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10 Things to Know About - Season 11 Episode 4 -
Invasive Species
Invasive Species
Category
😹
FunTranscript
00:00Why are we so resistant to change and what can we do to challenge the status quo?
00:06And how do invasive species threaten nature and their way of life?
00:10We'll be looking into all this and more on 10 Things to Know About.
00:21This week, we're looking into some of the invasive species that threaten our biodiversity
00:26and checking out the latest monitoring technologies aimed at keeping them out.
00:44Invasive species can be found anywhere, but one pest in particular has been a cause of great concern for experts lately.
00:50A single Asian hornet was first spotted in Ireland back in 2021,
00:54but earlier this year, a fully developed nest was found in Cork City,
00:58with a second nest being found a couple of weeks later.
01:01So just what are these dangerous invaders that we've been hearing about so much lately
01:05and what can be done to curb their threat?
01:09Aidan O'Hanna was part of the task force, led by the National Parks and Wildlife Service,
01:14that investigated the Asian hornets that were found in Cork.
01:17As the name suggests, it's native to Asia, so it lives in China, Vietnam, parts of India.
01:22We know that they can spread very fast when they're introduced beyond their native range.
01:26So this species, for example, was introduced into France about 20 years ago,
01:30and it has spread like wildfire around Europe ever since.
01:33It's now got a foothold in southern England, and we've had two nests in Ireland this summer.
01:37Why are we worried about them being here?
01:39They're predators of other insects.
01:40So imagine them in the insect food chain.
01:43They're kind of bigger than our other wasps, so no other insects are going to eat them,
01:47and they feed other insects to their young.
01:49So they could have damaging effects on our pollinator populations.
01:54Asian hornets are a significant threat to Ireland's honeybees.
01:57A single hornet can kill and eat up to 50 honeybees a day,
02:01and each nest can house around 6,000 hornets.
02:04So studying the nests discovered in Cork is an important step in understanding
02:09and tackling their establishment in the future.
02:16This is bits of that that we're seeing here in front of us.
02:18This is a section of one of them, yeah.
02:19So this nest was taken from Cove.
02:22So it's a small enough nest.
02:23This one has been dissected out to study the nest demographics
02:26and population size and to take samples for future DNA work as well.
02:31As far as wasp nests go, you can actually identify the nest.
02:33They have a different architecture.
02:35So our native wasps have this kind of like,
02:37they have these straight lines of carton that they build around it, and they're grey.
02:41Thankfully, Asian hornet nests are sort of this orangey-browny-yellow colour.
02:46Like most insects, they go through a complete metamorphosis,
02:48so they start off life as an egg, and then they spin a cocoon,
02:51so that's what these silk caps are, yeah.
02:54And I can actually, I'll open one up here to show you underneath.
02:56You can see there's a larva underneath it.
02:58Oh, yeah.
02:59It'll spend a few weeks in there, and then it will pupate,
03:01so it'll start to grow its legs and its antennae,
03:03and its kind of more recognisable insect head.
03:06The workers are female.
03:07They're more valuable because they're the ones that help propagate the nest
03:10and feed new workers and tend the eggs and so on.
03:13Males are unfertilised, and they're only just used for mating in kind of late summer.
03:17Having the larvae will tell us two things.
03:18It'll just help to have extra specimens for DNA analysis,
03:22but also we cut them in time, and we'll be able to examine their gut contents
03:25and see what species of Irish insect they're being fed.
03:28Another trick to help that as well is as the larvae grow,
03:31so before they spin these cocoons,
03:33their entire gut contents get emptied into the cells called meconium,
03:37and the meconium is basically, it's a record of everything they've ever eaten.
03:40Does doing that kind of analysis allow us to see
03:42what the potential threat of these insects are to Irish species?
03:46Yes.
03:47I expect that the honeybees will feature very strongly in these nests.
03:49I was in the field one or two days,
03:51and certainly we saw them carry off a honeybee,
03:53so honeybees would come to the bait station
03:55and the hornet would just pick them up and fly off with them,
03:57and we saw them attack wasps as well and green bottle flies.
04:02There were two Asian hornet nests found in Cork this summer,
04:06and Aidan is about to give me a fascinating and slightly scary insight
04:10into the complex structure of the much larger and intact one.
04:14So, this is the big one.
04:16This would be a mask situation
04:18because it's way more fresh than the other one,
04:21and it's in order of age,
04:45so these later ones are brand new.
04:47They tend to be in older nests,
04:48the ones where they produce males and future queens
04:51from these newer parts.
04:52At the moment, you can see there's nothing in them,
04:54just eggs,
04:54which tells us that this is a mature colony,
04:56but it wasn't yet at the stage
04:58that it was producing males and future queens.
05:00You can see cocoons,
05:01and some of the cocoons,
05:02you can see there's actually adults ready to emerge.
05:08Terrifying.
05:08There you go.
05:09And so this is a female.
05:10It's a worker.
05:12It's cool.
05:12It's like a factory for wasps.
05:27By analysing the nest structure,
05:29the insect's eating habits,
05:30and their DNA profile,
05:32scientists can build a picture
05:33of where the hornets came from
05:35and what their potential impacts might be.
05:37This information can help our agencies
05:41plan a strategy for the years ahead
05:43and better inform and alert the public
05:45on what to be on the lookout for.
05:48And so is there anything that we can do
05:50to stop species like the Asian hornet
05:52from becoming established here?
05:53We can probably never stop them
05:54from being introduced.
05:56Just the way trade works,
05:57I mean, trade isn't going to slow down
05:58between Britain and Ireland.
05:59There's goods and services
06:00and people moving all the time,
06:02and these are tiny wasps.
06:03They can hitchhike in the back of a car
06:04on a pallet of food.
06:06A British colleague was telling us
06:07that somebody had a cabbage
06:08from France in England
06:09and they went to cut it open
06:10and a hornet crawled out of it.
06:12So they're really good at hiding.
06:13The best way to stop them
06:14from getting established in Ireland
06:15is to detect them early.
06:17That's what happened here
06:18and it was really great
06:19that we have something
06:20like the invasive species alerts
06:21with the National Biodiversity Data Centre.
06:23It's great that we have a public
06:24that are clued in enough
06:25to spots that something
06:26looks a little bit weird
06:27and they can take a photo of it
06:28and upload it,
06:29and then nerds like me
06:30can then help identify it
06:32and the National Parks and Wildlife
06:33service will kick in a response
06:35to then track down
06:35and find the nest.
06:50One of the biggest problems
06:52that invasive species cause
06:53is the damage
06:54and destruction of crops.
06:56And one of the worst offenders
06:57across Europe
06:58is the stink bug.
07:00It doesn't look like much,
07:01but don't be fooled.
07:03It poses a serious threat
07:04to agriculture
07:05across the continent.
07:07Thankfully,
07:08the stink bug
07:08hasn't landed in Ireland yet
07:10and scientists
07:11like Michael Gaffney
07:12are working hard
07:12to keep our crops safe
07:14from these smelly invaders.
07:17At the moment,
07:18it's estimated
07:18that it can attack
07:19about 300 different types
07:20of plants
07:21from about 48 different families.
07:23So from an agricultural perspective,
07:24you're talking about palm fruit,
07:26so your apples and pears,
07:27you're talking about
07:28saw fruit,
07:29raspberries and blueberries.
07:30It can attack tomatoes,
07:31it can attack potatoes,
07:33brassicas,
07:33it can also attack
07:34a wide range of trees.
07:35So things like ash,
07:36maple, sorbis,
07:37even buddlia.
07:38This is a brown marmorated
07:39stink bug.
07:40Called marmorated
07:41because if you notice
07:42on the edge of its body,
07:44it has little white flecks
07:45and brown,
07:46so it gives that kind
07:47of variegated look.
07:49And they kind of look
07:49like a green shield bug
07:51that you find in your garden,
07:52but where does
07:53the stink part of it come?
07:54So the stink part
07:55comes from scent glands
07:56and when they get disturbed,
07:58when they get frightened,
08:00they release this scent.
08:01They also use the scent
08:02to attract other individuals,
08:04other stink bugs.
08:05And then if they gather
08:06together in your house,
08:07then it's a real problem.
08:08Yes,
08:09and you disturb them particularly,
08:10you can get quite
08:11a bad pungent odour
08:12and you then at that stage
08:13do have to remove them
08:14or preferably have someone else
08:16remove them for you.
08:17But the good news is
08:18they're not in Ireland yet.
08:19They're not in Ireland yet.
08:20Its natural territory
08:21is around Japan,
08:22Korea and China.
08:24In the last 30 years,
08:26it has significantly
08:27expanded its range,
08:28mostly because of its habit
08:30of hitchhiking
08:31into shipping containers
08:32and into vehicles
08:33and other forms of transport.
08:35Last year in 2024,
08:36they did find the juvenile stages,
08:38the nymphs in the wild in Britain.
08:40So that would be again
08:41an indicator that there's
08:42the potential that the pest
08:43is becoming maybe established
08:44in that country,
08:45which then has implications
08:46obviously for Ireland.
08:51To monitor both native
08:59and invasive pests,
09:01farmers currently use
09:02simple sticky traps.
09:04They hang them in their fields
09:05then check to see
09:06what insects have been caught
09:07before assessing if and how
09:09they might need to take action.
09:11Michael shows me this example
09:12of stink bugs caught
09:13on a sticky trap in Italy.
09:15It is a real challenge
09:18to monitor effectively.
09:19It's time consuming.
09:20You need a fair bit of knowledge
09:22to identify the traps.
09:23Often the traps are,
09:24as I say,
09:24are even fuller than this
09:25so it can take quite a bit
09:26of time to go through it.
09:27So we felt that to speed it up
09:29we needed some sort of
09:30automated system.
09:31Even initially to take pictures
09:32but then as the project developed
09:33we discovered that actually
09:34we could use artificial intelligence
09:36and machine learning
09:38to actually help
09:38with the identification
09:39of the insects on the trap.
09:41The technological expertise
09:43to help identify
09:45these troublesome bugs
09:46is being developed
09:47by a team of researchers
09:48at Tyndall National Institute
09:49led by Brendan O'Flynn.
09:52Computers and artificial intelligence
09:54are great at some things.
09:56One of the things
09:56that they're good at
09:57is looking at images
09:58and seeing very, very small
10:00subtle differences
10:01between a wide variety
10:02up to millions of images.
10:04And we were able to provide
10:06our system that we've developed
10:07with that training data set
10:09to help them understand
10:11what is a brown marmorated stink bug
10:13and what isn't.
10:14So how does it work?
10:15So typically this system
10:16will be deployed
10:17to operate autonomously.
10:19It will be battery powered.
10:20The solar panel will charge up
10:22that battery
10:22so it can exist for a long time
10:24in a field
10:25where there is no mains power.
10:28Every dawn and every dusk
10:30this system takes an image
10:31of the two sides of this trap.
10:33And then the algorithm
10:34starts working.
10:35It establishes the regions of interest
10:37so it sees blobs
10:39on the sticky trap
10:40and it understands
10:41that this might be an insect.
10:43But then the artificial intelligence
10:45kicks in
10:45and it looks at those regions
10:46of interest
10:47and understands
10:47which one is actually
10:49a brown marmorated stink bug
10:50and which is not.
10:51Okay, brilliant.
10:52And that's based on
10:53very subtle differences
10:54in terms of antenna,
10:55colour,
10:56carapace shape and size.
10:58You can see where
10:59each brown marmorated stink bug
11:01has been identified correctly
11:02as opposed to being
11:03some random insect
11:04that happens to be stuck
11:05onto the glue trap as well.
11:07So you've just developed
11:09a little built-in
11:10at-home entomologist
11:11in this little system.
11:11Effectively,
11:12it gives the farmers
11:13the capability
11:14to make decisions
11:15on their farms
11:16that previously
11:17they would have needed
11:18an entomologist
11:18to help them.
11:19Yeah.
11:29And this is a prototype.
11:31You're developing it
11:32all the time
11:32and not just teaching
11:33the algorithm
11:34about what a stink bug looks
11:35but actually working out
11:37the best way of it
11:37functioning in the field.
11:39Absolutely.
11:39It's a big challenge
11:40taking technology
11:41like we're developing
11:42out of the lab
11:43and into the real world
11:44because it's the unknown unknowns
11:45that you have to encounter then.
11:47So we've developed
11:48a second iteration
11:48of this system
11:49where we've stripped out
11:50the mechanical component
11:51in terms of the motor.
11:53We've integrated
11:54the improved algorithms
11:55but it's a far simpler system
11:57to deploy
11:58and it's a far simpler system
11:59to maintain
12:00and this is really important
12:01from a cost perspective
12:02because the farmers
12:03have a very narrow margin
12:04to operate in
12:05and reducing the maintenance costs
12:07and the maintenance cycle
12:08with these sort of systems
12:08is really important.
12:09I love the idea
12:10that you're trying to make
12:11something that's quite
12:12very cutting edge
12:13but like as cheaply
12:14and as deployably
12:15as possible
12:16as accessible as possible.
12:18Yeah.
12:18So we designed this
12:19specifically to be simple
12:20but there's a lot
12:21of background engineering
12:22and science
12:23that has gone into
12:24the development
12:24of this prototype.
12:25There's mechanical engineering,
12:273D printing,
12:28electrical engineering,
12:29the edge analytics
12:30and machine learning
12:31obviously
12:32and the embedded systems
12:33programming of the microcontrollers.
12:35So it's a very
12:35multidisciplinary team
12:36that has developed
12:37this quality prototype system
12:39for deployment.
12:41The hope is the future
12:42is that we can develop
12:43systems like this
12:44that can do multiple insects,
12:46that can monitor your aphids,
12:47your thrips,
12:48your common pests,
12:49not just invasive species.
12:51Because the trap
12:52can run on batteries
12:53and can almost run
12:54relatively independent,
12:55it could be deployed
12:56in forests,
12:57hard to reach areas,
12:58it could potentially
12:59be deployed in ports
13:00and places like that.
13:01Places where you may have
13:02shipping containers
13:03and other things coming in
13:03that might have
13:04invasive pests on it.
13:08This system shows
13:09how technology
13:10and AI can play
13:11a crucial role
13:12in protecting our food systems
13:14and biodiversity.
13:15I'm glad to say
13:16I don't know
13:16what a stink bug smells like
13:18and I really hope
13:19that we can keep it that way.
13:29I'm glad to see that.
13:33I'm glad to be here.
13:46It's a huge thing that I love
13:47for you.
13:48I'm glad to see you.
13:49Australia is a long way from here, and sometimes home comforts can make all the difference.
14:08So thought an English landowner in the 1800s who introduced rabbits for sport,
14:13leading to a cascade of unintended consequences.
14:17Quickly, the rabbits began to multiply, like, well, rabbits,
14:22and a huge rabbit-proof fence was built in a vain attempt to keep them from damaging crops.
14:29Fast forward to the 1930s, and many ex-World War I soldiers had moved to Western Australia to farm.
14:37But when drought struck, the native emu came through the wheat fields,
14:41and being over six foot tall, the emus made light work of the rabbit-proof fence.
14:48Desperate times called for desperate measures.
14:51The former soldiers called in the current army.
14:54The Great Emu War had begun.
14:58Arriving at a rural outpost, an army unit unpacked machine guns and unloaded on the emus.
15:04Now, emus, being master tacticians, do two things.
15:09Scatter and run really fast.
15:12So fleet of foot is this flightless bird, that even machine guns mounted on trucks were too slow.
15:18And after much mockery of its methods by the opposition in Parliament, the government called it off.
15:24The emus, unaware that they were even fighting a battle, had won the war.
15:28From the invasive introduction of brazen bunnies to the military misstep of machine gunning a national symbol,
15:37the beloved emu population remains stable and in peacetime to this day.
15:42See you next time.
15:43It's a long way from the largest lake in the world, to the largest lake here on the island of Ireland.
16:02But that's the distance that the zebra mussel has travelled to set up home here in Loch Ney.
16:07And this invasive mollusk is creating serious problems for this vital local resource and its ecosystem.
16:15I'm on the shores of the Loch to meet Caroline Murphy, who carries out research on water pollutants and biohazards.
16:23Caroline, can you tell me why Loch Ney, aside from being very beautiful, is so important?
16:29It's the largest lake in both UK and Ireland.
16:31It takes 47% of the water from Northern Ireland.
16:37The water flows in from six different lakes and then it's also used as drinking water for 40% of Belfast.
16:44So it's hugely important, as well as the natural beauty.
16:48There's huge biodiversity here with ducks and a lot of migratory birds come and nest in Loch Ney during the summer.
16:55The concern here at Loch Ney at the moment is the arrival of the invasive zebra mussel.
17:01It originally came from the Caspian Sea and the Black Sea and it has overrun and taken over from the native freshwater mussel here.
17:11Those zebra mussels are the shells that we're seeing all around the place.
17:15Yes.
17:15There's an awful lot of them.
17:17Yeah, quite a bit.
17:18Yeah, they're much smaller than the native freshwater mussel, but they're everywhere.
17:24And it has caused an awful lot of damage.
17:27What it has done, it has filtered the water here in Loch Ney and clarified it so much that the sunlight can penetrate now much deeper down into the water column.
17:37And this has done two things.
17:39It's brought extra sunlight and warmed up the water.
17:41And that, in combination with intensive agriculture in the area, climate change, more flooding, has meant that there's been a tipping point for the production of algal blooms and some of these algal blooms are harmful.
17:55The first recorded appearance of toxic algae in Loch Ney was back in the 1970s, but the blooms have been a major concern since 2023.
18:06We're heading out into the loch to get a better view of the problem.
18:09This is incredibly visually striking.
18:18I mean, I was not expecting it to be so dense.
18:20Yes.
18:21An unprecedented algal bloom.
18:23It's so vast and it's stretching across the lake as far as we can see.
18:28The important thing about this as well is to note that there can be a few different types of algae.
18:32Not all of them are toxic, but it's important for us to be able to detect whether there are some toxic species present.
18:40Okay.
18:40And when you say toxic, what makes these algae toxic?
18:44They can produce a lot of different toxins.
18:47Microcystin, ILR.
18:49It's the most toxic and most ubiquitous, so it's the most common.
18:53It's not known fully what impact the toxins have on the lake because they don't seem to impact on the fish,
18:59but they are very harmful for humans and for pets.
19:03It can cause nausea, diarrhea, vomiting, and it's a hepatotoxin, so it targets the liver.
19:11So if you were consuming the water over a long time, it would damage your liver.
19:14While the green algae is clearly visible to the eye, it's important to determine whether toxic microcystin is present within the algae.
19:34And the team at DCU have developed an antibody-based test that can be carried out on site to detect small amounts of the toxin in the water.
19:42To show me how the test works, Caroline collects a series of samples from the lake.
19:48She lets the algae settle, filters out any debris, and adds each water sample to a tray with a special antibody.
19:56Paul Leonard is part of a research team developing the test.
19:59At current methods, if you want to do this now, we have to take a water sample, put it in a van, and bring it to a lab, and it takes days.
20:08It's very expensive, requires highly skilled people.
20:11It means that you get very few tests.
20:13But if you wanted to monitor it continuously over the spring, summer months when these blooms can happen, you want me to do multiple testing.
20:19If the toxin is present in the water sample, the antibody reacts and changes the colour.
20:25The lighter the colour, the more toxin there is.
20:28As you can see, there's a lot of colour.
20:30It looks complicated, but it's actually not.
20:31It's actually quite simple.
20:33So if you can see here, our colour is very dark, and it gets lighter.
20:36That's because we have a standard curve.
20:37All that means is that we have known concentrations of toxin, and it allows us to have a curve so we can quantify.
20:43Not only do you want to say it's there, we want to know how much is there.
20:46And then we have our water samples.
20:48And we see where we have a very dark colour.
20:50Yes.
20:51That's where there is no toxin in the water.
20:53So this sample here, then, is quite pale looking.
20:56Yeah.
20:57That's our water sample.
20:58Yes.
20:59There is a bit of toxin in the water, then?
21:00Yeah, there is.
21:00Okay.
21:01So that's not great now.
21:02Well, it's what we expected.
21:04Well, with the amount of algae that we saw, I'd be surprised if we didn't, right?
21:07Yes.
21:07Exactly, yeah.
21:07Exactly.
21:08So no swimming here today, then?
21:09No swimming.
21:10Unfortunately.
21:11Presumably, the water that goes to people's houses is treated and is safer, right?
21:15100%.
21:16As it goes through water treatment and process, no, it's 100% safe.
21:21Perfect.
21:22The researchers' next aim is to make the test even more simple and accessible so it can be used by members of the public to test the water in local rivers, lakes, and canals.
21:34Something like your COVID test for water.
21:35Something that you could buy in the supermarket and you can come here and test the water and make sure that it's free to bathe, free to do water sports or allow your pets in and swim as well.
21:46And what we can also see is that since we're here, we want to be able to get that result and have everybody to do the test, the citizen science.
21:54One of the things we can see, if you could detect this with your mobile phone and we could geotag.
21:58So not only can you get the result and know, but we can see the result and go to the local authorities and we can see that there's an algal bloom or there's some toxins in the water being generated.
22:06And so it's a quick alert system.
22:08So I suppose the big point here is that it's almost impossible to stop invasive species.
22:12But what we can do is come up with ways of working out the impacts that they're having and enable us to respond to that and to change our behaviour or to understand what we need to do in response to that changing environment.
22:25Is that fair?
22:25Absolutely.
22:26That's our 10 things to know about invasive species.
22:39Next time we check out the story of carbon and its essential yet highly complex role for all life on Earth.
22:56We'll see you next time.
23:26We'll see you next time.
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