Invertebrates on the Brink

One fifth of the world’s invertebrates may be heading for extinction, according to ‘Spineless’, a report published by the Zoological Society of London (ZSL), in conjunction with IUCN and the IUCN Species Survival Commission. Digging up earthworms, chasing butterflies and collecting clam shells could become a thing of the past if enough isn’t done to protect invertebrates. And if they disappear, humans could soon follow. These critters form the basis of many of the essential benefits that nature provides; earthworms recycle waste nutrients, coral reefs support a myriad of life forms and bees help pollinate crops.

More than 12,000 invertebrates from the IUCN Red List of Threatened Species were reviewed by conservation scientists who discovered freshwater species to be under the highest risk of extinction, followed closely by terrestrial and marine invertebrates. Dr Louise Allcock of the Ryan Institute at NUI Galway was one of the co-authors of the report.

The findings from this initial group of global, regional and national assessments provide important insight into the overall status of invertebrates. Together they indicate that the threat status of invertebrates is likely very similar to that of vertebrates and plants.

Invertebrates are at risk from a variety of threats. Molluscs such as thick shelled river mussels suffer from pollution from agricultural sources and dam construction, which affects the quality of the water they live in. Crayfish such as the noble crayfish, are at risk from the impact of invasive species and diseases. What starts off as a local decline could lead to a global extinction, and recognising the growing pressures on invertebrates is critical to informing more effective conservation.

Dr Ben Collen, head of the Indicators and Assessments unit at ZSL says: “Invertebrates constitute almost 80 per cent of the world’s species, and a staggering one in five species could be at risk of extinction. While the cost of saving them will be expensive, the cost of ignorance to their plight appears to be even greater”.

The highest risk of extinction tends to be associated with species that are less mobile and are only found in small geographical areas. For example, vertebrate amphibians and invertebrate freshwater molluscs both face high levels of threat – around one third of species. In contrast, invertebrate species which are more mobile like dragonflies and butterflies face a similar threat to that of birds, and around one tenth of species are at risk.

Posted in News

Leave a Reply

Your email address will not be published. Required fields are marked *

*