Royal Conundrum - Killing the Monarch Butterfly with "Kindness"

The monarch butterfly population has been in serious decline for years now, something many gardeners know. To compensate for habitat loss, gardeners have been encouraged to plant more milkweeds, the insect's larval host plant. But this has led to unforeseen negative consequences, especially in warm winter regions of the U.S.

Native milkweeds can be hard-to-impossible to find, so the tropical, showy "scarlet" milkweed has become ubiquitous in garden centers across the country. This plant, Asclepias curassavica, is native to the American tropics and has spread to pantropical regions worldwide. It has become invasive in some areas, and threatens to become a pest in South Florida. 

Many monarch butterflies harbor a protozoan, Ophryocystis elektroscirrha (OE), that can weaken the adult, prevent the pupa from emerging from the chrysalis, or deform the wings. Monarchs visiting milkweeds deposit spores when they visit milkweeds. Normally, migration culls weakened individuals, and the OE spores die when the plants die back in winter. The plants grow back in spring and summer with fresh, uninfected leaves. But in areas with warm winters tropical milkweed grows all year, thus maintaining high levels of OE spores. Areas of Georgia, coastal Carolinas, Florida and the Gulf Coast have become hotspots of infection.

Monarch on Scarlet Milkweed

Apart from the immediate threat to individual monarchs, year-round milkweed is also, probably more ominously, threatening the migration itself. The presence of the milkweed affects the butterfly's hormonal balance, and works as a trigger to make it reproduce. So monarchs that find themselves in areas with warm winters don't migrate, and a year-round population gets established. With increasing warming trends this area of permanent, sickly individuals will only increase. 

Migration plays a critical role in maintaining a robust gene pool, for it culls badly infected individuals, which simply don't survive the trip. But migration may play other vital roles as well, in ways  we haven't discovered. 

Some organizations like the Xerces Society and the Florida Native Plant Society actively campaign against the use of tropical milkweeds. Some people, though, citing the drastic declines in the monarch population, feel that keeping the numbers up is of primary importance. 

Weaning gardeners away from tropical milkweed is going to be a monumental project, especially since it was promoted so aggressively as a solution to monarch population decline. 

Monarch on Asclepias curassavica

In and of itself, I'm not particularly heartbroken over the loss of scarlet milkweed in our yard. Due to neglect, they've sort of died out this spring anyway. It is a water hog, and the stems quickly get leggy and woody. It also is a magnet for aphids and spider mites, which would make any self-respecting female monarch look for greener pastures. 

Aphid-Infested Milkweed

Finding natives or even native seeds, is going to be a long, drawn out process. Some mail order nurseries offer native milkweed species that theoretically would grow here, but I'd have a better chance with offspring originating  much closer to home. 

Even though they might be the same species, a plant grown in the mid-Atlantic or Midwest would be quite different genetically from one that has adapted to South Florida conditions. They might not even look the same, they might not  survive, and they certainly wouldn't do anything to maintain genetic diversity. Ecologically even North Florida differs greatly from the southern part of the state.

Asclepias incarnata, "Swamp Milkweed," a Native

But there's a further complication!

Whether it comes to weather patterns, the density of bear fur, and many other things, matters often are much more complicated when it comes to the southern peninsula of Florida. It seems that there is an established, non-migratory monarch population south of Lake Okeechobee.  The most-studied migration routes don't cover us, especially on the sw coast, though we might get a few strays. I have had basically year-round monarchs since I began butterfly gardening around 1995. Over the years I have seen newly-emerged monarchs with deformed wings, but not a lot. Even without the scarlet milkweed, all of our native milkweeds might not go completely dormant during our winters, so a small population could persist theoretically without our help. The assumption has to be that the infection rate in our monarch population is close to 100%. 

So, in a way, it doesn't matter whether we keep planting Asclepias curassavica, but it goes against the grain now that I'm aware of a problem. While I don't like the plant, and getting rid of it would not stop the problem of diseased butterflies, it still seems somehow that replacing it with its cousins that "belong here" would be ethically as well as esthetically better. Now comes the hard part - actually doing it. 

Once You Have Goldenrod . . .

 "Once you have goldenrod, you will always have goldenrod," was the cryptic remark of a stalwart in the Naples chapter of the  Florida Native Plant Society when I took home a specimen she had potted. I asked what she meant, and she just gave me a wry smile, and said, "You'll see."

It didn't take too long. Look up "goldenrod" on a search engine and you'll find topics like, " How do I control goldenrod in my garden," and "How do I get rid of goldenrod in my garden."

Besides being tough as nails, the species I got from Freda spreads vigorously by rhizomes. Pot it up, and it creeps out through every drainage hole. Pull it out, and it shows up across the path, or in a neighboring bed after a few weeks. It produces thousands of seeds, but they don't seem to be all that viable, because the plant doesn't jump all the way across the yard, but stays mainly in the general area where I first planted it. Maybe the seeds are mostly for the little creatures that must eat them.  

"Our" goldenrod grows outside the easterly wall, which is remarkably deficient in windows, so I don't have a good idea of what goes on with it. Still, I get the idea that the butterflies and skippers that visit us generally find other flowers in the yard more attractive. On the other hand, I rarely pass by it without seeing some manner of wasp or bee vigorously stuffing itself or collecting pollen. Often there may be several species feeding at the same time.

Paper Wasp on Goldenrod

The plant in our yard seems to fit the description of Solidago fistulosa, "Pinebarren Goldenrod," better than any others, but I'm making no guarantees. There are over 100 species of goldenrod worldwide, and they hybridize readily. On the other hand, according to the 1998 edition of Wunderlin's Guide to the Vascular Plants of Florida, only about 5 species occur naturally in southern Florida, and it doesn't really look like any of the other possibilities.

Goldenrod, Pen & Ink

It doesn't form a classic basal rosette like many members of the Aster Family, including some goldenrods, but just pops straight out of the ground, and reaches for the sky, unburdened by any side branches. Narrow, lance-shaped leaves, sometimes with toothed margins, alternate around a bristly stem. The leaves are attached directly to the stem, with no petioles. As the stem elongates, the lower leaves wither and may or may not fall off.

The inflorescence is somewhat pyramidal, and made up of graceful, arching wands, alternating around the stems, and bearing numerous saturated yellow heads. The heads have both disc and ray florets, but the latter are a little sparse. The stem usually forms just one inflorescence, at its end, but if you cut off a faded inflorescence, the remaining stem sometimes will produce more blooming wands on its sides. It won't make a new, blooming "pyramid." 

Goldenrod Sketch

The stems can get up to 6 feet tall (though mine don't get that high), and the leaves die from the bottom up, so eventually you have a cluster of dead heads and seeds atop a bare stalk irregularly flagged with withered leaves. That's definitely when it needs to be cut back hard, but being a negligent sort of gardener, I rarely do that in a timely manner. This trait could be masked a bit if the goldenrod were placed behind lower-growing plants. Some of ours have spread into a clump of lavender lantana, but it stays too low to hide the stems completely when they get unsightly. 

It's often windy here, and I should stake them. If our yard were bigger, and the  garden beds wider I could let the goldenrods droop,  but as it is, they flop over and obstruct the path, and become something of a nuisance. It's a magnificent plant, and I wish I had space for a grand swathe of it, bending and bowing in the breeze, instead of my constrained, small patch. But I wouldn't do without it. For one thing, it reminds me of the wisdom,humor, and lop-sided smile of a long-dead friend. 

Megachile Bee on Goldenrod

 

Signs of Spring

Just a few days ago I heard the familiar lament, "I like Florida, but I really miss the change of seasons." We don't have jonquils and crocus, but  there are plenty of signs heralding the advent of spring in SW Florida. As for color signals, what more do you need than the show put on by flowering trees - deep yellow Tabebuia,cooling lavender Jacaranda, delicate pink masses of flowering almond - just to name a few.  

The trees named above aren't native to Florida, but so much goes on in March in the natural world that I labeled 2 posts "March Madness" in 2017. This year has been a little crazy apart from the garden, and  I have made many more scribbled notes than sketches. I hope to catch up on some of the later spring manifestations.

The return of the swallow-tailed kites is a sure sign that the winter has turned. I spotted my first one of this year in the second week of March. These striking white-and- black-marked raptors demonstrate how little color has to do with real beauty. No matter how many I've seen, a soaring swallow-tailed kite still takes my breath away. Author and artist David Allen Sibley talks of their,"unmistakeable; incredibly graceful, flowing flight."(The Sibley Guide to Birds, p. 111). The birds don't use just their tail feathers for maneuvering, but also can twist their entire lower body to execute their aerial acrobatics.

Swallow-tailed kites nest in tall trees in hardwood forests, and due to development, especially intense timbering and replacement of mixed forests with pine plantations, their range in the U.S. has shrunk drastically. They used to nest as far north as Minnesota. Now they are limited to peninsular Florida, and the coasts of Georgia, South Carolina, Alabama, Mississippi, and eastern Louisiana. They return to South America in the fall. 

They pluck their prey - reptiles, amphibians, insects and small birds from the treetops or catch and eat them in flight. I haven't read that they do so, but I wouldn't be surprised to find that they also rob nests of other species. Perhaps that is calumny, but "Mother Nature" isn't kind, and she doesn't always go by the rules.

Frangipani, Plumeria sp., isn't native to Florida, but it consumes few, if any, resources, and isn't invasive. It is a quintessential "pass-along" plant. I got mine from a sister, who got hers from a friend. All you have to do to grow it is stick a branch into the dirt, water a little, and watch it grow. Once it is established it needs no irrigation or fertilizer. (At least the one in our yard behaves that way). There are many species and varieties, but the only two I see around the neighborhood are a  pink-flowered and a yellow-flowered one. Ours is  yellow-flowered, and fragrant. Frangipani is one of the flowers traditionally used in Hawaiin leis.

Frangipani Flower Cluster

Once the weather is good and dry, frangipanis lose all their leaves, and look completely dead and more than slightly creepy - like some sort of alien life form, which is just waiting to emerge and wreak havoc. 

Dormant Frangipani Branch

I used a variety of colored pencils to capture the gray-green, turgid look of these branchlets, which really do resemble dead fingers. The true color is something in between all my attempts. The large dry markings are leaf scars from previous seasons, and the squiggly maroonish things at the very tip are nascent leaves. New growth literally bursts through the skin. Buds and stems don't magically appear on the branches, but rupture the skin, leaving oozing wounds. 

Last month, bloom stalks capped with numerous flower buds started rising from the branch tips, and now the first flowers have opened. The plant is a member of the Dogbane Family, and all parts, including the white sap, are somewhat poisonous. I haven't found the sap irritating, but I haven't gotten much on my skin, and other people might have a reaction to it.

Emerging Flower Stalk
Maroon Structures are Young Leaves

The Great Southern White and Florida White butterflies reappear in mid-to-late March. Both occur here about the same time, and I'm not quick enough to id them on the fly. When we first moved here in 1994, we would see great swarms of white butterflies, but now we see them singly or maybe in pairs. If you can get close enough to see them, the bright turquoise tips on the antennae are a dead giveaway for the Great Southern White.

White Butterflies:
Great Southern White, Left, and Florida White, Right

The emergence of lubber grasshopper nymphs is also a marker for spring. The nymphs start emerging in great numbers in February. So far they have defoliated one bougainvillea, and demolished the Crinums and Tradescantias. They'll all recover, with the possible exception of the Tradescantia. which really are happier in more northern sections of Florida. There must be many microorganisms that afflict the nymphs, because the number of adults I see later on is a fraction of the immature population. Both nymphs and adults allegedly are toxic to most predators. 

Newly-Emerged Lubber Nymphs

Just like "up north," perennials are forming new basal rosettes and resuming growth. Elephant's foot and rosinweed have made a fine beginning, while blackroot and Pluchea have resprouted directly.  Native grasses like Elliott's Love Grass and Pink Muhley are sending out fresh, colored blades from what clumps of dried foliage from last year. Gaillardias sown by last year's plants are germinating here and there in the yard. I leave them where they don't block a path, and try to transplant others, even though it sets them back. 

March brings persistent drying winds. Our last rain was the second week in February, and given the wind and increasing sunshine I have to water at least twice a week now, whereas during winter even the potted plants don't require a lot of attention. 

Blue-Eyed Grass

Blue-eyed grass made a magnificent display throughout late winter and early spring, but is going to seed now. The tickseed is also beginning to appear somewhat the worse for wear.

It's March Madness in the garden all over again. There is plenty more going on, but I have to stop for now.

Corkystem Passionvine

 Corkystem passionflower (Passiflora suberosa L.) is a mainstay of my butterfly garden. I just wish it would grow where I want it instead of collaborating with the birds to migrate to places where it is a pest. So far it has resisted my attempts to train it up a trellis or fence, yet it scrambles exuberantly in, around, through, and over shrubs and trees. If it has nowhere to climb, it spreads happily over the ground, especially where I have planted native heliotropium (Heliotropium polyphyllum). I could leave it as a ground cover, but since it is a vine, it presents a tripping hazard. I have a lot of digging out and potting up ahead, because I need to save at least some of the volunteers.

The genus Passiflora is the larval host for the zebra longwing, julia longwing, and much under-appreciated Gulf fritillary. The striking, orange Julias are uncommon in our garden. They tend to show up in a bunch and then disappear for years. We sometimes get zebra longwings, but they really prefer a shadier habitat than our yard offers. Zebra longwings roost in long chains at night, and the sight of such chains is absolutely breathtaking. The zebra longwing is Florida's state butterfly.

Gulf Fritillary Caterpillars on Passiflora suberosa

Zebra Longwing Caterpillar
Unripe Passiflora berries
Collier-Seminole State Park 

The beauty of a Gulf fritillary is hard to capture in paint or with my  very basic camera equipment. A newly-emerged adult gleams bright copper-orange, like the proberbial new penny. The undersides of the wings have a pattern of iridiscent silvery patches which reflect light spectacularly and brilliantly. 

The scanner cannot capture the silvery flash of the underwings.
These are dead individuals I have collected from the yard.

Passiflora suberosa is one of 7 species of passionflower native to Florida, but the purple passionflower, P. incarnata, is the only other one which occurs naturally in this area. Several exotic species, like the flamboyant scarlet passionflower ( P. coccinea) also flourish in the state. P. incarnata is a large vine, has a showy purple flower, and will get devoured by caterpillars. It dies back during our dry season.

"Maypop"  is another common name for P. incarnata. When I was a child we lived in South Carolina with my grandparents and unmarried aunt while my father served in the Korean War. I tagged along with my Aunt Iola, whom I called "Ant Ola." (I still pronounce "aunt" as "ant").

Even though I was afraid of the cows, who seemed awfully big, I liked accompanying my aunt when she took them out to pasture every morning. What I later realized was P. incarnata grew wildly in one spot. I asked her what they were, and she replied, "Maypops." When I asked her why, her answer was, "because they may pop and they may not." It is fascinating how certain little things can be preserved so vividly in our memories.

Zebra Longwing
Heliconius charitonius
Delnor-Wiggins Pass State Park

Corkystemmed passionflower is much more diminutive, and far less showy than its purple and red cousins. I agree with Rufino Osorio, who writes that while it first seems to have no obvious horticultural appeal, it's merits show themselves over time. The vine begins tender and green, and gradually adds ridges of corky material until it is enclosed completely.  Near the roots of an undisturbed vine the stem can reach a diameter of an inch or more, and certainly presents an interesting texture. 

Passiflora suberosa
Notice Corky Stem

The leaves have longish petioles and alternate around the stem. The surfaces are smooth, and the color varies from a yellowish green in bright sun to a more intense green in shade. The petioles have 2 raised "dots" opposite each other close to the base of the leaf. These are extrafloral nectaries. The plant  often displays "heterophylly," a fancy term for having leaves of different shapes. They can be simple and entire, or partially or deeply lobed. The presence of heterophylly in the plants in our yard varies, probably depending on what has been pollinated. Roger Hammer writes that lepidopterists surmise that the varying shape is a means to fool the butterflies so they don't lay as many eggs on the plant. The vine climbs and clings by tendrils emerging at the base of the leaves.

Heterophylly in Passiflora suberosa

The flower is small and delicate, about one-half to three-quarters inch in diameter. What look like petals, but really are sepals, are white or pale spring green. Pollinators of various sorts like them, because they produce a lot of berries throughout the year. The fruits start out green, turn blue, and then blue-black when ripe. Sometimes they have a chalky "bloom" like blueberries. They are roughly spherical and about a quarter-inch in diameter - about the size of a Spanish caper. They don't taste bad, but contain so many tiny seeds that they are mostly grit. Better leave them for the birds.

That brings us back to my struggle to keep the vine from eating the garden. The place it thrives most vigorously is all through and over a clump of bougainvilleas. The bougainvillea's vicious thorns and dense growth prevent me from getting at the passionvines' roots, and even if I did, the mockingbirds would reseed them promptly. They effectively cultivate the vine because they poop as they forage for the berries. The bougainvilleas aren't native, but they don't consume any resources beyond space and rainwater. The tiny white flowers nestled in the plant's hot-magenta-pink bracts attract a fair number of small pollinators, and the mess of bougainvillea branches and passiflora vines provides a prime nesting site for the mockingbirds. They have reared several successful broods there over the last few years. 

So it's a standoff. I can't beat it, so I settle for beating it back when it threatens, kudzu-like,  to suffocate the other plants. And I do like the butterflies.

Gulf Fritillary 
Agraulis vanillae
Nectaring on Blue Porterweed, Our Garden

 

Passiflora suberosa ranges from the Caribbean through Florida and the lower Rio Grande Valley, Mexico, and Central and South America. It has spread through much of the world, probably with the help of birds, and is considered an invasive exotic in serveral locales. It has a long history of use in folk medicine. It can withstand quite dry conditions if it has a little shade, but appreciates more water. It probably would not thrive in permanently soggy ground.

Sources:

Roger Hammer. Florida Keys Wildflowers. 2004. p. 127.

Rufino Osorio. A Gardener's Guide to Florida's Native Plants. 2001. pp. 290-91.

Richard Wunderlin. Guide to the Vascular Plants of Florida. 1998. pp. 443-444.

Simpson's Stopper

 Simpson's stopper, Myrcianthes fragrans, generally grows as a shrub or small tree up to 25 feet tall.  It is vary variable in form, and also can be pruned into any shape desired. It's formally pruned in many parking lot hedges, which is kind of too bad, since the constant whacking back vastly reduces flowering and fruiting. So even though many people in South Florida see it regularly, they don't notice it. On the other hand, the resulting dense growth produces a good nesting place for mockingbirds. 

 The Simpson's stopper in the front yard could be healthier, which is worrisome.  It's one of my very favorite plants, and it plays a vital ecological and esthetic role in our yard. Anchoring the front landscape design (such as it is), is not the least of its virtues. If it goes, it will leave a big hole. 

It started out as a multi-trunked containerized plant. I liked the outward spread of the trunks, so I left them. As it grew, I removed lower branches, partly because they were intruding on the path. The open, tiered canopy that developed is one of the plant's charms now. I just wish it were a bit fuller. "Limbing" it up also reveals the gorgeous bark, sometimes a perfectly smooth pale tan, as though it were sanded, and at other times turning reddish and peeling, a little like a crepe myrtle. The smooth bark phase is likely the source of one common name, "naked-wood."

Removing lower limbs also keeps the landscape more open and less-congested. It makes a nice screen between us and our neighbors to the left, but it isn't so dense that I can't see through it to their magnificent large Opuntias or the houses across the street.  No matter what your viewpoint is, you can see through and beyond the plant, so you are tempted to explore further. One of these days I am going to relocate one of my waterlilly pots so that birds can flit down for a drink or bath, and then retreat into the protective shade of the stopper.

The plant is evergreen, with opposite, mostly ovate leaves about 1 to 8 cm long,  and 1 to 4 cm wide. They are tough and leathery, with slightly underturned margins to reduce water loss. Depending on sun exposure, the leaves range from bright yellow-green to dark olive. The underside is a paler green. The leaves are covered with small glands, which appear as bumps on the upper side and as black or green dots on the underside.  I've never noticed any fragrance emanating from the leaves like it does from firs or spruces. Crushing the leaves, though, releases a fresh minty aroma something like eucalyptus oil. That's not surprising, since both are members of the Myrtle family, Myrtaceae.

In contrast with the leaves, the flowers really live up to their species epithet,  fragrans.  The plant blooms and fruits several times a year, depending on rainfall and temperature. When Simpson's stopper is in flower the air around it is filled with a spicy sweetness somewhere between the heavy, almost cloying odor of gardenias and the light, fleeting sweetness of citrus. When it is flowering I visit it several times a day, especially in late afternoon or early evening, just to breath deeply, as though I somehow could capture an olfactory  memory. Who needs mind-altering drugs when it is possible to wallow in pure sensation just by standing near a fragrant shrub and inhaling?

The all-white flowers grow in clusters on stalks that arise in the angle between leaf and stem. I think normally there are 5 tiny petals, though the one in my sketch above has 4. The numerous fine white stamens provide the main attraction, though. They practically obscure the petals, and a Simpson's stopper in full bloom looks like  the fairy godmother has waved her sparkle-trailing magic wand over it. The flowers are constantly humming with various pollinators, including beetles. Butterflies don't seem particularly fond of them, though. 

Flowers give way to rounded or somewhat pear-shaped fruits, often borne in pairs  - hence another common name, "twinberry stopper." They eventually reach a size somewhere between a blueberry and small olive, starting out green, then passing through yellow and orange stages before their final bright red. Mockingbirds gorge on the fruits, and if they happen to be frequenting the yard at the time, bluejays and cardinals also gobble the berries. The fruits are edible, somewhat sweet and not too dry, but for me leave an unpleasant bitter aftertaste. Volunteers pop up around the yard, evidence of the bird's activities. The plant also suckers, and probably could be propagated by severing them, too.

Apart from its other virtues, the Simpson's stopper functions as a kind of activity center in the yard. Even when they aren't feeding, birds like to perch on its branches. One July morning I made notes of what was going on around me while I sketched the fruits. I sat quietly enough that a mockingbird that had been flushed by my initial setup returned to the opposite side of the plant to continue eating. A shiny June beetle had its head stuck into a fruit, so intent on gorging that it let me manipulate foliage around it to make a photo. You can see a bit of my finger at the top of the photo.

Small bees and wasps buzzed amid the foliage and remaining flowers. Two other species of beetles were devouring fruits. Two strange insects that I couldn't ID were mating in the shrub's interior. A green darner dragonfly reconnoitered in search of prey or just patrolling its territory.  

I am wearing out the phrase, "superlative native plant," but that is because so many Florida native plants are, indeed, superlative. From its undemanding nature, repeated flowering and fruiting, glossy evergreen foliage, wildlife and landscaping value, Simpson's stopper certainly qualifies. It needs little water or fertilizer after it is established, and ours has survived major hurricanes Wilma and Irma with minimal damage. Though it gets pretty well defoliated by the salt-laden wind, it recovers quickly. 

It is named in honor of Charles Torrey Simpson (1846-1932), a noted South Florida plant explorer, snail expert, naturalist and nature writer. True stoppers are in the genus Eugenia, which also is in the Myrtle family. Simpson's stopper resembles them superficially, hence the most common common name.

Polydamas Swallotail

The Polydamas Swallowtail, Battus polydamas, is named after both historical and mythological figures from Greek history. Battus I founded the colony of Cyrenaica and its capital Cyrene on the coast of present-day Libya around 630 BC. Impressive ruins are all that is left. 

Polydamas figures in the Illiad as an advisor and friend of Hector. Polydamas of Skotoussa, who won the Olympiad in 408 BC, was an athlete of prodigious strength. Some of his feats appear on Greek pottery. The subspecies that occurs in Florida is Battus polydamas lucayous. I haven't been able to find a reference for "lucayous." 

The polydamas is the only swallowtail in the U.S. that doesn't have tails. This butterfly is sometimes called the gold-rimmed swallowtail as well for the row of yellow patches on the edges of its wings. Their larval food are pipevines, species of Aristolochia. In our yard they feed on the exotic Giant Aristolochia, and this year pretty well denuded the massive vine.

One year, when I didn't have any caterpillars I "imported" a batch from a friend about 25 miles north of me whose polydamas larvae were on the point of starvation after completely stripping  her Aristolochia plants.

 (The pipevine swallowtail, which also feeds on Aristolochia species, looks quite different. It has short tails, and it's deep black wings are brushed with bright blue iridescence. It has creamy patches near the margins on the upper wings, and large, bright orange patches on the undersides. It does not make it quite as far south as Collier County).

The polydamas is a strong, vigorous flyer, with a rapid, almost "nervous" wingbeat. I never have seen one basking. Even when nectaring, they keep up their fluttering, and I wonder whether they may actually feed on the wing like hummingbirds now and then. The ones in our yard fly about 5-10 feet off the ground when patrolling, swooping down mainly to lay eggs or take a sip of nectar.

Polydamas Checking Out Pipevine
Notice Yellow-Jacket Patrolling lower left

This is the best year for polydamas swallowtails in our yard for a long time. The last few years a few adults have showed up, some even laying eggs. But predators seemed to clean out the caterpillars, and repeat appearances by adults were rare.

This year I noticed the first polydamas in early May, and they pretty much stayed with us through mid- July. After about a week of no sightings, I see a brand new adult as we near the end of the month. Some of the adults who emerge probably stay here, but timing of appearance suggests that I also have had some visits by newcomers.

 I have seen polydamas swallowtails here as early as late February and as late as mid-November. They range up to north-central Florida, but may stray farther north. A subspecies occurs in coastal south Texas. Otherwise, they inhabit the Bahamas, Carribean Islands, southern coastal Mexico, Central America, and south to Argentina in South America. There are many sub-species.

Polydamas Swallowtail

The above quick and dirty, and not neurotically accurate color pencil drawings were made from a battered dead specimen I picked up years ago. I'm  not at all happy with the brown undersides. I tried layering different colors, but still did not pick up the elusive, reflective warm brown/black coloration.

The female lays a cluster of orange-yellow eggs on tendrils and tender young leaves. At first the caterpillars stay close together. There must be some evolutionary advantage in this behavior, but it also makes them very vulnerable to predators. A wasp can wipe out a brood in a matter of minutes. When they get about 3/8 to 1/2 inches long they go their separate ways.

Ovipositing Female

Young caterpillars are orangish tan to brown, with many bristles. The older caterpillar looks like a fat brown slug with orange tubercules protruding from its body. The larvae absorb toxins from the aristolochia, so they are distasteful to birds and lizards. But nothing saves them from hornets.

Too many times, I have watched a yellow-jacket methodically hunting the larvae amid the leaves and devouring them one after the other. All that is left is a little puddle. I'm lucky if even one or two individuals in some broods make it to adulthood. I  have had 3 sets of egg-laying so far this years, and apart from the first brood, the yellow-jacket has been there every day looking for prey. I'm hoping it  missed one here and there, but a successful brood may depend on timing with the emergence of adult  wasps. I just don't know. The interrelationships in the natural world are so complex. And we may be getting a distorted view of it on our tiny 60x110-foot plot.

The caterpillars are sort of dumb, even for creatures that low on the intellectual ladder. I've seen more than one start eating the stem between it and the plant, and then plop down to the ground once it has severed the connection. It doesn't seem fatal, though.

Polydamas Caterpillar

One year I got fed up with the yellow-jacket's gluttony and brought several caterpillars onto the screened patio. I cut new Aristolochia leaves and stems for them faithfully, but something went terribly wrong. None were able to form a complete chrysalis, and one never got beyond the J-stage. I don't know whether I deprived my larvae of some vital nutrient by feeding them cuttings, or whether they contracted some kind of disease. Now, even though the predation distresses me, I just leave nature to take its course. Besides, the yellow-jacket feeds its larvae with liquified caterpillars, and there's a place for them, too.

Butterflies usually leave the host plant to pupate, but I have found a lot of chrysalides tucked in along the vine. They resemble twisted leaves, dead or alive - some are green and some are brown with orange markings. They are very "architectural," and remind me of miniature sets of armor. The brown chrysalis in the sketch below has been parasitized. The spot that looks like an eye is the hole from which the parasite emerged. The chrysalis may hang vertically or horizontally.

Polydamas adults are particularly fond of the weedy Madagascar Periwinkle(Catharanthus roseus) that has been in south Florida most likely for centuries. It flowers at the end of the stems, and doesn't start blooming before it is pretty tall. The stems quickly get 3 feet tall or more, and it takes no time at all for them to lose a lot of leaves along the way, and look leggy, scraggly and bare. That's when I cut them all the way back. By the way they show up in the yard, they produce plenty of viable seeds. I also have a pinkish-magenta form, which the polydamas likes too. The center of the white ones usually is dark rose-magenta, but also can be green-yellow. The center of the pink ones is a dark rose.

A member of the dogbane family, Apocnyaceae, Madagascar periwinkle is quite poisonous. It is a prime exhibit for the argument of preserving plants, for potent anti-cancer drugs have been developed from its sap. While it is a ubiquitous escape in Florida, it hasn't been classified as invasive. I hope it doesn't reach that status because many kinds of butterflies love it, and it provides clumps of cheerful, clear whites and pinks all through the year. It actually is endangered in Madagascar, its place of origin.

White Madagascar Periwinkles

When I was taking high school biology I laughed at the naivety - even stupidity - of the early theory of "spontaneous generation" to explain how animals originated. But when it comes to establishing a pollinator garden in the world of tidy, chemically-coddled suburban lawns, the possibility doesn't seem that far-fetched. Just plant some flowers, preferably natives, get some larval host plants established, and the butterflies, bees, flies and wasps show up. How they found and find me still seems pretty magical. Sadly, in the 26 years we've lived here, the sheer numbers and the number of species have declined, but I'm not giving up just yet.

Good Sources of Information:

Emmel & Kinney. Florida's Fabulous Butterflies. World Publications. 1997.

Gerberg & Arnett. Florida Butterflies. Natural Science Publications. 1989.

Glassberg, Minno & Calhoun. Butterflies Through Binoculars: Florida. Oxford University Press. 2000.

Hall. Polydamas. entnemdept.ufl.edu/creatures/bfly/polydamas. This article is particularly informative. I tried to create a link, but had no success. You can find the article just by searching "polydamas" and scrolling to it.

Minno & Minno. Florida Butterfly Gardening. University Press of Florida. 1999.