Been a while since Colony Collapse Disorder (CCD) has been exercised here at Corrente, and there is good news and bad news – of a sort.
The good news is that things don’t appear to have worsened. The bad news is that things don’t appear to have improved and there is still no clear consensus about what is going on. An update from Randy Oliver, a professional beekeeper, reviews the many things that have been blamed from cell phones to mites to viruses and concludes that none of them are enough of an answer alone to explain the phenomenon. In a two-part series, he explains the absence of dead bees around collapsed hives as the natural course of events for worn-out gatherers – they literally fly until they drop and most of the time that will be far from the hive.
With greater research into old records it has been documented that events similar to the current CCD have occurred before, although not apparently to this extent either in the widespread nature of the current incidence nor the magnitude of loss. It may be that the current phenomenon is merely a new manifestation of an established cyclical decline in honeybee population, exacerbated in real terms by progressively greater stress due to economic demands of a longer growing season and increased trucking of hives from crop to crop, plus an artificial heightening of awareness due to better communication and documentation abilities of the modern high-tech era.
It is possible that this higher-than-normal periodic die-off is similar in pattern to rogue waves in the ocean, where a confluence of forces results in a magnified effect from functionally natural events that individually are much smaller.
For the curious, this series by Oliver contains a clearly presented wealth of basic information on applied apiary science and practical hive management. With only a couple of caveats* this is an excellent primer on Colony Collapse Disorder and the nuts and bolts of honeybees. Highly recommended, if the topic is of interest.
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* Those caveats:
Oliver states that inspired oxygen is converted to water. This isn’t strictly true. As with all O2-breathing animals, inspired oxygen is transported to cells where it provides energy through the process of oxidative phosphorylation. From a mass balance perspective, the oxygen intake is balanced by carbon dioxide exhalation and typically the two are considered linked. In practice, it is impossible to identify exactly which oxygen molecule goes where within a cell and since water is also a byproduct of the breakdown of carbohydrates and oxidative phosphorylation the precise fate of inspired O2 cannot be assigned.
Oliver also engages in a bit of speculation about the effects of lowered O2 levels in hives during the winter dormancy period and the effect that may have on damage from free radicals formed during periods of excess oxygen levels. Missing from his speculation is any discussion of respiratory drivers.
Honeybees, like humans, manage their respiratory rate in a discontinuous and variable fashion. The principle drivers are a need to reduce expiratory water loss that tends to minimize the number of breaths, and management of carbon dioxide levels in haemolymph, the bee equivalent of blood. Both of them tend towards lengthening breath intervals at rest, while during exercise CO,sub2 production causes increased breath frequency.
The diffusion drive for oxygen in is so much greater than for carbon dioxide out, by a factor of a thousand-fold, that only rarely will haemolymph or tissue oxygen levels become a controlling driver; insects, like humans, can function well although with less endurance at O2 levels half that of sea level.
Only for brief periods immediately after cessation of exercise will oxygen levels be present in concentrations where free-radical levels can be damaging, and for honeybees that damage is not usually the rate-limiting step in their survival. For most of them, the end comes when their wings wear out and they can no longer remain airborne.
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feed your bees!
and don't give them any of that high-fructose corn syrup crap either.
i l-o-o-o-o-o-v-e reading about metabolism [and waves]. you just have no idea. thanks.
when i first moved to this side of town, we had lots of bees flying in and out of the flowering parts of the landscaping. now, not so much. the disappearance seems to have roughly coincided with the 2004 and 2005 hurricanes, but i could be misremembering.
a 500-mile warranty, eh? i've been watching the monarchs coming through here on their way down to mexico the past few weeks. i haven't given up hope, yet, of catching a whole roost of them on film [ok so i'm still living in the dark ages]. i saw one out at the beach many years ago -- from a distance it looked like an entire stand of pine trees had died overnight, but when i got closer i saw that the trees were completely covered, no exaggeration, in butterflies.
i won't swear to it, but i think cell phones kill bees is how i found corrente in the first place.
quite welcome, hipparchia
and thank you for reading and commenting.
Monarchs are lovely things. Yours in western Florida is an interesting population, about which little of certainty is known. Could be all residents who gather in colonies to overwinter, or they could be migratory or they could be mixture of both, a way of providing alternative survival habitats while preserving genetic diversity. We just don't know.
The Western population of Monarchs winters in several spots from central Mexico in the EcoPreserve all along the Pacific coast up to Monterey an hour from me, Pacific Grove actually, the northernmost winter colony formation IIRC. Our population fluctuates and had sunk to record lows but since a program with schoolchildren to plant milkweed started a couple of decades or so ago the population has rebounded and is now quite robust; there may or may not be a link, but don't tell the children.
Since you like things scientific this might please you; it does me. Just this past year the probable mechanism for migratory guidance in the Monarch has been pinpointed, a molecular guidance system controlled by a series of proteins that require 24 hours to complete a circular series of synthesis and destruction. Two of the proteins, CRY1 and a new discovery, CRY2, are linked in interesting ways.
CRY1 is quite ancient, originating before the split of life into plant and animal; it is found in phototrophic plants and in animals from the fruit fly on up the chain. CRY2 is of later origin, specific it appears to animals only, but still quite old; the protein in Monarchs is almost identical to a protein with apparently similar function in vertebrates.
It may be that the same protein clock that orients Monarchs also causes jetlag in humans; we are not equipped to deal with traversing so many time zones in a single day and thus become disoriented. I find that perversely delightful.
You can read a very decent overview of the work here, with links to the actual articles themselves.
Oh, and did you know that it is possible, with sharp eyes, to distinguish male from female Monarchs on the wing? A wonderful trick to teach others, if you don't already know it I'll show you how.
perverse delights
cool! i've always wanted to be a monarch. yes, i love this stuff -- protein folding! reaction kinetics! dy/dx! forbs! my tastes are catholic.
how do they do that?! i've been fascinated for as long as i can remember with the navigational abilities of migrating critters. unlike the stoopid id-ists [i wish there were some way to make michael behe stop referring to himself as a biochemist], i'm not willing to write anything off to 'irreducible complexity' -- i want to know everything about how life works, down to the last subatomic particle. speaking of old, i would give a lot to be able to stay alive for several centuries, keeping up with all the scientific discoveries, no matter how old and decrepit i might get.
i'd heard we were special ;) here on the redneck riviera. i went back the next day, at the same time of day, this time with a camera, and while there were still lots of butterflies around, it was nothing like the day before. nor have i seen anything like it in the years since, but i keep making the trek out there, just in case they come back.
just from what i've seen in the way of monarch numbers, i'd guess ours are a mixture of those who stop over on their way further south and those who decide this is a lovely place to stay [it is, btw] but that would be purely anecdotal. otoh, hummingbirds and piping plovers seem to have adopted a similar strategy, with some of them living here year round [or stopping here for the winter] and others of their species resting briefly, then moving on.
well of course those kids planting milkweed is what saved your monarchs! but they're amateurs, i used to plant nettles to help save butterflies.
i suspect a setup here, but ok, i'll bite -- how does one tell the boyz from the grrrlz in monarchs?
"irreducible complexity"...
... makes me think of derivatives.
[ ] Very tepidly voting for Obama [ ] ?????. [ ] Any mullah-sucking billionaire-teabagging torture-loving pus-encrusted spawn of Cthulhu, bless his (R) heart.
"First they ignore you, then they ridicule you, then they fight you, then you win." -- Mahatma Gandhi
not even god...
...is going to be able to decode those.
OK, BIO, share the Monarch sex differentiations secret!
Thnx!
Sexytime with Monarchs
Males have a distinctive black spot on one of their hindwing veins, while females do not. These spots are scale-covered glands that express pheremones to attract a mate.
When Monarchs fly, they almost always pause for a moment at the end of the downstroke, with wings fully extended, to glide for a ways. That fraction of a second is enough to register on human eyes, and the black spots are easily detected at 20 meters. With the right light and some practice they can be perceived at even greater distances.
There are other differences, females have broader vein markings and more distinct spots on their outer wing margins, while males are slightly larger with claspers at the end of their abdomens. None of those are easily seen on the wing, but those black spots are like headlights once you've tuned in your memory to them.
Now you have to pass it on, jawbone; knowledge is only worthwhile if it's shared.