News archive

April 2017

Tuesday, 11 April 2017

Non-Native Invasive Species

Non-Native Invasive Species

Andy Thomas tackled one of the main threats to native species all over the world - our habit of introducing plants and animals to new places where they then spread uncontrollably.

As a keen fisherman, his focus was on rivers and wetlands - especially the formidable American Signal Crayfish which poses a massive threat to native species in rivers, lakes and ponds. This six-inch long invader has already annihilated the smaller native White Claw crayfish from most of the waterways in the south of England.
The Signal also digs burrows up to three feet long in river banks - the numbers and size of the burrows is increasingly causing river banks to collapse. This widening of the river bed causes rivers to become more sluggish and affects the ecology and thus, other wildlife.

Andy listed the top ten non-native invasive species in terms of what they cost us to try and control. Number one was the Rabbit! Giant Hogweed and Japanese Knotweed also featured...

We have to hope that stricter measures on controlling imports will help in the future so people won't be tempted to try out that exotic looking plant in their pond or think that frog will sound nice in the garden!

Despite the worrying nature of Andy's talk, his engaging style and quick repartee brought forth many laughs and entertained a well-attended meeting.



Please go to the Events page where this item has a Google Map link to our location at

St Mary's Church (Gwinnell Room)
207 High Road
South Woodford
E18 2PA

We meet on the second Tuesday of most months at 8pm
Our nature talks cost: £3.00 for RSPB & Wren members, £3.50 for non-members, Free to schoolchildren


St Mary's Church is a short distance from the junction with Chelmsford Road. Parking is allowed on the single yellow lines outside in the High Road after 6.30 pm. There is also free parking at Derby Road car park.
It is about a 15 minute walk from South Woodford tube station (on Central line). Buses 179 and W13 stop nearby.



++++++++++++++++++++++++++++++++++++++++++++++++++
If you click on the 'Download file' link, then you will see the striking poster that David (our Publicity officer) has produced to advertise this talk.
We distribute the poster to libraries, supermarkets (many have Community Notice boards) and have managed to get it displayed on some of Redbridge's Community Notice boards (e.g. in Wanstead High Street).

If you have any suggestions of other places to advertise that may encourage more people to come to our talks, we would be glad to hear them.

Please feel free to print off the poster yourselves and help us spread the word!
++++++++++++++++++++++++++++++++++++++++++++++++++

Download file