In support of this week’s Invasive Non-Native Species Week (15-20 May), we are co-hosting a ‘Push Out the Pennywort’ event to raise awareness of the importance Yorkshire’s inland and marine waterways and the impact invasive species can have upon it.
The event
The event takes place this Saturday, 20 May, at Stanley Ferry on the Aire & Calder Navigation, in Wakefield from 10am until 3pm. Volunteer activities include getting onto the water on a canoe, kayak or paddleboard or working from the side of the bank to help clear the invasive floating pennywort plant. There are also non-physical roles available to help us and our waterways.
Volunteers will need to register attendance in advance before attending on the day. This can be done by completing the survey.
A threat to native plants
Considered the second greatest threat to native plants and wildlife after habitat loss, non-native species damage natural ecosystems. They can also be harmful to humans and interfere with activities on the water – for example, quickly blocking a waterway making it difficult to boat or fish.
We spend around £700,000 every year tackling invasive plants across its 2,000-mile canal network in England & Wales, with the cost to the nation's economy estimated at over £1.7 billion a year.
Floating pennywort is an Invasive Non-Native Species (INNS) from South America, introduced to the UK in the 1980s by the aquatic nursery trade. This attractive, fleshy-stemmed plant grows into floating mats of lush foliage across waterways.
This highly invasive plant is a real problem for inland waterways. It grows very rapidly in warmer summer months, up to 20cm per day, and is responsible for swamping waterways, blocking water flow, crowding out native plants and taking oxygen from fish and insects.
Invasive plants can reduce water quality and habitat availability, having a huge impact on waterways and the native wildlife that live along them. They can also cause damage to historic structures, prevent navigation, and inhibit water control.
British Canoeing, Angling Trust, Environment Agency and Yorkshire Water are working together with us to remove and limit the damage of invasive plants from Yorkshire's inland waters.
A big problem in this country
Environmental project officer Jake Crone, from British Canoeing, is coordinating the project: “Invasive non-native plants such as floating pennywort, giant hogweed, Japanese knotweed, and water fern (azolla) are thriving at the cost of our native plants and wildlife and becoming more and more of a problem across the country, blocking canals, rivers and other waterways.
“With little to no native predators, many invasive plant species outcompete the native plants, as well as being experts at seed dispersal and vegetative reproduction, they travel by any means to get to a new location along the canal or river – meaning it's a constant battle.”
Expensive to move
Stuart Moodie, our heritage and environment manager, said: “Floating pennywort, like Japanese knotweed, can also grow from minuscule fragments. It's incredibly difficult and expensive to remove.
“We have to physically remove the plant from the water often using machinery, which is expensive and time-consuming. Hosting events like this, whereby the pennywort is pushed out of the water onto the banks by non-powered craft is a huge help.”
He added: “Our charity spends a lot of time and money tackling and trying to stay on top of invasive plants along our canals and rivers. These special places are home to a huge variety of animal and plant life, and their delicate ecosystems need to be managed to ensure we have a healthy and diverse plant and wildlife population whilst also protecting our native species.”
