Jan. 12, 1998
A new year. Monarch butterflies are present as usual at this time of year in substantial numbers along with Giant Sulphurs, some Cloudless, but mostly Orange Barred, Gulf Fritillaries, and Giant Swallowtails. There are a smattering of other butterflies in the yard, but only occasional sightings, a skipper here, a zebra there. The days are getting longer now and the sun a little higher each day in the sky, so the plants are beginning to grow again. More food. Yum. Yum.
Do you know how to tell a Monarch Butterfly that migrates to Mexico from one that goes to Florida for the winter?
The Monarchs migrating toward Mexico can be seen wearing little sombreros and the Florida bound seem to be a bit tanner and usually are wearing sun glasses.
Trust me.
Feb. 3, 1998
Actually, as I reread that joke, I must say its pretty bad. Everyone knows the Florida butterflies are not really tanner, but identical in appearance except for the shades.
Over the past three weeks, I counted at lease twelve individual Monarch females laying eggs here. A male has taken up residence and has been on patrol for over a week now. We had a series of very violent thunderstorms here overnight and I feared he would not survive, but today, despite a high wind, he was out there checking things out. He was flying his circuit. At times he flew straight through very high wind gusts to reach the windward boundary of his territory. I watched him make headway flying into a wind so steadily strong, it has been knocking down good sized twigs and air plants from our Oak trees all day and dozens of large palm fronds are on the ground. The weather report was sustained winds between 13 and 30 m.p.h. with gusts higher at times. He has been attacking the wind like an air sailor. He manages to knife his way forward through the rapidly moving air. It appears as if he knows how to tack. I was impressed. I've named him Atlas.
Giant Sulphurs, Gulf Fritillaries as well as some skippers are present daily. There is also a Giant Swallowtail that has been visiting regularly for some time. We have a wild lime tree planted which is a host plant for the species. I believe he is a male and we are part of his territory. He ranges much farther that the Monarch does. His wings are showing a great deal of wear now. Well, we'll see if he has one more fling left in him soon. We have some Giants in chrysalis should begin releasing them in a few days. We've managed to raise and release a number this year.
Once Pinellas County, Florida, was populated by a large number of orange groves. To an orange grower, the beautiful Giant Swallowtail is not a welcome visitor as the caterpillars feed upon citrus leaves. It makes no difference to the swallowtails if it is native wild lime or a highly developed hybrid orange tree developed for optum fruit production which is obviously going to be less if too many leaves are eaten by "orange dogs" as the growers call them. There are very few orange groves remaining now. They were paved over to make parking lots for shopping centers here long ago, but it is nice to see my friend visit now and again as I know there are still Giant Swallowtails in the neighborhood despite the destruction of habitat.
Feb. 15, 1998
The Monarchs are certainly present. I find eggs and larva daily. I've counted over a dozen individual females laying eggs over the past few weeks. Atlas, the resident male, is still flying. He is always on patrol when the weather permits. Today is rainy. No butterflies are flying.
The Giant Swallowtail got lucky the other day. I saw him coupled with a female. He was flying her around while he fed on pentas. She has stayed in the area after the mating. I've seen her several times.
On a more bizarre note, I noticed that some of the milkweed was being eaten, but in a different way and there were no caterpillars on the plants I could find. Then, the other morning, I spotted the culprit. It was a fruit rat. He was boldly out there munching away on milkweed during broad daylight. He didn't seem to be afraid of me when I approached as he ducked for the cover of the pentas and then returned momentarily to munching the milkweed right in front of me. I thought that perhaps this must be a young (and pretty stupid) fruit rat to be eating milkweed, but he seemed to like it and appeared unaffected by the toxins as he came back the next day to chow down again. Well, I love all of nature's critters, but I tend to draw the line with rats, even cute little fruit rats. However, I didn't kill him, I just let the cat outside. As she went in one end of the pentas, he scurried out the other. She couldn't catch him if she wanted to. She's too fat and about as stealthy as a walrus, but I haven't seen the little guy since so he either decided the risk of being eaten by a cat outweighed his desire for milkweed or he finally developed a bellyache from all the leaves he ate. Either way, he is elsewhere which is fine by me.
March 16, 1998
The Monarchs are plentiful. Just as the milkweed begins to recover from being munched back to sticks by one group of caterpillars, the starter leaves begin to disappear. This makes at least the third time this winter they have been completely pruned by the caterpillars. Yes indeed, larva are present. And even with the meager servings, a good number are reaching maturity.
There seems to have been a changing of the guard. Atlas, the old male, is not to be seen and a younger one now cruises his old haunts. The Giant Tiger male seems to have a replacement now as well.
We spotted a new butterfly here yesterday. It is fairly large, swallowtail size, and the wings were very solid dark blue or black with large white areas covering about 75% of the hind wing. It was flying in the tops of the punk trees in our neighbor's yard, and we we unable to see smaller markings at the distance.
May 18, 1998
Its been a while, but no new news insofar as monarchs. They are plentiful still, perhaps even more so than earlier in the year.
However, thanks to the efforts of a friend to who sent me a few zebra longwing caterpillars which we managed to raise and release, there now appears to be a resident zebra population in the neighborhood at the moment. These may not be related to my released zebras, but I have identified three individuals, two seen simultaneously and one seen with a large piece snapped out of his wing by what appears to have been a bird beak. Three is more than I have ever observed here. We'll see.
July 8, 1998
I have noticed a marked drop in monarch caterpillars beginning in early June. After observing predation by at least two species of wasps, I brought a few of the surviving caterpillars in and began raising them under protection. A number of them died, apparently due to a disease present. The caterpillars ceased eating and simply died in their tracks, and of the survivors, several, but a much smaller proportion of the remaining population, also died as chrysalis. A few of the adults emerged weak, but most that made it that far appeared strong. Last week I discovered about two dozen mature caterpillars in the garden and while they all did form chrysalis, a few died.
It has been very hot here breaking records left and right, especially for June. Hot and humid is the preferred atmosphere for protozoa. The adult monarch butterflies are still present and laying eggs, but few, if any, caterpillars are reaching maturity at present. This is July and the monarch butterfly for the last two years of observation have began to disappear around the end of the month or into August, gone entirely the month of September, not returning until mid October. Where do they go for the month of September? Do they go anywhere? Maybe they all simply die, replaced in the fall by southern migrating butterflies. They are absent for longer than one generation, at least eight weeks (56 days), maybe a bit longer. Right now, from egg hatching to emerging adult is less than 22 days.
Our species list has grown this year. In our garden, I have seen zebra longwings, giant sulphurs, giant swallowtails, gulf fritillaries, white peacocks, a number of skippers and hairstreaks, polydamas, eastern black swallowtail, and a few queens as well as the monarchs. On a warm, sunny day, the garden can be very entertaining.
July 23, 1998
There have been no monarch larva for two weeks, save one I found about half grown. I gathered a few leaves with eggs on them, but the eggs did not hatch. It has been humid and they may have been killed by fungus or were possibly infertile, I don't know, but they failed to hatch nonetheless. The disease seems to also be present among the swallowtail caterpillars and also the giant sulphur caterpillars as I've observed them dying with the same symptoms. I noticed that when the monarch caterpillars died, they often lost fluids from the mouth and anal openings. When I collected a slide of the fluid and placed it under a microscope, I saw definite bacteria present. Whether this is a non harmful, natural bacteria from the digestive tract or is, in fact, the culprit, I can not say, but they're there. Between the wasps and the disease, in my backyard, there are no monarch caterpillar survivors I can find. The adults are still present and there are now a few new females in the area, so we'll see. We did release two eastern blacks and a few more sulphs this week. They aren't all dying like the monarchs, but my guess is at least half are not making it, probably more.
Sept. 11, 1998
The milkweed is now in full bloom. I have not observed a flying monarch adult for several days now. It stands to reason with no larva surviving. The wasps are present in strong numbers and I suspect they are the chief cause of the population decline, but possibly not the entire cause as usually I will find a few caterpillars they miss. I have not seen any zebras either, but the giant sulphurs, fritillaries, polydamas, some skippers and giant swallowtails are flying. I collected some eggs and caterpillars of polydamas from our pipevine. One caterpillar of six died. I suspect it died of the disease which I finally believe I have identified as a virus, most likely a nuclear polyhedrosis virus which is a subgroup of baculoviruses, and apparently is present on the plant leaves. From what I have been able to find out, it must be consumed by the caterpillar in order to infect it, and once infected, it will usually die during the caterpillar (larva) stage. How it got here, I have no idea. If you are raising butterflies in captivity and encounter the problem, the food leaves can be and must be sterilized. Otherwise, get out your bugle and practice up on taps. You'll be playing it fairly often.
If I don't observe any adult monarchs from now on, it places their disappearance this year around Labor Day.
Incidentally, the cassia, in particular, cassia alata, which is favored by the giant sulphurs, is now also in bloom. The flowers are fairly large spikes of individual bright yellow blossoms and the blossoms bring one particular species of giant sulphur simply called the "Large Orange Sulphur," Phoebis agarithe maxima. The caterpillars are yellow (like the blossoms) with black bars across their back and I have found several over the past few weeks. The caterpillars of the other two species we attract are green and feed on the leaves. This yellow fellow only feeds on the blossoms and the immature seed pods. It doesn't touch the leaves. How it survives the rest of the year, I have no idea. The cassia only blooms in the fall. A book I have lists some other larval host plants for this species: blackbead, cat's claw, and wild tamarind (not cassia incidentally), so I guess it survives on them until the time is right for the cassia. We are also apparently at the northern limit of its range as it is listed a tropical and occurs in South Florida, The Keys, and, um, it seems, in my backyard when the cassia is in bloom.
September 18, 1998
I sited a female monarch who was nectaring a few days ago. She appeared new and did not lay eggs that I could observe. She did not remain. The following day a male, also new in appearance, showed up, but likewise, did not remain. When a female comes in, she may or may not remain, but a male, upon finding all the milkweed unguarded by another resident male, usually sets up a territory and sticks around. This one flew around for only the day, then was gone. Since, I have seen no more. There are no larva present. There hasn't been for well over a month now.
November 21, 1998
Once again, I've been away from my duties here too long, but there hasn't been any real real change in the situation until now. October 12th, Columbus Day, was the first siting of the fall for the past two years, but this year the Monarchs maintained almost a constant presence, although in minimal numbers, throughout the period. The weather has been unusually warm for us here and that may be the reason, but until last week, no larva were observed reaching maturity. I found one, the first one of the season, mature and fat. and I assume he crawled off somewhere to pupate as he had disappeared the next morning. Since, I have noticed a few more smaller larva, but, with the weather warm, the wasps are still active, although I believe they are on the decline in numbers as I seem to see fewer and fewer all the time. The numbers of adult Monarchs have also recently increased as I counted eight yesterday. They had previously been sited only in ones and twos. The milkweed is going to seed, although, as I write, no pods have matured as yet.
We have also now caterpillars of giant sulphurs, both Cloudless and Large Orange Sulphur, although not on the cassia alata, which has gone to seed at the present time, but another species of cassia we have planted and has been in blooming until now (the cats ate all the blooms), as well as Giant Swallowtails and Gulf Fritillaries (also wasp victims until recently).
The monarchs are definitely back. Their flying number is now at least to squadron, perhaps wing, level. It is easy to count ten or twelve flying at any one time. The larva are beginning to survive to maturity although the warm weather has kept the wasps also flying which is keeping their numbers down somewhat, but they are now outproducing the predation, and I counted over two dozen mature caterpillars over the past week or so. I counted no fewer than 100 eggs on plants in a short time yesterday much to the chagrin of the poor, unsuspecting milkweed. However, the milkweed is also now rapidly going to seed. It appears the plants know what is coming and are bailing out ... literally. The mature caterpillars will not only consume the leaves, but also are quite capable of eating (and do eat) the seed pods, and, at this point, a couple have been munched, but most are yet OK and about half have burst open. Interesting timing.
We also have six giant swallowtail caterpillars I brought in to protect. I collected them as eggs and they are about 75% grown. If there were any eggs outside that I missed, and I'm sure there probably were, none have made it that I can locate. There are also a number of polydamas larva on the pipevine and orange barred giant sulphur larva on the cassia.
We will post further observations as warranted.
Thanks for visiting.
Dale & Peggy McClung
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