Universität Bayreuth, Media release, No 003/2021, 15. January 2021
Bayreuth botanists explore the unique flora of New Caledonia
Researchers from the University of Bayreuth have discovered seven new species of the dogbane family of plants (Apocynaceae) in New Caledonia. Following in the footsteps of the British explorer James Cook, they examined the flora on the archipelago in the Southwest Pacific in spring 2019, and have now published the results of their long-term studies in the 27th volume of "Flore de la Nouvelle-Calédonie".
The Bayreuth first authors Prof. Dr. Sigrid Liede-Schumann and PD Dr. Ulrich Meve summarise their studies on New Caledonian Apocynaceae (dogbane family) over more than 200 pages, and present 12 native genera and 29 species with extensive descriptions and identification keys, photo plates, distribution maps, and classifications with regard to IUCN Red List categories.
In the course of this work, they identified seven new species and described them for the first time. Two other species are presumed extinct while three others are highly threatened. Above all, intensive nickel mining, but also the uncontrolled reproduction of introduced maned deer and wild boar threaten the unique vegetation of the islands. Accompanying molecular biology studies have shown that most of the native genera originate from only one species that migrated from Australia or the surrounding islands. However, the most species-rich genus Leichhardtia (19 species) colonised New Caledonia from Australia on two separate occasions.
Liede-Schumann and Meve literally followed in the footsteps of Cook and the two German biologists on board the Resolution, Georg Forster and his father Johann Reinhold Forster, in April 2019, 245 years after the famous discoverers.
Together with their French-New Caledonian cooperation partner and first author of this study, Dr. Gildas Gateblé (IRD, Nouméa), and with the support of the New Caledonian nature conservation authorities, they had the opportunity to enter one of the "original sites" of that time and to analyse it botanically. This revisit of a small coral island off the southern tip of the main island, which was named "Botany Isle" by Cook due to its abundance of plants, was perhaps the only occasion a defined area had been studied for changes in its flora over almost quarter of a millennium - made possible thanks to the diverse collections and records of Georg Forster, who introduced scientific standards even before Alexander von Humboldt. The Bayreuth researchers compared herbarium specimens and text and image sources. The New Caledonian-Bavarian research group was able to find many similarities in flora (and fauna) with the information documented in 1774, but, of course, also some changes. With the obvious decline in the population of the endemic Araucaria columnaris trees, new species found a habitat - but predominantly species of the region itself, and only a few neophytes (introduced, originally non-native plants).
In addition, the question of which of the three islands in the vicinity of Captain Cook's anchorage was actually involved was conclusively determined. The re-analysis of previously misinterpreted nautical information in his logbook revealed that today's Ile Améré is undoubtedly Cook's "Botany Isle", i.e. the island that was entered at the time.
New Caledonia, a group of islands in the Southwest Pacific belonging to France, was only discovered and named by Captain James Cook on his second voyage in 1774. Its soils, which often contain heavy metals, allowed a unique and extremely species-rich flora to develop, comprising approx. 3500 native species, 80% of which only occur there (endemics). In particular, the archipelago has become famous as the home of the only known parasitic conifer Parasitaxus usta, and the most archaic flowering plant living today, Amborella trichopoda.
- GÂTEBLÉ, G., LANNUZEL, G., LIEDE-SCHUMANN, S. & U. MEVE (2020). The flora of James Cook’s ‘Botany Isle’ (Îlot Améré) and the neighbouring islets of Kié and Nouaré (New Caledonia): revisited and re-evaluated after nearly 250 years. Muelleria 39: 39-57.
- LIEDE-SCHUMANN, S., MEVE, U., GÂTEBLÉ, G. (2020). Apocynaceae pro parte (p. 10-233). In LIEDE-SCHUMANN, S., MEVE, U., GÂTEBLÉ, G., BARRIERA, G. & FICI, S.: Flore de la Nouvelle Caledonie, Vol 27: Apocynaceae p.p., Phellinaceae, Capparaceae. Muséum National d'Histoire Naturelle (Paris) & IRD Editions (Marseille), 335 pp.