Invasives!

A study has revealed that, since the mid 1970s, invasive species of animals and plants have cost the UK economy at least £5bn (https://www.theguardian.com/environment/2021/jul/29/invasive-species-have-cost-the-uk-at-least-5bn-since-1970s-study-reveals-aoe). The invasives can alter entire ecosystems, endangering native species. Some can also cause structural damage to buildings, clog waterways, kill lots of native trees and ruin crops. The three most costly species are thought to be the European rabbit, Japanese knotweed and the Rock pigeon. Worryingly, we only have good information on the financial costs of 42 of the current 520 UK invasives. Some, like Japanese knotweed and the Grey squirrel, were introduced deliberately but others arrive on or in imported goods. Biosecurity is really important. It's not an optional extra.