One in three species of cactus are at risk of extinction, yet, despite this, there is limited research in the area. The IUCN (International Union for the Conservation of Nature) has only assessed the vulnerability of ~16% of flowering plant species using their red list criteria.
Cacti are threatened by poaching, as well as land use change, climate change and habitat degradation. Certain species are particularly vulnerable to extinction because they are unique to specific places. For example, Angelica Villalobo-Lopez and her colleagues assessed species from the Copiapoa genus (which is endemic to the Atacama desert) and found 41% are critically endangered.
Habitat fragmentation (a consequence of land use change) leads to the geographic isolation of cacti. The resulting populations suffer from inbreeding and reduced genetic diversity, limiting their ability to adapt to climate change and therefore increasing their extinction risk. Poaching exacerbates this by further reducing numbers to levels that are unable to support a population in the long term.
The scale of poaching is difficult to comprehend.
Living Rock (aka Ariocarpus fissuratus) is a small, thornless cactus endemic to the Big Bend region of the Chihuahuan desert, in Texas and north Mexico. Special agents from the U.S. Fish and Wildlife Service, alongside several partner organisations, caught smugglers that poached between 10,000 and 15,000 Living Rock cacti. One individual made more than $300,000 in the space of seven months from their exploits. Living Rock is acutely impacted because the species grows over decades, meaning the poached areas will take a long time to recover, if they ever do.
In the U.S., it is hoped education on the laws, regulations and environmental impacts of cactus poaching will help to protect the plants. In addition, convicting perpetrators will act as a deterrent. In Saguaro National Park, Saguaro cacti have been microchipped to deter would-be poachers and allow stolen ones to be identified, even if laundered into commercial markets.
A main driver of cactus poaching is the high demand from consumers, with cacti being sold to collectors or laundered to be sold at garden centres.
So how can you be sure when purchasing a cactus that it has been sourced sustainably and ethically?
- Avoid protected species. Living Rock is on CITES appendix I, meaning it is at risk of extinction and international trade is illegal. Look up the scientific name of your species here.
- Choose plants that were grown in a nursery, rather than collected from their native habitat.
- Consider growing your own cactus from seed.
By being ethical consumers, we can tackle environmental challenges one cactus at a time.