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Major survey finds worms are rare or absent in 20% of fields in England (fwi.co.uk)
242 points by kibwen 23 days ago | hide | past | web | favorite | 100 comments

Back when I was a kid, after a heavy downpour the roads would be crowded with earthworms. You really had to watch where you step to avoid stepping on one of those suckers. Fast forward today and I RARELY see a single worm out on the road after a similar downpour.

This reminds me of a passage in the book Sapiens, where the author muses that there may have been prehistoric tribes where grandparents told tales of when mammoths were so plentiful hunters would take them every month, and the grandchildren would smile and nod. The grandchildren would in turn grow up and tell their grandchildren that there were once beasts called mammoths, and these grandchildren too would smile and nod...

The shifting baselines problem comes up a lot; it related to fish catches

It's described more here - https://oceana.org/blog/daniel-pauly-and-george-monbiot-conv... and aptly illustrated here - https://oceana.org/sites/default/files/285468/catch_of_the_d...


Daniel Pauly is amazing. We hosted him for a conference here in NZ a few years ago. Such a mind!

What is your connection to shifting baselines and fishing policy? My father (former commercial fisherman) is part of a recreational fishing group arguing that the goal of fish policy should be abundance not short-term profit. http://legasea.co.nz

I don't have a strong connection to it, I just know that it's an apt illustration and we have photos for it - I doubt fishers today would turn away giant groupers. It's also discussed in a book I just read, Whittled Away, about Ireland's horrendous wildlife and fishery management (while pretty, virtually the whole island has been stripped of its wildlife to turn it in to livestock grazing). In short, there used to be a hell of a lot more fish, of different species, and the stocks we want to return to are levels from an already diminished time. Though it's got a lot to do with the EU's common fisheries policy, which was similarly awful, but has been improved somewhat since, with at least a ban on deep sea trawling.

Excellent article.

I especially like "We have to get rid of this notion that the past is a provider of anecdotes and the present is a provider of knowledge". This way of thinking is pervasive everywhere, including on HN. But we shouldn't be so quick to dismiss the accounts of our ancestors because they seem exagerated when we compare them to our experiences today.

Same happens with climate change. Obligatory apt XKCD:


This is interesting, thanks for the links, but.....

It isn't science its basically relying on peoples unreliable memory. Should I believe my uncle Bob, when he tells me he used to catch fish bigger than he was using a homemade hook, and some twine?

So at the moment I'm struggling with what this is. History? Probably. A tool for deciding public policy? Probably not.

I'm not denying the phenomena, just that as it stands theres a severe lack of facts in the linked articles.


"Dr. McClenachan used photographs taken between 1956 and 1985 to document the loss of the large trophy fish in the Florida Keys, and compared them with photographs that she took in 2007. She found a major shift in species composition across reef communities through time, with larger predatory fish being fished first, followed by a steep decline in the sizes and weights of fish caught more recently. Historically, catches were dominated by large sharks and goliath groupers, but today, the catches are almost exclusively small snappers. Interestingly, Dr. McClenachan found that the cost of fishing trips did not decrease, meaning customers paid approximately the same price for a ~20 kg trophy fish as they do for a ~2 kg trophy fish now, some 50 years later."

Thanks. I still have issues though.

We don't know how representative those picture were. The 1950s pictures have survived over a half century, they were taken at a time when photography was harder work than today. I could go fishing, photograph my meagre catch, and put it on instagram for the world to see easily.

Plus these seem to be tourist photos? Maybe its a symptom of (inexperienced) amateurs going to Florida Keys spending big bucks for the experience, whereas in the 50s it was actual fishermen going out to catch big fish, and the very best would take photos of their catch.

Again I'm not denying the phenomenon, just how much we can actually rely on it to tell us something useful. You can't from this array of photos definitively state that populations of x,y and z have dropped i%.

Isn't that conclusion 100% the wrong way round?

If it were so difficult for photos to survive half a century wouldn't it be hard to show catches tended to bigger? After all the ancient 1950s photos of large catches have been lost through not surviving such unimaginable eons. Sorry for the tone, but seriously, by 1950s photography was not the rare and specialist thing it was in the 1910s. Sure, it might be just the unrepresentative ones that survived into modernity, but...

With millions of photos being taken daily today, shouldn't it be trivial to find some examples of enormous catches among them? Yet we don't find them. Yeah, yeah, I know, absence of evidence is not evidence of absence.

Reports of 2m, 100kg cod are from history, today both size and catch has plummeted.

My point was more that today I have a phone in my pocket permanently, digital photos are free so ill take a picture of anything. In the 50s there were financial and convenience barriers to photography, however small.

Plus these photos have survived. My modern photo of an un notable thing probably wont survive, a picture of a notable thing probably will.

I find it´s best to make a mental note, and talk to Uncle´s friends. There is an intergenerational information transfer band if you pay enough attention to it. Plus your own memory will inform you after a while.

I remember growing up and there being 3-4 weeks of snow around January and putting on multiple pairs of socks to play in it. My mother remembers there being a couple of feet of snow up into March, and getting trapped once driving across Dartmoor.

Perhaps your children will ask you what snow was.

Agreed, but that isn't science.

You could use it as a prompt to start doing more research to see if there actually is less snow. I'm not sure what else you could do with that information though, a tool for raising awareness of climate change?

Photos are better, they're useful for things like measuring glacier retreat. But even in your example there would be issues, if snow becomes noteworthy more people will take photos of it, so already you can only be confident of looking at the most extreme examples.

Aren't there trading / sales logs, like, official records from back then?

You will also love this twitter thread: https://twitter.com/drmegafauna/status/1088716741700710401

Also did anyone notice that they don’t clean off insects off their car as often as before? Just 10 years ago, when I used to commute 170km every day in my car, I would have to clean the windshield regularly. I think I cleaned it once the last year and I even travel further today...

Yes, insects are also vastly reduced. In my region, there’s an increase in ticks (and tick-borne disease) because there are less insects, leading to less birds, leading to thriving ticks. So, an annoying side effect of reduced insect count is that we have lots of ticks in our gardens.

BTW we have non-organic agricultural fields in 50m distance of our house, so that _might_ be a factor for the dying insects.

Oh, and organic agriculture also uses pesticides. They just use different („natural“) ones.

You'd think there'd also be an uptick (ha!) in animals that eat ticks, but maybe that takes a lot longer to correct itself. If it wasn't for the prevalence of pesticides, insect populations would restore due to a shift in balance - that is, less insects = less predators eating them, less predators = more insects, etc.

I’m afraid a couple ticks per garden are not enough for any animal to survive..

The dramatic reduction in insects on car windscreens could be "explained away" by technological advances in car design (getting windscreens covered in insects could conceivably have been a problem great enough for someone to have invested time and money into resolving with more efficient aerodynamics of windscreens or whatever). Not saying that is actually the cause, just that many people could rationalise it as such.

The earthworms on a path or road is slightly more troubling though. Not something I'd thought about before, but there is a path through a park where I grew up that used to be covered in earthworms after every rain when I was a child, but the odd times I've been back up since in similar conditions I've not noticed any at all. Being a park it wouldn't have been exposed to more intensive farming or anything else. Same park, just a different time.

Chilling thought that there could be significant and detrimental changes underway in nature, happening on generational timescales so slowly that no-one notices, a little like the proverbial frog in boiling water.

> The dramatic reduction in insects on car windscreens could be "explained away" by technological advances in car design

I have been driving the same car for 20 years with the same roof-rack. 20 years ago the roof-rack was crusted with insects after each trip on the autobahn. I had to clean them off with a bucket of water and a sponge after each trip. I remember this because it was a standard routine. These days, when I come back from a trip, there is nothing. I haven't cleaned the rack for years.

With the introduction of LED lighting and lighting becoming cheaper with it, the amount of artificial light at night has increased over the last decades and may be contributing to declining insect populations as has been noted in the UK and Germany.

Same car? Could improved aerodynamics play a part?

I noticed the effect motorcycling. With an aerodynamically unchanged helmet and headlight, riding mainly naked bikes.

Last time I saw this crop up in a thread another comment claimed they actually were using the same car.

Maybe 50 years of these rivers of metal boxes reliably taking out trillions of insects yearly has played a part too.

I also observe less insects on my windshield, same car as 25 years ago.

Might be it.. Ford Mondeo back then and an Opel Meriva today.

You drive too far. That's insane.

Time wise though, it might be a faster commute than in Silicon Valley.

Around 1.5 hours today each direction, but I am commuting to a different country and have to cross a bridge.

Back then it was 1 hour or so - maybe a little less if traffic was good.

How can you waste that much of your life? You've spent almost an entire year over the past ten years just moving your body around because other people want you to.

This would be considered a long but not especially noteworthy commute in the US.

1.5 hours each way gets you into the “supercommuter” level but 1 hour each way is fairly common.

I did just over an hour each way for three months and questioned what the point was. I was wasting my life just so I could live in one place and work in another, but for what? My "living" basically consisted if eating and sleeping and my body started to become fat and unhealthy due to not having the time to exercise. What's the point of transporting a fat, useless body 100 miles every day?

Oh, I'm 100% onboard that one of the quickest ways to improve your life is to lower your commute time. I'm just saying commuting that long is not a particularly odd thing to do.

Being overweight is not a particularly odd thing either. It's not good, it's just mundane.

I guess you eradicated all insects along your commute route.

More seriously, my car is full of dead insects just from a few trips to the airport and I live in a metro area with almost 2 million people.

Possibly a factor. I think it's quite likely insect numbers are declining but some amout of the windscreen affect could be accounted for by good old Darwin - all those insects you scraped off your windscreen found their reproductive success curtailed with extreme prejudice.

Could the design of cars be the driving factor?

I think I noticed this too. When I was in elementary school in the early 2000s, the stench of run-over worms was almost unbearable after rains. Worm guts everywhere. There were also bugs flying around me whenever I went outside to play. I hated it and wanted it to go away.

It did.

Does it concern you? It does me.

Oh yeah. Be careful with what you wish for. One day us humans might not be just dominant, we will be alone. And in that sense, I don't want us to prevail against Mother Nature; I just want a healthy balance.

Mother Nature has been around for a very long time. She will not remember us when we are gone.

> Mother Nature (...) will not remember us when we are gone.

She will. Yes, she will outlive us, but with very heavy losses. Due to these losses, it will be very obvious we have existed:


"one of the most significant extinction events in the history of the Earth" ... "is mainly a result of human activity."

"The current rate of extinction of species is estimated at 100 to 1,000 times higher than natural background rates."

And we "just started" (considering the known effects of the human induced global warming).

I think you missed the point of the comment. If human beings drive ourselves extinct, life will eventually rebound just as it has from other, even larger mass extinctions.

What the comment actually claimed is that whatever will be after us "will not remember us."

Which is not true. Other comparable extinctions to the one we are currently causing are on the hundreds of the millions of years scale.

What we are causing will be definitely seen as an extinction event for at least millions of years in the future. That's how big it is. "The life will eventually rebound" is completely different from it "will not remember us."

Mother Nature won’t remember us. Mother Nature is a non conscious evolutionary process. The non-human conscious entities within it lack the means to carry on cultural memory of the hairless primates that once ravaged their world. That doesn’t mean there won’t be a record of us though.. any future evolved tool-wielding intelligence would certainly be able to infer our presence.

> Mother Nature is a non conscious evolutionary process.

Of course, and it's completely obvious that I never claimed human consciousness of the whole nature (you can read elsewhere my view of consciousness, hint: it's not given by deities). The answer is not even a response to what I actually wrote.

i hate when this sentiment pops up. it is practically meaningless but can even be even be viewed as harmful. most people don’t care about the environment already, so stating it will live on just silently emboldens people to keep on keeping on. many plants and animals are already dead directly due to human influence and others are to quickly follow.

She does not have that much time and thus tries at intelligent life left. Gradual brightening of the sun will start making the earth uninhabitable in about 800Ma due to accelerated silicate weathering.

Can you provide some links with more details? Googling sub-phrases from your comment finds me nothing but information on the natural weathering cycle of silicates as it relates to CO2.

I still see tons of worms in the US. It’s been raining like crazy in Georgia and I’ve had to dodge a few worms. During the summer my driveway is a worm death trap. I do a lot of gardening in pots and worms always find their way inside.

I noticed some worms this past fall after a downpour, it was just a few and it gave me pause. I do recall as well when I was a kid (30ish years ago) that there were a lot more worms. But I lived in the suburbs then, now I'm in the city, but near a large lake and large wooded area.

Are these the same roads?

If you moved from a farm to Manhattan, we need to talk about the setup of this study :)

They moved here, to our farm in Sweden. I just finished cutting and splitting a dead and partly rotten tree. The core of that tree was filled with a good approximation of soil which again was filled with earthworms. They were also slithering between the bark and the trunk in droves - this tree being partly rotten the bark was loose on the trunk - as if they were getting ready to evolve into treeworms.

When it rains it is crawling with the things. Living in the forest and having an unpaved lot probably helps here.

My driveway gets covered with them.

They love cooking on that black top.

Now that you mention this, I've noticed it too. It's getting rarer and rarer to see them on the roads and driveways after a rain.

Where were you a kid?

When were you a kid?

Late 80's into 90's.

How were you a kid?

Most people start out that way.

big if true

In the US, invasive worms are converting forests from fungal decomposition regimes to bacterial decomposition regimes.

Not a great development for mushroom foragers.


Fun stuff.

The last glacial maximum in the US pushed all of the earthworms out of the north central US and Canada, and if memory serves the 'Northern Hardwood Forests' exist in a subset of that area?

Earthworms of pretty much any kind are invasive there, and it's not just a soil microbiome problem, it also affects seed germination. Some of those tree species are adapted to germinate in a bed of leaf litter.

It's a challenge. People post things online that are appropriate to their region and beginners elsewhere don't get why they might not work locally (like that some plants are useful in zone 8 but invasive in zone 5, or vice versa).

> Not all foreign earthworms are destructive. Of the 5,000 species around the globe, only about 16 of the European and Asian varieties do the real damage. One of them is the night crawler (Lumbricus terrestris), a popular fish bait that can measure up to 15 to 20 centimeters (six to eight inches). Another is the Alabama jumper (Amynthas agrestis)—also known as the snake worm or crazy worm—an aggressive Asian worm that lives at high densities and can literally jump off the ground or out of a bait can, according to fishing lore.

So maybe we should use some of the remaining 4984 species of worms as fish bait?

Red wigglers are also useful for both purposes, and because they don't burrow they have trouble overwintering.

It's not perfect, but they are held to be a lesser of evils.

Sure. It's pretty much too late though.

Probably a result of tiling the soil. Disturbing the natural ecosystem of it. And pesticides too presumably.

Something like permaculture could help. Chop and drop. Mulching on the spot.

True only if tilling has increased recently. The question is, what has changed since the last time the dead fields had earthworms? That's the cause. Reversing or neutralizing that change is the cure.

Let's figure out how to fix this the right way, and now, before the remaining fields die off too.

I don't know the numbers for the UK but here [1] are some numbers for Bavaria with worm counts from a lot of monitoring spots starting in the 80s. (sorry, slides are in German)

In the conclusion the author says a connection to the tilling method is likely. (worm numbers in Bavaria actually have increased as more and more farmers have changed away from "full" tilling).

[1] https://www.lfu.bayern.de/boden/bodendauerbeobachtung/fachta...

Sorry, I should probably add that the worm number also very heavily depends on the kind of ground you have on your fields. In case that is not apparent from the slides ;-)

It's not clear that this is a recent phenom. It's a result of voluntary samples, that cant be compared to a previous situation. It may be useful if they repeat the measurements in the same places, but currently it's more like an internet pool.

It is possible that population decreases gradually over many years, rather than in a short time frame.

I can't find the studies now as I should be working, but there's lots of evidence to say poly-culture is also very necessary for a healthy soil biome.

I was out digging in my field yesterday (in Ireland, not England) and thought it was interesting that there was a large variance in worm counts. Some areas had massive numbers of worms pushing 20cm, and others had relatively few, smaller ones. The bigger worms were in areas that hadn't been grazed by sheep, but I'm not sure how that relates, if at all (the sheep have been gone for a few years).

That may be about soil composition, but yes, many/most earth worms are detrivores, so the more to clean up the happier they are.

Also sampling bias.

Speaking of Ireland, the stereotype is true. The grass really is that green. What is in your soil that causes this? Nitrogen?

It is a well watered island, for one, with climate moderated by the Gulf Stream, even though well north of the US (The Boston USA latitude 42+, Dublin 53+).

Soil compaction?

Any link to the actual study? Potential pitfalls of this kind of study:

- is the historical data available?

- is the decrease significant?

- is the sample size sufficient?

- is the sampling method reliable? (and conducted in the same conditions as the previous data points?)

- is there a difference between cultivated fields and uncultivated fields?

- is there any correlation between cultivation types and worm presence (not just usage of pesticides, but also types of cultures?)

- are there differences in soil properties (minerals, etc...)


I'd really like to have reporters link to the actual paper, or even better, datasets, in this time and age.

I may have taken part in this study with my kids at the Barnes Wetland Center last year. They had a kids ‘science’ event held during one of the school breaks, they had fun contributing to a “real” scientific experiment/survey.

We dug a hole of a specific size in a grassy field (the shovel was exactly the right dimensions) and counted how many worms we found in the soil to a set depth. We found a few worms, don’t remember the number or what should have been normal.

We also did a butterfly count there as well, which was less formal (not under guidance of a Wetlands worker). What was cool was meeting an amateur lepidopterologist at the time who pointed us towards several camouflaged cocoons in another area. Fun stuff.

> has shown they are rare or absent in two out of five fields

The title presumably should say 40%

Or is it 1 out of 5 fields? Big difference!

> 42% of fields studied had poor earthworm diversity

> 21% of fields lacked surface-dwelling worms

Seems pretty clear to me. Some vs. none...

Talking here about "earthworm diversity", is another thing that is wrong.

To identify earthworms is difficult even for experienced taxonomists and you need a microscope, a disection table and a lot of training. Polychaetes are much easier by comparison and I can assure you that they aren't easy. You need months of study.

Not, not everybody can do the work of a biologist. Not even the smartest children. Is complex, and hard work. Unless you want to classify the diversity of worms into "small", "medium sized" and "big worm", dig a hole and count isn't enough.

I think the 40% number is correct, the article also contains this line which is oddly specific to be a typo.

> However, 42% of fields had poor earthworm biodiversity – meaning either very few or none of the surface-dwelling and deep-burrowing categorisations of worms were seen.

And somehow the article has numbers to support both interpretations?

They took this Leave campaign too far.

Laughed more than I care to admit

Related anecdote: I moved to a small town in the West Midlands in the UK from Barcelona last year. One of the things I first noticed was an absence of nature sounds (but you can always hear a motorway, no matter how far you walk :( ). This is compared to living in downtown Barcelona in El Born. I finally figured it out after going back for a visit to Barcelona that there are just substantially fewer birds here, or at least in the area I live. I wonder if that's because there is less food for them?

Summer 2017 we were overwhelmed by snails and worm of various species. Summer 2018 was long, hot, and dry. We hardly saw any. But of course they are there. Occasionally, the cats drag in an earthworm. Last winter, mice moved into the house in numbers. We heard them occasionally saw them, cats were constantly on edge, and the mice somehow managed to thrive on catfood. This winter, not a rodent in sight. And this winter so far has been clement. come summer, I expect we'll see snails and worms and mice up to normal - though probably not excessive levels.

Not claiming there are no longer term downward trends. There may well be. I'm not qualified to judge. But often wonder why the huge year-to-year variability of small, fast-breeding species is so rarely touched upon in this kind of article. Small critters can bounce back in force within very short intervals, given anything resembling decent conditions.

I wonder what volume ‘a spadeful’ is? Presumably not a garden spade?

Edit: 20x20x20 cm volume. https://journals.plos.org/plosone/article?id=10.1371/journal...

Is this a relatively new development?

The article makes it seem like this hasn’t been studied in depth before (maybe just in the UK?). Sound like they were just trying to get baselines, and the next step would be to understand the whys.

Lots of worms in my garden. I did a survey yesterday...

Did anyone else notice that the article seems to be confused about "two fifths" versus "20 percent"?

Without more context the study is not very useful

pesticides, copper levels, phreatic level, number and species of hammerhead flatworms...

Those questions are exactly why a study like this is useful - we didn't know there was a problem, now we can ask the questions to find out what's going on.

We knew there was a problem since decades in fact, the disemination of tropical hammerhead flatworms that predate earthworms and can release the same neurotoxin as fugu fishes (in our potatoes?).

But we shouldn't fall in the temptation of making a mountain from a sand grain. Falling in gross extrapolation for clickbait purposes is as bad as no data. I can be wrong, but it seems that what we have here is an article done in part by volunteers and non professional ecologists (there is a variability in the observers), about a local area and in a narrow date interval.

Would be like to register what I ate the 23-Jan and assume that this is what I will eat for the rest of the year. Earthworm populations can raise and fall as a normal process.

And we should not mistake quantity by quality. I had analysed marine trophic chains and marine annelida appear everywhere. There is a huge biodiversity in sea worms. Huge loads of some species is bad, not good. Means that the ecosystem is in big trouble. With earthworms is the same. Not finding earthworms is not always a problem and finding a lot of them is not always good news.

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