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Survivor plant becoming extinct

By John Yeld

Cape Town – South Africans are pillaging cycads at such a rate that some species have been driven to extinction and others reduced to just a handful of plants left in the wild.

Cycads, which started becoming popular as ornamental plants in suburban gardens in the 1970s and 80s, are the world’s oldest seed plants with a lineage dating back between 280 and 300 million years – well before the dinosaurs.

They’re sometimes called “living fossils”.

One cycad species of the 38 that occur in this country is now known from just a single hill outside the Kruger National Park. The Albany cycad has been reduced to just 40 specimens in the wild, and another species is now believed to consist of just one specimen in the wild, in the Soutpansberg in Limpopo.

“The reality is that many of them are on the brink of extinction,” international cycad expert and conservationist Professor John Donaldson told an audience during the five-lecture Summer School series on Kirstenbosch national botanical gardens.

Donaldson, who also chairs the cycad specialist group of the IUCN (World Conservation Union), is head of applied biodiversity research at the SA National Botanical Institute at Kirstenbosch, and is also honorary professor holding the Harold Pearson Chair of Botany at UCT.

Pearson was professor of botany at UCT and the founder-director of Kirstenbosch, where he planted most of the cycad collection between 1913 and 1916. The collection can still be seen in the Dell area.

“Cycads have a long legacy of work at Kirstenbosch,” Donaldson said.

New research showed that most early cycad species had become extinct, and modern species had started emerging about 12 million years ago and “gone ballistic” with speciation between 12 and 5 million years ago.

Rather than the “dinosaurs of the plant world”, they were more accurately termed “evolution’s comeback kings” because of this sudden diversification. More than 300 cycad species are now recognised worldwide, with more than 50 percent of them occurring in Mexico, Australia and South Africa.

Until recently cycads were the most threatened group of organisms on Earth, with more than 60 percent of all species on the Red List. However, they have now been overtaken by sturgeon.

Donaldson and fellow researchers had been monitoring some local cycad populations over two decades, he said.

“In every one, they had declined by at least 60 percent, with most declining by 90 percent and some to extinction – at least three species have become extinct in the wild and there are possibly another two as well, all in the past 10 to 20 years.”

The vast majority of the illegal cycad trade occurred within South Africa by South Africans, Donaldson said.

One species in the Waterberg area had been “absolutely pillaged”, down from 6 000 specimens a decade ago to just 2 080 stems in 2008, and with a further loss of an estimated 1 500 stems just two years later.

Draft legislation prohibiting all trade in endangered cycad species was being considered but was “not very popular”, he said. – The Argus