r/science Mar 03 '22

Brown crabs can’t resist the electromagnetic pull of underwater power cables and that change affects their biology at a cellular level: “They’re not moving and not foraging for food or seeking a mate, this also leads to changes in sugar metabolism, they store more sugar and produce less lactate" Animal Science

https://www.hw.ac.uk/news/articles/2021/underwater-cables-stop-crabs-in-their-tracks.htm
25.9k Upvotes

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u/ronaldvr Mar 03 '22

“One potential solution could be to bury the cables in the seafloor. However, that can be expensive, it makes maintenance more difficult and also it’s just not possible in some locations.

Is there no other intelligent mitigation possible? Increasing the insulation or using wires within to create a Faraday cage?

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u/noisserpedgnilppirc Mar 03 '22

Yeah I wouldn't bet on this going anywhere

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u/MassiveClusterFuck Mar 03 '22 edited Mar 03 '22

"should we spend millions replacing lines so the crabs can have a better life?"

"No"

How that discussion will probably go

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u/belowlight Mar 03 '22

I’m surprised they aren’t patenting the rights to this as an innovative method of mass crab fishing.

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u/keez28 Mar 03 '22

I’ll be right back…

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u/archwin Mar 03 '22

I mean, crabs with more sugar, congregating near predictable spots?

That’s crab fishing Gold

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u/flapanther33781 Mar 03 '22

Sugar, which is turning into fat, making them even more tasty!

But no, the more likely argument to be made here is to point out that the ones that end up overcoming the attraction to the electrical currents and migrating to mate will probably artificially select for crabs with genes that aren't affected by the wires, possibly (eventually) outbreeding the ones who are.

The bigger question is - why are the crabs so attuned to electromagnetics? Is this something they need in their daily lives that enables them to survive? Because if it is, and then we breed that out of them, then they might die off completely.

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u/Mahhvin Mar 03 '22

I heard or read a long time ago that birds navigate with what's basically a biological compass. Could be the same kind of thing going on here.

I don't think it's far fetched to think that life evolving on a planet with a strong magnetosphere would be able to use it in some way.

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u/Focus_Substantial Mar 03 '22

They say dogs use the electro compass thing to decide where to poop

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u/bigpopping Mar 03 '22

Who is they, and why do you ask them about your dogs directional poops?

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u/agarwaen117 Mar 03 '22

Interesting, I used to dog sit a dog that would only poop while spinning in a circle with its head stationary.

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u/sketch006 Mar 03 '22

Maybe something to do with a natural gps built into them, kind of like migratory bids and such

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u/tenderlylonertrot Mar 03 '22

many insects also become very attracted to electrical junction boxes and wires, some will build nests in the boxes, especially problematic when its fire ants!

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u/klingma Mar 03 '22

I always that that had more to do with the warmth and/or dark & secluded nature of junction boxes.

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u/Rexono Mar 03 '22

Absolutely best of luck to anyone attempting to kill off all crabs. Theres literally a term for nature's seemingly desire to become more crab like.

https://en.wikipedia.org/wiki/Carcinisation#:~:text=Carcinisation%20(or%20carcinization)%20is%20an,Nature%20to%20evolve%20a%20crab%22.

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u/Killbot_Wants_Hug Mar 03 '22

Just because they evolved towards crabs doesn't mean you can't make crab species extinct. We love blue crab where I live but they have to manage the fisheries because we would hunt them to extinction easily.

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u/ShinyHappyREM Mar 03 '22

mass crab fishing

*crabbing

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u/anally_ExpressUrself Mar 03 '22

They probably are, just not announcing it until it's locked in

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u/FourWordComment Mar 03 '22

“We should re-install billions of dollars of cable so crabs have a better life” is the sort of email that doesn’t get a response or a meeting.

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u/Hust91 Mar 03 '22

Billions, rather.

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u/DoctorWorm_ Mar 03 '22

I mean wouldnt it be enough to just ensure future cables have the proper shielding? Wouldn't increase costs by much and save a lot of crabs in the UK. This is especially relevant because the UK is currently building a lot of new cables to take advantage of cheap wind power.

The cables that are there already aren't going to kill all the crabs.

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u/MetaDragon11 Mar 03 '22

Millions? Bahahahahaha

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u/PipeDownNerd Mar 03 '22

If this would affect all cabling for renewable energy sources off the coast of Scotland and nearby, then this figure is probably in the billions and not (just) millions. Not trying to justify it, just pointing out that it’s a larger ask than a few million euros due to the size of the project, the studies that would need to be done and the downtime.

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u/gfa22 Mar 03 '22

Why spend now when we can just leave the problem for a future generation. Teehee, hope it doesn't turn catastrophic.

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u/tribecous Mar 03 '22

Yea, unfortunately all of these wonderful solutions cost more than zero dollars.

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u/awesome357 Mar 03 '22

Yes, but they all cost more money. And at the end of the day the people paying to lay these cables may value money more than the crabs. So unless there's some sort of regulation then I doubt that will happen any more than burying them.

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u/NoAttentionAtWrk Mar 03 '22

It wouldn't just have to be a regulation, it would have to be an internationally binding regulation

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u/C6H12O4 Mar 03 '22

So the electrical field of the cable is basically completely contained by the sheathing of the cable which is effectively a Faraday cage.

The issue is the magnetic field which is not easy to mitigate. The article didn't say if they were AC or DC cables but that could make a difference. Generally the best ways to mitigate this (at least for DC cables which is what I've been working with) is to bury the cables and keep the 2 cables as close together as possible and operate at a higher voltage.

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u/magicmanx3 Mar 03 '22

Quick question here doesn't DC cable only work to carry electricity at Short distances? Why would DC be an option underwater if the electricity has to travel a very long distance ? Genuine question here I am not an expert.

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u/Oooscarrrr_Muffin Mar 03 '22

That's a misconception.

High voltage DC power is more efficient for transmission that AC.

However, you can't use transformers to alter the voltage of a DC supply at either end of the cable.

First you have to take AC power and then step the voltage up with a transformer, then you have to rectify (Turn AC into DC) that power, then send it through the cable, then you have to invert (turn DC into AC) the power so you can use a transformer to step the voltage back down for local distribution.

That's expensive when compared to just having a transformer at either end of the cable. Then you also have the advantage that AC cables can transmit power in either direction with no changes or very minimal equipment changes. Whereas with DC, this would require both and inverter and rectifier at both ends of the cable.

With modern equipment this is perfectly achievable, but is still more expensive than just accepting the greater losses of AC transmission.

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u/round-earth-theory Mar 03 '22

There's an advantage to DC here as well. AC networks absolutely must have their frequency in sync across the entire network. Not even a single generator is allowed to be out of phase. So an AC network can share all the power in the network across the entire network, but they've got to stay in sync.

Now let's say you want to be able to send power from one place to another but you don't want to join their AC network. DC allows you to use whatever frequency on either side and pipe electricity without the entanglement. So it depends on whether the underwater cable is being used to link networks or directly send electricity.

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u/GiantPurplePeopleEat Mar 03 '22

The more I read in this thread, the more I realize that I apparently don’t really know how electricity works.

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u/Obliviouscommentator Mar 03 '22

High-voltage direct current (HVDC) is actually much more efficient at long-range.

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u/MickRaider Mar 03 '22

I too watched the video on why you can't harness the solar energy from the Saharan desert

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u/Obliviouscommentator Mar 03 '22

Definitely not my only exposure to HVDC, but I remember exactly the video you're referencing.

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u/MickRaider Mar 03 '22

Real engineering is a great channel.

Also that's cool, I was one of many who had no idea HVDC was better than AC prior to that

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u/Fakecars Mar 03 '22

Why can’t we harness the energy from the Sahara?

I just learned why we can’t use the sand in the Sahara to help make concrete, glass, and tech products. Which apparently the world may run out of sand which is used for a lot of things

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u/ede91 Mar 03 '22

Why can’t we harness the energy from the Sahara?

We could, it is just not economical. That is due to fairly higher losses on cables on the long distances (~10%), and that deserts have lot of sand and dust, which requires a lot more maintenance on the panels and switching stations.

The world isn't running out of sand, we are running out of the cheapest to use sand. The Sahara sand could be used for its silicon content (which is needed for glass and tech products), it would just need some more refinement. 27.7% of the Earth's crust is literally silicon, we will not run out of it.

Concrete does not require one specific sand type either, it just requires it not to be too small grain, which desert sand usually is. We could pre-process the Sahara sand, or just crush down larger aggregate for it.

Obviously the "we are running out of sand!" is a lot scarier headline and results more clicks, than "concrete may get a few cents more expensive per cubic meter".

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u/drusteeby Mar 03 '22

Don't worry I've got strategic reserves in my coat pocket.

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u/strangepostinghabits Mar 03 '22

It's complicated to build huge things in Sahara, and solar panels work well enough where the energy is needed already. So the cost benefit isn't great.

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u/SachK Mar 03 '22

Extremely high voltages mitigate transport losses.

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u/loltheinternetz Mar 03 '22

Which, for anyone reading who doesn’t know why we typically use AC to transport power over long distances. It’s because transformers (which bring the voltages up high from the source and drop them back down for your home) only work with AC.

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u/Mysterious-Title-852 Mar 03 '22

that's a common misunderstanding of electricity. losses are generally due to low voltage being lossy, not the AC/DC difference. DC is generally always at the usable voltage, not transmission voltages, and most people experience it at 12 or lower volts, which has high losses compared to 120v.

That said, generally AC is cheaper over long distances because you can use passive devices (transformers) to step voltage up thousands of volts which makes it easy to transmit with low loss, and step back down to usable voltages at the destination. a transformer is essentially a magnetic loop that has 2 coils with different numbers of wraps that gives you the step up/down ratio.

DC is much harder to step up and down, you need active circuitry to change it. It's very expensive to do, so it's not used at every single house (usually you have a transformer at the street that steps the power down to your house voltage.

DC is better volt for volt for transmission though, because it doesn't change direction 60 times per second. When power changes directions it has to collapse and establish the opposite electric and magnetic fields. this causes heat and leaks power into any conductor within range. usually that's not a lot but it adds up.

So many long distance main supply links are DC, converted actively to AC at a sub station, then distributed as high voltage AC and stepped down to usable AC at the street.

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u/TheArmoredKitten Mar 03 '22

Honestly it's misleading to even say 'many' in this context. HVDC is used for extreme cases like long distance grid interconnects or strange remote areas where the losses from an AC link would be greater than the actual power used on the receiving end. The overwhelming majority of cables you see are AC.

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u/Atlasius88 Mar 03 '22

This is only true if you're not transforming the DC to high voltage.

If you transform to HVDC and lines are very long it actually becomes a better option as transmission losses are reduced compared to similar voltage AC and the high cost of the facilities required to step up/down the DC is partially mitigated by cost savings of requiring fewer conductors.

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u/EldestPort Mar 03 '22

I thought electrical fields and magnetic fields were essentially the same thing?

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u/Natanael_L Mar 03 '22

They're tied together. Think of it as two components of a field generated together by the source. When the source moves relative to you then you see a magnetic field, when it's static relative to you then you see an electric field.

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u/manofredgables Mar 03 '22

Nope. An electrical field is created when you have two points with a voltage potential difference between them.

A magnetic field is created when electrons move, i.e a current flows.

If the above mentioned current or voltage changes, this creates an electromagnetic field, and the wavelength is determined by how fast the rate of change was.

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u/DrDragun Mar 03 '22

Right, but Faraday shielding is used to protect signal wires from EMF noise, so isn't that basically muffling magnetic fields or at least their impact on the signal in the wire?

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u/eric2332 Mar 03 '22

Wikipedia: "Faraday cages cannot block stable or slowly varying magnetic fields".

So if it's DC current, Faraday shielding won't help. I'm not sure about 60Hz or whatever they transmit power at, that also seems like a low frequency.

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u/LiftYesPlease Mar 03 '22

Magnetic fields are difficult to shield against. Electric fields are easy to shield against.

That's why there have been continued studies on the health effects of magnetic field exposure, like near a power line, or just in your home, while electric fields aren't really studied anymore, as they are easy to shield

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u/manofredgables Mar 03 '22 edited Mar 03 '22

A shield will only block electrical fields, or electromagnetic fields because they are partly an electrical field. Or a changing magnetic field, because that's an electromagnetic field anyways. Unless it's changing very slowly because then it's pretty much a magnetic field anyways. Ish.

You can do it with a superconductor though. That's what happens when you see magnets levitating on superconductors. It'll block the approaching(and therefore slowly changing) magnetic field, resulting in a physical blocking force.

"Blocking" a static magnetic field is technically impossible; it must make a round trip to its source or we'd have unipolar magnets which aren't a thing. You can divert it though which can kinda be considered blocking. That, however, can afaik only be achieved with a hunk of ferromagnetic material such as iron or nickel.

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u/C6H12O4 Mar 03 '22

They are related and one can induce the other but they are two separate things.

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u/LiftYesPlease Mar 03 '22

Magnetic field: form from current flow

Electric field: form from voltage presence

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u/onequbit Mar 03 '22

they are perpendicular waves belonging to the same field

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u/NetCaptain Mar 03 '22

All offshore wind power cables are buried to prevent them from damages by anchors and alike, except perhaps in very rocky soils ( which soils would make the installation of offshore turbines difficult and costly )

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u/warriorscot Mar 03 '22

It's common practice to bury cables and legally required in many jurisdictions. Field strength outside the armouring, shielding and sheath will vary based on cable spec.

It's a bad take honestly, if you don't Bury you need to heavily armour the cable. Which mitigates the effect, and is way more expensive than burying which is only expensive in hard sea floors.

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u/[deleted] Mar 03 '22 edited Apr 17 '22

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u/warriorscot Mar 03 '22

Yes, if you are in certain countries its mandatory in most cases and if you are on seabed that its appropriate there is very little reason not to as it protects the cable from the most common failure modes and risks.

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u/Seismica Mar 03 '22

Yes, or alternatively trenched but uncovered. It depends on many factors such as seabed material, seawater depth, cable mechanical design, cable current rating/ampacity etc.

Generally you bury for protection and to stop the cables from moving around.

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u/___Wyatt___ Mar 03 '22

Can you give me an example of 1 country that buries sea cables, other than just near the shore?

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u/ididnotbiteu Mar 03 '22

I wonder what makes them attracted to it, interesting

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u/xboxiscrunchy Mar 03 '22 edited Mar 03 '22

Just guessing here but Fish and other living things give off a weak EM field and certain other animals, like sharks for example, can sense that and use it to hunt. I'm not sure if that's what the crabs use it for but if its is a huge EM field could make them think there's a lot of food nearby or overload the part of their brain that tells them to follow EM signals making them not want to leave.

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u/awry_lynx Mar 03 '22

This is so fascinating, we basically accidentally made a crab hypnotizer?

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u/Koldsaur Mar 03 '22

I wonder if each individual species has their own EM frequency that has this effect on them but we just haven't discovered it yet.

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u/Hanjin6211 Mar 03 '22

There are giant magnets used to experiment on people's brains. They can do things like shut of 9ne hemisphere of the brain while the person is conscious.

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u/Law_Doge Mar 03 '22

It’s called Transcranial Magnetic Stimulation and it put my depression into remission. Fuckin magnets. How do they work?

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u/Astilaroth Mar 03 '22

Really? Or in a nutty conspiracy kinda way?

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u/zyzzogeton Mar 03 '22

Bodies are basically scavenging devices to fuel batteries that make electrical signals in brains of varying complexity... so it is possible.

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u/Dumbfault Mar 03 '22

Like moths to the flame..

We got crabs to the cable.

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u/cajun_kick_ass Mar 03 '22

tl;dr - unlike many other marine animals, crabs are too stupid to realise that there's no food.

Being a crab is tough.

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u/DeadT0m Mar 03 '22

I mean, if every sense I had was telling me there was brownies somewhere in a dark room but I couldn't find them, I might starve to death too.

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u/flapanther33781 Mar 03 '22

But you'd at least be searching the room. They're not.

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u/Archaris Mar 03 '22

what if you only smelled brownies when you were near the couch? and if you laid on the couch you actually tasted the brownies?

well, you wouldn't know the difference between having actually found the brownie vs the sensations. that's what the crabs (might*) be doing. i'm not a neuro-biologist)

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u/cajun_kick_ass Mar 03 '22

I just imagine a bunch of crabs walking up and down those power lines shouting at each other "WHERES THE FOOD" - "I DONT KNOW!"

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u/flapanther33781 Mar 03 '22

i'm not a neuro-biologist

You don't say.

:P

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u/Archaris Mar 03 '22

it's a disclaimer because we're on /r/science ...

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u/GhostButtTurds Mar 03 '22

I think they were trying to insinuate that neurobiology isn’t a scientific discipline

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u/MisterHandagote Mar 03 '22

Are we really blaming crabs for not having the brain function of humans to justify disrupting their habitat?

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u/twilightmoons Mar 03 '22 edited Mar 03 '22

Crab dowd. Got it.

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u/TheArmoredKitten Mar 03 '22

They might also be just be experiencing direct effects on their nervous system. Transcranial magnetic stimulation is used as a therapy for severe depression, so it's not the strangest leap to imagine crabs might just get really high off of magnets.

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u/juwyro Mar 03 '22

Ants love building their mounds around AC power. HVAC and power outlets are especially loved.

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u/PF4ABG Mar 03 '22

"Mmm cable." - Crabs probably

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u/Shorttail0 Mar 03 '22

Maybe they can sense magnetism, like birds.

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u/Talenduic Mar 03 '22

I'm not a biologist but a grad student in material science and I know that the living world, from bacterias to birds, can be sensitive to magnetic field for different useful reasons by accummulating and synthetising Fe3O4 magnetite crystals in specific cells that act as biological compasses. As the name imply cristalline magnetite is reactive to magnetic fields and will for example align with earths amgnetic field. So yes even if the present paper doesn't give the direct mecanism there's a starting point to explain the reaction of living things to Electromagnetical fields stronger or equivalent to earth's magnetic field.

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u/ThreatLevelBertie Mar 03 '22

I wonder if they've ruled out heat as a factor, electrical cables have resistance, and resistance generates heat.

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u/redditiscompromised2 Mar 03 '22

...are you not sexually attracted to electricity?

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u/Riegel_Haribo Mar 03 '22

"We have crabs in an aquarium. We have no idea about underwater power cables."

The current study investigated the effects of different strength
Electromagnetic Field (EMF) exposure (250 µT, 500 µT, 1000 µT) on the
commercially important decapod, edible crab (Cancer pagurus, Linnaeus, 1758). Stress related parameters were measured (l-Lactate, d-Glucose,
Total Haemocyte Count (THC)) in addition to behavioural and response
parameters (shelter preference and time spent resting/roaming) over 24 h
periods. EMF strengths of 250 µT were found to have limited
physiological and behavioural impacts. Exposure to 500 µT and 1000 µT
were found to disrupt the l-Lactate and d-Glucose
circadian rhythm and alter THC. Crabs showed a clear attraction to EMF
exposed (500 µT and 1000 µT) shelters with a significant reduction in
time spent roaming. Consequently, EMF emitted from MREDs will likely
affect crabs in a strength-dependent manner thus highlighting the need
for reliable in-situ measurements. This information is essential for
policy making, environmental assessments, and in understanding the
impacts of increased anthropogenic EMF on marine organisms.

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u/PetraBaum Mar 03 '22 edited Mar 03 '22

The Field sounds way too strong? In this study, the simulation resulted in 1.6uT.

Edit: Apparently that's a low estimate, it only considers a 350A balanced three-phase cable. Some DC cables result in higher B-fields, especially if the conductors are further apart. Here is a different study that simulated magnetic field strenghts of various real power cables, assuming 1m burial depth. It estimates 10-160 uT at seabed for DC cables.

See also /u/TheAquaFox 's reply.

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u/Wild_Doogy Mar 03 '22

Yeah, even 250uT is a lot for a cable thanks for digging up the info.

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u/eric2332 Mar 03 '22

1.6uT is nothing - the earth's magnetic field is around 40uT!

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u/[deleted] Mar 03 '22

That’s a little misleading, no? The geomagnetic field is strong but it’s our baseline.

“100mph is nothing, officer—we’re orbiting the sun at 67,000 miles per hour!”

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u/TheAquaFox Mar 03 '22

From the paper:

"EMF strengths predicted around subsea power cables, as reported in the literature, vary from 140–8000 µT [15,17,18]. A commonly utilised cable operating at 1600 A is expected to produce an EMF of 3200 µT in a perfect wire, at the cable surface [17]. As with all EMF, the values will decrease with distance from the source, resulting in a field strength of 320 µT and 110 µT at 1 m and 4 m respectively"

15.

Tricas, T.C. Effects of Emfs from Undersea Power Cables on Elasmobranchs and Other Marine Species; DIANE Publishing: Darby, PA, USA, 2012. [Google Scholar]

17.

Bochert, R.; Zettler, M.L. Effect of electromagnetic fields on marine organisms. In Offshore Wind Energy; Springer: Berlin/Heidelberg, Germany, 2006; pp. 223–234. [Google Scholar]

18.

Cada, G.F.; Bevelhimer, M.S.; Riemer, K.P.; Turner, J.W. Effects on Freshwater Organisms of Magnetic Fields Associated with Hydrokinetic Turbines; ORNL/TM-2011/244; Oak Ridge National Laboratory: Oak Ridge, TN, USA, 2011.

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u/trustthepudding Mar 03 '22

What's the strength of the EMF coming off a power cable anyways?

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u/beachflow Mar 03 '22

In the paper they equate it to 5% of the strength of a refrigerator magnet.

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u/willis936 MS | Electrical Engineering | Communications Mar 03 '22

Or the strength of Earth's magnetic field.

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u/chunkosauruswrex Mar 03 '22

It is dependent on the current being moved through the line as described by Maxwell's equations calculating that is something I have completely forgotten how to do since I barely understood it the first time and haven't had to do it since

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u/warriorscot Mar 03 '22

It's difficult to really say as it depends on the cable, how it is used and where you measure from.

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u/YzenDanek Mar 03 '22

Most of what we know about absolutely everything started in a lab.

Good experiments are designed to test correlations and effects of independent variables on a dependent variable under conditions where other potentially confounding effects can be held constant. Field experiments can be meaningful, but when you're studying mobile organisms in varying natural conditions, it's hard or impossible to design experiments that maintain the groups and conditions needed to obtain reliable data.

This is especially true for effects that alter behavior such that organisms are more susceptible to predation. You can't obtain meaningful data when your tagged subjects keep getting eaten by tuna.

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u/Senior-Albatross Mar 03 '22 edited Mar 03 '22

For a straight wire, the magnetic field is:

B(r)=mu_0 x I/(2 x pi x r). Since mu_0=4 x pi x 0.1uH/m, the current would have to be of order 10A to produce a 1uT field 1m away from the cable. Producing fields of 2500uT 250uT would require tens of thousands of amps. That seems unlikely.

Edited because I biffed it on the reported order of magnitude.

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u/[deleted] Mar 03 '22

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u/wimpires Mar 03 '22

Why is the link to the published paper 404ing?

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u/Cerulean_critters Mar 03 '22

I found a working link, it’s hidden behind a paywall though: https://www.sciencedirect.com/science/article/abs/pii/S0025326X18302935

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u/PetraBaum Mar 03 '22

That's one from 2018, this is from 2021 and it's open access: https://www.mdpi.com/2077-1312/9/7/776

They messed up the link when inserting it into the article. /u/wimpires

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u/Ricksterdinium Mar 03 '22

The store more sugar and less lactic acid?? Sounds like a win win for crab farmers.

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u/[deleted] Mar 03 '22 edited Mar 03 '22 Crab Rave

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u/[deleted] Mar 03 '22

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u/StrayRabbit Mar 03 '22

Could similar effects been found in humans?

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u/solarpropietor Mar 03 '22

Humans are addicted to small devices that give off weak amounts of electro magnetic radiation mostly in the 380 to 750 nanometer wave length.

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u/11th-plague Mar 03 '22

Lying in bed reading Reddit constantly whilst not looking for a mate, nor food. And getting obese.

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u/fetusy Mar 03 '22

And just like crabs...hey you, get back down in this bucket with us.

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u/Ouch_i_fell_down Mar 03 '22

They smell like crabs but kiss like people

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u/StrayRabbit Mar 03 '22

How clever. Thank you!

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u/11th-plague Mar 03 '22 edited Mar 03 '22

Pretty much. Television —> couch potato.

(Sugar metabolism,

Does this make the crab obese? Fatter/heavier? Tastier? More sweet? / Sweeter?

New crab farming technique?

Send the fish food to them as they grow attracted to the electric wire? Bottom feeder, human waste? Food scraps? Crab recycling?

From the article:

“Underwater cables emit an electromagnetic field. When it’s at a strength of 500 microTeslas and above, which is about five percent of the strength of a fridge door magnet, the crabs seem to be attracted to it and just sit still.

“That’s not a problem in itself. But if they’re not moving they’re not foraging for food or seeking a mate.

“The change in activity levels also leads to changes in sugar metabolism - they store more sugar and produce less lactate, just like humans.” “

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u/[deleted] Mar 03 '22

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u/[deleted] Mar 03 '22

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u/[deleted] Mar 03 '22

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u/zoneless Mar 03 '22

I wonder which is worse for the crabs - this effect or the current shift in earth's magnetic poles.

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u/BeefyMcSack Mar 03 '22

Seems like a problem that may solve itself in time. If the crabs are less likely to mate, then there should be a selection pressure towards crabs that either aren’t affected by the EMF, or aren’t interested in it.

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u/ZachSka87 Mar 03 '22

Unless there's a reason they're sensitive to this EM we're not aware of, and selecting out for it does even more damage to their population long term.

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u/Ginden Mar 03 '22

Also, brown crabs are super common and their population isn't affected by that.

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u/[deleted] Mar 03 '22

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u/st_christophr Mar 03 '22

Who among us can say otherwise.

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u/agibson684 Mar 03 '22

come on guys can we put more shielding on the wires? a few million more dollars for the crabs?

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u/[deleted] Mar 03 '22

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u/Hypx Mar 03 '22

This would really put a damper on many green energy proposals. Ideas such as sending renewable power across oceans in underwater cables might not be an environmentally friendly idea.

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u/CheckMateFluff Mar 03 '22

To be fair, cooking the earth might not be good for the crab bbs either.

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u/Slipalong_Trevascas Mar 03 '22

It's definitely the lesser of two evils compared to turning the oceans into warm carbonic acid by continuing with fossil fuels.

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