“SOME OF THESE SPECIES ARE TRULY HORRIBLE, BUT THEY’RE QUITE FASCINATING!”
Meet the scientist tasked with halting the spread of alien plants and animals
MOST anglers will be aware of the perils of unwanted ‘guests’ such as signal crayfish and Himalayan balsam in our fisheries.
But how can we fight back? Emily Smith is a scientist on a mission with the Angling Trust to improve our knowledge and protect fisheries from invasive species, while conducting a PhD study at University College London.
Dom Garnett met the invasive non-native species manager to find out more about some of the UK’s most notorious invaders.
Q How did you first get interested in freshwater and invasive non-native species? They’re not exactly cute or appealing, are they?
Emily Smith: It probably began with my dad, who is an angler and fish farmer. I grew up around water and always found it interesting. Then again, when I began studying freshwater ecology I didn’t imagine I would be looking at life forms that can destroy ecosystems, or ways we can eradicate unwanted species. I guess I’m probably the sort of person who enjoys a horror movie more than a romantic comedy!
Q Do you end up hating these plants and animals even more than the rest of us? Or do you have a strange admiration for them?
ES: I think you get a grudging respect. That said, you still feel absolutely gutted when an outbreak is discovered, because you’re only too aware of what the impact will be. Some of these species are truly horrible, but they’re quite fascinating! The sheer variety of ways they live, spread and become established is amazing. So yes, you hate them but almost admire them at the same time.
Q What’s the nastiest invasive creature in UK waters right now?
ES: For me, it’s the killer shrimp. Unlike other species, these things will kill just for the sake of killing, even when they don’t need to! I remember going to Grafham and pulling up ropes that were absolutely alive with them. Scientific surveys there have been bleak, with virtually all other invertebrates wiped out. I’d never come across that level of devastation before.
Q And as for the weirdest, what are the most baffling cases you’ve come across in this country?
ES: The baby alligator spotted and captured in Chew Valley Lake last year was pretty strange. The piranha at Chichester sewage works takes some beating too. Of course, anything that can be kept by humans is likely to be released at some stage – terrapins are now
quite common in London. Even more bizarrely, goldfish have been found in mountain lakes in the UK where there is no vehicle access of any kind for miles.
Q Talking of fish being deliberately released, a minority of anglers are still doing this in the UK. What would you say to them?
ES: I would definitely advise against it, because you don’t know what the consequences will be. Whether it’s a bottom feeder that will disturb the river or lakebed, or a new predator, the impact could be huge and potentially irreversible. I understand why some people would spread fish that they want to catch, but I’d say travel and enjoy them where they exist naturally.
Q As for all the invasive plants and animals present in the UK, is it possible to eradicate any of them, or is it a case of damage limitation?
ES: In some cases it might be possible to eradicate a species if we find them quickly, but for many established species we don’t yet have the means. Water primrose is currently present at some 33 sites, but now 14 sites have been successfully eradicated and a further 19 are being managed with only small areas of growth remaining.
With many other species, sadly, there is no simple answer. Himalayan balsam, for instance, is subject to ongoing tests to see what eats it, and which diseases, fungi and other means might
work to control it. But this means huge amounts of testing on native species to rule out further impacts. The best answer is to prevent invasive species getting a foothold in the first place!
Q So what should we do if we find invasive species at a fishery?
ES: The simplest answer is to report and log any new sighting immediately. This is really key, as the sooner it is reported, the greater the chance that it could be removed, or stopped from spreading to other waters. Floating pennywort, to take one example, can spread 20cm in a single day.
If it’s a dangerous invasive threat, early reporting could save your fishery or club thousands of pounds. A great way to do this is by taking a photo of the species and uploading a record with its location to iRecord (see panel right). This can be done online, or downloadthe free iRecord app to your phone, which means you can do it there and then. You can do so with the usual Environment Agency number – and this should be as instinctive as you would report poaching or pollution at a fishery. It’s important we all do our bit to help.