Thirty-one percent of cactus species are threatened with extinction, according to the first comprehensive, global assessment of the species group by IUCN and partners, published today in the journal Nature Plants.
This places cacti among the most threatened taxonomic groups assessed on The IUCN Red List of Threatened Species™ – more threatened than mammals and birds.
According to the report, cacti are under increasing pressure from human activity, with more than half of the world’s 1,480 cactus species used by people. The illegal trade of live plants and seeds for the horticultural industry and private collections, as well as their unsustainable harvesting are the main threats to cacti, affecting 47% of threatened species.
Professor Kevin Gaston, Director of the Environment and Sustainability Institute at the University of Exeter’s Penryn Campus, who co-led the Global Cactus Assessment, said: “The startling results reflect the vital importance of funding and conducting assessments of the threatened status of all of the species in major groups of plants, such as the cacti.
“Only by so doing will we gain the overall picture of what is happening to them, at a time when, as evidenced by the cacti, they may be under immense human pressures.”
“These findings are disturbing,” said Inger Andersen, IUCN Director General. “They confirm that the scale of the illegal wildlife trade – including trade in plants – is much greater than we had previously thought, and that wildlife trafficking concerns many more species than the charismatic rhinos and elephants which tend to receive global attention. We must urgently step up international efforts to tackle the illegal wildlife trade and strengthen the implementation of the CITES Convention on International Trade in Endangered Species, if we want to prevent the further decline of these species.”
Other threats to cacti include smallholder livestock ranching affecting 31% of threatened species, and smallholder annual agriculture affecting 24% of threatened species. Residential and commercial development, quarrying and aquaculture – particularly shrimp farming, which expands into cacti’s habitats – are also among major threats faced by these species.
Cacti are key components of New World arid ecosystems and are critical to the survival of many animal species. They provide a source of food and water for many species including deer, woodrats, rabbits, coyotes, turkeys, quails, lizards and tortoises, all of which help with cactus seed dispersal in return. Cactus flowers provide nectar to hummingbirds and bats, as well as bees, moths and other insects, which, in turn, pollinate the plants.
Continue reading at the University of Exeter.
Cactus image via Shutterstock.