick and, in a pinch, to beat back brush, clear aggressive spiderwebs, etc.

Shooting through glass doors

When you have the opportunity for a photo of a bird in a nice setting, you run for your camera. This Northern Cardinal was singing in the starburst and bougainvillea on our neighbor's property, in perfect view of our glass doors in back. So I went and grabbed my camera and fired off a few shots through the dirty glass before attempting to head outside and get a clear shot.
Northern Cardinal (Cardinalis cardinalis). Boca Raton, FL, March 1, 2013.

Northern Cardinal (Cardinalis cardinalis). Boca Raton, FL, March 1, 2013.

Unfortunately, I had neglected to factor the toddler into the equation. Seeing the open door, he rushed to close it, not realizing (or not caring) that his beloved daddy was trying to squeeze off a few shots using the doorframe to steady the camera. The last thing I saw before my eye exploded in blinding pain was this:
The fast approaching door.

The fast approaching door.

A good photographer must always be aware of the dangers around him.

Spread your wings at Pondhawk

The Monday after Thanksgiving is a great time to get out to a nearby natural area. While most folks are back at work after a four-day weekend, those of us who have the foresight to request this day off get to experience something fairly rare around this time of year: solitude! The prospect of some alone time, combined with the knowledge that two of Palm Beach County's best birders had reported a juvenile Red-headed Woodpecker at a location near me decided my destination on this fifth day of a four-day weekend: Pondhawk Natural Area, which, as loyal readers of this blog know, was formally opened just a couple of months ago. And on this day, as expected, I had the place all to myself! I started out on the concrete walking trail, chasing warblers and other birds as the fancy struck me, and I wound up assembling a fairly respectable list without even trying very hard—28 species, including House Wren, American Kestrel, Osprey, Red-shouldered Hawk, and the target bird: Red-headed Woodpecker. But that wasn't the only, or even the primary, goal of the excursion. I just needed to get back out into one of the prettiest natural areas in Boca Raton. It's a very pretty park, with 5 different ecological communities (you can't really call these tiny snippets of area "ecosystems")—scrub, scrubby flatwoods, mesic flatwoods, hydric hammock, and sawgrass slough. I spent most of my time on that concrete trail, which winds through the mesic and scubby flatwoods (yellow and green areas in the map below) that surround the pond (the orange hydric hammock in the map), but I also took an excursion onto the sandy trail that leads through the southwestern portion of the site (also mesic and scrubby flatwoods). I never did get onto the trail through the scrub proper. Both scrubby flatwoods and "true" scrub are dominated by shrubby, scrubby plants that don't need a whole lot of water: sand live oak, saw palmetto, prickly pear cactus, etc. Where there are "woods" around (hence scrubby flatwoods), they are usually sand pine or, in slightly wetter scrubs (mesic, halfway between dry [xeric] and wet [hydric] sites), slash pine. The flatwoods areas at Pondhawk have numerous snags (dead trees left standing in the wake of a wildfire on this part of the site back in 2010) and living slash pine trees, providing excellent foraging and even nesting habitat for woodpeckers like the red-bellied (common in Palm Beach County) and red-headed (much rarer in Palm Beach County): Another characteristic plant of scrub or scrubby flatwoods is Feay's Palafox, with its interesting tubular flowers arranged into a very pretty cluster (called an inflorescence): You should always look closely at flowers; then, when you think you've seen everything, take a picture. I knew there was an ant hitchhiker on this flower, but I didn't notice the pale creature on the second "tube" from right until I got the image onto the computer. I have no idea what the pale creature is; I was assuming jumping spider at first, but it's not in focus and no matter how hard I squint, I can only make out 4 or 5, not 8, legs. And the body is rather elongate for a spider, although some of those tiny jumping spiders can be fairly "tubular." Heck, it might not even be an animal! When I arrived at Pondhawk, I was just hoping to see some pretty scenery like that flower; I had little to no expectation of actually encountering the "object" of my visit (the aforementioned Red-headed Woodpecker). I don't chase birds, and I don't really even go out of my way for them; I just like to get out into nature and, while I'm there, they're one of the more interesting things to look at—when I can tear myself away from the plants and the insects, that is. And when I do set out with a specific bird in mind, more often than not I miss it, anyway, so perhaps I'm only making a virtue out of necessity by deciding to focus on the whole experience, rather than the "goal." This time, though, I got a bit lucky: I actually did "get" the bird. I can't say, though, that I got a satisfying picture of it; it was always just too far away, or just on the wrong side of the sun, or the sun was behind a cloud, or it flew right over my head and I couldn't focus fast enough. Still, I managed to document the bird, which was nice: Everyone's still a bit confused about what this bird is doing here, so far south of its known nesting sites in the county. Red-headeds are slightly migratory, in that they move locally in winter to exploit better resources than they can find near their nesting sites, but only if their nesting sites are deficient in some food resource. Up north, a poor mast crop (acorns) is what triggers this migratory response; down here, with seemingly abundant year-round resources, it's a bit of a mystery why this juvenile bird would wander like this. Eventually the woodpecker got tired of me chasing it from snag to snag, and decided to fly right over my head (too quickly for me to get a picture, drat it) and back up to a site far enough away that it wasn't worth hiking over to, so I continued on my way and left him (or her) in peace. On the way out I got a couple of other decent shots, like this Red-shouldered Hawk perched on a tree overlooking the pond, thus doing its best to look like the avian version of the "pondhawk" for which the site is named: What really got me excited, though, was my first-ever sighting (well, documented with a photo anyway) of one of the spreadwing damselflies, Carolina Spreadwing (Lestes vidua): Carolina Spreadwing is the only spreadwing we're likely to see this far south in Florida; the only other species that occur in our area are either blue or green, not mostly brown. Very little appears to be written about this species, so I can't tell you much about it. The generic name, Lestes, means robber (some say predator) in Greek; vidua means widow in Latin. The official etymologists of North American odonates, Paulson and Dunkle, list this specific name as "widow; allusion unknown." And that's all I can tell you about it as well! This very young female (based on coloration) did her best to elude me, and she even exhibited some behavior that our great Florida odonatologist, Sid Dunkle, describes as follows:
Interestingly, they close their wings over their backs, and drop their bodies to parallel their perch, when a dragonfly flies near. Pairs in tandem do this also, but the approach of a human does not elicit this behavior.
Now, there were plenty of dragonflies flitting about, so I can't exclude the possibility of this damselfly doing this in response to them rather than to me, but on both perches that I chased this little lady to, she closed her wings over her back in what I thought was a response to my approach: This behavior confused me so much that I couldn't be positive this wasn't a "normal" damselfly that was exhibiting spread-wing behavior, rather than a spreadwing exhibiting "normal" behavior. When I got home and read Dunkle's description, I felt a little better about my ID on the bug. It still hasn't been confirmed by either bugguide or Odonata Central, but I'm fairly confident she is who I say she is. Hope to see you out and about next time!

October 2012 full moon

October 28. 2012 Full moon
The Hunter's moon rises nearly or completely full over three successive nights at nearly the same time each night. On Eastern Daylight Time this year, the nights of the 27th, 28th, and 29th, at 5:21, 5:57, and 6:35, respectively. Full moon is today at 3:50 p.m. EDT, but this shot was taken last night right around 10 p.m. It was relatively far away (402 000 km), and the libration was a little over 4 degrees both east (eastern limb tilted toward Earth) and south (southern limb tilted toward Earth). With the eastern tilt, you can just barely make out the margin of Mare Marginis and Mare Smythii on the right edge (Smythii on the equator, Marginis just north of that), and with the southern tilt, if you follow the "7:30" rays from the bright rayed crater Tycho in the southern hemisphere, you should be able to see—if I've worked out the confusing selenography correctly—the dark floors of the large craters Schickard and Schiller. Clavius looks as large as a lunar sea, with the prominent crater Porter in its northern rim:

Southern lunar highlands with prominent features labeled. The only one I'm sure of is Tycho.

I'm having a bit of a problem with the labeling, though. Tycho is obvious. I'm fairly sure I've labeled Schickard and Schiller correctly. But if Clavius is that giant area near the south pole that looks almost as big as a lunar sea, something's wrong. With the southern limb tilted four degrees toward us, I'm surprised to see Clavius looking like it's on the southern limb. (Then again, four degrees isn't a huge tilt; when I simulate the view by looking at my awesome new moon globe, it's hard to make out Clavius way down there on the bottom.) I'll have to try again tonight, perhaps with higher magnification. Here's the full moon gallery to date; I've only missed a couple since December 2009!

Millipede season

It's millipede season again here in Boca, although down in the Keys, it started back in August. Don't worry, though; they're no threat to your health or safety. From the UF/IFAS factsheet ENY-221/IG093 (available on their website):
Centipedes and millipedes are commonly seen in yards and occasionally enter homes. Neither centipedes nor millipedes damage furnishings, homes, or food. Their only importance is that of annoying or frightening individuals.
That may be true, but they are certainly good at annoying me this time of year. And this year in particular we seem to be experiencing a bumper crop of them. Here's a closeup of a particularly striking one that Eric pointed out to me the other day: Whenever the kids see one, the reaction is pretty intense: First, some taxonomy: centipedes and millipedes are not insects. Both belong to taxonomic groups named after their most prominent features: their many, many legs. Centipedes have one pair of legs per body segment and belong to the class Chilopoda (from the Greek chilios, "thousand"); millipedes have two pairs of legs per body segment and belong to the class Diplopoda (from the Greek diplo, twofold). Both taxonomic classes are subsumed into the subphyllum Myriapoda. Thus, they can be called chilopods, diplopods, or myriapods with equal accuracy (but not equal specificity). However, if you clicked the "taxonomy" link above, you'd have discovered that nobody really knows what they're talking about, taxonomically, with regard to the millipede. Next, some anatomy. Millipedes (centipedes too) consist of two basic regions: a head and a trunk. The trunk is made up of a series of body segments bearing legs (remember, one pair of legs = centipede, two pairs = millipede) on all but the first four thoracic body segments. As a very convenient website puts it.
Most of the trunk segments carry two pairs of legs (hence the name 'diplo'- two 'poda' - feet). This is because the apparent trunk ringed segments are actually 'diplosegments' formed by the fusion of two trunk segments. The first ring after the head (collum) is legless and the following three rings carry one leg pair each.
This fusion of body segments in millipedes explains why their cousins the centipedes are much more flexible, capable of winding around and over objects and bending in more than one segment at a time, while millipedes proceed more, as Thomas Eisner writes, "bulldozer fashion." This is because the body segments of millipedes are actually fused together, rather than individual articulating segments. So while a millipede can curl up, it can't really bend in too many directions at once. If you'd like to read more about their fascinating method of locomotion, click on the image below (by Julia Molnar, PhD student at the Royal Veterinary College and paleoartist extraordinaire). Myriapods are detritivores, which means that they feed on decaying plant material and organic matter; they don't damage living plants. They also don't bite. They do emit chemical secretions that could, possibly, bother someone, but in quantities so small that it's rarely a problem unless a curious researcher (usually a child) gets too close to the wrong species. While there are many species native to Florida, there are also many introduced species. The two species most commonly seen at our house are the native Chicobolus spinigerus, the Florida Ivory Millipede, and (I'm fairly sure; millipede ID is not my specialty) the introduced Trigoniulus corallinus, Rusty Millipede. Here's one that Daniel and Eric enjoyed pointing out to me: I believe it to be the Rusty Millipede, but the only resource I know of that even lists all the Florida species (Shelley 2000) does not include photos. There are only 51 species according to this source, though, so it wouldn't be outrageously hard to try a Google image search for each one; it's just time-consuming.  There might be a native look-alike, for all I know. There's another introduced species, Rhinotus purpureus, that looks quite a bit like T. corallinus; far too similar for a nonspecialist like me to tell, at least without a key. Chemistry The chemical defenses of several Florida millipedes have been studied by the late Thomas Eisner, who used to visit the Florida scrub up at Archbold Biological Station on research summers when he wasn't teaching at Cornell. One species, Floridobolus penneri, the Florida Scrub Millipede (and endemic to that habitat), emits a mixture of benzoquinones that completely deters all insect predators, except for the larvae of one beetle, specially adapted to prey on these millipedes. These larvae have their own chemical offense (the gut fluid) that preempts the millipedes' defense by paralyzing the millipede completely, so that the defensive glands of the millipede never get a chance to come into play. You can read all about it here., although I read about it first in Eisner's book for the layperson, Secret Weapons. In fact, monkeys and grackles appear to use the secretion of one Caribbean species now found in Florida (the yellow-banded millipede, Anadenobolus monilicornis) for its insect-repellant qualities. At least, both primates and birds have been documented rubbing this "bug" on their bodies or under their wings. Here's one of the many that frequent our outside walls and, sadly, our inside ones as well (They dry up pretty quickly indoors, so it's best to just leave them alone and then sweep up the detritus): I've seen a similar millipede referred to on as "Eurhinocricus," so perhaps there are two species, or there is taxonomic confusion/"updation" at work. Etymology/Usage Note Many scientific articles "misspell" millipedes as millipeds. That's not a misspelling; that's just the way scientists like to refer to things. Presumably the practice arose from the much more common practice of "inventing" a quasivernacular name from the Latin name for an animal. For example, members of the gull family, Laridae, are often referred to as larids; the Bromeliacaea are often called bromeliads. Thus, I imagine, from "millipede" we get "milliped." For example, the most recent annotated checklist of Florida's millipedes (sans images, sadly), follows this practice:
The milliped fauna of Florida consists of 8 orders, 18 families, 34 genera, and 51 species and subspecies; it comprises six elements: widespread species occurring widely in Florida, northern species reaching their southern limits in north Florida, neotropical species occurring naturally in Florida or adventive there, oriental adventives, Florida endemics, and southeastern endemics.
As you can see, the analogy is imperfect: the quasivernacular name (if that's what it is) milliped is just a shortening of the already vernacular name, rather than the presumably unwieldy latinate name for millipede (which, you recall, is Diplopoda). If authors called them "diplopods," I'd understand. I'm still flummoxed by "milliped," but I've seen it often enough to know that it's not a "mistake." Another possibility is that milliped is just the adjectival form of the noun millipede. That is, when describing the attributes of millipedes, one simply drops the final e: milliped fauna. I'm not convinced. After all, the "aberrant" form milliped is used both as noun and adjective. When you run out of reasoned argument, try the dictionaries. First, the standard dictionary in American book publishing: Merriam-Webster's 1th Collegiate. MW11 lists the "normal" spelling, millipede, no variant spellings, a reasonable definition, and gives a date of 1601 for the first usage in its records. The next resource in my method is the American Heritage Dictionary, now in its 5th edition. It lists "millipede, also millepede," gives no date, and defines the animal more or less straightforwardly. Next, the entomologist's favorite dictionary, no longer in print but available online: the Century Dictionary, which is often very helpful in providing meanings for taxonomic names. That resource lists millipede as "same as milleped," and under that entry (milleped, milliped) defines the animal more or less straightforwardly. Not much help explaining the variations in spelling, unfortunately. Time to bring out the really big guns: the Oxford English Dictionary (OED) lists milliped as a variant of millepede. Under that main entry, the OED lists even more variants, some less and some more familiar: millipeed, millepide, milleped, and, last and apparently least, our version, millipede. So the "new" spelling is the one we Americans are used to: millipede. The OED, lovely resource, dates the 1601 spelling as "millipeed" (from a translation of Pliny), a 1706 millepeda, and gives two resources (1835 [Kirby] and 1877 [Huxley]) for the modern American spelling, millipede. Conclusion? Usage is mixed. Go with whatever your journal editor recommends, if you're publishing. Go with whatever pleases you, if you're blogging. References Eisner, T. 2005. Secret Weapons. Defenses of Insects, Spiders, Scorpions, and Other Many-Legged Creatures. Cambridge, MA: Belknap (Harvard UP). Shelley, R. M. 2000. Annotated checklist of the millipeds of Florida (Arthropoda: Diplopoda). Insecta Mundi.Paper 316.htp://

New backyard bird: Chimney Swift

A bird that's probably familiar to many of you is Chaetura pelagica (Linnaeus, 1758), more commonly known as Chimney Swift. It's been described by Alexander Sprunt (1954) as "resembl[ing] in appearance a cigar on wings" because of its tubular body and long, long wings. Most of the time you see it on the wing, flying overhead chasing down its insect prey, and twittering like mad. It always reminds me of the last line of one of the most famous of Keats's odes, "To Autumn":

Where are the songs of Spring? Ay, where are they? Think not of them, thou hast thy music too,— While barred clouds bloom the soft-dying day, And touch the stubble plains with rosy hue; Then in a wailful choir the small gnats mourn Among the river sallows, borne aloft Or sinking as the light wind lives or dies; And full-grown lambs loud bleat from hilly bourn; Hedge-crickets sing; and now with treble soft The red-breast whistles from a garden-croft; And gathering swallows twitter in the skies.

Keats's swallows are what we call here in the States "Barn Swallows," Hirundo rustica (Linnaeus, 1758). They are the most widespread species of swallow in the world, and they are what the poet saw at dusk on September 19, 1819, as he wrote what was to become the most anthologized poem in the English language. We have Barn Swallows here in Florida, with records in every season for Palm Beach County. We see them gathering in large flocks on our annual trips to the flooded fields of western Palm Beach County in August, and  they are even reported breeding in neighboring Hendry County.

But the bird that occurred today at my house, while it looks largely similar to the swallow through the process known as convergent evolution, is not even closely related to the swallow family. (The idea of convergent evolution is that animals that specialize in similar ecological niches, the way swallows and swifts specialize in catching insect prey on the wing, often evolve similar body shapes. In this case, long, pointed wings and a beak with a large gape. In a more general example, the wing itself evolved separately in the mammalian, insect, and avian groups.)

Chimney Swifts are actually more closely related to the hummingbirds than to the swallows they resemble. This fact has been known at least since Arthur Cleveland Bent's magisterial series on North American birdlife: Life Histories of.... Bent published the volume on Cuckoos, Goatsuckers, Hummingbirds and their Allies back in 1940 as United States Museum Bulletin 176, although most birders with extensive libraries have the Dover edition, which the publisher released in two slim volumes to increase their profit margins. (After starting this post, I found out that the text is available online as well, so you don't even have to go to the trouble of devoting 3 or 4 feet of bookshelf to the printed version.)

Bent writes of the migratory nature of this bird:

From its unknown winter quarters, somewhere in Central America or on the South American Continent, the chimney swift comes northward in spring and spreads out over a wide area, which includes a large part of the United States and southern Canada.

Individually, the swift is an obscure little bird, with a stumpy, dull-colored body, short bristly tail, and stiff, sharp wings, but it is such a common bird over the greater part of its breeding range and collects in such enormous flocks, notably when it gathers for its autumnal migration, that as a species it is widely known.

Does that last sentence remind anyone else of Keats's swallows? Hmmm? Well, never mind, then...

The write-up in Sprunt (1954) and Stevenson and Anderson (1994) updates Bent's "unknown winter quarters" to a locale in the upper Amazon Basin, determined by bird banders in the 1940s, who recovered a few birds banded in Tennessee. According to Sprunt,

The Chimney "Swallow" as it is often and erroneously called, is one of the most familiar birds of the country, as it appears in multitudes about human habitation.... Not the least interesting thing about this very interesting bird was, until recently, the mystery of its winter home. No one knew for certain where it was. Then, in May of 1944, word was received from the American embassy in Lima, Peru, that some bands had been turned in, "secured from some swallows killed by Indians" along the border of Peru and Colombia, some 6 months earlier. Most of the "swallows" were Chimney Swifts and had been banded in Tennessee (F. C. Lincoln, Auk, 61:604, 1944). Thus a mystery was solved and the supposition that some of the birds wintered in South America vindicated.

Bent describes the behavior of this bird in terms of its "curious" relationship to people:

Although the species spends the summer scattered over a large part of the North American Continent, it never, except by accident, sets foot upon one inch of this vast land. The birds build their "procreant cradle" in the chimneys of thousands of our homes and crisscross for weeks above our gardens and over the streets of our towns and cities, yet, wholly engrossed in their own activities far overhead, they do not appear to notice man at all. Indeed, it is easy to believe that the swift is no more aware of man during the summer, even when it is a denizen of our largest cities, than when in winter it is soaring over the impenetrable jungles of Central America.

How do we regard this bird that does not know we are on earth? We are glad to have swifts breed in our chimney; we like to see them shooting about over our heads, and we enjoy their bright voices; yet, do we feel such friendship for them as we feel for a chipping sparrow, for example, which builds sociably in the vines of our piazza? The little sparrow may be wary, and may fly away if we come too near, but at least it pays us the compliment of recognizing our existence. The swift, however, is not even a semitrustful neighbor; it is a guest that does not know we are its host. We may almost think of it as a machine for catching insects, a mechanical toy, clicking out its sharp notes. But let us note this fact. Every ten years or so the swifts do not appear about our house in the spring. Something has gone wrong on their journey northward. Our chimney will be empty this year; there will be no dark bows and arrows dashing back and forth above our roof, no quick pursuits and chattering in the evening. All summer something is lacking because there are no swifts to enliven the season. We realize, now that they are gone, how we should miss their active, cheerful presence, if they never came back again. But we may be sure they will come back--next year perhaps--to visit us again, this most welcome "guest of summer."
I always enjoy hearing them pass about overhead, when I'm gardening or swimming with the kids in the pool. Whenever I hear them twittering, I point it out to the boys. Eric is starting to get mildly interested in it, at least to the extent of agreeing that birds are "so pretty" and their songs are "so nice." Daniel, on the other hand, is absolutely ga-ga over birds, at least the prints of birds that we have hanging on our walls. Speaking of hanging on our walls, I haven't even gotten around to showing you the impetus for this post! For the past couple of days, I've noticed that there is a rather insistent quality to the chittering near our house, and yesterday I heard flapping in our chimney. Could it be? Could our chimney be blessed with a swift family building its nest? I still don't know the answer to that question, but a look up top shows that the possibility certainly exists:

Open chimneys invite Chimney Swifts to move in.

And since our fireplace doesn't have a flue (there's something in there that blocks the rain and catches the leaf litter that blows in, but there is evidently still a large passage through which animals can squeeze), this morning my office was paid a visit by one of the birds itself. Imagine my surprise on entering my little office to hear a flapping inside the room! I saw a little black bird up on top of my tall bookshelves and immediately closed the door to make sure the creature didn't fly into the rest of the house where it might get irretrievably lost or hurt. Then I opened the window, removed the screen, and began trying to herd it out through the opening. Easier said than done. After a few minutes of trying to get close enough to it with the screen in hand so that I could sort of shoo it out, I gave up on the hands-off approach and decided I'd better just let it settle down somewhere while I took a few pictures and thought things through. No sooner thought than done. After I stopped chasing it, it seemed to take some comfort, settling in to a cozy resting place on the top shelf, which, as it happened, is the home of my copies of Bent's fine Life Histories series: Here you can see it clinging to volumes two and three of Cardinals, Grosbeaks, Buntings, Towhees, Finches, Sparrows, and Allies. (Apparently it can't read, or doesn't know its place in the taxonomy of North American bird life!) Eventually I was able to get close enough to it to take a decent portrait: Then, perhaps proleptically encouraged by the words I was soon to read in Bent's write-up of the species ("banders who have handled the birds report that they show little or no fear (or consciousness) of man and appear tame to an extraordinary degree"), I was able to sneak up on it from below and wrap it up in a towel. I was concerned that it would be as nervous and fluttery as it was when I first walked into the room and surprised it, but it went completely still and allowed me to snap a few awkward shots with my left hand, while holding it in my right: Here you can see the bristly tail feathers Bent described, and you can also see how much longer the wings are than the tail. ("Primary projection," that is, the difference between the end of the longest of the innermost wing feathers (tertials) and the end of the longest of the flight feathers (primaries), is a different metric, and is of little use in identifying swifts or swallows because they're always flying so you never see it!) After a couple of clumsy left-handed shots, I took pity on the poor bird and set it on the windowsill and removed the towel, whereupon it instantly sprang into action, whirred once around the tiny courtyard, and hasn't been seen since. References Bent, A.C. (1940). United States National Museum Bulletin 176. Repr. 1964, New York: Dover. Available online as Life Histories of North American Birds. Sprunt, A. (1954). Florida Bird Life. New York: Coward-McCann, National Audubon Society, USFWS and Florida Game and Fresh Water Fish Commission. Stevenson, H.M., and B.H. Anderson. (1994). The Birdlife of Florida. Gainesville: University Press of Florida.  

New backyard bug: Ischnura posita

One thing that I'm really enjoying about the new place is that I've seen several species of damselfly in the backyard in the little more than a year that we've been here. The old place had lots of dragon- and butterflies but, perhaps because there was no backyard pool, there were no damselflies, at least that I recall. So far I've seen a couple of species of Forktail (Ischnura ramburii and I. hastata), a sprite or two (Nehalennia pallidula),  a bluet (Enallagma sp., probably doubledayi) and an unidentified spreadwing species ("documented" by perhaps the worst photo I've ever taken). Today I saw a third forktail species, Ischnura posita, the Fragile Forktail. The male is a very handsome fellow, with stunning green eyes (black on top), a black thorax marked by two interrupted stripes (Dunkle characterizes them as "a a pair of upside-down exclamation marks"), and a long, mostly black abdomen with most segments marked by green rings right where it meets its neighbor: I've been hoping to catch a glimpse of this fellow for quite some time; ever since I got my two damselfly guides this year (the 2011 Paulson guide to Eastern dragon- and damselflies, and the 1990 Dunkle guide to Florida damselflies). It's just a very good-looking bug! Here's another angle for those of you who can't quite get enough of him: Look around your yard; see what you find!

New backyard bug: Euphoria sepulcralis

I first noticed a curious little beetle the other afternoon; I was out looking for bees and wasps, and it did exactly what bees and wasps tend to do: make a "beeline" for a flowerhead, then settle in on it and gather pollen or nectar. So of course I assumed it was a bee at first, since it was doing what bees do, and it was hairy and it made a sort of buzzing sound in flight. On closer inspection, though, it turned out to be much boxier than a bee, it had hardened wing cases (all beetles have these; they are known as elytra), and it had the most interesting antennae (the "feathery" shape of these antennae is described as lamellate). Here it is inspecting one of the weedy flowers (Bidens alba, "Spanish Needles") I like to keep around in case pollinating insects want to come by (One thing that might jump out at you in that photo is the rather sickly looking nature of the flowerhead; I'm not sure what causes that, but I have noticed that many [by no means all] of the flowers these guys visit exhibit this same condition): The beetle is a flower scarab beetle (family Scarabaeidae, subfamily Cetoniinae), Euphoria sepulcralis, to be precise. The common name is either Dark or Spangled Flower Beetle, depending on whom you believe. The scarab family is one of the more well-known beetle groups; it's estimated that there are 30,000 species worldwide. The ancient Egyptians saw in the sacred scarab (Scarabaeus sacer) the embodiment of the sun god Khepri; apparently its propensity for rolling a dung ball across the ground, burying it, and having new scarabs emerge reminded them of the way the sun rolls across the sky, departs at night, and reemerges in the morning. According to Yves Cambefort (Beetles as Religious Symbols),
The first scarab worshiped, was probably the bright metallic Kheper aegyptiorum. The decisive symbolism came from the association of the dung ball to the sun: the scarab rolling his dung ball provided an explanation of the sun’s movement in the sky. However, this solution was neither “logical” (where is the scarab in the sky?) nor exclusive: Egyptian culture embraced their old and new beliefs with an equal and non conflicting faith. The capital of the solar religion was the city of On, which Greeks called Heliopolis (“the City of the Sun”). It was probably at On that Khepri, a scarab god of the sun, appeared in the predynastic epoch. Khepri might have been associated with the brilliant Kheper aegyptiorum, (whose name was coined by André Janssens, in 1940) or to the black Scarabaeus sacer, which was more often figured later. Nowadays, only the latter occurs in this region; the former being a more southern species probably due to significant climactic changes since Egyptian civilization. The name Khepri (or Kheperi, or Khepera) means “The Being, The Extant.” The name Khepri is related to other words of the same root, e.g. kheper “to exist, to come to existence” and khepru “transformations, metamorphoses.” Originally, Khepri represented the sun from sunrise to sunset, although the oldest texts describe him setting in the western horizon at dusk. He quickly lost some importance, and became confined to the associative role with the rising sun, which he maintained throughout the entire Egyptian civilization. He is represented as a man with a scarab topping or replacing his head:
Flower scarabs, also known as rose chafers, flower chafers, and flower beetles, represent only a small percentage of the scarab species (only about 4000 species worldwide, and only 20 in the United States, although there are about 105 when you include Canada and Northern Mexico). They are among the more colorful of insects, as this image from Wikipedia demonstrates: Compared to these gaudy creatures, Euphoria sepulcralis is downright drab, with its dark brown ground color and ivory squiggles. (Pinned specimens look almost black, perhaps accounting for the specific name sepulcralis, of or related to the tomb.) It does have some nice golden hair that is quite pretty in the right light; in fact, that's probably another reason I mistook this guy for a bee at first glance (FYI, there is another, even more bee-like flower beetle, called—go figure—Bee-like Flower Beetle, Trichiotinus piger. From trichion, Gr. diminutive of hair, and piger, Latin for slow, lazy, reluctant, slothful): Furthermore, E. sepulcralis occurs in great enough numbers that they can become agricultural pests; the lists of foods they like is quite long. (I first noticed this beetle on Tuesday and now, Friday, I've probably seen a dozen, sometimes 4 or 5 at once on my weedy flowers; I can imagine some poor farmer trying to keep his corn safe!) According to the UF "Featured Creatures" web page for this species,
DPI records for Florida include many for those hosts [roses and corn], with annotations such as "10-15 beetles per ear of corn." Records also suggest it can be a pest of mango and avocado in South Florida, where large numbers of the beetles destroy the flowers and thus reduce the number of fruits produced. There are also records of the beetles invading bee hives and damaging combs.
There's a mango tree down the street with what looks like millions of flowers; I suspected that was what was pulling these little guys into the neighborhood, but when I went down to look, I found lots of bees and only one or two beetles. Of course, from ground level, it was pretty hard to see much more than the bottom-most layer of flowers; there could have been dozens crawling around up there rather than the one I got a picture of: The presence of these flower beetles, for whatever reason they're here, is most likely what is attracting a parasitic wasp (a scoliid of indeterminate species) that, as far as we know, uses these little guys as prey items: I'm told by people who know that this individual is a stray from the West Indies (Campsomeris dorsata) and I should keep a close eye out for more of them. The red markings indicate that it's a female; I saw what could be a male a day later, but there's no way to distinguish the possible West Indian vagrant from the fairly common North American species C. plumipes, from a photo: Although these are large wasps, and not particularly uncommon, very little is known about their biology beyond the fact that they parasitize the larvae of scarab beetles. Another species that enjoys the presence of these fairly clumsy fliers include the curly-tailed lizards (Leiocephalus carinatus, a Bahamian species introduced to Florida in the 1950s) in my front yard. As I was mowing the weeds the other day, I saw one of these beetles depart from a flower in haste. Since this was before the "infestation" began, I was just getting ready to run inside and get my camera when I saw that it was careening right toward a lizard who, sure enough, ran a few steps and chomped it down. Nature, red in tooth and claw, right here in my yard! To be honest, though, I don't think it takes much skill to prey on these clumsy beetles. I've seen them embedded so hard in a flower head that it would take considerable force to pull them off. I've even seen them just clinging on to a stem, dead as doornails.  

New backyard bug: Loxa flavicollis (probably)

If you live in south Florida, you probably have a pool. And if you live with little ones, you probably have a fence screening that pool from unwanted incursions by unwary feet. And if you're interested in nature, you'll soon discover that the fence does a remarkable job of collecting specimens, not just of dead leaves and other windblown wrack, but live specimens of new and exciting bugs (mostly bugs, a few dipterans, a lepidopteran or two) for a backyard naturalist. Today's example ( a true bug) is a large and relatively conspicuous member of the family Pentatomidae (400 genera and some 5,000 species worldwide): Loxa flavicollis (Drury, 1793). The body is almost an inch long (around 20mm), and nearly as wide, with interesting "horns" projecting out from the "shoulders," and a long series of "teeth" along the front edge of the pronotum: The large, upward-pointing eyes, seen more clearly in the view below, remind me of a flounder or halibut: I've seen other images of this bug on the web, and the shoulder spines are reddish; I'm not sure whether that comes with age or whether it's a sex-marked difference, but our bug certainly did not have much red in the pronotum. L. flavicollis, like all pentatomids, is in the large and interestingly diverse order Hemiptera, the "true bugs." According to Thomas Eisner, one of the most entertaining of entomological writers (and one of the ones we'll miss the most, as he died in March of this year, see the obit in the NY Times),
The mouthparts of hemipterans characteristically are formed into a rostrum or proboscis, specialized for fluid uptake. A number of hemipteran families, notably the Coreidae, or leaf-footed bugs, and the Pentatomidae, or stink bugs, have defensive glands from which they eject strongly odorous fluids when disturbed.
Eisner made his living analyzing the defensive behaviors and secretions of insects so he's quite familiar with the chemical makeup and application techniques of this group of insects. The passage above is from one of his last books, Secret Weapons; he also writes about this family of insects in his other great recent work, For Love of Insects:
The beak contains two channels, one for the uptake of food, the other for the output of saliva. Hemipterans have diverse feeding habits. Some are insect killers, a few are bloodsuckers, and the majority, like most Pentatomidae, are plant feeders. All imbibe liquids only.... Stink bugs derive their name from the defensive secretion they eject when disturbed. In the immatures (the nymphs) the glands open on the dorsal surface of the abdomen, an area which in the adult is covered by the wings. Not surprisingly, therefore, adults have a different glandular arrangement. They possess a single large gland, situated midventrally in the thorax, with two separate openings on the sides of the body just above the legs.
If you click on the photo below, you might be able to make out a light dot or divot on the "belly" of the bug, just between and above the second and third pair of legs; I'm not sure (since I didn't realize it would be important until after the bug had left), but I think that's the "stink gland" opening: According to Eisner, most stink bugs (and I presume this one is no exception) "can discharge separately from the right and left gland openings and they tend to restrict their discharge to one opening if the disturbance is unilateral" (Eisner 2003, 233). I, being slightly entomophobic despite my fascination with bugs, haven't really put this ability to the test, nor did I when I encountered this specimen. If I had, presumably I would have said something like "ewwww,those simple straight chain aldehydes and ketones are stinky!" Back when I was a lad in Sylmar, California (home of the '71 quake), the black "stink bugs" (actually darkling beetles, Tenebrionidae) at our elementary school would stand on their heads and discharge when sufficiently messed with; I hadn't gotten around to reading Eisner's work, so I didn't know how to appreciate the smell back then. But smelling it as I did then, I had very little desire to repeat the experience now that I have read my Eisner. So our stink bug from the fence was able to rest, in peace except for a camera lens pointed his way now and then. Eisner's discussion of the defensive secretions of pentatomids occurs in the context of spiders' ability (or lack thereof) to distinguish prey items. The two examples he chooses are familiar Florida spiders: our famous "banana spider," Nephila clavipes, and the silver orbweaver, Argiope florida. The silver orbweaver apparently treats stink bugs the same way they treat other insects with noxious defenses: it wraps 'em up, spinning 'em lengthwise, without making the bug nervous enough to discharge (!), so that only when it sinks its fangs in does the bug release, futilely, its defensive arsenal. Not one single stink bug ever escaped from Eisner's Argiope spiders. The banana spider, on the other hand, while fully capable of noticing that these bugs needed to be handled differently, had a different, and somewhat less successful hunting style. It always bites its prey first, rather than wrapping it up and immobilizing it. Nevertheless, these spiders did always try to position the bug so that its stink jets pointed away from the spider, but it wasn't always successful, and got sprayed. What's more, if it succeeded in spraying the spider thoroughly enough to give it a moment's respite, the chemicals in the stink juice actually helped the bug dissolve the spider silk and make good its escape! The vast majority of bugs wound up eaten anyway (only 5 of 29 bugs eventually got away), but it is interesting to know that the same stinky chemicals that make the spider back off are also capable of disrupting the integrity of the spider's silk. Eisner's book has some illustrations that I found rather interesting: Does the unidentified pentatomid bug on the left of Eisner's page look familiar? I can't be 100% certain, since I haven't found the paper on which the popular account in For Love of Insects is based, but to me it looks an awful lot like our Loxa! Here's a closer look: See those serrations on the fore-edge of the pronotum? See the shoulder prongs (not very clearly)? I would bet that we're looking at the giant stink bug that I found on my pool fence the other day. What clinches it for me are the big eyes and the shape of the "mouth"; most of the other stink bugs have small little eyes and a tiny beak, but Loxa is huge (relatively speaking, of course).
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