BUG HOTEL – Cocoon harvest

The bug hotel opened in the spring of 2017, offering superior accommodation and personalized services in eight spacious yet cozy 9mm by 90mm holes drilled in healthy, un-treated, pinewood that’s easy to chew through should guests wish to make modifications to the otherwise comfortable cylinders.

The particularity of this property is that one of the outer walls has been replaced by crystal-clear 6mm glass that offers spectacular views. Privacy is ensured by a hinged flap that swiftly closes when so desired.

The official designation of the property is CB-890, because you can see the bee in all 8 rooms that measure 90mm in length.

It lies just outside my window, by some flower pots next to the wall (SE) It was populated every year, starting in early spring, with the holes sealed by May. The highest number of holes occupied must have been 5 or 6. Last year (2021) was the lowest so far with only 3 taken.

The tenants are solitary bees of various species, and there are, of course, various parasites that treacherously prey on their larvae.

This pretty cigar-looking structure is made by the leaf-cutter bee:

These are made by what I believe to be mason bees:

A whole row of cocoons has been killed by the larvae of the Carpet Beetle. They manage to break the cocoon, get inside and feed on the larva.

The life cycle is as follows: there is frenetic activity in early spring, when females find (or make) a hole in a vertical structure, usually wood, and fill it up with several mounds of pollen. The bee then lays an egg on each mound, separates them with little walls of mud and seals the entrance. The egg becomes a larva that feeds on the pollen and builds a cocoon in which the bee eventually develops. The following spring it chews through the cocoon, breaks the mud wall and flies out.

Females are about half the size of males and the smaller cocoons are always closest to the entrance, as females hatch first. The larger cocoons are the males that hatch last. A dead female near the front can mean the dearth of all cocoons, as sometimes the newly hatched bee does not have the strength to chew through several separations.


Sunspots AR2936, AR2937 and friends, the first being amongst the largest of young solar cycle 25 and which hurled a coronal mass ejection towards Earth in the early hours of January 30th, bound to reach us February 1st or 2nd.

AR2936 has multiple dark cores larger than Earth, and the entire group stretches more than 100,000 km across the surface of the sun. That’s about 8 Earths one next to each other, or a little less than a quarter of the way to the Moon (which is 30 earths away, roughly).

Beautiful footage from SOHO showing the CME that is expected spark auroras at mid-Northern latitudes:

MICROSCOPY- The Swamp III / one year

One year on, and there is an abundance of life in the jar, both macro and microscopic. Vegetation is now mostly on the bottom, and it largely consists of algae. More algae at and above the water line, on the walls of the jar. The lights have been on for the most part of the last 6 months, with maybe 48h of darkness in total. Temperature has been a steady and warm 22-24°C.

A superficial visual inspection with the unaided eye shows much activity, with a plaetoria of ostracods happily swimming around looking like they own the Swamp (they totally do). Intelligently estimating their number is an interesting exercise for which I am too lazy right now, but a quick guess would be several hundred of the larger specimens (0.5mm+) and thousands of the smaller ones.

This was filmed with a phone through the wall of the jar and I may have cropped:

Much activity visible with the naked eye – ostracods everywhere

This is a 1.5cm piece of wood at the bottom of the jar. Footage is from above, through the hole for collecting samples:

Ostracods on a 1.5cm piece of wood

The algae colonised the walls of the jar to the point of becoming quite opaque at one point, but then died and peeled off after about 9 months. The walls are now very clean (below the water line).

The most abundant micro-organism is a species of ostracod. This is a fresh water crustacean that lives inside a clam-like structure composed of two valves articulated on the dorsal side that swims around by agitating its antennae and claw-like appendages. Judging by their numbers, the Swamp contains no predators for this creature.

They move about quite rapidly and seem to rely entirely on touch. I saw no interaction between individuals apart from the occasional bump.

They are small enough to become transparent when backlit so internal structure becomes apparent quite easily:

The outside of the shell seems to be covered in what looks like fine hairs:

A different perspective at lower magnification:

And a close-up of its lovely face:

Now this is the interesting bit. I found this pair of paramecia that was twirling around in the same place, not moving about like their friends, and that seemed to be tied together in some way:

Paramecia have largely come to dominate the micro-organisms in the jar, their numbers now far exceeding rotifers, of which I only saw one:

Nematode worms continue to live in the substrate and range from very large ones (cm) to smaller, more agitated specimens. I cannot say whether there is one species of more.

The only rotifer I found. It was not feeding and I only saw it moving about. They used to be the dominant kind of micro-organism for the first 6 months or so.

This is a bug that I see for the first time. It’s large, about the size of the bigger ostracods (1mm) and there seem to be quite a few of them.


As the lightbulb regularly needs replacing I decided to stick it in a wine cork and allow for replacement without unsealing the main cover of the jar.

This came after my first attempt to change the lightbulb without unsealing resulted in catastrophic failure, as can be seen in the photo showing the lightbulb on the bottom of the jar.

The Swamp III is not a closed system, strictly speaking. I am not 100% sure the cork top is perfectly sealed to the glass of the jar and I have completely removed the top three or four times. I also made a hole for collecting samples that I open every time I do so. I have also added several mm3 of starch sometime in early winter. I give it non-stop light and temperature is steady at 22-24°C in winter and 24-30°C in summer.

This being said, it does its own thing in there and provides for excellent observation material. A great little toy.

This is an example of a sample that I collected, with some water, stuff from the side of the walls, from the surface of the water, from the bottom and from the substrate.

The camera records afocally through the microscope

ASTROPHOTOGRAPHY – How to tell a planet from a star

Astronomers studying variable stars have compiled catalogues listing about 10’000 stars visible with the naked eye (Mag 6.5 and less). This includes both hemispheres, so an observer at mid-Northern latitudes would technically be able to see about 6’800 stars on any given night (this takes into account the Southern stars visible in the North). Out of those 6’800 dots that one can see, five of them are planets. So how to tell the difference?

Stars emit their own light, whereas planets reflect the light of the Sun. Stars are point sources of light, meaning they have no apparent diameter – no matter how high the magnification, it’s impossible to see the actual sphere that makes up the star. Planets are significantly closer and one can see their actual shape, be it small (arc-seconds of a degree). As a result, star light is more prone to distorsions from the atmosphere and this is why stars twinkle, whereas planets do not.

How to photograph the twinkling of stars:

Expose for 2-3s and gently tap on your camera to induce movement and get a line on the photo, rather than a dot. Light from planets will be monochrome (Mars is a good target, because it’s nice and red), whereas light from a star will pass through all the colours of the rainbow as it’s distorted by the atmosphere.

Mars shows a constant red colour whereas a star will vary both in intensity and colour.

OPTICS – Glory

A 20° Glory sporting several rings, indicating constant droplet size distribution on the cloudcover below. This particular Glory was centered on seat 9C, behind the left wing of the Avrojet 100 aircraft I was flying in – passengers seated more to the front saw the Glory centered on their position (the aircraft shadow would be more to the left).

Interesting to notice that as the plane descends for landing its shadow gets bigger but the glory diameter remains the same.

More info and the related math of this phenomenon here.

OPTICS – Drink for free with physics

So I’ll bet you a good Bordeaux I can make the arrows point different ways without touching them.

The physics:

The water in the glass creates a cylindrical shape that resembles a magnifying glass which flips the image on the vertical axis due to refraction: light converges somewhere in the middle of the glass and is projected – flipped – through the front.

More info and original video here.

ASTROPHOTOGRAPHY – The Sun / sunspots 2797, 2798 and 2799

Below, the small sunspots designated AR2797, AR2798 and AR2799. The latter has the particularity of being the first in the Northern hemisphere of the Sun for the last 2 months. This is a one-shot exposure of 1/3200s at ISO 100 on an APS-C CMOS sensor through a 85mm f/5.3 refractor (Takahashi FSQ85) with a visible light sun filter (transmission 0.01%).

The sun filter is a Mylar sheet (a form of dimensionally stable thin plastic) powdered (probably) with aluminium to block 99.99% of the light of the Sun and allow observation of sunspots.

MICROSCOPY – The Swamp III / six months

The Swamp III sample has been collected at the end of summer, in early September. Now, after having spent the winter months inside at a comfy 22-24°C (rather warm, really) I am happy to report there is still life inside the jar: both plants – well, algae to be more precise – and protozoa. Anything moving at this point is alive because it reproduced.

The LED lights that were initially installed eventually died, and were replaced after four months or so. The cap was re-sealed on this occasion (hot glue in between the cork and the sides of the jar, with electric tape on top). I kept the lights on for months at a time to make sure the algae were producing sufficient oxygen and food for the protozoa. After the lights went dim and then died I added a pinch of stark to compensate the loss of light and feed the creatures inside. For the last couple of months I switched the light pattern to the normal day / night alternance and significantly reduced its intensity (placed under a lamp rather than the LEDs inside).


The walls of the jar have became almost opaque with the algae growing on them. Some are long filaments that seem to be growing on the walls, in the body of water and above the water line. There is also a much smaller variety, that sticks to the walls and makes a fine, green film. The substrate is black mud and pebbles; it seems to be partially colonised by a lighter coloured algae-type organism. Will have to check in more detail.

There is no sight of the snail or the bubble bugs. There is no movement that can be seen with the unaided eye. Using a 25mm eyepiece for astrophotography as a loupe allowed me to see the larger protozoa swimming around the jar, so they managed to survive and reproduce. It would be interesting to know how many generations have spawned since I collected the sample.


I collected samples from the body of water, from the side of the walls and from the substrate. First inspection shows algae and protozoa – the jar is alive and I can now reasonably say that I have a self-sustaining ecosystem.

Rotifers are alive and well, they seem to feed happily and there are many of them. I could see different sizes, but there seems to be only one species (Bdelloids). They have really multiplied and are present in great numbers in any sample I take from the jar. It seems they reproduce asexually and all are females.

Rotifers after six months in the jar

More elusive but equally abundant paramecium. They are particularly active and move very fast through, and out of the field of view. here’s a calmer one:

Not many, but rather large nematode worms. I didn’t see them in all samples I collected from the jar but the ones I did manage to catch were huge (several cm) compared to the ones I saw in the beginning (max 1cm).

Large nematode worm

MICROSCOPY – The Swamp III / two months

The water is quite clear, as are most of the walls. There is one (barely) surviving plant and some green algae. The snail and the bubble bugs are still alive and happy. Saw a new, large insect cca 1cm.

I drilled a hole in the cork and installed an aluminium tube with an airtight screw-cap. I re-sealed the cork to the side of the jar with hot glue, then covered it with tape. The ecosystem is, for all intents and purposes, sealed, but allows access to take water and other samples.

I use a large-ish syringe on which i put a shrink tube and a plastic cylinder at the end to get the samples through the hole I put in the cork.

Most of the surviving plant life consists of algae. The one plant that seems to be alive has no more green leaves above the water line. The roots growing out of the stem do seem healthy and alive.

The algae are a deep shade of green and grow attached to the stick on the bottom of the jar, on the decaying leaves and on the side of the jar (above the water line).

I switched the light off for one night and there was a new bug floating upside down near the surface. It was still alive but obviously not ok.

There are more and more eggs, with obvious fresh ones appearing on the sides and on the bottom of the jar. Also new batches on the stick as well. The older ones seem to have been colonised by algae and have become green (picture on the left). The “nucleus” of the egg seems to be an elongated, twisted ribbon that looks pretty much like an intestine. It has not changed since the eggs have been laid. I still suspect the snail.

I found the large bug i mentioned before. It died. it’s big, and ugly, and am sure it could crawl out of the jar if it chose to do so. Seal your jars quickly.

Many nematode worms are visibile with the naked eye, about 1-2mm in length, swirling and jerking around the jar.

MICROSCOPY – The Swamp III / one month


There still is life in the jar; very few plants left. Water is surprisingly clear and the algae have all but disappeared from the walls. The twig has sunk well below the water level.

Only one plant seems to have survived. It’s a long thin blade of grass that produced a very nice root that eventually found the bottom. this seems to be surviving and has risen well beyond the surface – it’s flat against the top.

The snail is large 1cm+ and happily wondering around, as are the bubble bugs. Eggs on the stick underwater and on the side of the jar; I suspect the large snail laid them. The algae have all but disappeared from the sides, probably eaten by the snail, as I’ve seen it munch away at them several times. The water is surprisingly clear – I suspect there is not enough light for algae to develop in large numbers. I think the jar *cycled* in the aquarium sense of the term.

MICROSCOPY – The Swamp III / one week

The swamp is most insulting to the nostrils. Became blurry with algae both on the jar walls and within the mass of the water. Large 8-10mm larvae jerking around on the surface. Am expecting mosquitoes which will be killed.


Many, very small organisms quickly moving about. Larger ciliates twirling and swimming about.

A forest of what look like long, green algae but they move on their own, waving around as if in flowing water. I believe they may not be plants.

MICROSCOPY – The Swamp III / day five

Almost a week now, and am happy to report that there are many micro and macro organisms which seem to be well alive and colonising the swamp.

Not many snails, to my surprise. Saw one or two small ones, maybe 2-3mm. And a larger one, some 6-7mm, brownish. The air bubble beetles are fond of the branch (of which 5cm are sticking out) and walk about it underwater in a bubble of air that they somehow pick up from the surface. These creatures are just the right size (and mass and shape) to exploit surface tension.

Saw some flat worms, small, maybe 5mm, many nematodes twirling about. Some daphnia, but not a crowd. Cyclopes, as well. Many larvae, many dead. Saw what looked like a small 2-3mm fly or mosquito hatching from one on a leaf on the surface. All mosquitoes will be killed. I also saw what I believe are carnivorous oligochaete worms. Many ciliates.

The plants seem to be doing well, although there is much muck on their leaves. Saw some roots in the substrate and also fine strands of algae that seem to be colonising it. They are advancing upwards on the wall of the jar.

One very pretty sight are the bunches of Conochilus, that contract suddenly and then slowly open up again. I do believe they grew to about 2mm across, from 1mm yesterday. They seem to be attached to the wall of the jar, and there are many – several dozen.

The bunch of Conochilus


Recorded focally on an APS-C sensor through a 100x microscope

Saw what looked like ticks, several of them. They are on the underside of small, des leaves floating on the surface. Must really seal this jar.

And some spirogyra algae, lovely as usual:

MICROSCOPY – The Swamp III / day two

The water is somewhat clear, with much of the material previously in suspension fallen to the bottom.

Day two – 6.IX.2020


A few (5maybe 6) unidentified beetles cca 5mm long. One seems to have eggs on its belly. They bring bubbles of air underwater and stroll upside down on plants. They climb on top of each other (3 at a time) and relax on the bit of wood protruding from the surface of the water. Some lay motionless among the plants on the bottom.

A snail, possibly more:

Any what I believe to be mosquito larvae. This mens I have to seal the container and find a way to gas them.

The beetles carrying water bubbles underwater:

I saw nematodes, a considerably larger snail-looking creature, green snails, what looked like paramecia and the crustacean-looking things.



September 5th, 2020. Day one.

This is a closed ecosystem that has little to no exchanges with the outside environment. Collected September 5th, 2020 from a 20 year old fishing pond (ex-quarry).

The Swamp III -sealed jar with pond water, plants, decaying organic matter and a pebble substrate

Contains: cca 2,5l pond water. pebbles, water plants and cca 0.5l muck scraped off the bottom.

River pebbles and water plants

A selection of the water plants collected from the pond:

Water plants from the pond

LED lights shining at 370 lumen.

The light setup

Week 9

The jar has been placed outside now for 3 weeks. Weather is uncommonly warm and no rain. Water level dropped several times and was re-filled with bottles still water, tap water (pretty stupid, because it’s full of chlorine) and sparkling water. It never fell below 50% of the volume.

Photo jar week 9

A water sample was collected today from a freshwater flowing lake (particularly clean these days), together with a small clam, algae and muck scraped-off a semi-submerged rock.

Sample contains oligochaeta, nematodes

Week 6

Snails everywhere. I counted 30 just on the exterior wall of the jar. They range from under 1mm to about 6-7mm for the largest ones. They all seem to be of the same kind – the reddish, almost transparent ramshorn snail.

a bunch of Ramshorn snails

The plants – or plant, rather – is thriving, with many stems crawling out of the water on the jar walls and a small forest emerging above the water level in the center of the jar. The long thin spirogyra algae have filled almost all volume which is not already occupied by the water plant.

The water plant emerging from the swamp
The water plant crawling up the jar walls
The jar getting some UV on a sunny day in March

The cyclops are swimming about happily, have spotted females with egg-sacks. Surface tension makes it that a small pellicule of water crawls up the side of the jar – the volume cannot be more than a square mm, if that. I could see with the loupe nematodes, water fleas, snail eggs and many round, perfectly formed coleochaetales algae. I really have to find a way to take pictures through that lens. The magnification is just right, in between naked eye and microscope observation.

Week 5

Water level had dropped by cca 2cm so I topped it off with alkaline bottled water. The plants are well and alive, have seen nothing changing colour or otherwise rotting. Little bubbles of gas have formed in between the weeds, like marbles. Am wondering whether it’s oxygen.

One way to know would be to capture a reasonable volume and shine white light through it to see emission and absorption lines – but that would be significantly more involved than it sounds.

I can see no dead bodies of organisms on the surface, on the bottom or in between the weeds. The mosquitos I killed have disappeared.

Gas bubbles in the water plants

I dropped a crumb of bread in the water in an attempt to lure the snails so I could count them. It somewhat worked – there were snails feasting on it for a couple of days but no way to have them all there at the same time. The bread was broken down into a hazy mist which smaller organisms are probably eating now.

There are 3-4 large snails measuring now about 4mm. Many smaller ones ranging from <1mm to about 2mm. They are so small and light that they can actually slide about while upside down, using the surface tension on the water surface.

The water plant has now emerged and there are brown hairs growing out if the stem – i suspect it’s some form of root. They are only visible on the part of the plant which is not submerged. Maybe I should put a stick in the jar with part of it out of the water so things can crawl up on it.

Very happy to have seen a couple of water fleas, quite large and active. Cyclops are dashing around as usual (still no egg-bearing females).

One month

The Swamp II – one month / March 2020

An overview of the Swamp at the end of the 4th week.

This also marks about 5 months since I started the jar in the first half of October 2019. It originally contained water from a very large freshwater (flowing) lake and from an old quarry, now a fishing pond (about 20yo ecosystem), as well as some algae. It was kept outside October to January, then brought in at room temperature (cca 23 C) on February 10th and given about 400 lumens 24h a day.

In February water level was about halfway, at the 3cm mark; can still be seen on the side of the jar by the line of algae that grew where the water line used to be. I added bottled water up to the top of the jar (6cm mark). The water was clear, with very little algae and no visible living organisms. Microscope inspection showed rotifers and small cilliates.

The Swamp as it came out of hibernation
February, 2020

A week later I seeded the jar with fresh (collected in the second week of February 2020) samples from the fishing pond (slime, dirt, water plants, algae) and plans that grew in a fresh water source that I found on the side of a hill.

Removed the rotting tree moss
and added algae and water plants

I have been giving it light and keeping it warm ever since. This is the situation in the Swamp after one month.


There is one dominant macro species: some sort of water plant that seems to thrive without any soil. It has many parallel stems a couple of mm in circumference, each with leaves growing on all its length.

The water plant.
Growing happily and now rising above the surface
The large leaves provide a perfect surface for eggs
Good plant.

The most abundant of the algae is spirogyra, the very fine tubular algae with their spiral coil of chloroplasts that look like gelatinous mist in the water. I had also noticed segmented algae, somewhat thicker than spirogyra and without the coil, having neatly separated chambers filled with chloroplasts.


These algae are long tubes, incredibly fine and stick together like hair, making for some very fine curling locks, as can be seen below. It also tends to occupy all the volume it is allowed, especially when grown in a somewhat controlled environment like my jar.

A curl or Spirogyra cca 2cm long
The other kind of algae growing in the jar – segmented and with no spiral

Something interesting I found – what appear to be parasitic algae (maybe some form of symbiosis?) growing on the leaves of the water plant. The algae are tubular, straight with no ramifications and contain chloroplasts.

Parasitic algae growing on the leaves of the water plant

Microscope inspection shows the pretty Coleochaetales with its cells disposed in a spiral as well as the desmid Cosmarium. I also spotted Merismopedia, neatly arranged in rows.

the desmid Cosmarium

The plants produce significant levels of oxygen, seen in the little bubbles that form among the water plants and algae.

Hanging in between the water plants I found little dark spheres about 1mm in diameter that, upon inspection, revealed to be sacks full of strange algae (?) composed of spherical beads:

A sack of what looks like algae
A sphere of algae

Of the larger living things, must first be mentioned the snails, the largest sporting a whopping 5 or 6mm diameter shell. Many baby snails around, they seem to be reproducing abundently. I have seen a group of 7 hatching.

Snails hatching
I believe this to be the same egg sack at an earlier stage of development

I’ve seen a few Oligochaeta, rather large in size (up to 5mm) and some larvae that looked somewhat similar to them and were of comparable size.

Water fleas have been a pleasant surprise – only noticed them a few days ago. Small and with an almost transparent shell, they move somewhat slower than the cyclopes, which are abundant and slightly larger in size, at about 1mm.

Cyclopes (cca 1mm)

One morning I found mosquitos and their larvae, but I quickly gassed and disposed of them (6 or 7 mosquitos, about 5 larvae). Pretty colours, yellow with black dots.

A mosquito that hatched in my jar
Eggs (?) on the dead mosquito’s wing after a few hours in the Swamp

Nematode worms of different sizes are also present, from the smaller, more agitated ones, to the larger, slower ones.

Still in the macro realm, I found an escape-pod from a colony of Bryozoa: it’s a fortified egg that survives dessiccation, travel and all sorts of rough environments. I am insulted.

A Bryozoa statoblast – armored escape pod
Bryozoa ststoblast

There are – and have been throughout the winter – cilliates and rotifers.

A very small cilliate

It is virtually impossible to collect the same sample again if one wishes to observe its evolution. As such I decided to place two cover glasses in the jar – one is (still) on the surface, and one is submerged. I am hoping to monitor the deposits that will form. Maybe I’ll try coating them with different nutrients to see how things develop on them.

Cover glass placed in the jar to collect deposits

Week three

Macro organisms have developed in high numbers. I now have a hefty population of Cyclops of all sizes. Have not yet seen egg-bearing females with the distinctive sacks next to their tail but I am sure they will appear.

Catching this guy in the pipette and transferring him to a slide without losing, killing or otherwise maiming him was quite a challenge. Illumination is from above, so the eye would show nice and red.

The round organism below is Coleochaetales, and there appears to be an agglomeration of eggs (?) right above. On the left, a rotifer is stuck next to an air bubble.

Upon inspecting the algae in the jar I noticed a slimy blob attached to a stem, of a slightly darker colour and clearly not part of the plant. It was a bunch of fully formed snails still in the membrane of where the eggs developed.

So here are some snails hatching:

And something unexpected – a travelling wave of bacteria (?). Rotifers and other cilliates happily feasted on them.

I have to find a way to re-visit the same sample. For example the eggs below will probably hatch – if they haven’t already – and I have no way of knowing what organism it was.

Week two

It’s been about a week since I brought goodies to the swamp jar and – behold – there is much activity. Macro at that, too – quite a few creatures can be seen with the naked eye: some segmented worms, the snails I had previously seen, cyclops (happy they’re here – I like these guys with their bright red spot) and what I suspect are mosquito larvae that seem to have hatched recently and are jerking around just below the surface. At least three fully grown mosquitoes are flying around in the jar. These I don’t like.

Large worm found at the surface after having switched the lights off for 8h

To my great surprise I found some mosquitoes and these I believe are the larvae hatching:

I started giving the jar non stop light about a couple of weeks ago – not particularly bright (470 lm), but constant. The idea is for the plants to properly oxygenate the water and sustain the living organisms. I switched it off for about 8h during the night thinking maybe some things only happen when it’s dark and I found many many worms on the surface, I think gasping for air. The snails were on the surface as well so I assume the plants and algae consumed most of the oxygen while the light was switched off. The sealed jar I had started last year died this way – three days by the window instead of under a lamp. I may switch off the light at some point again, but waiting for warmer temperatures and more sun during the day – it shall sleep outside because I don’t want *anything* crawling out of the jar and into the house.

I need to remove the mosquitoes so I can open the jar again. I’m thinking of knocking them out with smoke.

They were knocked out in less than 15s. Started to come to, somewhat, after about half an hour or so but I believe the damage may have been irreversible. Now they’re snail food, and that is very well.

Left, middle: larva and adult at 40x
Right: sample with scale in mm

In addition to the water plants and the two types of algae I had observed earlier I was pleased to find microscopic algae of different shapes:

And the long, pretty algae with the spiral chloroplasts:

Long, tubular algae with spiral chloroplasts

Catching a cyclope in a pipette is not the easiest thing, but great success was had, and here he is stuck under a cover glass for your inspecting pleasure.

And another sample of particularly photogenic algae:

Week One

Following a trip to the lake in which i usually go fishing, i came back with goodies to add to the jar. Scraped some muck off submerged stones, as well as from a dead branch. Also collected a sample of green algae developing about half a meter underwater close to the shore.

The Swamp II after 4 months, initial sample
This picture was taken the evening when i first brought the jar inside and started giving it light. The water is clear, no particles in suspension, very little algae confined to the old water line on the inside of the jar walls.
The Swamp II – after the first add-on
Water is no longer clear: 24°C and 24h light triggered algae bloom

As the jar is already full, I only took a very small water sample, maybe 10ml or so, with very fine gravel (.5cm3). The lake is an old stone quarry, abandoned 20 years ago and transformed in a bird reserve / fishing pond. It’s close to a rather large river that runs nearby and I imagine there are exchanges between the two bodies of water, maybe via underground waters. I am led to believe this because they release trout in it, which needs high levels of oxygen, usually insufficient in stale pond water full of algae.

This green moss-looking plant was emerging from the brown dead grass on the shore, so I took a handful with the aim of increasing the oxygen production in my jar swamp. Not sure this will survive given the fact that it’s fully submerged and has little to no soil. In the worst case it will decay and provide nutrients..

Moss-like plants that grow on the shore

Riding back there I found a fresh water source on the side of a hill – collected some soil and some of those undulating water plants that move suavely with the flow. After closer inspection I saw a plastic tube that was channeling the stream – I just hope it’s not pesticide-infested irrigation water as there are some vineyards on the surrounding hill sides.

Water plants from a fresh water source – I am hoping they will provide the required oxygen for all my creatures living in the jar

Given the little space I have available, I decided to remove the tree moss that was rotting in the jar. The mass of long, thin algae was particularly difficult to separate from it, but I managed to conserve most of it. I also left some moss, as when I first collected it I had found a water bear, which are undoubtedly among the coolest creatures alive.

While transferring all of the above to the jar, I took samples for closer inspection – algae, moss, soil, water and some of that decomposing muck I had scraped off the bottom. Living things were clearly visible to the naked eye and I made sure to suck up some of them in my pipette. An earthworm (would have been perfect for fishing – next time I know where to look for them) was among the moss so i mercifully put him in one of my flower pots outside.

One remarkable thing that I found was a 5mm gelatinous blob that has the consistency of snot (almost wiped it off first I saw it).

The Eggs

This turned out to be an egg-sack containing a dozen or so eggs, which are very much alive. 400x magnification shows the embryo being composed of several cells, tightly stuck together to form a slow-moving sphere.

8x speed

Normal speed

I’ve carefully placed it back in the jar and marked the spot so that I can remove it for future observations. Bets are open as to what will hatch.

In the small sample of water I collected from the pond there were two very agitated creatures, a few millimeters long, that i first mistook for nematode worms. I had inadvertently trapped one under the slide glass, so it did not move at all and could thus inspect the digestive system.


Inspecting the deposits on the walls of the jar I found yet another sack of eggs, significantly smaller and with only a few eggs inside. Looks flat.

Eggs inside a membrane stuck on the inside of the jar walls.
Probably snail eggs.

Day one

Meet Two of Three – the 2mm red snail with three loops. He feeds on the algae that grow on the inside of the jar. He also eats rotifers.

He could have been there all along, hiding in the moss, but only noticed him today. I may have spotted another, but am not sure. This snail is the only organism large enough to be seen with the unaided eye.

Under the microscope I saw ciliates – rotifers to be more exact. The highest concentration is just below the water line, among the algae that grow on the inside of the the jar walls. The vast majority are well active, moving around or clinging to some invisible speck with their split foot. I saw some which were still in standby mode, tucked inside the shell, cautiously probing outside then quickly retreating again.

I also saw a different, smaller organisms – probably ciliates as well, with what looked like whiskers both in front and in the back. Two nematode worms, jerking around, about 1-2mm in length.

There are algae of at least two sorts: the circular, spot-like colonies where the initial water line was, and the long filaments with a really pretty spiral of chloroplasts. I could see no segments. These are light green and occupy most of the water volume.

The tree moss is brown and doesn’t seem alive. I’m, hoping there are spores and various cocoons inside to populate the ecosystem. I saw a water bear in that moss when i first collected it, so there is hope.

The jar is getting 24h light.