For our team in the Indicators and Assessment Unit (I&A), the 10^th of November was a very exciting day. The latest IUCN Red List update included more than 800 freshwater mollusc species (mainly from Asia, Australasia, South America and Russia). Of these, 1 in 5 species fall within a threatened category which is the first time that we can clearly see this. We also teamed up with Dr Owen Lewis at the University of Oxford to assess a sample of 1500 butterflies, the first 302 of which were published on the latest Red List update. The Red List now includes over 61,900 species assessments and covers a much broader and more diverse range of species than ever before.

(c) Andreas Werth

Freshwater mollusc species are notoriously difficult to study, and this is the principal factor contributing to the high level of data deficiency in some genera. In this update, assessments have been included for several Springsnail (Genus: Leiorhagium) species endemic to the island of New Caledonia in the South Pacific. All of the New Caledonian Springsnail species assessed fall in a threatened category; two species are considered Vulnerable, two are considered Endangered, two are considered Critically Endangered, and one species is Extinct.

So, how did we carry out our mollusc assessments? Firstly, mollusc taxonomy is complicated and we relied on taxonomists’ help for this in order to draw up our species list. Then came the fun part – trawling through the literature to find the data we needed to carry out Red List assessments; namely distribution, ecology, population and threat info. After many visits to the National History Museum’s mollusc library we had sufficient information to present to our species experts. Our Red List workshop (kindly funded by EOL – The Encyclopedia of Life) brought together species experts from across the globe, and freshwater molluscs really were the talk of the IoZ for the week. Workshops such as this one can get quite heated as experts discuss species’ taxonomy and extinction risks. Nevertheless, it then still took a long time to clean up assessments, produce range maps from expert information and check assessment consistency before the species finally appeared on the IUCN Red List yesterday. Needless to say, much chocolate was consumed.

(c) Emily Watson

However, there is still a lot to do, so we cannot rest on our laurels quite yet. For starters, we are currently finalising another 200+ species assessments for freshwater molluscs, so we can get a clearer global picture of how freshwater molluscs and freshwater systems in general are faring. Many more butterflies need assessing, a global assessment of the world’s cephalopods (octopus, squid and cuttlefish) is underway (carried out by Dr Louise Allcock from the National University of Ireland in Galway), and the assessment of 1,500 dung beetles is likely to keep us entertained for the next months to come.

Dr Monika Bohm, Suzanne Offord and Clare Duncan

Zoological Society of London (ZSL)