Category Archives: Insects

Image Gallery: Okefenokee Swamp

 January 3, 2015

My somewhat serious resolution for the upcoming year is to increase the frequency of Volusia Naturalist posts.  To that end, I’m initiating the year with a new type of post – an image gallery.  For those times when I don’t have much to say, but want to share some photos of my adventures.

The photos in this set were taken over several days just before the new year.  All of the photos are hyperlinked to larger versions.  We spent most of our time in the Fargo area, at Stephen Foster State Park, with one afternoon trip to the east side of the Okefenokee at the Suwannee Canal Recreation Area, near Folkston.

A gray morning in the Okefenokee Swamp.  This is in Stephen Foster State Park, on the west side of the Okefenokee

A gray morning in the Okefenokee Swamp. This is in Stephen Foster State Park, on the west side of the Okefenokee.

The habitat surrounding the swamp is overwhelmingly dedicated to 20-year rotation timber farming.   This includes a significant acreage in Okefenokee NWR.  This is a tract of young slash pines that have been thinned and burned.

The habitat surrounding the swamp is overwhelmingly dedicated to 20-year rotation timber farming. This includes a significant acreage in Okefenokee NWR. This is a tract of young slash pines that have been thinned and burned. The profuse pale fuzzballs are seed heads of Pityopsis graminifolia.

This Google Earth image shows part of the entry road through Okefenokee National Wildlife Refuge (177).  The Suwannee river near its origin in the Okefenokee is above the road.  Notice that nearly all of the habitat that isn't wetland is covered by plots of timber at various stages of the harvest cycle.

This Google Earth image shows part of the entry road through Okefenokee National Wildlife Refuge (177), leading to Stephen Foster State Park on the western side of the refuge. The Suwannee river near its origin in the Okefenokee is visible above the road. The long straight line in the NE quadrant is the Suwannee River Sill, a several-mile long levee built in the 50’s to control outflow of water from the swamp into the Suwannee. This was an attempt to reduce fire frequency in the swamp during dry years by keeping more water in it. It was a failure. Notice that nearly all of the habitat that isn’t wetland is covered by plots of timber at various stages of the harvest cycle.

Alligators were out  basking on this gray day.  These beasts are in the canal paralleling the Suwannee River Sill.

Alligators were out basking on this gray day. These beasts are in the canal paralleling the Suwannee River Sill.

Great blue heron in the swamp.  Notice the fire-scarred trunks in the background; many of the plant communities in the swamp are fire-maintained.

Great blue heron in the swamp. Notice the fire-scarred trunks in the background; many of the plant communities in the swamp are fire-maintained.

The canal leading from the boat basin in Stephen Foster State Park to the Billy's Lake section of the middle fork of the Suwannee River.

The canal leading from the boat basin in Stephen Foster State Park to the Billy’s Lake section of the middle fork of the Suwannee River.

White-tailed deer were common and tame around the cabins at Stephen Foster State Park.

White-tailed deer were common and tame around the cabins at Stephen Foster State Park.

Red-shouldered hawks were abundant, many hunting the the grassy shoulders of the entry road.

Red-shouldered hawks were abundant, many hunting the the grassy shoulders of the entry road.

Sweetgum

Sweetgum

There were only a few hours of decent sun, on Tuesday afternoon, during the 3 days we were there.  This longleaf pine forest with cane understory is from the Suwannee Canal Recreation Area, on the east side of Okefenokee.

There were only a few hours of decent sun, on Tuesday afternoon, during the 3 days we were there. This pine forest with cane understory is from the Suwannee Canal Recreation Area, on the east side of Okefenokee.

Longleaf pine forest

From the Swamp Wildlife Drive in the Suwannee Canal Area.

A magnificent 3/4 mile boardwalk into Chesser Prairie are of the Okefenokee provides stunning views of this landscape still showing the effects of the 2011 Honey Prairie fire, which was allowed to burn.  Charred posts from a previous boardwalk are still present.

A magnificent 3/4 mile boardwalk into the Chesser Prairie area of the Okefenokee provides stunning views of this landscape still showing the effects of the 2011 Honey Prairie fire, which was allowed to burn. Charred posts from a previous boardwalk are still present.

Chesser Prairie, from the boardwalk.

Chesser Prairie, from the boardwalk.

Eastern phoebe from Chesser Island.

Eastern phoebe from Chesser Island.

Way too distant shot of a male northern harrier, from the boardwalk.  I don't see male harriers often, though females and immatures are common in winter in Florida.

Way too distant shot of a male northern harrier, from the boardwalk. I don’t see male harriers often, though females and immatures are common in winter in Florida.

Pig frog?  Active in the last week of December.   Ranids in Pennsylvania can only dream about that shit.

Pig frog? Active in the last week of December. Ranids in Pennsylvania can only dream about that shit.

Interesting assemblage of insects in the unwet portion of a water lily leaf.  There's a little water strider (Gerridae) in the notch, a small fly (Ceratopogonidae?) above it, and a "herd" of what look like some kind of leafhopper or planthopper nymphs.

Interesting assemblage of insects in the unwet portion of a water lily leaf. There’s a little water strider (Gerridae) in the notch, a small fly (Ceratopogonidae?) above it, and a “herd” of what look like some kind of leafhopper or planthopper nymphs. You have to click and see this at maximum resolution to see any detail in these tiny insects.

The diversity of fungal structures in this rotting branch was impressive.  I have no idea how many species of fungi are visible here.

The diversity of fungal structures in this rotting branch was impressive. I have no idea how many species of fungi are visible here.

Swamp doghobble, Eubotrys racemosa.  These are young flowering spikes that will bloom sometime in early spring.

Swamp doghobble, Eubotrys racemosa. These are young flowering spikes that will bloom sometime in early spring.

The last afternoon we were there produced the best light of the trip.  This shot of the Okefenokee from the boardwalk at Stephen Foster State Park was taken in late afternoon, as the window of sunshine was getting ready to close.

The last afternoon we were there produced the best light of the trip. This shot of the Okefenokee from the boardwalk at Stephen Foster State Park was taken in late afternoon, as the window of sunshine was getting ready to close.

Golden afternoon light can make any shot look decent, but with this kind of view, it's like taking candy from a baby. Which I've never done.

Golden afternoon light can make any shot look decent, but with this kind of view, it’s like taking candy from a baby. Which I’ve never done.

Lovely lethal lynxes

Peucetia viridan_08152014-12_Tiger Bay RR

September 28, 2014

I’ve always been kind of partial to spiders, though at the same time just a bit intimidated by them.  Although the vast majority of North American spiders are of no significant threat to people, the idea of catching a big orb-weaver in the face when I’m in the field still creeps me out if I think about it.  My real introduction to spider biology at anything other than an extremely superficial level came when I first began grad school at UF, and became friends with an arachnophile, Craig Hieber.  Much of what I know about Florida spiders I learned from Craig, and though I can’t say for certain that he was the one who first introduced me to the green lynx spider, I think there’s a pretty good chance he did.  UF Zoology at that time was a hotbed of spider research – faculty members John Reiskind and John Anderson both did research on spiders, and mentored a number of grad students doing their master’s or doctoral research.  Even H. Jane Brockmann, always one of my favorites among the faculty (“do you people say bloody over here?”), got in on the spider action, and her student Linda Fink produced some splendid papers on reproduction and defense by green lynx spiders as an outcome of her master’s thesis.

My friend Craig Hieber (Charlie White in back).

My friend Craig Hieber (Charlie White in back).

Green lynx spiders, Peucetia viridans, are one of the most common Florida spider species.  They prompt the greatest number of requests for identification by the arthropod experts at the Florida State Collection of Arthropods of any spider species in Florida.  Commonly found in ruderal (disturbed) habitats and edges, particularly among flowers in the late summer and fall, I’ve known about their abundance for some time.  When I first moved to my current home in DeLand six years ago, the gardens I planted were loaded with lynxes.  More recently, since I’ve begun spending a lot of my field time ode-cruising, I’ve been struck again how incredibly common they are.   Green lynxes can be pretty cryptic as they spend large amounts of time motionless amidst an inflorescence waiting for some clueless victim to make the mistake of a lifetime, but once you’ve developed a search image, you can’t help noticing them.

Peucetia viridan_09132014-02_L George CA

A male lynx spider, identifiable by the extensions from his palps.

They are so abundant in some habitats, including agricultural fields, that they are an effective biological control agent against some agricultural pests, particularly the many species of noctuid moths that oviposit and feed as larvae on crop plants.  The good that lynxes do by reducing herbivory on crop plants is counteracted somewhat by the number of beneficial insects they consume along with the pests.  Bees, wasps, butterflies and skippers, syrphids and other types of flies… the list goes on and on. Lynx spiders seem to be very opportunistic predators who will take just about any type of insect prey that they can get their fangs on.

With geometrid moth prey

With geometrid moth prey

 

Honeybee prey

Honeybee prey

Tiphiid wasp (Myzinum sp.) prey

Tiphiid wasp (Myzinum sp.) prey

Stiletto fly (Therevidae, Penniverpa sp.)  prey

Stiletto fly (Therevidae, Penniverpa sp.) prey

Tiger moth (Halisidota sp) prey

Tiger moth (Halisidota sp) prey

Ladybeetle (Harmonia axyridis) prey

Ladybeetle (Harmonia axyridis) prey

Monarch caterpillar prey

Monarch caterpillar prey

Crabronid wasp prey

Crabronid wasp prey

And what lovely fangs (chelicerae) they have.  Members of the family containing the lynxes, the Oxyopidae, are distinguished by their relatively tall clypeum (the portion of the “face” between the eyes and the chelicerae) and elongate chelicerae.  Looking at a lynx spider head-on makes me think of an old, droopy-faced wizard.  The Oxyopidae is not a huge family – a bit over 400 species in 19 genera worldwide, in Florida they are represented by only a few species in two genera (Peucetia and Oxyopes).  I’ve never seen any of the Oxyopes species, but I’ve seen more lynxes than you can shake a snake hook at.  They are ubiquitous at this time of year.

The high clypeum, big chelicerae, spiny legs, and unusual eye arrangement are all characteristic of the Oxyopids.

The high clypeum, big chelicerae, spiny legs, and unusual eye arrangement are all characteristic of the Oxyopids.

Finding them isn’t hard.  I’ve seen them referred to in one source as “Inflorescence spiders”, and that is spot on.  If you want to find lynxes, look for them on the inflorescences of a variety of weedy plants, including many composites.   Because they are so cryptic, it helps to look for particular irregularities in flower clusters, like an out-of-place green lump in the midst of the flowers, or the translucent spiny legs projecting out from the flowers.  I’ve lost count of the number of times I’ve found lynx spiders lurking in the background when doing post-processing of photos of other flower visitors.  With their delicate green cephalothorax and abdomen, decorated by whitish chevrons in the larger females, and their nearly transparent multicolored spiny legs, there is nothing to confuse a lynx spider with.  

Early instar lynx on sunflower.

Early instar lynx on sunflower.

On purple thistle, Cirsium horridulum

On purple thistle, Cirsium horridulum

On goldenrod (Solidago sp)

On goldenrod (Solidago sp)

On Hyptis alata

On Hyptis alata

On Pluchea foetida

On Pluchea foetida

On Helenium amarum

On Helenium amarum

On redroot, Lachnanthes carolina, with potential victim

On redroot, Lachnanthes carolina, with potential victim

On pine lily, Lilium catesbaei

On pine lily, Lilium catesbaei

Though I’ve been seeing and appreciating lynxes for years, I was thrilled to recently photograph a male lynx for the first time. Males are slightly smaller than females, but as in most spiders, males are distinguishable from females by their modified pedipalps.  Pedipalps, or palps for short, are the pair of short leg-like appendages extending from the head, with which spiders manipulate  prey or other objects.  Palps are also intimately involved in mating behavior – they are the surrogate penises for males.   Prior to mating, male spiders spin a pad of silk and deposit semen on it and transfer the sperm to receptacles at the end of their palps.  Male spider palps are typically enlarged at the end, sometimes with syringe-like structures and extensions that aid in the process of inseminating the female.  I wonder if female spiders reluctant to mate sometimes give “palp jobs” to persistent males to cool them down?

A male lynx spider, showing the enlarged palps with hook-like extension

A male lynx spider, showing the enlarged palps with hook-like extension. You can click on this image (and most images on the blog) to see more detail in the palps.

Lynx spiders obtain their name from their hunting behavior.  They are ambushers and stalkers, using their acute vision to track and pounce on unwary prey.   I’ve never been lucky enough to see one making a kill, but I have on several occasions watched a hunting lynx make a quick dart towards pollinators approaching the flower they are sitting on.   Just yesterday I photographed one that had just seconds previously captured a small darkly-colored grass skipper; the lynx had her fangs embedded in the skipper, and it slowly unfurled and then recoiled it’s proboscis as the venom took hold.  At one point the struggling skipper forced the lynx to release her hold on the plant, and the spider and her skipper prey dangled from a few silk lines, spinning in the faint breeze until she regained her purchase.

Skipper prey

Skipper prey

Did someone say badass?  Lynx spiders seemingly know no fear.  They’ll take just about any prey they can inject their venom into, including some insects as large or larger than the spider.  Occasionally, however, the tables are turned and insects that could be taken as prey take the spider.  Many species of solitary wasps provision their nests with paralyzed spiders to feed their developing offspring, and lynx spiders are among the victims.

Leaf-footed bug (Leptoglossus phyllopus) prey

Leaf-footed bug (Leptoglossus phyllopus) prey

Antlion prey

Antlion prey

Dragonfly (Libellula sp) prey

Dragonfly (Libellula sp) prey

On a number of occasions, I’ve seen lynx spiders with prey being victimized by another arthropod colleague, though not with such drastic results as their interactions with spider wasps.   Lynx prey items are sometimes attacked by hemolymph-sucking ceratopogonid flies (midges) as the spider is sucking out the liquefied prey contents.   I don’t know whether the midges also attack the lynx, but they do parasitize other adult arthropods, such as dragonflies.

This leaf-footed bug (Leptoglossus phyllopus) being eaten by the spider is also hosting a big crowd of ceratopogonid flies sucking on the hemolymph.

This leaf-footed bug (Leptoglossus phyllopus) being eaten by the spider is also hosting a big crowd of ceratopogonid flies sucking on the hemolymph.

Do the midges parasitize the lynx as well?  Who knows?

Do the midges parasitize the lynx as well? Who knows?

 Aside from their general ferociousness and take-no-prisoners attitude, lynx spiders show a gentle side.  They are excellent mothers.  Linda Fink’s research while at the University of Florida revealed that females guard their egg cases (cocoons) for several weeks after they lay the eggs, and that this defensive behavior significantly increases survivorship of cocoons when compared to experimentally manipulated cocoons from which the female had been removed.  Ants seem to be the biggest threat; the female lynx will directly attack the ants, though on occasion they will chomp down on a leg and not release their grip even after death.  Linda observed lynx spiders in some instances sacrificing a leg (autotomy) to rid themselves of the dead hanger-on.   Their maternal devotion doesn’t protect the eggs from one other threat, though – parasitic mantidflies (Mantispidae) that lay their eggs in the spiders’ cocoons were equally common in both Linda’s control (mother remained) and experimental (mother removed) treatments.

The mantid fly Zeugomantispa minuta.

The mantidfly (Family Mantispidae, Order Neuroptera) Zeugomantispa minuta.

Linda even documented a new defensive behavior for lynxes while doing her research on maternal care – they spit venom in the direction of their enemy.   Although there is an entire family of spiders that specializes on spitting their gooey silk-containing venom cocktail on their prey to immobilize them (the Scytodidae), green lynx spiders are the only oxyopids known to defend themselves in this way.

A fat female who will soon produce an egg-filled cocoon

A fat female who will soon produce an egg-filled cocoon

If the standard defensive measures don’t work, lynx mothers will relocate their cocoon to another plant.  But they do so in a unique way; they don’t carry the cocoon to its new site, as some other spiders do, but instead reengineer its attachment.   They establish new suspensory silk lines anchoring the cocoon to the foliage of a nearby plant, and then cut the silk lines attaching it to its current host.  The cocoon swings over to its new site and the female then secures it with more silk. 

Lynx and beautyberry

Lynx and beautyberry

She stays with the developing eggs in the cocoon for several weeks until they hatch, sometimes refraining from feeding and starving herself in the process.  The cocoon can contain 25-600 eggs, averaging about 200.  Whether the female refrains from feeding or not, she will die sometime during the fall, and her early-instar offspring will overwinter, maturing and reproducing themselves about 300 days later. 

Baby lynx on Gaillardia

Baby lynx on Gaillardia

My next photographic goal – obtain a cocoon or two, with attending female, and keep them in captivity until the little dudes hatch.  Is there anything more adorable than a batch of a couple hundred little lynx spiderlings being doted on by a loving mother?  I doubt it.

References

Fink, L.S. 1986.  Costs and benefits of maternal behaviour in the green lynx spider (Oxyopidae, Peucetia viridans).  Animal Behaviour 34(4):  1051-1060.

Fink, L.S. 1987.  Green Lynx Spider Egg Sacs: Sources of Mortality and the Function of Female Guarding (Araneae, Oxyopidae).  Journal of Arachnology 15(2): 231-239.

 

 

Of orthops and odes

Conocephalini_08302014-01_Heart Island DC

September 20, 2014

I’m undergoing a seismic shift in my natural historizing, it seems.  Normally this time of year I’d be out in the field on any morning I can, frantically seeking migrant songbirds (and often failing).  Thus far this migration season, which began back in early August for me, I’ve spent virtually no time seriously birding.  I’ve been out several mornings with birds in mind, but when avian action was not readily forthcoming, I switched my focus to a more attainable target – insects and other spineless beasts.  Two reasons: I could find them, and I could photograph them.

Eastern amberwing, Perithemis tenera, on Carphephorus odoratissimus

Eastern amberwing, Perithemis tenera, on Carphephorus odoratissimus

I have this bizarre compulsion that taints everything I do when digging on the natural world – I have to take photographs of whatever I’m seeing, if at all possible.  It’s an affliction really, that impacts my ability to just chill the fuck out and groove on nature.   Close friends who come to visit me and sit on my porch and watch birds with me have remarked on this on numerous occasions.  Do you really need more photographs of northern cardinals?  Point taken.

Blue dasher, Pachydiplax longipennis

Blue dasher, Pachydiplax longipennis

Nonetheless, as some great sage (who I may be related to) once said, it is what it is.  One of the many benefits of teaching college is the extended vacations, which allow me to devote most of my energies to some goal I find hard to accomplish during the semester.  This past summer, my main goals were to increase my fluency in field botany and to learn to find, identify, and photograph dragonflies and damselflies, the odes of the title (a bug geek term for insects in the order Odonata).   In pursuit of odes, I’ve rediscovered my fascination with hexapods of all sorts; insects are so unendingly diverse and intriguing that one could spend a lifetime studying the natural history of insects in Volusia County and still only scratch the surface.  On the worst birding days, it’s very rare that you can’t find some interesting arthropods to ponder.

Twin-striped forceptail, Aphylla williamsoni

Twin-striped forceptail, Aphylla williamsoni

So odes have been a primary focus for me the last several months.  But photographing them requires getting fairly close, if one is using a typical macro lens in the range of 100-200mm focal length.   Plus, I do a lot of observation and photography from the car, which allows me to cover way more habitat than I ever could awheel.  (Is that a word? Afoot, awheel – why not?) Further, dragging my chair out of the backseat and getting self-mobile takes a couple of minutes, so even if the substrate is doable for me, getting out for every photo op just isn’t a workable strategy for me and those of my ilk.  Driving close enough to a perched dragonfly to get a reasonable image with my usual insect lens, a 150mm Sigma macro, is pretty tough to do.   Dragonflies can be pretty wary beasts. For several years I’ve tried sporadically to take “macro” photos of some larger inverts, like odes, with my main bird lens, a 150-500 Sigma.   But at the closest focus distances, I was having a lot of trouble consistently getting sharp images.   Sometimes razor, sometimes vaseline.

Eastern pondhawk, Erythemis simplicollis, with prey, on chalky bluestem

Eastern pondhawk, Erythemis simplicollis, with prey, on chalky bluestem

My breakthrough with odonate photography from the car came in August, when a female mud dauber began building a nest in the tracks of my sliding glass door, and I decided to try and photograph her.   She was too high for me to get decent shots with my standard macro, and the angle would be too steep if I shot from right underneath her anyway.   I remembered a 20-year old lens I had relegated to the photo gear graveyard soon after I went digital and got the big Sigma zoom.  The old lens was also a Sigma, a 400mm 5.6 lens that was the first refractive lens I used seriously for bird photography.  For a couple of decades I had wasted my time trying to do bird photography with one of the horrid old mirror lenses, which were cheap for their long focal lengths, but generally produced rather low-quality images.   A coincidental meeting at Lake Woodruff NWR with the great bird photographer Artie Morris, who I’d never heard of at the time, enlightened my world.  From a distance, I was blown away by the gigantic camouflaged 600mm lenses and Gitzo tripods he and his companion were toting (big-time big lens envy), so when we passed I chatted them up a bit.  When I showed Artie my mirror lens rig, he graciously avoided snorting in derision, and suggested I upgrade to a refracting 400 f 5.6.  He took a body with his 400 f5.6 Canon lens (his “toy lens”) from around his neck and allowed me to look through it.  I was sold, and bought the Sigma 400 soon after.

The immodest grasshopper, Melanoplus impudicus, eating flowers of Liatris tenuifolia

The immodest grasshopper, Melanoplus impudicus, eating flowers of Liatris tenuifolia

I used that lens for years when I did slide photography, and it was a splendid lens.  Incredibly slow 1st-generation autofocus, with no internal motor, but I never used that when I shot with a film body.   But it was renowned for its sharpness, and it was sold as a “Macro” lens.  Not really, but it would focus close enough to get to a 1:3 reproduction ratio, which is pretty decent for a lens with that much reach.  Perfectly suitable for larger insects.  So it occurred to me to drag that old relict out, set it up on a tripod with a soft-boxed flash, and focus on the dauber’s nest, waiting for her regular returns.  I was impressed again by the image quality, and the Sigma 400 became my lens of choice for insect photography from the car.  I doesn’t have any of the vibration reduction systems typical of long telephotos these days, so handholding it and getting critical sharpness are mutually exclusive.  I normally shoot from a beanbag on my car door when doing automotive photography, and that setup is rock solid.

Schistocerca damnifica, the mischievous bird grasshopper

Schistocerca damnifica, the mischievous bird grasshopper

So that’s how I shifted my focus from cruising for birds, which can be abysmally slow in the summer, to cruising for dragonflies, which is usually exactly the opposite.  Ode cruising, I call it.  And in the process, I began keying in on the other big arthropods that can be spotted and photographed while ode cruising.  As it turns out, the most commonly observable and shootable big insects I see are grasshoppers and katydids, of the order Orthoptera.  Orthops for short.

The olive-green swamp grasshopper, Paroxya clavuliger

The olive-green swamp grasshopper, Paroxya clavuliger

So these days, I get more excited about the idea of photographing orthops and odes more than the prospect of photographing birds.  Both dragons and hoppers are amazingly intricate and photogenic insects, but I’ve been struck repeatedly by my blatant taxonomic bias – I’d far rather find and photograph odes than I would orthops.  Notwithstanding the fact that orthopterans include some of the most striking and beautifully colored insects in the world, and at the other end of the extreme orthops that are exquisitely cryptically colored to blend with their surroundings, an equally astounding feat of adaptation.  Still, for me, dragonflies are the shit.   It’s an incredibly overused metaphor, but I’ll use it anyway – dragonflies are the attack helicopters of the insect world.  I remember seeing Coppola’s opus Apocalypse Now for the first time (and many times thereafter), marveling at the incredible cinematography.  While watching with mouth agape as Colonel Kilgore and the air cavalry attack the point where the waves break in both directions (“Charlie don’t surf!) to drop Willard and his PBR crew into the mouth of the Nung, I remember thinking that the Hueys in slow motion were like nothing so much as giant dragonflies.  The precision and power of odonate flight is awesome, and they are some bad, badass predators.   Seeing one ode munching on another nearly its own size makes me very happy they don’t get any bigger than they do.  Magnificent animals.

Halloween pennant, Cellithemis eponina.  An absolutely gorgeous insect.

Halloween pennant, Cellithemis eponina. An absolutely gorgeous insect.

On the other hand, orthops are the heavy equipment of the insect world, to me.  Generally slow, lumbering, inoffensive and unaggressive – all fine qualities for an animal, but not as likely to arouse my intense awe as those of rapid and wary predators.  But orthops are charming, colorful and diverse beasts that frequent weedy roadsides, so how could I pass them up?

Atlantic grasshoppers, Paroxya clavuliger, procreating.

Atlantic grasshoppers, Paroxya atlantica, procreating.

The pursuit of odes provides me a whole new treasure trove of lifer organisms to see and photograph, like this Amanda's pennant (Cellithemis amanda) I saw for the first time a week ago

The pursuit of odes provides me a whole new treasure trove of lifer organisms to see and photograph, like this Amanda’s pennant (Cellithemis amanda) I saw for the first time a week ago

And every now and then, I see other cool critters, like spiders, and owlflies.  I may be more taken with the spiders than I am with the odes these days.   But that’s another post.

Ululodes florida_09162014-07_Tiger Bay RR

The Florida owlfly, Ululodes floridanus

One of the unanticipated benefits of immersing myself into new taxa to explore and photograph is that it delivers a big dose of humility.  It doesn’t take long to realize how little I actually knew about them before, and how much there is in front of me to learn.  And that’s cool.

Blue dasher obelisking.  In obelisking behavior, the ode points its abdomen directly at the sun to prevent overheating

Blue dasher obelisking. In obelisking behavior, the ode points its abdomen directly at the sun to prevent overheating

Katydid on Centrosema

Katydid on Centrosema

 

Things didn't work out so well for this skimmer.  That's a green lynx spider (Peucetia viridans) that has ambushed this ode from an inflorescence of ten-angled pipewort, Eriocaulon decangulare

Things didn’t work out so well for this skimmer. That’s a green lynx spider (Peucetia viridans) that has ambushed this ode from an inflorescence of ten-angled pipewort, Eriocaulon decangulare

Schistocerca grasshopper nymph kicking off his old skin

Schistocerca grasshopper nymph kicking off his old skin

Common and stunningly beautiful - golden-winged skimmer, Libellula auripennis

Common and stunningly beautiful – golden-winged skimmer, Libellula auripennis

 

Looking for a miracle

 August 4, 2014

Watching this Sceliphron mud dauber provision and seal off her sixth cell inspired me to document her building of Cell 7.

Watching this Sceliphron mud dauber provision and seal off her sixth cell inspired me to document her building of Cell 7.

I’m one of those paganistic sorts whose main source of spiritual enrichment is my observation of and interaction with the natural world. Forget about talking snakes and burning bushes – I witness the miraculous every time I’m in the field. In the last day, I’ve watched a miracle unfolding without even leaving my house.

A couple of weeks ago a female black-and-yellow mud dauber, Sceliphron caementarium, began building a nest in the frame of my sliding glass door. To get there, she had to come into my glassed lanai while the glass panels were open. Once I noticed her building her first cell, I began leaving the glass room open as much as possible to allow her to continue her work. I think mud daubers are one of the first insects I learned to identify as a kid, before I had any real organized knowledge of nature. They are that common. Everyone knows them. I’ve always thought that the common Sceliphron in Florida, S. caementarium, is a particularly elegant looking wasp, and I knew the basics of their reproductive biology, but I’d never had the opportunity to watch one build at length.

Sceliphron caementarium, the black-and-yellow mud dauber.

Sceliphron caementarium, the black-and-yellow mud dauber.

For the next couple of weeks, my patio female added several more cells, and I frequently saw her flying in and out of the patio carrying mud balls. Yesterday, as she completed the sixth cell, I watched through binoculars from my living room couch as she provisioned the completed cell with a big green spider, and then a few minutes later capped it off with more mud. It was so amazing to watch I decided to set up on her and photograph her as she built, provisioned, and sealed her next cell. It took her between about 5:30 on Sunday evening and noon Monday to complete the task. It was a miracle.

The engineering and architectural feats of hymenopterans, the ants, bees, and wasps, are well known and all are worthy of marvel and awe. The fungus gardens of leafcutter ants, paper wasp and hornet nests, the hives of honeybees – all employ sophisticated design principles to achieve their ultimate goal, production and nurture of the next generation. But these are the works of colonial species, contributed to by dozens-millions of individual organisms. Solitary wasps like Sceliphron are perhaps even more awe-worthy simply because each female is on her own. She builds a stone castle for her children entirely by herself.

Larra bicolor, a deliberately introduced species of wasps that preys on mole crickets.

Larra bicolor, a deliberately introduced species of wasps that preys on mole crickets.

There is a huge diversity of solitary wasps, many of which share a common lifestyle – they build or dig some kind of nursery chamber in which to lay eggs, and then they provision the eggs with paralyzed insects of some sort that will be the larval food source. Cicada killers are one of the more obvious examples, but other provisioning wasps specialize on a variety of prey. Some specialize on caterpillars, others on crickets. Just a couple of weeks ago I found and photographed a beautiful crabronid (in the family Crabronidae) wasp that I had never seen before called Larra bicolor. This metallic black-and-red wasp was imported from South America in the 80’s and 90’s to control populations of non-native mole crickets. That’s how specific they are in provisioning their offspring – they hunt only mole crickets, which they temporarily paralyze with their sting. They lay an egg on the cricket, and when it recovers, it goes on its merry mole cricket way, now carrying a parasitoid wasp larva that will eat it from the inside out as it develops. Larra bicolor is so specialized in host choice that they attack non-native mole crickets almost exclusively; they ignore the native species of mole cricket, which as it turns out are attacked by a different, native species of Larra.

Liris wasp with paralyzed Gryllus cricket.

Liris wasp with paralyzed Gryllus cricket.

Last week, I saw another cricket specialist wasp in the genus Liris dragging a paralyzed cricket across the hammock floor at Beresford Park. Liris wasps attack only crickets in the genus Gryllus.

Leucage venusta, a common orb-weaver (Family Araneidae) in Florida.  Sceliphron wasps prey on a number of orb-weavers.

Leucage venusta, a common orb-weaver (Family Araneidae) in Florida. Sceliphron wasps prey on a number of orb-weavers.

Lovely Sceliphron is a spider specialist. They provision their nest chambers, or cells, with a mess of paralyzed spiders, which will feed the single larva that hatches in each cell. They exploit a variety of spider species, including both web-building and non-web spiders. But before they can do that, they have to build the chamber. They do this one cell at a time, which is provisioned, oviposited in, and sealed off before the next cell begins. That means that at numerous points some behavioral switch is engaged, and the female abruptly shifts her focus.

Bringing in mud for one of the lower courses.

Bringing in mud for one of the lower courses.

First they must locate a suitable site; the one inside my patio was much lower than most I’ve seen, making it convenient for watching. Once a site is procured, the first switch is thrown, and they begin collecting mud. It seems to be a very consistent form and composition of mud, as the nests are incredibly uniform looking once completed. My female began building Cell 7 a little before 5:30 on Sunday evening, and completed it at about 7:45. During that time, she delivered and installed a new mud ball every 5 minutes or so. She was so regular during most of this time that I actually set my microwave timer for 4 minutes each time she left, and during that time futzed around the house, rushing back to the tripod-mounted camera when the alarm went off. Usually, she would reappear like clockwork within 15-30 seconds after I positioned myself. So to complete one cell she made somewhere between 25-30 mud-gathering trips.

Building the cell wall.

Building the cell wall.

Shaping the clay.

Shaping the clay.

Behavioral switch 2, from mud-gathering to building. The building process is remarkably delicate and precise. She deposits each mud ball on one side of the growing tube, and then manipulates it with her mandibles into a thin ribbon that adds to the length of the cell. The dexterity with which she accomplishes this task is impressive. It takes her less than a minute to form each mud deposit, and then she’s off for more. But interestingly enough, she never leaves immediately after finishing the latest course – she always entered the growing cell first, perhaps touching up the inside seams, and then emerged, usually to wander around the nest for a few seconds before launching into space to gather another mud ball.

She entered the cell after each course was finished before flying away.

She entered the cell after each course was finished before flying away.

Behavioral switch 3. She cycled between mud-collecting and building for the next couple of hours. The last I saw of her on Sunday evening was around 7:45. The females sleep away from the nest; my plan was to be back on the nest at first light so as not to miss the next stage, provisioning. I didn’t know what time that might be. I was an earlier riser than she. I first saw her around 8:15, and then apparently only for a final inspection of the now hardened cell. She spent a minute or so walking around her castle, and then took off.

The cell grows.

The cell grows.

Grooming after completing the lip of the cell.  She often groomed for a few seconds after finishing a course.

Grooming after completing the lip of the cell. She often groomed for a few seconds after finishing a course.

Inspecting the newly-hardened cell at 8:15 in the morning.

Inspecting the newly-hardened cell at 8:15 in the morning.

Behavioral switch 4. She was in hunting mode. Which apparently is not as regular and predictable as mud-gathering. I was hoping she would bring a spider in every five minutes or so, but it wasn’t until after 11 that I first saw her again. She was carrying a rather large green lynx spider, with its legs bent upwards over its back and almost parallel to each other. The wasp somehow did that, apparently, to make transport easier.

She delivers with a big juicy lynx spider.

She delivers with a big juicy lynx spider.

Green lynx spider enjoying happier times.

Green lynx spider enjoying happier times.

Preparing for insertion.

Preparing for insertion.

Behavioral switch 5. Insertion. It took her a minute or so to position the spider and drag it backwards into the cell. Somehow she was able to get it in, legs last, position it inside and then exit herself from the hole. That was the only spider I saw her bring to that cell, though it’s possible I missed other deliveries because of her somewhat rude and inconveniencing loss of regularity. I did see her come back a couple of times and spend several minutes trying to tuck the ends of the protruding spider legs completely into the cell. So as far as I know, that larval wasp has only one spider to feed on, though in some cells there may be several spiders. In the Sceliphron species whose provisioning behaviors have been well-studied, the amount of food supplied for each cell is quite consistent, and based on total mass of the spiders delivered, not volume of the cell or number of individual spiders. So while the wasp is in provisioning mode, she is also keeping track, somehow, of the total weight of spiders she has delivered to that cell. Miraculous.

Come into my parlor, said the wasp to the spider.

Come into my parlor, said the wasp to the spider.

Not as easy as it looks.

Not as easy as it looks.

Dealing with those pesky legs.

Dealing with those pesky legs.

She seemed somewhat befuddled about how to deal with the protruding legs.  So she groomed.

She seemed somewhat befuddled about how to deal with the protruding legs. So she groomed.

Finally, behavioral switch 6. Capping. She seals off the cell by resuming the mud-gathering/buildingcycle. Watching her build the tube course by course was impressive, but seeing her turn that round ball of mud almost instantaneously into a cap of even thickness was even more so. She delivered five separate mud balls to complete the seal, thickening it with each new load, and in the last couple buttressing it to the surrounding cells. And then she looked upon her work and saw it was good. Seriously. After the last buttressing load, she spent what seemed like a longer period of time than usual wandering around her castle inspecting it. I actually thought while she was doing it that she had completed that cell. And she had. It was a bit after noon.

First mud ball forming the cap.

First mud ball forming the cap.

Smoothing the cap.

Smoothing the cap.

Off for more mud.

Off for more mud.

Mud load # 27.

Mud load # 27.

Thickening the cap.

Thickening the cap.

Buttressing the cell.

Buttressing the cell.

She began working on Cell 8 at about 1:30, and is still building the tube as I write this. Which involved another behavioral switch, returning to site-selection mode. I suspect the last inspection period was part of the decision-making process regarding where in the structure the next cell should go.

Sceliphron caeme_08042014-20_620 COC

Sceliphron exhibits a remarkably sophisticated and precise chain of behaviors, most of which must be innate. Once she has completed all of her cells (which can range from less than 10 to over 40), she leaves her castle and offspring on their own. If her babies successfully navigate larvahood, they will emerge from their cells knowing exactly how to do everything their mother did. If they are females, that is. If they are males, on the other hand, all they have to know is how to hang around on the corner like a hoodlum and try to entice a female to accept a load of sperm. The disparity should be troubling and revolting to all decent folk.

Sceliphron caeme_08042014-02_620 COC

Regardless of sex, though, nearly all of the operating instructions for these complex little beauties are encoded in the genes. Which is not to say that they are incapable of learning, and increasing their skill and dexterity with experience –  learning must be involved in some aspects of their behavior. They must find a suitable nest site, and remember where it is and how to return to it from each collecting/provisioning trip. Still, a stunning amount of information must somehow be stored in the form of DNA, the primary function of which is to encode information allowing cells to build specific proteins. So, all of those complex and sophisticated behaviors are ultimately the result of the activities of specific proteins that constitute the major building blocks and functional components of all cells and tissues. And that is truly a miracle.

 

Remembering old friends

Saltbush (Baccharis halimifolia) blooming in the mesic flatwoods of Lake George Conservation Area

Saltbush (Baccharis halimifolia) blooming in the mesic flatwoods of Lake George Conservation Area

November 10, 2013

True fall tends to make me ruminisce (a hybrid mental process involving both reminiscence and rumination), often tending towards the melancholy.  True fall is for me defined by two things:  the point in time when I begin to perceive a significant change in temperature, cross-factored with a decided shift in the bird fauna from the transient migrants towards winter residents.   The indicator event of the latter is for me is the ascendance of the yellow-rumped warblers¸ the fourth wave of migrant warblers, to numerical dominance.  I encountered both those indicators this morning when I cruised Lake George Conservation Area, just west of Seville.  So it’s not surprising that a lot of stuff I experienced today brought back memories.   Most good, some bittersweet.

After a spectacular mackerel sunrise that I was unable to capture on sensor because I failed to follow Skeate’s 6 P’s (prior planning prevents piss-poor performance), I reached the entrance to LGCA at Truck Trail 2 a bit after sunrise.  The spectacular sunrise soon turned to a mostly overcast, dully-colored kind of early morning.   Bird activity was notably lacking at first light.   At my first stop, unproductive for birds, I found a jaundiced-looking lynx spider in a fruiting branch of beautyberry that seemed photoworthy.  As happens nearly every time I do anything related to spiders, I thought of my graduate school friend Craig Hieber, who taught me a significant proportion of what I know about Florida spiders.

Green lynx spider (Peucetia viridans)  on American beautyberry (Callicarpa americana)

Green lynx spider (Peucetia viridans) on American beautyberry (Callicarpa americana)

Craig was a great blond bear of a man, with a huge appetite for life and a big, big heart.  He was also a spider fanatic.  We spent many enjoyable hours in the field cross-pollinating each other with inane trivia from our own area of expertise.  I’ll never forget the time Craig hummed to a Neoscona in its web, and by hitting some particular frequency to which that species is attuned, caused the spider to snap immediately into an alert, forelimbs-raised hunting posture. A revelation for me about spider behavior.  Craig died unexpectedly several years ago, far too young.  I remember feeling like I’d been stabbed in the heart when I first learned of his death.  But I remember him and the cool stuff he taught me all the time.  I think it was Alice Sebold who wrote in The Lovely Bones something to the effect that when you have a memory of someone who has died it means that person’s spirit or essence is near you.  If that’s true, Craig spends a lot of time hanging out around me.

Craig Hieber and a nesting soft-shelled turtle we found on one of our outings.

Craig Hieber and a nesting soft-shelled turtle we found on one of our outings.

Neoscona crucifera, the spider Craig sang to.

Neoscona crucifera, the spider Craig sang to.

The other old friends that I remembered this morning didn’t bring such a mixed bag of feelings.  They were mostly the winter resident birds that have recently begun to dominate the avifauna.  I love seeing transient migrants simply because of their evanescence.  My encounters with the transients are too brief to feel like I really grok them though.  With the winter birds, it’s different.  They are around for a good four to five months.  I get to see them and interact with them over and over again during their winter stay.  And for some of the more common ones, I get more of a visceral feel for what they are and what they do. Whatever the hell that means.

Ruby-crowned kinglet, one of the winter residents that defines the onset of true fall.

Ruby-crowned kinglet, one of the winter residents that defines the onset of true fall.

Yellow-rumped warblers were the most abundant passerines of the morning.  One flock contained several dozen birds.  They just continued to drop out of the skies.  As is typical of my experience with the butterbutts, they are dedicated mobbers, but relatively shy and skittish compared to most other mobbing warblers.  In the large flock, not a one came down from the treetops.  When the occasional bird does approach more closely, the slightest movement is all it takes to send the lot of them scattering for cover.  Still, it’s just very cool to see flocks containing that many passerines again.  One of the things I really like about the winter bird fauna.

Every afternoon from about this time of fall until spring migration, the yellow-rumps move through my yard about an hour or so before sunset.  Flocks of anywhere from a half-dozen to 30 or more will appear from nowhere and glean the oaks and cherries in my yard.  They usually stay a half-hour or so, then move on.  Regular as clockwork.  Where are they coming from, and where are they heading to roost?   They clearly have a schedule to keep.

Yellow-bellied sapsuckers are another winter friend I love seeing again each fall.  I had seen a few sapsuckers in the previous couple of weeks with the Ornithology class, but hadn’t got a chance to watch one at length before this morning.   I don’t think I can say I really grok sapsuckers yet, but I’m getting closer.  Such a recluse, for a woodpecker.  Maybe that’s one of reasons I like them so much – the whole birds of a feather thing.   All of our other woodpeckers are pretty good at making a dramatic entrance when they want to – a big power glide and swoop onto an open trunk is pretty hard to miss.  Sapsuckers may be able to do that, but they don’t seem to want to very often.  They just kind of slip in quietly most of the time, and all of a sudden they are there.   And disappear just as quickly.   Their presence is better judged by their works.  In some habitats, sapsucker drill holes are everywhere.

Yellow-bellied sapsucker at Lake George Conservation Area.

Yellow-bellied sapsucker at Lake George Conservation Area.

Can plants be friends? Hell yes they can.  As the great Zappa once wrote, “Call any vegetable, call it by name. Call one today, when you get off the train.  Call any vegetable, and the chances are good  That the vegetable will respond to you”.   So I was thrilled to see big lavender swaths of my old friend Garberia in the flatwoods this morning.  I think of Garberia as a scrub plant, but there they were in the flatwoods looking happy as clams.   Not only is Garberia a lovely plant as judged by the standards of the pure botanist, it is notable for other less obvious reasons.  It’s a very non-composite-like composite to me, which is especially welcome at this time of year when composites of all kinds are going nuts.  Garberia seems to me to be a composite that would really rather be an ericad.   So it has that going for it, which is nice.

Syrphid fly partaking of the pleasures of the botanical hussy Garberia heterophylla

Syrphid fly partaking of the pleasures of the botanical hussy Garberia heterophylla

But it’s also something of a whore for pollinators.  Anybody will do, it seems.  I have, of course, fallen victim to one of the classic blunders, the most famous of which is “never get involved in a land war in Asia”, but only slightly less well known is never make the assumption that all insects visiting a flower are pollinators.  Still, given the relatively open flower morphology and the long easily accessible stamens and style, it doesn’t seem like total heresy to suggest that most of the flies, bees, wasps, skippers and other butterflies swarming over these lush Garberia flowers might effect pollination to some degree.

Buckeye at Garberia.  Lake George Conservation Area

Buckeye at Garberia. Lake George Conservation Area

Skipper at Garberia.  This was one of the happier skippers I saw visiting the flowers.

Skipper at Garberia. This was one of the happier skippers I saw visiting the flowers.

The highlight of the activity at the Garberia patch was provided by another old friend, a Carolina anole.  This one was creeping around the foliage below the big flower heads, his pie-hole crammed with a skipper he had recently snagged from above.  The stink eye he was giving me as he tried to figure out what to do with his mouthful of chitin suggested that his thoughts towards me weren’t as fraternal as mine towards him.  At least at that moment.

Green anole (Anolis carolinensis) scarfing one of the less happy skippers I saw at Garberia.

Green anole (Anolis carolinensis) scarfing one of the less happy skippers I saw at Garberia.

Color pattern conundrums

October 13, 2013

I had tempered hopes for finding new and interesting migrants when I left home before sunrise Friday morning.   Fall break, a whopping two days, allowed me to forget about classes and go anywhere I desired.

I do most of my birding and natural historizing inland, at sites relatively close to DeLand.   Coastal sites, both on the Atlantic and Gulf coasts, routinely produce higher diversity and abundance of neotropical migrants than do inland sites, but I always feel a little guilty burning gas for longer road trips when cool stuff is surely nearby.   The superiority of coastal sites isn’t surprising given that many of the migrants I’m most interested in follow migratory paths that take them out over open ocean or gulf, and come to land when forced down by storm fronts or local weather systems that  forestall their long-range movements.  So they tend to concentrate along the coasts until conditions improve, during which time they can replenish their fat reserves for the long flight to come.  If conditions are good, many migrants bypass Florida entirely en route to the tropics.

Female American redstart.  Tomoka State Park

Female American redstart. Tomoka State Park

Tomoka  State Park was my primary destination, where veteran bird-bander Meret Wilson had reported some great birds in the preceding week (including a Swainson’s warbler, which would be a lifer for me).   I had misgivings though, as Friday morning followed two nights in a row of clear skies, which tend to favor departure of migrants that have been delayed along the coast.  That apparently was the case on this Friday morning, as Tomoka was mostly devoid of anything other than resident species like northern cardinals and Carolina wrens.  One small flock that included an American redstart, a yellow-throated warbler and a couple of prairie warblers contained the only migrant passerines I found there.

Balduina angustifolia, or Coastalplain Honeycombhead.  Heart Island Conservation Area

Balduina angustifolia, or Coastalplain Honeycombhead. Heart Island Conservation Area

Palafoxia integrifolia, or Coastalplain Palafox. Heart Island Conservation Area

Palafoxia integrifolia, or Coastalplain Palafox. Heart Island Conservation Area

The great thing about natural history and biotic diversity, though, is that there is always something cool going on somewhere.  So mid-morning found me back inland, at Heart Island Conservation Area.  This was the SR11 entrance to Heart Island, just a bit north of the intersection of SR40 and SR11.  The mostly flatwood habitats there were full of fall composites attracting a diversity of nectaring butterflies.  The flora included several of the purple-flowered species, including  Carphephorus corymbosum, a couple of species of blazing star (Liatris spp.), big gorgeous patches of Balduina angustifolia, and a species of Palafoxia I hadn’t seen before.  The biggest attractor for butterflies on Friday morning were the big white-topped asters (Sericocarpus tortifolius;  thanks, CB), some of which produced flowering spikes over six feet tall.  They were buzzing with activity from both butterflies and bees.

Palamedes swallowtail (Papilio palamedes) at Carphephorus corymbosum.  Heart Island Conservation Area

Palamedes swallowtail (Papilio palamedes) at Carphephorus corymbosum. Heart Island Conservation Area

Grass skipper (species undetermined) at Balduina angustifolia.  Heart Island Conservation Area

Grass skipper (species undetermined) at Balduina angustifolia. Heart Island Conservation Area

Butterflies visiting these big composites spanned a huge range in size, from small drab orange skippers to gargantuan tiger swallowtails.   There were also several viceroys at one of the clusters, indicating that there were willows nearby.   Viceroy larvae feed mainly on willows, and the adults don’t seem to wander far from the vicinity of their larval foodplants.   The most exciting lep, to me, nectaring  at the Sericocarpus was a single great purple hairstreak (Atlides halesus), a species that I just photographed for the first time a couple of months earlier.   Hairstreaks are among the smallest of the butterflies, but great purples are giants amongst their confamilials.   And this one was not only in pristine condition, but was very deliberate in his foraging movements, repeatedly visiting the same flower clusters and working slowly from one disc flower to the next.  I spent more than a half-hour tracking this one individual, waiting for him to move close enough to me and position himself appropriately for photos.

Tiger swallowtail female at Sericocarpus.  Females have extensive blue on the hindwing, lacking males.  Heart Island Conservation Area

Tiger swallowtail female at Sericocarpus. Females have extensive blue on the hindwing, lacking in males. Heart Island Conservation Area

While watching and waiting for this one butterfly, I found myself wondering about his spectacular color patterns, and what functions they might serve.  How had natural selection favored the evolution of such a delicate piece of living jewelry?

Great purple hairstreak at Sericocarpus

Great purple hairstreak at Sericocarpus

Brilliant colors and striking contrast are two of the components of pattern in both butterflies and birds that attract so much attention and admiration from naturalists, yet it struck me that we understand relatively little about how these patterns are actually adaptive, beyond a few simple generalizations.

Hairstreaks, for example, are usually instantly recognizable by the adornments of the hindwings.  Most have a pair of thin tendrils extending from the back of the hindwing, and the hindwing is often marked on the underside with spots of color that look something like eyes.  When perched, most hairstreaks habitually rub their hindwings back and forth across each other slowly, while movements by the rest of the insect are slight and barely noticeable.  The adaptive function of the tendrils, spots and movement seem to be to mimic a head and antennae, which presumably misleads potential predators into directing their attack to the hindwings.  It’s not uncommon to see hairstreaks with symmetrical chunks removed from both hindwings, indicating that a predator wannabe fell for the ruse and got nothing but a mouth or beak full of chitin and scales.  The hairstreak survives the attack only a little the worse for the encounter.

This gray hairstreak shows apparent predator damage to the rear of its hindwings.

This gray hairstreak shows apparent predator damage to the rear of its hindwings, suggesting that the tendrils and eyespots there enticed the predator away from the head.

So I get that part.  But what about the other pattern components that are so conspicuous, such as the patches of lime-green scales on the hindwings, and the brightly bicolored orange-blue abdomen?   As much as I love all things Gator-related, that seems unlikely, although there are also some very cryptic grasshoppers that have brilliant contrasting orange and blue patches on the inside of their hindlegs, visible only briefly and sporadically, that must have some kind of signaling function.  Why orange and blue?

Great purple hairstreak. Heart Island Conservation Area

Great purple hairstreak. Heart Island Conservation Area

And then there’s the southern aspect of a great purple hairstreak traveling north.  Not only do they have the wispy tendrils and eyespots on the hindwings – they also have flanges extending from the rear margin of the wings that produce a remarkably face-like visage as the butterfly is walking away.  What is that supposed to look like?  I’m hard-pressed to ascribe a resemblance to any insect I can think of, but it seems likely to me that this is also a feature favored by natural selection somehow, perhaps because of some protective function.

Great purple hairstreak from behind.  Heart Island Conservation Area

Great purple hairstreak from behind.  What kind of face do you see?  Heart Island Conservation Area

The swallowtails represent an entirely different suite of characteristics, but are similar in some respects to the hairstreaks.  Big, conspicuous, almost constantly in motion, brightly colored – the overall effect of the swallowtail motif can’t be concealment.   A couple of the tiger stripes, however, converge towards the abdomen, and in many swallowtails there are conspicuously colored spots just below the convergence of these stripes that could function as eyespot mimics.   The tails of swallowtails may serve a similar function to the tendrils of hairstreaks, attracting the attention of predators towards these disposable and dispensable wing pieces.

Male tiger swallowtail at Sericocarpus.  Heart Island Conservation Area

Male tiger swallowtail at Sericocarpus. Heart Island Conservation Area

One big difficulty in interpreting color patterns and their functional significance lies in the realization that human observers often aren’t even seeing the color patterns other butterflies, or their predators such as birds, might be seeing.  Many insects and some birds can see well into the ultraviolet range of the color spectrum, invisible to humans.    Butterfly wings (and flowers as well) reflect heavily in the UV, so what appears to be a single color without any obvious pattern to us is richly patterned to a potential predator, conspecific, or nectarivore.

Viceroy at Sericocarpus.  Heart Island Conservation Area

Viceroy at Sericocarpus. Heart Island Conservation Area

Even in species where we think we have a clear understanding of the significance and evolutionary logic behind butterfly color patterns, the full story is sometimes more complex than initially imagined.  Take Viceroys, which traditionally have been considered to be a classic (Batesian) mimic of the unrelated monarch butterfly.  Any decent naturalist can tell a monarch from a viceroy pretty easily; not only are there differences in specifics of the color pattern (especially a transverse black band on the upper hindwing of viceroys, lacking in monarchs), but also major differences in flight patterns.  Still, as the old story goes, viceroys gain protection from predators because of their similarity to monarchs (and other danaids like queen butterflies).    Monarchs are avoided by many predators because they feed on and store (sequester) toxic compounds from their larval hostplants, which include various species of milkweeds (Asclepias spp) and relatives (such as Sarcostemma).   These compounds, called cardenolides, cause fairly immediate digestive upset in naïve predators that try to eat one, and they quickly learn to avoid any similar appearing butterflies in future feeding attempts.  Monarchs have evolved a bright and conspicuous orange and black color pattern to warn potential predators of their toxicity. This pattern of warning coloration is known as aposematic coloration.

Monarch (Danaus plexippus).  In the traditional explanation, the monarch is the model (unpalatable species) for the viceroy (palatable species) in a Batesian mimicry system

Monarch (Danaus plexippus). In the traditional explanation, the monarch is the model (unpalatable species) for the viceroy (palatable species) in a Batesian mimicry system

Viceroys, the willow feeders, were long considered to be perfectly edible, palatable insects that gained some protection by their resemblance to the emesis-producing monarchs.  In a series of clever experiments, lepidopterist and evolutionary biologist David Ritland showed back in the 90’s that in some areas like south Florida, viceroys are actually more distasteful and unpalatable to bird predators than co-occurring populations of monarchs or closely related queens.  The monarch and queen larvae in these areas feed mostly on species of milkweed (Asclepias tuberosa, Sarcostemma clausum) that have very low concentrations of cardenolides, leaving the danaid butterflies (monarchs and their relatives) relatively palatable.  The viceroys, by contrast, sequester toxic phenolic glycosides from their willow hostplants.  When abdomens of viceroys and queens were offered to predatory birds (red-winged blackbirds) in the lab, the birds rejected the viceroys more often than they did the queens.  So in some areas, viceroys are apparently the more distasteful model (or co-model, in a form of shared aposematism called Mullerian mimicry) and monarchs and queens the more palatable mimics.

Viceroy with wing damage suggestive of a predator attack.  Notice the symmetrical chunks missing from both hind wings, and the V-shaped pieces missing from the left wings.  Most likely, a predator (bird, lizard?) grabbed the wings while this butterfly had them folded.

Viceroy with wing damage suggestive of a predator attack. Notice the symmetrical chunks missing from both hind wings, and the V-shaped pieces missing from the left wings. Most likely, a predator (bird, lizard?) grabbed the wings while this butterfly had them folded.

So maybe in science, as in life, a little humility is a good thing.  It’s often the case that we don’t understand complex natural systems as well as we think we do on first consideration.

Reconnoitering the rim

September 14, 2013

Taking photographs is one of my main reasons for going into the field.  The most important reason is, of course, to see fascinating flora and fauna, and perhaps learn a bit about how they make their way through the world.  But capturing images of at least some of the plants and animals runs a close second.  Those images are almost entirely for my own purposes; only a very small fraction are ever seen by anyone other than me.  So maybe it’s not a big deal that the most stunning image I’ve experienced in some time is one that I will never be able to share.   Driving north on SR19 through Ocala National Forest on Saturday morning, about 15 minutes before sunrise and a mile or so north of Silver Glen Springs, I saw an animal crossing the road a couple hundred yards ahead of me.  No other traffic in sight.  The telltale trot told me immediately it was a coyote.   I don’t see coyotes often, and truth be told, I don’t get that excited about mammals in general.  Stinky nocturnals, for the most part.  But I adore dogs of every size, shape and temperament.  Seeing a wild dog is for me a pinnacle experience.

It was during that transitional period between dawn and the full light of sunrise, when colors are beginning to become apparent, but still somewhat muted.  I was on the coyote in no time, and she maintained her steady lope across the road and onto the shoulder, about a fifteen foot wide swath of mowed grass, ending where the dense ground cover and low vegetation of oaky scrub began.  As I passed her, now slowed down to maybe 30-40 mph, she stopped at the edge of the shoulder, turned broadside to me, and watched me as I drove past.  I locked eyes with her.  Then she turned and was gone.  I don’t know exactly what happened to my neurochemistry at that moment, but I’m pretty sure it involved a massive flood of several happy neurotransmitters.  Dopamine, adrenaline, oxytocin – who knows?   As I drove away from that brief but intense moment, I felt changed, and elated in a way I don’t often experience.  Privileged.   That image, that moment of looking into the eyes of “God’s dog”, will be forever burned in my brain.  I couldn’t  help but wonder later what was going on in the coyote’s agile mind.   For me, it was a feeling of intense awe and admiration.   For her, I can only guess.   Curiosity, for sure, probably a bit of fear, and if coyotes have anything like a collective unconscious or shared genetic memory, perhaps a big dose of disgust and mistrust over the way humans have for centuries abused and tortured these beautiful little canids.   Hard to imagine a better start to the morning, even if I have no photograph to document the moment.

Ocklawaha Lake from the Kirkpatrick Dam

Ocklawaha Lake from the Kirkpatrick Dam

Ocklawaha Lake, aka Rodman Reservoir, was my first destination, and from there I planned to explore some new roads along the northeast rim of the forest.  Several weeks ago I discovered serendipitously that one of my favorite roads through the forest, FR11, continues over the Kirkpatrick dam that forms Ocklawaha Lake.  The dam was built as part of the abandoned effort to build the Cross-Florida Barge Canal across the peninsula in the ‘60s, and it remains controversial, pitting environmentalists who would like to see the dam removed to restore the Ocklawaha River to a free-flowing state against sportsmen who wish to protect the outdoor recreation opportunities it provides.  I just wanted to see migrant birds.  I was hoping that some of the floodplain forest in the area would be teeming with brightly-colored warblers and other neotropicals.   A couple dozen or so herons and egrets (great blues, little blues, snowies, great egrets and a single green) and dozens of vultures, who seemed to regularly roost on the dam and along the road that crosses it, were the only birds I could turn up there.

Snowy egret and great blue heron. Ocklawaha Lake

Snowy egret and great blue heron. Ocklawaha Lake

Dubbed "Sand Land" by some creative soul on Panoramio, this scrub barren on FR 11 just south of Ocklawaha Lake is the result of off-road vehicle abuse of the scrub habitat.  Even though vehicular use of this tract is no longer permitted, it remains in this degraded state.

Dubbed “Sand Land” by some creative soul on Panoramio, this scrub barren on FR 11 just south of Ocklawaha Lake is the result of off-road vehicle abuse of the scrub habitat. Even though vehicular use of this tract is no longer permitted, it remains in this degraded state.

Forest Road 74 crosses Forest Road 11 just south of Ocklawaha Lake.  I drove west on FR74 into unexplored territory.   A mobbing response by a small flock of passerines included several towhees in various states of moult and dishevelment, a couple of prairie warblers, and some residents like Carolina wrens and cardinals.  A bit further down the road, a second mobbing flock was more diverse, and contained several northern parulas, a yellow-throated warbler or two, scrub and blue jays, and a distant Empidonax flycatcher I didn’t come close to photographing.  I was pretty pleased with myself just to be able to ID it as an Empidonax; identifying it to species, without vocalization, is outside of my skill set.

Male eastern towhee, still looking sub-prime from his post-nuptial molt.

Male eastern towhee, still looking sub-prime from his post-nuptial molt.

Female northern parula

Female northern parula

Leaving that flock, I spotted a medium-sized snake stretched out in the bare sand of the scrub alongside the road.  Black racer.  Surprisingly, he let me drive to within 10’ or so without bolting.  As I moved slowly to get the camera into position, I was holding my breath that I wouldn’t spook the racer before I got off at least a few shots in this delicate, diffuse morning light.  Black racers are pretty easy to find, but not easy to photograph for me.  These are intensely visual snakes, and I suspect in my entire experience with the species, I’ve only seen them a few times before they have seen me.   A much more common experience is to spot one while glassing the habitat for whatever, only to realize the snake already has a visual lock on me.   From distances up to 30-40’ away.   These snakes don’t miss much.  On the occasions when I’m fortunate enough to watch one hunting my backyard and gardens, I’m always struck by their awareness of their environment, periscoping frequently to elevate their head above the ground cover and assess their surroundings.  Typically, any quick movement on my part precipitates a rapid retreat to cover by the snake.   Which is exactly what this racer did the first time I tried to inch a bit closer for a better shot.

Black racer basking

Black racer basking

Black racer

Black racer

Black racer periscoping.  From my yard, hence the noxious St. Augustine grass

Black racer periscoping. From my yard, hence the noxious St. Augustine grass

FR 74 leaves the forest a couple of miles west of FR 11 and passes through private land; I took FR09 south to get back into the sparsely traveled roads of the national forest.  Another fine mobbing flock in an ecotone between oaky scrub and sand pine scrub was the best of the morning – perhaps 15-20 birds, including scrub jays, towhees, prairie warblers and northern parulas, a white-eyed vireo, tufted titmice, cardinals, a woodpecker or two, Carolina wrens.  The usual suspects.   And ovenbirds.  Once again this weekend, they were chewking from dense cover in nearly every mobbing flock I encountered.

Florida scrub jays

Florida scrub jays

Prairie warbler

Prairie warbler

Immature female eastern towhee molting into her first adult (basic) plumage

Immature female eastern towhee molting into her first adult (basic) plumage

Ovenbird

Ovenbird

FR 09 in this area is notable for another reason – topography.  Not much by most standards, but enough to allow extended views of the surrounding habitat mosaic.  The presence of actual hills and draws in the forest is always a welcome surprise.

Topography (of sorts) on Forest Road 09

Topography (of sorts) on Forest Road 09

From FR 09, I took FR70 back to the east.   Soon after passing into one of the large tracts of clearcut sand pine scrub, I saw a large, dark raptor flying low across the landscape and swoop up into the top of a lone sand pine that had been left standing.  Profile and flight pattern didn’t look like the raptors I see most often, but as soon as it perched I could see the ear tufts.   A great horned owl, hunting (?) in broad daylight, on a sunny morning, around 10:00 a.m.   That’s something I don’t see often.  Until earlier this year, I’ve always thought of great horned owls as a “bird of the day” species.  Typically I see them only a few times a year.   Since June, I’ve seen great horned owls at least 10 times in a half-dozen or more different locations.  The serendipity of birding.   

Great horned owl, hunting at mid-morning.

Great horned owl, hunting at mid-morning.

Great horned owl youngster, from earlier this year at Lake George Conservation Area

Great horned owl youngster, from earlier this year at Lake George Conservation Area

Some time around 1100, I made it back to familiar ground; FR 70 intersects FR11 just north of the Riverside Island tract where I have had such good luck finding red-cockaded woodpeckers this year.  None today – it was far too late in the morning and too warm for much bird activity, though I did find a pair of American kestrels hunting in the same open sandhills tract where I have seen them before.  Almost certainly a breeding pair; I haven’t seen any migrant kestrels yet this year at the spots where I usually find them.

Forest Road 70 where it passes through an isolated live oak hammock amidst the sandhills

Forest Road 70 where it passes through an isolated live oak hammock amidst the sandhills

While driving south on FR11 through majestic mature sandhills, I was watching some mixed roadside clumps of goldenrod and evening primrose for pollinator activity and noticed the reticulate wings of some rather large insect in the foliage of one of the primroses.   It was one of the larger species of antlions (Myrmeleon sp?) that had been snagged by a nearly invisible green lynx spider (Peucetia viridens) only moments before.  It was still oozing hemolymph from the spider’s puncture wounds, and it seemed to still have a glimmer of life in its many eyes.   Green lynx spiders – what fierce predators those lovely arachnids are.  There don’t seem to be any size limits or taxonomic boundaries on the prey these oxyopid spiders will tackle.  Tough luck for the antlions and myriad other prey taxa.

Green lynx spider (Peucetia viridens) with antlion prey

Green lynx spider (Peucetia viridens) with antlion prey

From a coyote to a lynx – a good morning for the predators, and me.  If I continue exploring new forest roads at my current pace, I should have thoroughly traversed the forest by the time I’m ready to retire.   Ocala National Forest – the gift that keeps on giving.

Plant it and they will come

August 18, 2013

A Polydamas or gold-rim swallowtail that has just emerged from its chrysalis.

A Polydamas or gold-rim swallowtail that has just emerged from its chrysalis.

This is a Polydamas swallowtail, Battus polydamas, one of the tailless swallowtails.  Up until a few years ago I had only seen them on a couple of occasions, and then only briefly.  Now I see them every summer for months on end; sometimes there are a half-dozen or more flying around my yard.  The reason for this quantum leap in the frequency with which I see them is easy to explain – I planted their larval foodplant in my garden.

This freshly emerged adult had a purple powder on his head and thorax.  No idea what that is.

This freshly emerged adult had a purple powder on his head and thorax. No idea what that is.

By itself, that’s not surprising at all.  One of the prime directives of butterfly gardening is to plant a variety of plants that are hosts to the caterpillars of the butterflies you’d like to attract.  It works.  What is suprising to me, though, is that these Polydamas swallowtails,  which by my reckoning are pretty uncommon, so rapidly find new patches of larval host plant and exploit them.

Pelican flower, Aristolochia grandiflora, blooming with Senna bicapsularis, Christmas Senna.

Pelican flower, Aristolochia grandiflora, blooming with Senna bicapsularis, Christmas Senna

I bought the house I currently live in a little over 5 years ago, and like most new houses in typical subdivisions, the landscaping was pretty bland, generic and mostly non-native.  So I began planting for wildlife, concentrating on plants that provide nectar for insects or hummingbirds, fruits for birds, and caterpillar food for a selected set of lepidopterans.  One of those plants was Aristolochia grandiflora, or pelican flower, an aggressive vine native to the Caribbean and Central America.  Polydamas swallowtails, as well as their close relative the pipevine swallowtail (Battus philenor), are highly specialized feeders as larvae, feeding only on pipevines in the genus Aristolochia.  I’ve never seen any of the 7 native species of Aristolochia that occur in Florida.   Of the two native Battus species, I see pipevine swallowtails far more often than Polydamas, but still don’t consider them common.

Polydamas swallowtail eggs. They seem to normally lay them in small clusters.

Polydamas swallowtail eggs. They seem to normally lay them in small clusters.

Within a few months after the pelican flower vine I planted started growing vigorously in its second year, the Polydamas swallowtails found it, colonized my yard, and have been a continuous presence every summer since.  Sometimes there are so many caterpillars they almost entirely defoliate my single vine, which covers most of a 4 x 6’ trellis.   One of the  advantages of rarity in a plant is that it makes it unlikely that specialized herbivores will find and consume it.  Escape in space and time is what ecologists sometimes call that strategy.   Polydamas swallowtails seem to have countered that rarity strategy pretty effectively with their incredible ability to find and exploit these widely scattered plants.

The question that remains unanswered for me is, how do they do it?

Mating pair

Mating pair

Female laying eggs on pipevine

Female laying eggs on pipevine

Young Battus caterpillars that have just shed their first-instar exoskeleton.

Young Battus caterpillars that have just shed their first-instar exoskeleton.

Early instar Polydamas caterpillars.  They are gregarious when small, but become more solitary in later instars.

Early instar Polydamas caterpillars. They are gregarious when small, but become more solitary in later instars.

Middle-instar caterpillars

Middle-instar caterpillars

Late-instar Battus caterpillar

Late-instar Battus caterpillar

Late-instar larva of Battus polydamas everting the osmeterium

Late-instar larva of Battus polydamas everting the osmeterium

Chrysalis

Chrysalis 

Eclosing adult.

Eclosing adult.

Whatever the answer, I’m glad they do. The caterpillars are big honkers when approaching pupation, sometimes boldly tiger-striped. As is typical of swallowtail caterpillars, they have a pair of fleshy horn-like protuberances (the osmeterium) that they can evert from their head when alarmed. They exude a not-unpleasant, to me, odor that may repel some potential predators. It’s also been suggested it looks like the forked tongue of a snake, which may afford the caterpillars some protection through a form of mimicry. So the caterpillars are cool to have around. Then there are the adult butterflies. What an entertaining lep to watch these guys are; they are like rockets, zipping from foodplant to nectar source at what seems to me to be among the fastest flight speeds seen in swallowtails. They never stop – even when nectaring, they are constantly hovering, just barely supporting their weight with extended legs. When not feeding, the males are like jet pilots engaged in dogfights with their high-speed chases, stoops, and climbs. They also frequently chase other butterflies, and sometimes even small birds that dare to cross their airspace. Bad ass.

Polydamas swallowtail nectaring at Salvia coccinea

Polydamas swallowtail nectaring at Salvia coccinea

The closely related pipevine swallowtail, Battus philenor.  I've had them in my gardens a few time, but not as frequently as the Polydamas.

The closely related pipevine swallowtail, Battus philenor. I’ve had them in my gardens a few time, but not as frequently as the Polydamas.