26th September 2023
Biodiversity loss is not just measured in terms of extinction, but also in loss of numbers within a species. However if the loss of numbers takes place over years or decades, do we register that it is happening? If we still see butterflies each summer, do we necessarily twig that their numbers have been greatly diminished? How few do we need to see, before we begin to worry?
The Big Butterfly Count data over the last 13 years reveals numbers of the once ubiquitous small tortoiseshell have fallen by 30%, with even larger declines for the speckled wood (-38%), ringlet (-41%), common blue (-44%) and green-veined white (-61%)…[whilst] other species appear to be thriving in an era of big climatic changes, with long-term increases over 13 years for the red admiral (up 78%), painted lady (up 113%), the holly blue (+41%), large white (+27%) and small copper (+66%) – https://www.theguardian.com/environment/2023/sep/15/uk-butterfly-numbers-bounce-back-after-last-years-all-time-low?CMP=Share_iOSApp_Other
By choosing what we grow in our gardens, we can help support butterfly populations. I specifically grow nettles as they provide food and nursery space for the commas’ caterpillars. I try and have plants that are in flower throughout the year – at the moment sedum and the last of the nasturtiums are proving popular for various insects.
For more information on plants and gardening techniques see https://butterfly-conservation.org/how-you-can-help/get-involved/gardening/gardening-for-butterflies
The Green Tau 