4Bs Butterfly & Moth Survey 2024
One of the aims of our 4Bs Biodiversity Park initiative is to demonstrate how a community working together could contribute to studying and understanding biodiversity in our area. The annual Big Butterfly Count organised by Butterfly Conservation https://butterfly-conservation.org/ whose mission is to save butterflies, moths and the environment, provided the ideal opportunity. Between July 15th and August 4th residents of the UK were invited to undertake a 15min survey on a sunny day to count the number of butterflies in a list of 10 species using an App or an identification chart.
The National Picture
Prior to this year’s count in June, there was concern about the lack of butterflies and bees, with many commentators attributing this to the poor spring early summer weather. July witnessed warmer and sunnier weather and butterflies, moths and other pollinators began to appear in greater numbers. By the end of the count (see footnote) 919,325 butterflies and moths of the selected species had been counted across the UK with an average of 7 butterflies recorded for each count. If this figure is correct this is an all time low compared to the previous low of 9 butterflies per count in 2022 and almost half the average number of 12 butterflies recorded for each count in 2023. While we may blame the poor weather for the reduced abundance of these indicator species of butterflies and moths, the long term decline in populations must be a serious cause for concern.
Butterflies & Moths in the 4Bs
Turning to our 4Bs patch (Buckland, Betchworth, Brockham and Box Hill) this is the first time we have tried to collect data for our area so we have nothing to compare. Thanks to the contributions of 54 citizen scientists we managed 176 counts and recorded a total of 2766 butterflies and a total of 32 species (28 species of butterfly + 4 moth).
Species Abundance
Large White n=136, Small White 232, Green Veined White 21, Brimstone 14, Marbled White 71, Small Copper 31, Gatekeeper 609, Meadow Brown 999, Ringlet 69, Speckled Wood 57, Comma 46, Painted Lady 5, Small Tortoishell 5, Red Admiral 35, Peacock 39, Common Blue 137, Holly Blue 2, Silver Y 25, Six Spot Burnet 205, Jersey Tiger 12, Also significant but unknown numbers of Small Skipper and Large Skipper and small but unknown numbers of Small Heath, Dark Green and Silver-washed Fritillary, Small Blue, Chalk Hill Blue, White Admiral and Brown Hairstreak.
Our commonest butterflies and moths are: 1.Meadow Brown 992; 2.Gatekeeper 624; 3.Small White 232; 4.Six Spot Burnet 205; 5.Common Blue 137. This compares with the commonest butterflies and mothsi in the UK-wide survey 1.Gatekeeper 184,901; 2.Meadow Brown 175,654; 3.Large White 135,375; 4.Small White 110,016; 5.Peacock 48,813. These differences are likely to reflect the particular habitats we have within the 4Bs area.
Further work
Thanks to our 54 citizen scientists we now have an excellent data base that provides us with baseline data for future surveys and a map of locations. Using this information we will be able to say something about the distribution of butterflies across the 4Bs area. We can continue adding to this data base outside the count by adding any new species to our list as they are spotted. Furthermore, the Big Butterfly Count interactive map remains open through August for people to continue uploading counts.
We have made a great start to understanding the biodiversity of these indicator species in our area and we need to say a big thank you to everyone who contributed.
Footnote - The numbers above for the 2024 survey are the numbers at 11pm on August 4th. On August 5th butterfly counts are still being accepted so these numbers may rise.
This movie shows the butterfly species we have identified to date. We will add to it as more butterflies are discovered.