Hundreds of sharks and rays tangled in plastic

Hundreds of sharks and rays tangled in plastic
An adult shortfin mako shark entangled in fishing rope (biofouled with barnacles) in the Pacific Ocean, causing scoliosis of the back Credit: Daniel Cartamil

Hundreds of sharks and rays have become tangled in plastic waste in the world's oceans, new research shows.

University of Exeter scientists scoured existing published studies and Twitter for shark and ray entanglements, and found reports of more than 1,000 entangled individuals.

And they say the true number is likely to be far higher, as few studies have focussed on plastic among shark and rays.

The study says such entanglement—mostly involving lost or discarded —is a "far lesser threat" to and rays than , but the suffering it causes is a major animal welfare concern.

"One example in the study is a shortfin mako shark with fishing rope wrapped tightly around it," said Kristian Parton, of the Centre for Ecology and Conservation on Exeter's Penryn Campus in Cornwall.

"The shark had clearly continued growing after becoming entangled, so the rope—which was covered in barnacles—had dug into its skin and damaged its spine.

"Although we don't think entanglement is a major threat to the future of sharks and rays, it's important to understand the range of threats facing these species, which are among the most threatened in the oceans.

"Additionally, there's a real animal welfare issue because entanglements can cause pain, suffering and even death."

Hundreds of sharks and rays tangled in plastic
Hundreds of sharks and rays have become tangled in plastic waste in the world's oceans, new research shows. Credit: Martin Stelfox

Co-author Professor Brendan Godley, co-ordinator of the university's marine strategy, added: "Due to the threats of direct over-fishing of sharks and rays, and 'bycatch' (accidental catching while fishing for other species), the issue of entanglement has perhaps gone a little under the radar.

"We set out to remedy this. Our study was the first to use Twitter to gather such data, and our results from the social media site revealed entanglements of species—and in places—not recorded in the academic papers."

The review of academic papers found reports of 557 sharks and rays entangled in plastic, spanning 34 species in oceans including the Atlantic, Pacific and Indian. Almost 60% of these animals were either lesser spotted dogfish, spotted ratfish or spiny dogfish.

On Twitter, the researchers found 74 entanglement reports involving 559 individual sharks and rays from 26 species including whale sharks, great whites, tiger sharks and basking sharks.

Both data sources suggested "ghost" fishing gear (nets, lines and other equipment lost or abandoned) were by far the most common entangling objects. Other items included strapping bands used in packaging, polythene bags and rubber tyres.

The study identified factors that appear to put certain species more at risk:

  • Habitat—sharks and rays in the open ocean appear more likely to get entangled, as do those living on the sea floor, where materials such as nets loaded with dead fish sink and attract predators, which in turn get stuck.
  • Migration— that cover long distances appear at more at risk of encountering plastic waste.
  • Body shape—sharks seem to be at greater risk than rays. Species with unusual features—such as manta rays, basking sharks and sawfish—are also at more risk.

The study says more research is needed, and the researchers have worked with the Shark Trust to create an online report form to gather data on entanglements: https://recording.sharktrust.org/entanglement/record

The paper, published in the journal Endangered Species Research, is entitled: "A global review of shark and ray entanglement in anthropogenic marine debris."


Explore further

Official stats mask shark and ray species caught in the Mediterranean and Black seas

More information: KJ Parton et al, A global review of shark and ray entanglement in anthropogenic marine debris, Endangered Species Research (2019). DOI: 10.3354/esr00964
Citation: Hundreds of sharks and rays tangled in plastic (2019, July 5) retrieved 24 July 2019 from https://phys.org/news/2019-07-hundreds-sharks-rays-tangled-plastic.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
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User comments

Jul 05, 2019
This is obvious
The question is
For as our food supply diminishes
What to do about it?


Jul 06, 2019
First of all, if at all possible, the sharks and other fish must be freed from the plastics and whatever plastics are found be taken from the ocean and recycled.
Second, all those nations who are responsible for throwing plastics into the oceans should be warned to cease and desist or suffer financial consequences.
Third, everyone should remove paper labels from plastics, whether soft or hard plastics, so that they can be recycled without being contaminated with paper.
Fourth, the IPCC should be more aware of and concerned about these animals and fish in the ocean dying due to insensitivity and carelessness on the part of humans. That is an immediate problem and should be number one on their list.
Fifth, the sea shores, rivers, streams should all be patrolled by volunteers to go after humans who litter with plastics. Fining them plus a court appearance before a judge may convince human to become better stewards of the Earth.
Repeat offenders should be jailed.

Jul 06, 2019
The problem is plastic packaging

SEU
Sugar is in paper bags
Eggs are in cardboard boxs
These fruit packers
Instead of ordering plastic bags from their trade suppliers
The time is nigh to order paper bags and cardboard cartons
For apples come in cardboard boxs from around the world
As these can be supplied direct to supermarkets
And placed directly on Tesco's shelves
For we the customers to place in paper bags

Plastic packing is the key
As what is the point of putting 6 apples in a cardboard cartons wrapped in plastic

When eggs and sugar still comes in cardboard and paper packing

Jul 06, 2019
We should all act to reduce our use and disposal of plastic but as the article notes, commercial fishing is a much greater problem for these (and other) species. The best way we as individuals can help them is to not consume fish or other animals/animal products. All of the nutrients we need in order to thrive can be obtained more healthfully, humanely, and environmentally responsibly from plant sources. There are marvelous vegan versions of virtually every type of food imaginable, including seafood: http://www.FishFe.../seafood

Jul 06, 2019
When I was in the Navy back during the Vietnam War, our aircraft carrier sailed up and down the coast about 100 miles offshore, approximately between San Francisco and San Diego. 4 or 5 times a day would dump our garbage which consisted of plastic refuge, cans, etc. off the back of the ship.

Considering that this has been going on since before world war 2 until the present day, I am pretty sure that practice alone could account for most of the vast amount of trash found in the Pacific, particularly since the zone where the plastic is found roughly corresponds to that part of the ocean.

Jul 06, 2019
plastic waste? in the oceans? take your complaints to the sources

Jul 06, 2019
Science as practised by humans is responsible for creating this mess, and it will have to be science to find the solutions for cleaning it up and to stop the suffering of innocent animals. There is very little time to waste in thinking and wondering. It has to be done ASAP, as it is not only the animals of the Seas that suffer, but their demise will also impact human life.

Genesis in the Bible stipulates that mankind is to be the stewards of the Earth and all that is in it. But through self-centredness, complete disregard, and plain stupidity, humans have been neglecting certain responsibilities that were given to them. In this 21st century where most are allegedly well-educated, at least adequately, there is very little concern over the responsibilities given to mankind, whether they are religious, agnostic or atheist. Many don't believe that humans were given this stewardship by a Creator God, so they consider it to be mythology. And yet, the Truth becomes more apparent.

Jul 06, 2019
We should all act to reduce our use and disposal of plastic but as the article notes, commercial fishing is a much greater problem for these (and other) species. The best way we as individuals can help them is to not consume fish or other animals/animal products. All of the nutrients we need in order to thrive can be obtained more healthfully, humanely, and environmentally responsibly from plant sources. There are marvelous vegan versions of virtually every type of food imaginable, including seafood: http://www.FishFe.../seafood
says MaryF

Unfortunately, humans are a meat-eating animal and the nutrients found in animal meat are required by the human body. The teeth of humans are meant for grinding and chewing meat, seeds and nuts; even gnawing on bone for the marrow. Humans have evolved in this manner due to hunting in early epochs even before they became agrarian.
Yes. Fish feel pain due to their nervous systems. But in the wild they get eaten by other fish.

Jul 06, 2019
-contd-
Do fish feel any less pain if they are eaten by other fish instead of humans?
The same goes for cattle, goats, sheep, and other mammals. In the wild if they aren't domesticated, they are eaten by other animals who are predators. Does a steer or sheep feel any less pain if they are eaten by a wild mountain lion, for example, instead of being slaughtered as humanely as possible for human consumption?
I have heard that the Muslim practise of slaughtering animals is cruel, harsh, painful and merciless. I disapprove of such a hurtful practise as it is unnecessary to inflict pain on the very animal that you are going to cook and eat.

Jul 06, 2019
@Parsec
I think that I speak for all in this physorg phorum when I say, Thank you for your service in the USNavy during a time of war in Vietnam.
Approximately 53,000 American lives were lost there as well as others from other nations. Glad that you made it home.
:)

Jul 07, 2019
Science as practised by humans is responsible for creating this mess,
Surveillance_Egg_Unit

Science isn't responsible for creating this mess. Politics and humans are responsible for creating this mess and politics and humans aren't science. Science is merely the knowledge completely rationally obtained via documented evidence and/or sound logic. But science doesn't tell us what we morally should do with that knowledge once we have obtained it and has no say on what is moral thus science is blameless, and that includes being blameless for its misuse. To blame science is like blaming the knowledge that went into manufacturing a car that a drunk driver killed someone with rather than blame the driver, or like blaming the first ever human to discover fire whenever you burn yourself.

Jul 07, 2019
Unfortunately, humans are a meat-eating animal and the nutrients found in animal meat are required by the human body.
Surveillance_Egg_Unit

All the essential nutrients required by the human body can be obtained from eating only dairy products and plant matter alone thus there is absolutely no need for any of us to eat animal meat.
I am one of many people that never eat animal meat and we have shown no ill-health from merely doing this.
Admittedly, I think it would be significantly harder (but certainly not impossible) to obtained all of the required nutrients from eating plant matter alone without any dairy products thus I personally wouldn't recommend stop eating ALL animal products in particular. But that doesn't change the fact we can easily do away with eating meat without ill-effect.
We could also farm and eat insects and that would generally have much less environmental impact than other meats.

Jul 07, 2019
Second, all those nations who are responsible for throwing plastics into the oceans should be warned to cease and desist or suffer financial consequences
The professional troll known as SEU/obamasocks/jewsrule/racistblackguy/pussycateyes et al thinks we should blame India for their polluters. This is the same as blaming the US for all the garbage SEU regularly dumps in these threads.

This would be impractical and ineffective.
I think that I speak for all in this physorg phorum when I say, Thank you for your service in the USNavy during a time of war in Vietnam
I think parsec is savvy enough to recognize a phony butt-sucking troll when he sees one, having been here long enough to have witnessed all the many degenerate iterations of this particular troll from pirouette to the present.

A troll who is only here to vandalize and flood this site with deliberate baiting ignorance.

SEU - sucking up was a particular favorite of your obamasocks sock, remember? We do.

Jul 07, 2019
Unfortunately, humans are a meat-eating animal and the nutrients found in animal meat are required by the human body.
Surveillance_Egg_Unit

All the essential nutrients required by the human body can be obtained from eating only dairy products and plant matter alone thus there is absolutely no need for any of us to eat animal meat.
I am one of many people that never eat animal meat and we have shown no ill-health from merely doing this.
Admittedly, I think it would be significantly harder (but certainly not impossible) to obtained all of the required nutrients from eating plant matter alone without any dairy products thus I personally wouldn't recommend stop eating ALL animal products in particular. But that doesn't change the fact we can easily do away with eating meat without ill-effect.
We could also farm and eat insects and that would generally have much less environmental impact than other meats.
says humy

Cooking and eating meat is a pleasure to many

Jul 07, 2019
-contd-
@humy

Every human is able to make their own choice whether or not to eat meat. It would be a sad day if in the future a dictatorship was able to disallow humans anywhere to make their own choice, and force everyone to eat plant life without meats. My human host loves his steaks, chops, burgers along with a salad and potato or rice. That is his choice. But as I said, humy, there are predators who willl gladly dine on such animals that are meant for humans to eat, as well as humans and other animals.
Hunter-gatherers also loved cooking and eating meat and fish along with grains. Somehow they survived and had children who had filled the Earth with their descendants, so eating meats couldn't have been all that bad.

Jul 07, 2019
-contd-
@humy

WRT science being responsible, a human who never experimented with how to create plastics from petrol is a human who doesn't do science wrt plastics. Of course, there are many kinds of science. Even inventing a clock is a form of science and engineering.
But without Science, humy, such things would not have been invented, and humans would still be riding horseback or walking to market and running into caves to get out of the rain.
So science IS responsible in a secondary way, for it is the human MIND that conceives of science and engineering and maths.
But I blame both humans and science for the suffering of these animals. Throwing plastics into the oceans and rivers is a combination of stupidity and carelessness. And a bit of evil also. They KNOW that there are life forms in the oceans, and yet they just don't give a damn.

Jul 07, 2019
Unfortunately, humans are a meat-eating animal and the nutrients found in animal meat are required by the human body.
Surveillance_Egg_Unit

All the essential nutrients required by the human body can be obtained from eating only dairy products and plant matter alone thus there is absolutely no need for any of us to eat animal meat.
I am one of many people that never eat animal meat and we have shown no ill-health from merely doing this.
Admittedly, I think it would be significantly harder (but certainly not impossible) to obtained all of the required nutrients from eating plant matter alone without any dairy products thus I personally wouldn't recommend stop eating ALL animal products in particular. But that doesn't change the fact we can easily do away with eating meat without ill-effect.
We could also farm and eat insects and that would generally have much less environmental impact than other meats.
says humy

Eating Dairy products depends on cows, sheep,

Jul 07, 2019
@humy
...cows, sheep and other grass eaters whose milk is forcibly taken and consumed by humans such as you, where that milk is made in the cows' udders to feed their calves. So basically what you are doing when you drink the milk of cows, sheep, goats, etc. is using the protein and calcium that is in the milk that is meant for nourishing the young animals. Is this fair to the baby animals?
You take their milk for yourself and believe that it is better than humanely slaughtering a steer to consume its meat. The nutrients are in both milk and meat, except that meat has much more iron, IIRC. But it goes without saying, that you are stealing the milk from the mouths of calves and other baby animals so that you can say that you don't eat meat. You may not realise that the milk that you are stealing from a baby contains the fat and nutrients that would help the baby to grow. Would you do that to a HUMAN baby?

Jul 08, 2019
Hundreds of sharks and rays have become tangled in plastic waste in the world's oceans, new research shows.

Strange. I can't think of any plastic waste that would entangle sharks. Oh wait, they were talking about discarded fishing nets. So ultimately there is no "solution" because fishing nets aren't going away and they accidentally wash overboard all the time. Far more sharks and sea mammals are killed in nets while hauling in their catch than in discarded nets. Thank you for bringing our attention to a minuscule problem.

Jul 08, 2019
ROFLOL
Otto, YOU are such a LIAR. I have only THIS ONE USER NAME and ONLY this one. And I am NOT granville nor am I rrwillsj or anyone else. Try to get that through your thick Nazi skull, you ugly fat dingaling nut job.
And why don't you just admit that you HATE competition and new ideas. And I notice that you hated Pirouette for her proof of Martian life forms. Yes, I saw her pictures on her website.

Jul 08, 2019
Hundreds of sharks and rays have become tangled in plastic waste in the world's oceans, new research shows.

Strange. I can't think of any plastic waste that would entangle sharks. Oh wait, they were talking about discarded fishing nets. So ultimately there is no "solution" because fishing nets aren't going away and they accidentally wash overboard all the time. Far more sharks and sea mammals are killed in nets while hauling in their catch than in discarded nets. Thank you for bringing our attention to a minuscule problem.


Consider those plastic rings that wrap around 6-pack bottles of soda or beer. In the ocean those plastic rings are too small for large fish and mammals to come through, but little fry are often caught in those rings and can't get themselves out of the ring. The further they go into it, the tighter it gets. So it's also food fish that get caught and die.

Jul 08, 2019
Eating Dairy products depends on cows, sheep,
Surveillance_Egg_Unit

"sheep"? I haven't been consuming any sheep dairy products. In any case, your point is...?

...cows, sheep and other grass eaters whose milk is forcibly taken and consumed by humans such as you, where that milk is made in the cows' udders to feed their calves.
So first, in your earlier post, you strongly imply we should continue to consume meat and thus you apparently don't think it is cruel to kill animals for meat (and I am not saying its necessarily cruel to do that because it isn't and that was never part of my argument) and now you are making out we shouldn't eat dairy products because it is cruel to consume dairy products because milk should be for the baby calves even though farm cows are bred to produce far more milk than can be all fed to their calves? So its not cruel to kill the animals but its cruel to milk them? Have you ever eaten or are still eating dairy products?

Jul 08, 2019
LOL I didn't imply that YOU eat sheep or drink sheep's milk.
Anyone who wishes to eat meat and/or drink milk from cows, etc are free to do so. I have no power over food consumption.
Why would you think that I've said it's cruel to milk cows? If the cows make more milk than the needs of their babies, then all well and good. Killing animals for food has been going on for a million years or so. And those that weren't killed by humans, were killed by wild animals such as lions. Which kind of killing do you consider more cruel? Both humans and lions have to eat. But humans slaughter steers far more humanely without much pain or any cruelty. Which is preferable to you?

Jul 08, 2019
Have you ever seen a documentary of a pride of lions taking down a gazelle or a baby elephant? To me, it is one of the most horrendous things to happen in Nature. The look of fear in their eyes is something that is breath-taking. Humans also get eaten by lions sometimes. That's even worse.
So there IS a huge difference between being mauled and killed by a lion or tiger, and a steer being put into a chute and a hammer knocks him out and it is instantly killed. It happens quickly, whereas a lion killing a man or a zebra is a slow and painful death. Which do you prefer?

Jul 08, 2019
SEU

There's nothing wrong with eating meat but even having a one meatless day a week makes a big impact. I at least try to do it every week just for to sake of it but sometimes I'm just too lazy. Vegetarian food takes much more effort to make. I think all humans should think more about what they eat. Everything is mass produced and all the slaughtering happens behind closed doors. Would be nice to see how many people would convert to vegetarians if one would still need to slaughter his own food. Much easier to get a steak from the supermarket than raise an animal, take care of it, kill it and then eat it. So easy that we don't value meat as much as we should.

There's also easy ways to reduce plastic. I would start with the endless amounts of plastic bags. In reality, one only needs a few plastic bags a year. There could be a global "plastic tax" little bit like emission trading. You would to need to pay more for making unrecyclable plastic products and so on.

Jul 08, 2019
SEU
It's not a plastic tax that is needed
we need to use paper and cardboard instead of plastic
because
a tax does not prevent you from packaging in plastic as the tax is passed on to yourself as the customer

Jul 08, 2019
SEU
It's not a plastic tax that is needed
we need to use paper and cardboard instead of plastic
because
a tax does not prevent you from packaging in plastic as the tax is passed on to yourself as the customer

Do you understand how the emission trading system works? In this case, companies that make plastic would pay a tax according to how environmentally good their plastic is. Bioplastic that is recyclable would pay the least amount of tax etc. Yes, the prices would pass to the customer prices but it would still only promote the use of better plastic.

I agree on using more cardboard and paper but it's not possible to eliminate plastic completely. At least not yet.

Jul 08, 2019
Customers would do business with places that don't use plastic and avoid goods packaged in it because they cost more. That's what the tax is for.

This is economics 101.

Jul 08, 2019
Plastic Tax all at sea

The inland revenues dream come true - plastic tax
what does not contain plastic
biros, mobiles, tablets, steering wheels, backpacks, suit cases, kettles to infinity and beyond
for as we loosen the plastic buttons on our shirt collars with the sweat of the tax inspectors breathing down our necks
for even the environmentally sensibly recycled plastic will be taxed

Then when a safe alternative is found
the inland revenue has now spent the money, so will raise a new tax to replace the plastic tax

When the problem was never the plastic in the first place - it was dumping the plastic in the sea

Jul 08, 2019
Try to get that through your thick Nazi skull, you ugly fat dingaling nut job
You're a fake. Under multiple socks. For years.

Leave.

Jul 08, 2019
Try to get that through your thick Nazi skull, you ugly fat dingaling nut job
You're a fake. Under multiple socks. For years.

Leave.
says the ugly fat dingaling nut job Nazi arsehole

You have never showed any of us the proof that I've ever made sox. But we all know that YOU are the king of making sock puppies to pretend that you're someone else and to make fun of others. You seem to forget that all of your personas can be found very easily just by googling it. So you're a LIAR. And we will come for you when your heart stops and your life ends. We will be there when it happens and you will not get away from us. I promise you that, Otto.

Jul 09, 2019
Plastic Tax all at sea

The inland revenues dream come true - plastic tax
what does not contain plastic
biros, mobiles, tablets, steering wheels, backpacks, suit cases, kettles to infinity and beyond
for as we loosen the plastic buttons on our shirt collars with the sweat of the tax inspectors breathing down our necks
for even the environmentally sensibly recycled plastic will be taxed

Then when a safe alternative is found
the inland revenue has now spent the money, so will raise a new tax to replace the plastic tax

When the problem was never the plastic in the first place - it was dumping the plastic in the sea

If you can find a way to tax only the plastic that goes in to the sea, I'll take that too. The tax should not be much of a revenue for anybody as it should be spend on cleaning the plastic waste and stopping the harm.

Jul 09, 2019
Plastic Tax all at sea
cortezz
If you can find a way to tax only the plastic that goes in to the sea, I'll take that too. The tax should not be much of a revenue for anybody as it should be spend on cleaning the plastic waste and stopping the harm.

if it is an offence to dump plastic in the sea as this article patently demonstrates
you cannot tax a criminal offence
as that legitimises it
you can impose a fine but you cannot tax it

Jul 09, 2019
The principal problem is low-density plastics, though even high-density ones can cause problems like the one shown in this article. The low-density plastics are the ones that need to be taxed.

Jul 09, 2019
And we will come for you when your heart stops and your life ends. We will be there when it happens and you will not get away from us. I promise you that, Otto
Personal threats physorg? That enough for a ban??

Granville
Rrwillsj
SEU

-block them and keep them blocked. Recommend this in every thread.

Jul 09, 2019
Micro-plastic
Da Schneib
The principal problem is low-density plastics, though even high-density ones can cause problems like the one shown in this article. The low-density plastics are the ones that need to be taxed.

Are plastic string orange string bags recyclable
like a lot of plastic, plastic waste is getting to small to see
string bags break into tiny little bits like dust
blowing in wind and the sea
Milk cartons can be dealt with, but not micro or nano particles


Jul 10, 2019
Micro-plastic
Da Schneib
The principal problem is low-density plastics, though even high-density ones can cause problems like the one shown in this article. The low-density plastics are the ones that need to be taxed.

Are plastic string orange string bags recyclable
like a lot of plastic, plastic waste is getting to small to see
string bags break into tiny little bits like dust
blowing in wind and the sea
Milk cartons can be dealt with, but not micro or nano particles


We've noticed that those thin plastic grocery bags begin to tear easily and crumble if left in the sunlight. Not so much with hard plastics. But supermarkets in the US accept old used thin plastic grocery bags, but they don't want any type of plastic food wrap or plastic food bags. We collect and return them anyway to do what they want with them.
We also recycle hard thick plastics after removing paper from their surface. But it's annoying to roll the paper off and the glue still adheres to it.

Jul 10, 2019
Plastic Tax is not the Answer

The Answer is this Plastic
SEU> We've noticed that those thin plastic grocery bags begin to tear easily and crumble if left in the sunlight

A paper string bag is the answer
Because these oranges come in large cardboard boxes from the fruit packers
Another example, Bananas
BANANAS are perfect examples of environmental packing
We put them in our trolley naked in the altogether without a thought
Bananas are probably the only product we select a nice ripe bunch and put it our trolley
BANANAS are a lesson to us all for plastic free packing
As the best thing of all
No Plastic Tax can be applied to this BANANAS skin

Jul 10, 2019
Other fruits such as pears, berries, grapes, cherries don't have to be peeled. Some of the nutrients are IN the skin. I seem to recall that a tarantula was found in a shipment of bananas from Mexico one day. I have no idea what they did with it.
There was a pet store that we had frequented awhile back where the owner had a pet tarantula. Big and hairy, it was. And as fat and ugly as Otto. But the tarantula couldn't help it. It was quite docile and the glass aquarium it was kept in was clean. I remember that their grocery bags were of thick paper.

Jul 10, 2019
Here in Finland supermarkets have started to sell reusable plastic fruit bags. They are very durable and it has a string system to close it properly. Only tough thing is to remember to take it with you to store. They should just put more price on the standard plastic bags and people would remember to bring their own with them.

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