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...
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 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.
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."
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%.
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.
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 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.
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.
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.
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.
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.
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.
Back then it was 1 hour or so - maybe a little less if traffic was good.
1.5 hours each way gets you into the “supercommuter” level but 1 hour each way is fairly common.
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.
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).
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."
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.
If you moved from a farm to Manhattan, we need to talk about the setup of this study :)
When it rains it is crawling with the things. Living in the forest and having an unpaved lot probably helps here.
They love cooking on that black top.
Not a great development for mushroom foragers.
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).
So maybe we should use some of the remaining 4984 species of worms as fish bait?
It's not perfect, but they are held to be a lesser of evils.
Something like permaculture could help. Chop and drop. Mulching on the spot.
Let's figure out how to fix this the right way, and now, before the remaining fields die off too.
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).
Also sampling bias.
- 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.
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.
The title presumably should say 40%
> 21% of fields lacked surface-dwelling worms
Seems pretty clear to me. Some vs. none...
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.
> 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.
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.
Edit: 20x20x20 cm volume. https://journals.plos.org/plosone/article?id=10.1371/journal...
pesticides, copper levels, phreatic level, number and species of hammerhead flatworms...
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.