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TL:DR – The Blackcap, Sylvia atricapilla, is commonly a summer visitor to the UK from sub-Saharan Africa. But in recent years, some birds that spend their summers in the east of Europe and would normally head for the Iberian peninsula or North Africa in winter have reached the UK where they found winter food on bird feeders. There is now evidence that these birds that overwinter in the UK are not mingling with the Iberian or African overwinterers when they go back to their breeding grounds in east Europe.
UPDATE: As of 13th March 2023, the male Blackcap that overwintered since mid-December in our garden is still here. The outside temperature has gone from freezing to about 17 Celsius, but he is showing no signs of departing just yet. He enjoyed mistletoe berries, pyracanthus berries and now most of those have gone, he pecks at suet balls in a feeder right outside our living room window.
It’s no wonder this little fellow looks so grumpy perched next to the mistletoe growing on our rowan tree…most other Blackcaps will be enjoying a much balmier winter on the Iberian Peninsula or even in Africa. We have had Blackcaps in our garden in winter for several years now. Never see them in the garden in summer though. We had a male and a female last winter. So far this winter, just this solitary male.
Blackcap overwintering in the UK
In recent years, a lot of migrating Blackcaps (Sylvia atricapilla) have headed west from eastern Europe for the winter instead of turning south. Their compasses seem to have lost calibration, perhaps due to climate change, but other factors may be at play. The species seems to be affected by climate change, a decalibration of their internal compasses, and perhaps moreover by the British wont to stock garden bird feeders and put out fat balls, which is not such a common practice on the continental mainland.
When they head back to their mating grounds in the spring, they are marginalised by the southerners it seems and two distinct groupings are observed. This is an early process in speciation whereby in the long-term we might see a sub-species emerge that no longer mates with the other.
TL:DR – I compiled a sampler for a newbie birding book with ten chapters, but I am yet to write the remaining 90.
Back in August 2017, I was all hyped about putting together a new book. It come up with a title, Chasing Wild Geese, and the plan was to write a short piece about the hundred birds a novice birder might “tick” first in the UK. Each item would be illustrated with one of my photos of said bird.
Chasing Wild Geese, the gosling feather book cover
I put together a taster, with the first ten written and formatted and even did a spoof bio page in the same style about yours truly.
I gave the cover a silly acronym: FEATHER. This stood for “Food Environment Aural Type Habitat Etymology Resemblance” and was a summary of the contents of each page.
I shared the sampler widely on social media and estimate that between six hundred and a thousand people downloaded the PDF file from my website. It’s still available if you’d like to take a look, here. I spoke to my publisher and ideas were batted back and forth. Ultimately though, the likely costs of producing a full-colour photographic book of this sort we agreed were likely to have been prohibitive at the time, so sadly, I put the Geese on the backburner and turned my attention to other writing, photography, and more songwriting.
In the meantime, there have been several similar books on the market from far more expert birders and better photographers than me, any one of which would easily have outsold the honking Geese. I do now have better photos of all the birds in the sampler, and at least a couple of hundred other birds that might have featured in a follow-up…maybe if I stop chasing it, it will come home to roost. We’ll see…
TL:DR – Fundamentally, starlings murmurate because they enjoy it, it’s instinctive behaviour, but there will be reward feedback loops in their brains that drive the behaviour that’s almost beyond doubt. But, the phenomenon is in their instincts to help protect them from raptor predation.
I’ve talked about Starling murmurations several times before here. They are a fascinating, exciting, wonderful natural phenomenon with a lot to teach us about animal behaviour and perhaps even fluid flow! There are two spots on the outskirts of our village here in South Cambridgeshire where you might see a murmuration.
There is a reedbed in the balancing pond that supports drainage from one of the housing estates and then there’s a similar pond on the edge of the local recycling centre (rubbish dump). I’ve mentioned the Red Kites that frequent that site too in an update to an old article. It was while seeking out and finding 20+ Red Kites a couple of weeks ago that I noticed the Starling numbers were building on the same patch, with two to three flocks of several hundred birds swooping around the farmland that abutts the dump.
We walked there again yesterday so I could photograph the Red Kites again. We saw at least 20, along with a couple of hundred Redwing and dozens of Fieldfare, and a Buzzard harried by the Red Kites. There were a lot more Starlings, three fluxional flocks of several hundred each. At one point, hundreds were in the hedgerow when a raptor interrupted their chirruping and chatting and they whooshed into the air en masse and murmurated to distract and confuse the bird of prey.
I got a few photos one of which shows a large flock moving in unison. I estimate about 1500 birds in this photo and there were perhaps two other flocks of maybe about a half to two-thirds the size. I’d suggest that this patch has at least 3000 birds. It will be worth another visit towards dusk to see them bed down to roost among the reeds, also might be worth getting up at dawn to see them rise as a single mass from their roost. My estimate of 1500 in this photo was corroborated by a proper birder friend with far more experience of counting than I.
TL:DR – Anecdote is not evidence, but I feel like I gained some benefit from taking a multivitamin supplement, it probably compensated for poor absorption of iron and perhaps other vitamins caused by one of my prescription medicines.
I’ve always been wary of taking vitamins and other supplements. There are good reasons not to do so, if you have a reasonably balanced diet. Excesses of some vitamins and minerals can lead to problems like kidney and liver damage, kidney stones, and some can interfere with the absorption and activity of prescription medicines.
However.
I have been feeling rather tired in recent months, becoming unaccustomedly exhausted after even light activity. I’m talking after a short walk, but sometimes even just after a shower. Was it long-COVID, was it my medication, was it just me getting older?
Mrs Sciencebase had an iron and vitamin supplement for an unrelated reason and suggested I try it, see if it would help.
Well, I took the recommended dose for a few days, not expecting to experience much improvement. Amazingly though, I felt a remarkable change in what people commonly refer to as “energy levels”. Activities that had started to become a tiring chore became a lot easier, I hopped on my bike and did a decent half an hour’s cycling without breaking a sweat, a couple of days after that I did an hour, at speed, and aside from being thirsty when I got back to base, I was fine.
I know anecdote is not evidence, but honestly, it seems like too much of a coincidence that I felt like I had recovered from apparent chronic exhaustion within three days or so of taking the supplement. Moreover, when I look at the side effects of one of my medications, it does suggest that tiredness and various other side effects are associated with reduced absorption of micronutrients (vitamins and minerals). So, I’m sticking with the supplement for a while longer.
Intriguingly, the effects do not seem to have been wholly physical though. Most people have had a tough few years, but there has been significant family loss and stress here that happened in the middle of covid, is ongoing, and I have not been what you might call the happiest bunny in the warren, for a long tim, I must confess. Stuff that I usually really enjoy has not, on too many occasions, brought me much joy in recent months. I shrugged it off as being the grief and worry…but…a few days ago, I felt like the proverbial cloud had lifted, and even though it was a drizzly day, the sun seemed to be shining again.
Could this too have been a supplement fix? Well, there are many, many biochemical pathways that are linked to mental health, disturbance in some of those are known to be connected to depression. These various pathways need various micronutrients to work properly. Might I have been deficient in an essential biochemical component? Have I now replenished my supplies and rebooted those pathwats?
Perhaps the brain, when faced with deficiency, goes into some kind of lockdown to make you mope, reduce motivation, and so activity? And, when that lockdown is prolonged and deep, could it also begin to impinge on other pathways to the detriment of mental health. If so, I wonder if this is exacerbated in the wake of a double-dose of grief accompanied by a lot of not unwarranted stresses and anxieties.
I don’t know. Like I say, anecdote is not evidence. I’d rather not take the supplements for a prolonged period of time, so I will be having a chat with my doc at my annual review about my current medication. I will tell them that what I do know is that I’ve been taking a daily dose of micronutrients and feel physically much fitter than I have for a long time and mentally far brighter.
As a footnote, I shared this post on my Mastodon and a couple of people suggested that my experience may be due to my “taking control” or simply a placebo effect. Well, that is a possibility, of course. However, I’ve had symptoms for a long time that coincide with several mentioned on the documentation accompanying one of my medications and I feel that reversion to the mean/norm (basically, the placebo effect) was so sudden and coincided with taking the supplement that there must have been a physical effect of doing so rather than my spontaneously recovering…but, again, anecdote is not evidence, either way. One cannot do double-blind, placebo-controlled studies on oneself.
As regulars to the Sciencebase site will know, I’ve been doing some ad hoc wilding of our garden for a few years now. Always hoping that blooming wildflowers would attract interesting invertebrates. There are therefore patches and pots that I’ve not managed with all sorts of odd things sprouting from them at different times of year. At the moment, there is a big tub, which used to be crocuses and daffodils that has a very tall and leafy plant growing in it at the moment, with pale-purple flowers in bloom (it’s November!).
Apple of Peru, usually only has one or two blossoms at a time
I used the ObsIdentify app to take a couple of photos and it turns out to Apple of Peru, Nicandra physalodes. The species is also known as the shoo-fly plant (it repels aphids and other flies and although toxic is sometimes rubbed on the skin as an insect repellant. It’s also known as the Apple of Sodom, presumably somehow that relates to its encapsulated poisonous fruit.
Apple of Peru blossom
As the name would suggest, Apple of Peru is a native to South America, self-seeds easily, and is sometimes grown as a decorative annual. I didn’t plant it, seeds from some outside source presumably landed in the tub and it’s grown where it fell. I think it’s meant to be in bloom from April to July, usually in tropical and sub-tropical climes rather than the temperate zone, so not entirely sure what it’s doing with open blossom now and setting fruit in the middle of November in England.
TL:DR – The world population is now well over eight billion, 8 000 000 000
At the time of writing, the human population is roughly 7,986,585,500 as of today. That’s about 13 million shy of 8 billion people. On average this year population has been growing at about 222,000 people every day.
The world’s population has doubled since 1974, the year ABBA won the Eurovision Song Contest with their song Waterloo.
It was half the 1974 number in 1927, the year of the first transatlantic phone service.
We numbered a mere billion in 1804 the year Napoleon Bonaparte was proclaimed Emperor of France.
It had taken from 1600 to Napolean’s time for the estimated world population to have doubled to a billion, that was the year England’s King Charles I was born.
The population hit just 250,000,000 between the years 900 and 1000.
It was half that last figure some time between 200 and 500 BCE.
During the fourth millennium BCE, the world population was roughly that of modern-day Belgium where we find the municipality of Waterloo.
Projections suggest that the global population will continue to grow, but at a slower rate than in the past partly because of declining fertility. The United Nations projects that the global population will reach 9.7 billion by 2050 and 10.9 billion by 2100. However, these projections are highly uncertain and depend on a variety of factors, including fertility rates and mortality rates.
Fellow mothers, those who light up in the hope of seeing interesting nocturnal Lepidoptera will know only too well the feeling of disappointment when they check their trap the morning after the night before only to find not a single scaly-winged friend within. A BLANK.
Last night was wet and chilly, early evening it had been dry, cloudless, and chilly, with a bright moon. The local primary school also did their annual fireworks extravaganza. None of this had any bearing on the moths, they just weren’t flying into the trap. So, my first BLANK since last winter. Null results are, of course, scientifically just as important as hits. It is logged in my spreadsheet and will be seen by our County Moth Recorder, Bill Mansfield, in due course.
Meanwhile, here’s a photo of the beautiful and enormous Blue Underwing, better known as the incomparable moth from Cliveden House, the Clifden Nonpareil. Came to my garden in September 2020.
#TeamMoth #MothsMatter
ChatGPT words about mothing:
Moth trapping is a technique used by lepidopterists to collect and study moth species for scientific research. The most common method of moth trapping is the use of a light trap. A light trap is a device that uses a light source, usually a bulb or LED, to attract moths at night. Moths are attracted to the light and fly towards it, eventually getting trapped in the trap. Other techniques include pheromone traps, which can be used to attract day-flying moths. Also sugaring, which involves pasting a strong-smelling sugary, often alcoholic, mixture on to outdoor surfaces to attract moths that less interested in light sources.
Here are some tips for effective moth trapping:
Choose a good location: Moth trapping is most effective in areas where there is little to no light pollution. The trap should be placed in a location where it is easily accessible but away from human traffic.
Use the right equipment: A light trap should have a bright light source that emits light in a specific range of wavelengths. The trap should also have a funnel or cone-shaped entrance that leads to a holding chamber or container.
Check the trap regularly: Moth trapping should be done at night and the trap should be checked regularly to avoid overheating or overcrowding of the moths.
Why do moth-ers sometimes have blanks?
Weather conditions: Moths are more active in warm and humid conditions. If the weather is too cold or dry, the number of moths that are active and visible may be reduced.
Moonlight: Moths are known to be attracted to light, but they are more attracted to artificial light than natural light. If the moon is bright, moths may be less attracted to the light trap.
Migration: Some species of moths are migratory and may not be present in a particular area during certain times of the year.
Habitat destruction: If the habitat where the trap is located has been destroyed or altered, there may be fewer moths in the area.
I’ve waited patiently for one particular species of moth to turn up in the garden and the night before Halloween 2022, it made its inaugural appearance, drawn to a 15-watt fluorescent, ultraviolet lamp – the December Moth. Poecilocampa populi (Linnaeus, 1758). If the name seems anachronistic don’t blame me. The Lepidoptera textbooks tell you it can make an appearance any time between October and January, peak is mid-November.
Male December Moth
When I first started mothing back in late July 2018, I hinted to one of the very experienced enthusiasts I know, a guy called Leonard Cooper, that I’d probably switch off the lamp and put the trap away for the winter. His retort was one of shock and awe, “What, and miss the December Moths!?!?”. So I didn’t and I kept lighting up almost all the way up to Christmas. That year and for the three subsequent seasons I didn’t see a December Moth. I did see a few November Moths, however. They are a very different affair.
Where the December Moth is a chunky and fluffy, lasiocampid*, type moth, with a strand of what Mrs Sciencebase referred to as Christmas lights on its wings, the November is a grey geometer moth. In fact, the November is not really a single moth, there are several species that are superficially identical – November, Pale November, Autumnal Moth, and Small Autumnal Moth. Unless you examine their DNA, raise them from larvae, or examine the males’ genitalia, you cannot know for sure which of the three you are looking at and they are generally recorded as November agg, or more properly Epirrita sp.
Anyway, I am glad I took heed of Leonard’s lament and also pleased that my lighting up into the winter was also useful to another moth expert, our County Moth Recorder (CMR) Bill Mansfield, who urged me to continue logging Lepidoptera at least periodically through the winters for the scientific benefits. Moths are a very useful indicator of ecological health and so monitoring their diversity and numbers is useful not only because #MothsMatter but for the wider world of biology so that we can understand how climate change, habitat loss, and other factors are affecting the world around us.
Merveille du Jour
The larvae of December Moths feed on birch, oak, elm, lime, and, indeed, most species of deciduous tree. There is certainly a handful of oak and lime not too far from our garden, so the arrival of a December Moth, at long last, was not to be unexpected. The arrival felt likely as the moth is widespread in the UK and especially as another oak eater, the green and black & white moth with the formidable name Merveille du Jour had turned up in previous years.
Female Oak Eggar
The Lasiocampidae are known in the vernacular as eggar moths because of the relatively large size of the eggs laid by the female. Others in the group include the Oak Eggar, Grass Eggar, Fox Moth, The Lappet, The Drinker, and The Lackey.
My friend Andy, who, like myself, is a keen amateur wildlife photographer, often asks me questions about the birds and butterflies he photographs. I can usually come up with an answer. But, today, we were talking about Little Owls and he casually referred to the species as the Small Owl. As far as I know, there is no species known as the Small Owl. I pointed this out and he came back with an intriguing question. Why are the birds “Little” but the butterflies “Small”?
The Little Owl species does not have a counterpart Large Owl
For example, among the birds, we have Little Owl, Little Gull, Little Stint, Little Ringed Plover, Little Egret, Little Auk, Little Grebe, Little Tern. But, for the butterflies, we have Small Blue, Small Tortoiseshell, Small Skipper, Small Heath, Small Copper, Small Pearl-bordered Fritillary, Small White.
The Large Skipper has a Small Skipper counterpart
It’s puzzling…there is a subtle difference in our perception of what we mean by “little” and “small”, but it’s hard to define. Small is the opposite of big, little is the opposite of large. The Oxford English Dictionary suggests that while little is generally synonymous with small, it can have emotional implications associated with it that the word small does not, I can’t quite put my finger on what those differences are. When we discuss dwarfism, people with that condition are often referred to as “little people” but “not small people”…
Etymologically, the word small, a word of Germanic origin, means “thin, slender, narrow, fine” but also refers to a diminutive animal. Indeed, the true root in proto-Indo-European (PIE) is the prefix (s)melo- used to talk of a “smaller animal”. Little, etymologically speaking, is also Germanic in origin, the PIE root is “leud” meaning small.
So, back to Andy’s question why are the birds “little” but the butterflies “small”? I wondered whether it had something to do with the etymology of the words or perhaps whether the naming happened at different times and one descriptor was favoured for some reason at a given time.
Another possible explanation is that the use of small for the butterflies was done because there is a large counterpart. For the Small Tortoiseshell, there is a bigger but similar species the Large Tortoiseshell. Similarly, for the Small Skipper, there is a Large Skipper. However, there are no pairings among the birds, there are lots of different species of gull, but there is no Big Gull nor Large Gull to be a counterpart to the Little Gull, the same with the Little Owl, we do not have a Big Owl or a Large Owl species.
Often these kinds of differences are related to Anglo-Saxon versus Norman etymology, as in the peasants grow the pigs, cattle, and sheep, while the Norman aristocrats eat the pork (porc), beef (boeuf), and mutton (moutton). Stephen Moss just reminded me that he alludes to this in his excellent book Mrs Moreau’s Warbler: How Birds Got Their Names. “I noted that three groups of birds have Norman French names – ducks and gamebirds, which were eaten by French aristocrats, and raptors, which were used to hunt them. Same principle as farm animals and meat!”
Then there are the Great birds…
Great White Egret, Great Tit, Great Shearwater, Great Black-backed Gull, Great Crested Grebe, Great Grey Shrike, Great Northern Diver, Great Crane. The “Great” also essentially means big and there are “lesser” birds that are generally smaller than the common species: Lesser Redpoll, Lesser Whitethroat, Lesser Black-backed Gull, Lesser Spotted Woodpecker…
Moss also points out that in the US there are birds with “least” in their names ‘Least Grebe’, ‘Least Sandpiper’, and ‘Least Bittern’, for instance, we don’t have “least” birds in UK English…which maybe a throwback to US English etymology and the great divide between English and American.
“I have never really thought about why birds are great/little/lesser but butterflies are small/large, and I don’t really have an explanation. I suppose traditions in naming spring up early, and that namers therefore tend to follow an established formula. Some of the small/large butterfly names are 18th century or even, with Small Heath, late 17th century, so it might reflect usage at the time – Georgian vs Victorian? Simple English vs 19th Century elaboration?”
Marren points out that there are a few ‘little’ moths eg the Little Thorn – named later, perhaps. But again more usually large/small. He adds that “Great’ just seems the wrong word for a British butterfly or moth, somehow, but not sure I could explain why. ’Large’ is often (usually?) used where there is also a ‘small’, eg Large and Small White, Large and Small Blue, Large and Small Tortoiseshell. But I guess the same pairing is true of birds.”
A pub conversation with a retired friend who was an English teacher, had me saying “All creatures great and small”, which is almost a crossover usage…the hymn should perhaps be “All creatures great and lesser” or “All creatures large and small” but neither would sound quite so poetic as the original hymnal words by Cecil Frances Alexander.
A few days ago I tweeted about a famous picture of a moth, the Death’s Head Hawk-moth used in the artwork surrounding the 1991 psychological thriller “The Silence of the Lambs”. At first glance, the moth looks genuine, but closer inspection reveals that what is thought of as markings resembling a skull on the moth’s thorax is, in the movie illustration, actually an imprint of a well-known 1951 creation of Salvador Dali and photographer Philippe Halsman.
In that image, In Voluptas Mors, a group of naked women were posed in such a way as to create the illusion of a skull. Of course, this morbid allusion fits perfectly with the theme of a murderer who skins his female victims in the movie. The women are lambs to the slaughter, their fleeces flayed from their bodies by the serial killer and a symbolic moth placed on their tongues to silence them forever.
Although a representation of the Death’s Head Hawk-moth (Acherontia atropos) features in the promotional materials for the film. Fellow science writer Rowan Hooper reminded me that in the movie itself, it is the pupae of a different moth, the Carolina Sphinx Moth (also known as the Tobacco Hawk-moth (Manduca sexta) that feature in the plot. In our chat, I mentioned that I wasn’t particularly interested in moths when that movie was first on release, but he said he was very much interested in Lepidoptera (moths and butterflies) at the time, Indeed, Hooper was specifically working in research trying to figure out something rather odd about Lepidoptera.
It turns out that the males of all Lepidoptera, all 180,000 species of moths and butterflies produce two types of sperm. They make sperm that carry their genetic material, their DNA, in the sperm’s nucleus, so-called eupyrene sperm, but they also make sperm that lack that DNA, apyrene sperm, or parasperm. Indeed, at least half of the sperm are blanks. In one type of swallowtail butterfly, 90 percent of the male’s sperm lack DNA. That percentage is 96 in Manduca sexta. Even more bizarrely, Lepidoptera are the only creatures that do this.
Obviously, the fusion of sperm with egg is fundamentally all about fusing the genetic material from the male with that of the female to fertilise the egg and create offspring from both parents. So, why would males make sperm that contain no genes to pass on and more to the point would be incapable of fertilising the female’s eggs. To cut to the money shot: nobody knows, for sure.
There are hypotheses, of course. It might be that the blank sperm act as some kind of useful filler, inactive biological padding. The blanks perhaps take up the female’s resources somehow while the active sperm do their job. Maybe this precluded further matings with other males ensuring that the first male’s active sperm are the ones that fertilise her eggs. Alternatively, perhaps Lepidoptera females have defences within their reproductive tract to ensure that only the fittest sperm reach their eggs and so the males produce these blanks as decoys (after all blanks would require fewer material resources and energy to produce, if many are going to be wasted). An alternative theory might be that the blank sperm are some kind of nuptial gift for the female, not so much inactive filler as nutrients.
There is evidence that a gene known as Sex-lethal (Sxl) is involved in the production of apyrene sperm in Lepidoptera. A paper in PNAS looked at the activity of this gene in the Silk Moth, Bombyx mori, and found that it was partially responsible for the generation of apyrene sperm. Moreover, the team showed that apyrene sperm have to be present in the male moth’s ejaculate to allow the active eupyrne sperm to travel from the female’s genital opening, the bursa copulatrix, to her spermatheca (where she stores sperm prior to egg fertilisation).
So, while no definitive answer is known for all Lepidoptera that produce eupyrene and apyrene sperm, for the Silk Moth at least it seems that firing blanks is the best way for the active sperm to hit the target.
