By Liz Kimbrough
- The Chapman’s pygmy chameleon, about the length of a golf tee, was first described in 1992 and not seen again in the wild by scientists until 2016.
- An estimated 80% of the rainforests of Malawi Hills, where the chameleons live, have been destroyed over the past 40 years, mostly for agriculture.
- The chameleon is listed as critically endangered and the remaining populations are isolated, leaving them are at risk of losing genetic diversity.
- The researchers are calling for more surveys and monitoring of the chameleon populations as well as conservation action to safeguard what remains of the chameleon’s habitat.
One of the world’s smallest and rarest chameleon species has been rediscovered in Malawi, living on the edge of extinction in just a few, scant patches of rainforest.
“They are little, gentle creatures,” Krystal Tolley, a professor from the South African National Biodiversity Institute and the University of the Witwatersrand and member of the expedition, said in a press release. “Other chameleon species can be hysterical, hissing and biting, but pygmy chameleons are gentle and just beautiful.”
The tiny Chapman’s pygmy chameleon (Rhampholeon chapmanorum) grows to about 5.5 centimeters (2.2 inches), no longer than a golf tee. The species was first described in 1992 and was not seen again by scientists until 2016, when researchers from the South African National Biodiversity Institute and the Museums of Malawi searched for the cryptic chameleons in their rainforest habitat. Their findings have now been published in the journal Oryx.
An estimated 80% of the rainforests of Malawi Hills, in southern Malawi where the chameleons live, have been destroyed over the past 40 years, mostly for agriculture. An area roughly the size of 100 football fields is all that remains.
Under the threat of an ever-vanishing habitat, researchers feared that the chameleon may already be extinct, so they turned to crowdfunding to raise the money needed to survey the area for any surviving chameleons. Chameleon supporters rallied for the cause and the team raised enough funds to search for chameleons in the Malawi Hills.
The researchers surveyed two of five remaining forest patches and found 17 adult chameleons. There are likely more, the paper states, but one of the forest patches is a sacred ancestral burial ground where the researchers were not permitted to leave the narrow footpath. The team also revisited an area in Mikundi, about 75 kilometers away, where captive-bred chameleons were released in 1998. There, they found 21 adult chameleons, and 11 juveniles and hatchlings living in the forest.
“The first one we found was in the transition zone on the forest edge, where there are some trees but mostly maize and cassava plants. When we found it we got goosebumps and just started jumping around,” Tolley said. “We didn’t know if we would get any more, but once we got into the forest there were plenty, although I don’t know how long that will last.”
The Malawi Hills, where the chameleons live, have seen massive deforestation over the past few decades. Pink blocks show forest loss from 2001-2012. Image courtesy of Global Forest Watch. Click to enlarge.
Chapman’s pygmy chameleons spend most of their time on the forest floor, so unlike many of their tree-dwelling kin, they lack a prehensile tail. They mostly keep to the ground, amongst the leaf litter, or sleep low in bushes, where their leaf-like appearance comes in handy as camouflage.
“They are mostly brown but they can change to quite beautiful blues and greens with little dots all over them and that’s probably a way of communicating with each other,” Tolley said. “They also vibrate and we could feel it when we held them. We don’t really know why but it’s also probably some form of communication. The fact they do it while held in our hands could mean it’s a way to try and scare predators.”
A 2014 assessment of the world’s chameleons found that 36% of the world’s chameleons are threatened with extinction. The Chapman’s pygmy chameleon was listed among the rarest. It is is now listed as critically endangered on the IUCN Red List.
The remaining populations of pygmy chameleons are not able to travel the long and exposed distance between forest fragments to mate, leaving them at risk of becoming genetically isolated. Genetic testing of the rediscovered chameleons revealed that while it hasn’t happened yet, this constriction in the gene flow between the isolated populations will likely reduce their genetic diversity over time.
“The forest loss requires immediate attention before this species reaches a point from which it cannot return,” Tolley said. “Urgent conservation action is needed, including halting of forest destruction and recovery of habitat to promote connectivity.”
The researchers are calling for more surveys and monitoring of the chameleon populations as well as conservation action. They suggest including what is left of the forest into the Matandwe Forest Reserve, so it can be safeguarded, both for the future of the chameleon and for all of the diversity the forest supports.
Tolley, K. A., Tilbury, C. R., Da Silva, J. M., Brown, G., Chapeta, Y., & Anderson, C. V. (2021). Clinging to survival: Critically endangered Chapman’s pygmy chameleon (Rhampholeon chapmanorum) persists in shrinking forest patches. Oryx. doi:10.1017/S0030605320000952
Banner image of the Chapman’s pygmy chameleon by Krystal Tolley.
Liz Kimbrough is a staff writer for Mongabay. Find her on Twitter: @lizkimbrough_
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