Charles Darwin Research Station
Press Contact For Immediate Release
Paola Díaz
Information Officer
Charles Darwin Research Station
Galapagos-Ecuador
E-mail:
infocdrs@fcdarwin.org.ec
Phone: 593-5-526-147/146
Fax: 593-4-564636
Galapagos scientists find thriving population of rare plant in remote volcanic crater
June 2000
Santiago Island is one of the islands worst affected by introduced species in Galapagos. Its native vegetation communities have been devastated by introduced goats, donkeys and pigs. Santiago is one of the only two Galapagos islands from which an endemic plant species (one found only on that island) has become extinct. Many more of Santiago’s plants are now on the brink of extinction, including Scalesia atractyloides, which was indeed believed extinct until, in 1995, a tiny group of plants of one of its two subspecies (S. a. darwinii) was found on an inaccessible cliff. The site was fenced and two plants remain. In 1997, two plants of the other subspecies (S. a. atractyloides) were found, on a similarly inaccessible cliff, and this new site was also fenced.
During April last year, a few unusual Scalesia plants were found in an area of broken lava in an inaccessible part of Santiago, probably never before visited by botanists. These small trees were subsequently identified as S. a. atractyloides, an exciting find which considerably increased the known population. An extensive survey by the Charles Darwin Research Station team found a total of 70 plants, scattered over a wide area. The various small groups of plants were assessed for the possibility of enclosing some by fencing, to protect them from goats.
The team then proceeded to survey a further section of the coast, parts of which had not been visited by botanists for more than 30 years, if ever. The area surveyed included the site of a record made more than 30 years ago of Scalesia atractyloides and S. stewartii (a more common species) at the same site, a situation that would be extremely unusual, since normally only one species of the genus occurs in a given place. It seemed likely that one of the records was erroneous, since the two species are similar in appearance, and most likely that the erroneous record was of S. atractyloides, since the site is close to the main area of distribution of S. stewartii and far from the nearest S. atractyloides. Nevertheless, the CDRS scientists decided to re-check the site, in case S. atractyloides may really have been present and still survive.
The site is an old tuff cone, some distance from the coast of this uninhabited island. Disembarking at dawn, the team hiked many hours over rough lava to reach and climb the cone. Upon reaching the crater rim, the effort was rewarded with a spectacular discovery: the crater was full of mature trees of Scalesia atractyloides! The plants found seemed to be of S. a. darwinii, and during a follow-up visit the population was estimated at 445 adults and 2350 young plants: an apparently healthy population.
This further exciting discovery therefore increases the total population of this subspecies from 2 to almost 500 mature plants. With the increase in known S. a. atractyloides from 2 to 70, there is a real chance to save both varieties of this species, which once seemed doomed to extinction. CDRS senior botanist, Dr Alan Tye, commented, "We are delighted that S. atractyloides has lost the dubious distinction of being the rarest plant of Galapagos!"
The surveys described in this press release are part of a CDRS project to locate and monitor populations of rare plants, especially in areas that have seldom, if ever, been visited. The objective is update our knowledge of the abundance and distribution of the rarest endemic species (those found only in Galapagos), so as to plan the conservation of the most threatened species. Funding for the plant conservation programme is provided by the British Government’s Darwin Initiative for Biodiversity Conservation, Frankfurt Zoological Society, Keidanren Nature Conservation Fund, Lindblad Expeditions’ Galapagos Conservation Fund and the Galapagos Conservation Trust.