Are invasive species natural? If we introduced them, do we have some responsibility to manage them? What if we could reduce their numbers through the natural process of eating?
In this episode, Jackie Turner (TABLE) joins crayfish trapper Bob Ring to see if we can eat our way out of one of the environmental problems we’ve created - the spread of invasive American Signal Crayfish into the river Thames. We ask if these invasive crayfish are ‘natural’, how they ended up in London’s iconic river in the first place, whether they offer a promising sustainable food source, and why it is so difficult to earn a living doing what Bob Ring sees as an environmentally and ethically beneficial act.
This is the second of a three part series exploring if we can eat our way out of the problems we’ve caused. The last episode featured grasshoppers in Mexico and the next will be on white-tailed deer in forests of the eastern United States.
For more info and resources, visit: https://tabledebates.org/podcast/episode57
Guests
Episode edited and produced by Jackie Turner. Music by William King and Blue dot sessions.
Are invasive species natural? If we introduced them, do we have some responsibility to manage them? What if we could reduce their numbers through the natural process of eating?
In this episode, Jackie Turner (TABLE) joins crayfish trapper Bob Ring to see if we can eat our way out of one of the environmental problems we’ve created - the spread of invasive American Signal Crayfish into the river Thames. We ask if these invasive crayfish are ‘natural’, how they ended up in London’s iconic river in the first place, whether they offer a promising sustainable food source, and why it is so difficult to earn a living doing what Bob Ring sees as an environmentally and ethically beneficial act.
This is the second of a three part series exploring if we can eat our way out of the problems we’ve caused. The last episode featured grasshoppers in Mexico and the next will be on white-tailed deer in forests of the eastern United States.
For more info and resources, visit: https://tabledebates.org/podcast/episode57
Guests
Episode edited and produced by Jackie Turner. Music by William King and Blue dot sessions.
Matthew
The river Thames runs through London. It’s the center of many postcard photos of the city. Today its banks are filled with locals and tourists in busy shops and restaurants. In the past it served as crucial transport for imports and food entering and exiting the city. In this episode we turn to one unexpected culinary contribution that the river offers to today’s food system: invasive crayfish.
Welcome to Feed, a food systems podcast presented by TABLE. I’m Matthew Kessler.
We are continuing our series asking if we can eat our way of a particular problem. Can we introduce something delicious to our plates while at the same time taking care of the surrounding ecosystems?
In a second I’ll turn the microphone over to my colleague at TABLE Jackie Turner, who will tell the story of how the invasive American Signal Crayfish ended up in the river Thames, and whether eating it is a promising solution.
To get to the bottom of this, Jackie spoke to Bob Ring, a crayfish trapper operating in Southeast England. Bob started his business more than a decade ago, seeing an opportunity to help the environment, which he cares deeply about, and to make a profit. Along his journey, Bob has found some unexpected common ground with some of the people he’s sold crayfish to.
Bob Ring
I’ve had various vegetarians say to me: of all the reasons why they were a vegetarian, none of the reasons stopped them in theory from eating the crayfish. They’re an invasive species, they’ve gotta be killed by law, they weren’t farmed, you know, we need to get rid of them.
[music]
Jackie
I think there are lots of people who would describe themselves as having convictions about nature and how best to protect it. Bob Ring, who you just heard from, got into crayfish trapping as a way to remove invasive species from threatened waterways. But the thing about fishing around in muddy waters is, other things end up tangled in your net.
[music]
Jackie
I meet Bob Ring outside an ASDA in South London where he’s just picked up some breakfast.
You got two hash browns?
Bob
Yeah, I tend to live on discounts. I figure it saves me about a good hundred pound a week. I would think, something like that, you know. I might be…
Jackie
I’ve known Bob for years but this is our first time meeting in person. Ever since I found out that there was a man who called himself Crayfish Bob trapping invasive crustaceans in London’s waterways and selling them to restaurants, I knew I had to meet him.
But after years and many hours of phone calls, if there’s one thing I’ve learned chasing this story, it’s that, much like the waterways Bob navigates, the rules that govern what is natural or native and what can be done with it—it gets murky quick.
[car door slam]
Bob
Alright, alright.
Jackie
Bob and I walk to his car where he pulls a binder out of the back seat, and it’s as thick as an encyclopedia.
What are we looking at here?
Bob
This is my—This is some of the laws. I carry them around with me.
Jackie
Bob is obsessed—and reasonably so— with the regulations that govern the trapping of crayfish.
Bob
This is your application for a trap license. It used to be, it was just for a trap. According to this, you know you’ve got to apply to take a crayfish out with your hand. Well according to that also, you have to put a little tag license on either hand and apply for two or one. It’s very petty, I’m inclined to apply for three hands. [chuckles]
Jackie
In his binder, Bob has a list of the invasive species of the UK.
Bob [reading]
“There are 23 animals and 14 plants on the list of Union concern.” Grey squirrel, fox squirrel—well, that’s not a widespread one. There’s the signal crayfish. The virile crayfish
[phone rings]
Jackie
While we’re talking, Bob gets a call.
Bob
Let me just find out—[answers the phone] Hello?
Voice on the phone:
Hello. Can I know if you have any crayfish for sale?
Bob
No, I’m sorry, I don’t at the moment. Where are you?
Voice on the phone
Leeds.
Bob
Leeds. Yeah, I can’t help you up there, I’m afraid. Yeah, I’m sorry. Thank you. Buh-bye. [hangs up] I mean, I could, but it’s such a hassle. That goes off all day bloody long, right? Ok?
Jackie
And it just starts like that “do you have any crayfish for sale?”
Bob
Yeah. That’s it. Have you got any crayfish for sale. “At the moment, no” I said, although we’ve got tanks full of ‘em. And where are you? “Leeds.” Well, you know, where that’s going to go is me having to explain that I’m sorry I can’t do them live, without bothering to go into—well, I could if they were Turkish but they’re hard to get—so I can’t do any live.
Jackie
What Bob is referencing here is that he can catch a species of crayfish called Turkish crayfish that aren’t native but also aren’t on that official list we were just looking at, which means different rules apply to them that allow him to transport them live. This is all in the binder of rules that lives in Bob’s backseat.
Bob has agreed to take me with him to a lake in South London to show me how crayfish trapping works. On the way, he fills me in on the history of how non-native crayfish species arrived in the UK.
The story actually starts in Sweden, where crayfish are a popular delicacy, especially in the summer months. Originally, Sweden had a native population of crayfish that satisfied this craving—a species called the noble crayfish—but these crayfish started dying out from a crayfish plague, so in the 1960s Sweden introduced the American signal crayfish.
Bob
“And the great news is, unlike our noble crayfish species,” said the Swedes, “these things are immune to the crayfish plague. So, hey, let’s get some and put them in our waters.” Which they did, and so they had them all over Sweden, and then they persuaded the British government to bring some over here to farm.
Jackie
That’s right. The Swedish government actually talked the British government into introducing an American crayfish species to be farmed in the UK so that they could be exported to Sweden. Like so many intentional non-native species introductions, this probably goes in the direction you’d expect.
Bob
Soon after they came over in 1976, somebody realised, “hang on a minute, they’re immune to the plague, but they carry it.” So they basically, in Sweden and over here, introduced a whole load of plague-carrying crayfish to our waters, which of course therefore wipe out the non-American species, like the white-clawed that’s here and like the Turkish crayfish, basically.
Jackie
The white claw crayfish is the native crayfish species that is rapidly disappearing from the UK, from a combination of habitat loss, disease and being outcompeted by the American signal crayfish.
Bob
And there’s always an argument that says, well, fine, it’s all natural, people bringing things and plunking them around and everything we do as humans is nature and everything, you know, and all of this, well, us trying to control it is nature as well actually.
Jackie
And this is really what drew me to Bob’s work in the first place, these questions of nature and our place in it. Are invasive species natural? If we introduce them, do we have some responsibility to manage them? What if we could reduce their numbers through the natural process of eating? Should we? But more on that later. We’ve arrived at the lake.
Bob
So, Jackie, what we’re going to do, if you can help me with that one, we’re going through whatever traps we’ve got. I’ve got to check them all for holes, tie bits of string on them, and then discreetly chuck them into the water. We might come across the odd angler. I try and avoid ‘em, because quite often they wanna chat. Other people also always want to chat.
Jackie
We’ve parked on a side street in a suburban neighbourhood. The lake is inside a park, surrounded by an iron fence. Every thirty meters or so there’s a gate that leads to a small wooden platform for anglers to use. It’s a big enough body of water that there are sailboats drifting across it. And the path that goes around the lake is clearly popular with runners and dog walkers.
Bob and I round up his buckets of gear from the car and set off to drop the baited traps in suitable spots along the edge of the lake. We’ll come back on a different day to check them for crayfish.
As we walk around the lake, I am suddenly acutely aware that I had different expectations of what Bob’s life as a trapper in London looked like; this isn’t the Thames, and . . . we’re on foot.
Jackie
You own a boat, right?
Bob
I do, I have several boats, yeah.
Jackie
Where do you keep them?
Bob
Uh, well, there’s a couple at the bottom of lakes . . .
[laughter]
Jackie
You keep them there so they’re safe?
Bob
Yeah, they’re safe, I know where they are. I don’t want anybody to nick it. [laughter] I find that the best way is to sink ‘em.
Jackie
Eventually, we reach the first spot and Bob pulls a trap out of a bucket.
We’re doing this for radio. What does one of these traps look like?
Bob
Ok [laughs], well, there’s these weird engines on the side that there’s sort of steam coming out of them and uh,—nah, they’re sort of a wire coiled thing that spring open into a long cylinder covered in net with holes in either end through which the crayfish are invited to go in when they get a whiff of the delectable bait that we’re chucking in there. And once they’ve gone through the entrance, they find it pretty hard to get out. Unless I’ve left a hole in the trap somewhere, in which care they find it pretty easy. But, I think we’re good. Famous last words.
Jackie
I’m not sure if it’s the smell of the mackerel Bob is using to bait the traps or that we’re at a park where the local birds are used to being fed by humans, but within minutes of arriving, we’re surrounded by the local waterfowl.
Bob
That’s a proper baby coot. Two of them. Right. I’m going to chuck this out that way and hope for the best. Ok, somehow, without falling in the lake, I need to find myself down here to discreetly tie the line off so that the trap doesn’t go missing later.
Jackie
The bank of the lake is thick with foliage so Bob does an amount of climbing through trees and bushes that is perhaps unusual for someone turning 70 next year.
Bob
Sorry, you just have to crash through it, really. You’ll know if it’s anything bad because I’ll start coming up with blood all over my arms.
Jackie
It doesn’t always go smoothly.
[splashing sound]
Bob
Oh bugger! Well, that’s clever, isn’t it? Now I need a stick . . .
Jackie
And with 15 traps to set, it takes a while.
[music]
Jackie
We come back to check the traps on another day.
Bob
So the plan here is literally to grab those buckets out of the back, go around—we’ll start at the very end where we finished—pull in the traps, empty ‘em out, fold ‘em up, stick ‘em in one bucket, and that’s it. Hopefully a decent amount of crayfish in the bucket, put ‘em in the back, take ‘em home, and job done.
Jackie
The first few traps we pull up are empty.
Jackie
A bit unlucky.
Bob
Well, sort of. You never know. Bit strange, to be honest. Because, you know, another time we could have come down and could have expected to get loads of crayfish by now. We got sod-all, really. Expected to have done better than that.
Jackie
A few traps have a couple crayfish in them.
Bob
Oh, we got one! Fantastic.
Jackie
That’s a big one.
Bob
Yeah, bigger anyway. Ok, well, thank you for that, I suppose.
[sound of crayfish scuttling in the bucket]
Jackie
That’s the sound of a crayfish trying to eject itself backwards. In the water they can flip their tails to dart under rocks in the blink of an eye. On land and inside a bucket . . . not so effective.
Crayfish here are bigger than I expected and bigger than the crayfish I grew up seeing in the Great Lakes area of the US. Some of them would fit easily in the palm of my hand and others are as long as my shoe. Bob insists the ones we’re seeing are on the smaller side.
One trap comes up with a dozen or so crayfish in it.
Bob
How many we get in that trap, just like that?
Jackie
That’s a lot.
Bob
Yeah, well relative to what we’ve had in the others, which has been rubbish.
[talking to the crayfish] Come on, you lot. There you go, in there.
[sound of crayfish being dumped and scuttling in the bucket]
Jackie
Bob thinks one of the reasons there are fewer crayfish is that the lake is home to another invasive species that is slowly taking over.
Bob
And the wels catfish, they’ve been introduced to this lake. They love crayfish, for a start. I’ve noticed the population certainly dropped, but the trouble is, eventually, they’ll have every fish and everything in there. It’ll just be a lake full of giant catfish.
Jackie
Like the American signal crayfish, the wels catfish was also introduced to the UK in the 1970s, likely by anglers who admired its ability to grow quickly.
Bob
The anglers love them. Because they get big and because they’re one of the–other than an eel say–the only fish that swims backwards and actually pull backwards. So they love it for the sport.
Jackie
These catfish will eat anything, from crayfish to pigeons to Atlantic salmon. They can grow up to 10 feet long and weigh up to 600 lbs or 270 kilos. But despite being a clearly harmful species to local ecosystems, the wels catfish is not on the list of species that can’t be put back.
Bob
And anglers–there’s lots of them. And they have quite a big influence on the environment agency people, for example. And quite a big influence on government, because there’s so many anglers.
Jackie
I ask Bob if he’s thought of applying the same eat-our-way out approach to catfish that he has to crayfish.
Bob
Will there be a food market for them? Well, possibly. To try and organise that one from scratch would be quite a thing.
Jackie
Ultimately some of the same barriers exist to making a food industry around wels catfish as exist around crayfish. Like crayfish, catfish aren’t popular cuisine here, so it’s a niche food.
Jackie
I asked Bob what he would hope for if he could get investment.
Bob
I mean, I wouldn’t mind having some restaurant sort of hub things, invasive species hub centres across the country where you can bring in and you concentrate exactly on that, on getting rid of the invasive species in the area and doing them up as food. You know, we got the mudjack, got the crayfish, got the squirrel, the Egyptian goose.
Jackie
But one of the biggest flaws in this is obvious, right? How can you build a market around trying to wipe out an invasive species? You might be able to pay back an investment but it’s not a business model that will offer infinite growth opportunities. Bob can see how some companies might invest under some banner of sustainability or environmental awareness but he doesn’t like that either.
Bob
Yeah, it matters to me a lot, I just hate greenwashing, basically. You can see it could go in a really really positive direction. And they love all the sort of eco bit and all of that—except they don’t love it for what it’s all genuinely about. They love it simply for the potential of adding some profit to their business.
Jackie
Bob sees one of his biggest obstacles as the binder of ever-changing laws and regulations that make Bob’s work even harder than tromping through dense foliage all day.
Bob
You try and build up some plans that are based on one principle and a sort of set of laws and things and then they all change, it’s no good at all.
Jackie
Bob wants to trap these invasives. He sees himself as doing a good thing, and wishes the government saw it that way too. But he reckons, although there are some hobbyists out there, he is probably one of only 3 commercial crayfish trappers left in the UK. And the government isn't making his job any easier. The recent laws Bob’s referring to came out in 2019 and since then, a large chunk of his business has shifted to being hired to remove crayfish from private ponds on estates and by angler clubs who don’t want crayfish in their lakes.
But that dream Bob had, of fixing our mistakes by eating these introduced species? It’s getting harder for him to picture it.
[music]
Jackie
A big thanks to Bob Ring for letting me tag along with him. This episode was edited and produced by me, Jackie Turner, with special thanks to Matthew Kessler and Tara Garnett at TABLE, as well as Rose Rimler who listened to an early version of this episode. Music by William King and blue dot sessions. I’m also working on a video about crayfish trapping based on my visits to the lake with Bob that will be out soon; in the meantime, you can find some photos of crayfish, Bob and some hungry-looking waterfowl on our website - tabledebates.org/podcast
Next week, Feed will continue looking into this idea of ‘eating the problems we caused’. Matthew Kessler will be back talking to a conservation biologist about ways to keep the population of white-tailed deer in the forests of the eastern United States in check.