January 27, 2000
For the millennium, I decided to take a small census. Over three days at the beginning of the month, I netted the monarch butterflies flying in the yard and counted them. I netted 28 total, of which 12 were female. At the beginning of the month, the temperatures were quite warm, averaging in the seventies and eighties during the day. Today, and for the past week, we've been victim of colder weather, with last night's low reaching just below 40 degrees f. With daytime temperatures in the fifties and sixties, the sight of a butterfly flying has been rare. Yesterday, I did see one gulf fritillary, but he didn't stay out long. The monarchs have not been flying for several days.
When the temperatures were warmer earlier, the larva were abundant. On Jan. 12 th I collected 25 fifth instar larva, Jan. 13th, another 30. From then the numbers began to decline with the colder weather moving in with an average ranging from a half dozen to a dozen or so every day or two. Part of the reason, I'm sure, for the declining number is that during the warmer days earlier in the month, the wasps as well as the ants were more active and undoubtedly collected a number of the smaller larva. Then also, with the cooler temps coming, fewer eggs were being laid. However, there are several chrysalis I've located hanging on some of the plants and under the eves of the roof which should emerge soon with a few warm days. I am sure there are a number more chysalis hanging out there, only better hidden.
Also, there are orange barred giant sulphurs and their larva present, zebra longwings and julias (I released these, but they seem to be doing fine), gulf fritillaries, now in fair number, but no swallowtails of any species nor have I seen any white peacocks for some time. The swallowtails are, I'm sure, overwintering at this time. I have some polydamas swallowtail chrysalis that are well over a month old now. I really don't expect to see them emerge for at least a month or two from now, perhaps even longer.
February 29, 2000
The past week, two of the giant swallowtails and two polydamas swallowtails emerged from their overwintering chrysalis. The weather has finally warmed, but earlier in the month, it was quite cold, well below normal, and except for a few hours on some days when the temperatures did rise above seventy degrees, the butterflies were a rare site. The monarch larva are now few and far between, primarily due to the fact that there were few eggs laid during the colder weather. With the warm days of the past week, they've been flying freely again, but are fewer in number than before and until a few days ago, exclusively males, that I observed. Over the weekend, I did finally observe two females in the garden laying eggs. With the warmth, I have also observed the wasps have become also more active.
The orange barred giant sulphurs are regularly seen and their larva are present. The plants are finally showing signs of growth and there are new shoots on the cassia in abundance. The Carolina willow I have for viceroys has new growth and awakened from its winter dormancy. Spring is springing in the backyard. I should have know that when the swallowtails emerged. In the north, people look for the arrival of the robins as the first sign of spring. Here, it is the first swallowtails.
April 1, 2000
The monarch larva have been surviving in better numbers for the past month even with heavier predation by our local wasp population. The reason, to my observation, is, more or less, that the current generation of monarchs has been producing a very large numbers of eggs. It has not been uncommon to find several eggs on a single leaf. The adults, as you may expect, are flying in significant numbers. I have observed several females laying eggs most mornings.
Much of the milkweed has just gone to seed, but many of the plants are still in flower. There still are many immature seed pods and, I am sure, more on the way. I have found a number of seedling milkweed sprouts around.
Other species I have sighted are giant swallowtails, polydamas swallowtails, orange barred and cloudless giant sulphurs, gulf fritillaries (many larva present currently), zebra longwings, an occasionally julia, and also red admirals along with a variety of smaller butterflies now appearing. All of the aforementioned species have larva present. I have not observed any white peacocks as yet, but I have seen a few southern whites also.
April 6, 2000
Most of us look upon the lady beetle or ladybug as a beneficial insect because they control aphids so well. They are, in fact, not so gentile and are first rate carnivores and also will take prey of opportunity as available if they consume all the aphids in the area which does happen, and happens more often that you may imagine.
Several times over the course of a year from time to time when the conditions are right, the aphid population will explode on the milkweed and other plants. During these times of plenty, the ladybugs will lay eggs and as the population of ladybugs increases, the population of aphids, as you would expect, decreases, until they are, in fact, eradicated.
Ladybugs are well known to take immature monarch larva and other prey if given the opportunity, but I discovered something yesterday I had never observed before and, quite frankly, was quite a surprise.
There are currently a small group of several monarch chrysalis under the eve of our roof. I noticed that two of them did not look right. I have observed deformities in chrysalis many times, but these looked a bit odd. Just below the cremaster, about half way down the curved cap of the chrysalis was a split on two of them. Usually, if when I've observed a separation in the chrysalis, usually indicative of a disease problem, the deformity is below the gold rim in the area where the wings are located and is a lack of closure during formation after molting. These splits were above on the curved top of the chrysalis.
With my curiosity peaked a bit, I grabbed a ladder to take a closer look. To my surprise, at one end of a split on one of the chyrsalis, was a ladybug munching away. I had never known ladybugs to be capable of or even interested in tackling such a large prey. It is akin to a bobcat taking down a walrus. Nevertheless, there the little ladybug was, working on its second dinner. Both attacked chrysalis were fully formed and hardened when I checked them, but it is hard to say they were hardened when the the ladybug started its work although they were certainly fully formed and there was no sign of seepage from the wound which indicates to me they were probably in at least a fairly dry state when attacked.
There are yet some aphids in the yard, but there are now very few compared to a few weeks ago. The ladybug larva that made it to the pupa stage are probably now emerging. This one did look fairly new. It certainly was hungry.
May 1, 2000
Amazingly enough, one of the two pupa the lady bug attacked healed and survived to emerge as a butterfly. The second one wasn't as lucky. The wound was too severe.
I have not observed any surviving monarch larva for several weeks now. Two species of wasps are on constant patrol and also the disease of last year has returned. I have found some dead larva under the plants. There are also parasitic tachinid flies in the area. I have found several dead pupa with the tell tale silk strands hanging down that their larva employ to lower themselves to the ground after fully developing.
There are still a very good number of adults flying, easily over a dozen may be counted at a single observation, and the females are still laying eggs. However, I now see a number of the small "munchy" holes in the milkweed leaves where the larva have hatched and either been taken by the ants or the wasps. They're not lasting very long.
Polydamas swallowtail caterpillars are now in good number, contently devastating the pipevine. There are giant swallowtails flying and eggs on the hercules club, but they are not eluding the wasps or ants. They disappear soon after hatching. They are probably being taken by ants. I see them patrolling the plant. We also have giant sulphurs and larva, but only the orange barred giants are around presently. I have observed red admirals flying, but only a few here and there. The eastern black swallowtails and white peacocks have yet to make an appearance this spring, but I have seen some southern whites and there are a variety of skippers now. Zebra longwings and gulf fritillaries are in good number.
July 20, 2000
Once again, I've been away from my stewardship of this chronicle too long, but, on the other hand, the previous report from May would do as well today as then as far as the survival of monarch larva is concerned. Since the last entry, I found only one solitary monarch larva that survived to the maturity of the fifth instar. I located it in the understory of a penta planting where several small milkweed plants were growing from seeds blown there. Apparently, grazing on the short plants, always near the surface of the ground and hidden in the plant understory, it was sufficiently concealed in an area where the wasps probably have difficulty negotiating flight. I named him "the lone ranger" and brought it inside to raise. It pupated the following day, but when it emerged a little over a week later, it did not appear to be healthy and the adult sadly died the same day. If it isn't one thing, it's another.
However, there are yet a good number of monarchs flying daily and there must be larva surviving somewhere. I can usually see up to a dozen flying during the day. There are eggs present all the time, but the small larva do not last long after hatching. Of course, if the ones that are surviving are clever enough to escape the attention of the patrolling wasps, I imagine they are hidden well enough from my view as well.
I still haven't seen any white peacocks this summer. It has been exceptionally dry this year and their larval plants grow along the edges of lakes and streams. I wonder if that has something to do with it. However, it has rained quite a bit recently and the lake is back up to its normal level. A couple of months ago, it was very low due to the drought conditions. Maybe we'll see again them soon.
August 30, 2000
The monarchs are still flying. I see several adults each day and there are also egg laying females. The larva, alas, are still not surviving to maturity that I have been able to locate, but I did find an adult that had freshly emerged drying its wings the other day, so there must be a few. They are just well hidden.
The white peacocks do not seem to be around this year. I have seen a total of three this month. At least, there are some flying now, but not many. The giant swallowtails, eastern black swallowtails, and polydamas swallowtails have been regularly present all month and laying eggs. I have seen a few palamedes swallowtails and I have red bay to attract them, but there have been no eggs or larva present I have been able to locate. I suspect that the odd palamedes paying a visit now and again may be male or, if females, found the red bays not to their liking for some reason. However, they are relative newcomers to the yard. Previously, before I put out the bays, there were none. Orange barred giant sulphurs are the only giant sulphurs present currently, but some of the cassia is going into bloom, so that may change. Zebra longwings and gulf fritillaries are fairly abundant now. Of course, I have planted more passion vines over the years.
I am going to try a little experiment. Over the next few days I am going to net the adult monarchs flying here and release them elsewhere and see, once the yard is empty, what happens.
September 18, 2000
I removed the monarchs I could find from the yard a couple of times. I netted 10 and 8 respectively, but there were always still several flying the next day, so the population as far as adults seems to be holding. With all the milkweed now planted here and the flying adults wafting pheromones into the air, they probably are lured here from some distance. The reports from Monarch Watch <http://www.monarchwatch.org> on the fall migration have been coming in. The monarchs are now moving south from the northern states. The ones in my backyard, evidently, aren't going anywhere. They are already where they want to be.
I have seen a few larva finally. Not many, one here, one there. The wasps are still very active. If this year follows other years, when the milkweed blossoms this fall and when the seed pods appear (they only seed in the late fall/early winter months here for some reason), the larva should begin to survive in larger and larger numbers.
Finally, the white peacocks did show up and I collected some eggs on the water hyssop I have in a couple of hanging planters and I now have a few caterpillars. Green shrimp plant, a common weed most people yank out of their lawns, is also a larval host for them. There are eastern black swallowtail larva on the parsley (I moved them inside to protect them), giant swallowtail larva from the wild lime, polydamas swallowtail larva from the pipevines, and palamedes swallowtail larva from the red bay. This is the first year we've had palamedes lay eggs here. I placed several small red bays (3 feet tall) in pots around a bed of the red pentas. I sighted a palamedes a few weeks ago and she laid two eggs while visiting, one on each of two plants which I brought into the porch for protection. One is now a chrysalis and the other is almost full grown.
October 5, 2000
The adult monarchs are still flying as we approach my unofficial day for the arrival of the northern migration which is Columbus Day. I have observed females laying eggs regularly, but there are as yet no surviving larva I can find in any significant number. Incidentally, if you found your way here from the Audubon Society's Birding and Butterflies Festival's website, welcome. It seems the web designer place a link to this site on the page for the festival concerning Dr. Lincoln Brower's appearance speaking on monarchs.
I am monitoring a couple of wasp nests to see if I can detect when they go into winter hibernation. At this writing, they are still active, but I did find one nest that was abandoned and had a couple of dead wasps sticking to it. I did not spray the nest. I do not know hat happened to them, but there are three dead wasps from, I assume, natural causes, and the nest is abandoned. I am watching two other nests. We'll see what happens.
One note on the milkweed. At the present, the aphids are on the rise. There are quite a few lady bugs here already and their larva are present, but the aphids are multiplying to significant numbers again.
The white peacocks are now flying is fair numbers and I see them daily. The eastern blacks have disappeared, it seems, from my back yard. I have seen a spicebush swallowtail or two fly in now and again, and did raise and release a couple from eggs collected on the red bay this summer, my first. Nice to see a new species here in the yard. I had earlier thought they were palamedes, but it appears they were spicebush swallowtails from their appearance after emerging.
October 24, 2000
Columbus Day, my unofficial day the winter migration arrives, came and went without anything significant to report. The monarchs have been continuoisly flying this year throughout the fall months. There are a few new monarchs flying along with some that appear to be older. I have found several 5th instar larva this past week and there is at least one new chrysalis under the fronds, if you can call them that, of the screw palm. The fronds of the screw palm are several inches wide, rigid and smooth, and offer the chrysalis good protection. I always find several attached to it each year. This one is the first of the fall.
The aphids on the milkweed are very, very thick now. They have been undergoing another population explosion. The lady bugs are also now multiplying to more significant numbers and their larva are quite numerous. I've also observed the hover fly larva now are present in considerable numbers. It will be a while before they can eat all the aphids though. I lost count of the aphids at one million plus. At the moment, the aphids appear to be still out multiplying the lady bugs and hover flies, but it is only a matter of time until the balance shifts. There are many new lady bugs emerging from their pupa now. Significantly, the aphids are also pupating.
Aphids are very interesting in that the multiply two ways. The aphids you usually see are really the larva, in this case, a nymph, stage and are all female. They multiply by bearing live young and skip the pupa and adult stage, an incomplete metamorphosis. In the late summer or fall when the days become shorter and the temperatures cool, aphid larva form pupa from which winged true adults will emerge, male and female, which will reproduce by mating and the females laying eggs, a complete metamorphosis. The pupa are small, well ... about aphid sized, brown, and hardened as protection against predators. They resemble small roundish seeds attached to the underside of the leaves or on the stems. As I write, the aphids in the backyard are beginning to form significant numbers of pupa. Since it is only a matter of time before the lady bugs and their allies wipe out the aphid nymphs, as they form pupa, their infestation should significantly decrease since they will no longer be multiplying by live birth. Of course, the eggs they will produce are another matter. We'll see ... so far the score is: Lady Bugs and Hover Flies - 322,456, Aphids - 2,135,364. It is the top bottom of the sixth inning with the away team coming to bat.
While taking a little break away from composing this entry, I came upon a newly emerged male monarch struggling to climb up a plant in the garden. He was in a little trouble, trapped in a little thicket that would not allow him to fully spread his wings and every time he tried to fly, he would fall back deeper into the weeds, so I got him to walk up on my finger and when I had him up a bit, he took off into the wild blue yonder. I always find the fall the most interesting time of the year with the monarchs.
The fall migration is in full swing and the larva will now begin to survive in higher and higher numbers in my backyard. The wasps, though still active, will soon begin their over winter dormancy. The aphids are pupating and the milkweed plants are forming seed pods. They seem to know what is coming.
I have always found it mysterious the larva in the winter are so numerous and in the summer survival is slim. Aside from the predation by wasps and other predators like assassin bugs, the larva during the summer months seem to attract disease and many larva and pupa escaping the wasps die as a result. If you have read through some of the earlier years, you will find I have speculated as to the cause of the disease on a number of occasions, but now I am beginning to think something more sinister is at work. The root cause may be in the milkweed plant itself. The species planted here is Asclepias curassavica, commonly known as tropical milkweed, mexican milkweed, scarlet milkweed, and probably a few other names like butterfly milkweed which is on the label from American Farms in Naples, FL, which grew a number of the plants I have. A curassavica is the most common milkweed species sold for butterfly gardens by nurseries here. It is also know to be very toxic as compared to common milkweed up north or other native species (A. curassavica is not native, but now so widely planted, it is considered to be naturalized.).
It may be simply in the summer with more sunlight hours, more water and humidity, higher temperatures, etc., these plants may simply be winning their battle with the monarch larva by poisoning them. In the spring, I have to be wary of contact with the sap, especially near the eyes, as I have quite an allergic reaction to contact with it, but in the winter, this goes away. The coincidence did not occur to me until just now, but my eyes are like the bunion on the toe of someone, in olden days, that was said could predict the weather if it acted up. When the weather gets warm enough for me to develop a sweat while working in the garden and I rub my eyes with just a little sap on my fingers, the effect can be dramatic, so be careful out there.
In the fall and winter, the plants put their energy into producing seed and coupled with the shorter daylight hours, cooler temps., etc., resulting in slower growth, must become, I surmise, less toxic which permit the monarch larva to consume the plant with impunity. Well, it will take me another year to actually figure that out. I will need to collect some data. If A. curassavica's toxicity is not constant, but variable under changing climatic conditions, then it may hold that the species is an excellent food source for winter larva, but not for summer larva here in Florida's climate I should think. Golly. Milkweed really doesn't like being eaten after all. It seems they, in fact, can also do something about it. Nasty little plants, milkweeds. Ya gotta love them to appreciate them. Then again, I could be wrong. It wouldn't be the first time.
December 30, 2000
We are just past the winter solstice, December 22, the shortest day of the year. The temperatures have been below normal here for several weeks now and we have avoided a freeze thus far (we did hit 34 degrees a couple of times though) and the milkweed growth has been slowed to a crawl. With the daytime high temps rarely reaching 60 degrees (our norm is above 70 at this time of the year), and more usually in the fifties, we are unseasonably cold. In spite of this, I have seen the adult monarchs flying for short periods on the sunnier days, but they fly only a short while and then stop to bask to get up a bit more warmth. Inland from here, the temps have been reaching well below freezing and I suspect considering the length of time of this cold spell as well as the severity of the temps (a lot of twenty degree nights north of here), the butterfly population in the northern/central sectors of the state (we are midway - right about on the current freeze line which is only been about twenty miles or so north of us on these cold nights - we are also surrounded by water - Tampa Bay to the east and the Gulf of Mexico to the west - which keeps us just a little warmer) is suffering very high mortality. It is a natural occurrence. There isn't anything you can do. Above the freeze line, there are no plants left either. They are either killed or damaged and will need time to recover..
However, the milkweed in my backyard is still viable. So far, damage has been minimal, and there are a number of larva present, but fewer it appears than last year at this time. Due to the cold, they are progressing very slowly, but I have observed they are still eating and growing in spite of the lower temps, but they only appear to eat during the warmer, sunnier daytime periods and stop during the cold nights. I have observed them sunning themselves on the top surface of the leaves to pick up extra heat from the solar orb. The smaller caterpillars may not be surviving the weather conditions. They do not have very much mass and dehydrate more quickly if they are too cold to feed sufficiently. Hatchlings are particularly vulnerable.
True to my observed annual cycle, the larva are now surviving and producing apparently healthy adults, but there still is a small percentage of mortality among the larva now emerging as adults from early December. We'll see if this situation evaporates for the January larva like it did last year. That is, if, in the meantime, it doesn't freeze.
Happy New Year.
We will post further observations as warranted.
Thanks for visiting.
Dale & Peggy McClung