This is an online reprint. Please cite as: Riede, K. (1990): Orthopterological studies in eastern Ecuador. Metaleptea 12, 4-5.

Please note the author's new address (as by Jan 2003):

Klaus Riede Zoologisches Forschungsinstitut und Museum Alexander Koenig Adenauerallee 160 53113 Bonn GERMANY

ORTHOPTEROLOGICAL STUDIES IN EASTERN ECUADOR (part 1)

Klaus Riede Zoologisches Institut Albertstr. 21a W-7800 Freiburg F.R.G.

Despite its small area, Ecuador is a country of megadiversity and must be considered to be a real laboratory of evolution. Besides the well-known Galapagos islands, the mainland contains an archipelago of "habitat islands", mainly determined by microclimate and altitude. Two Andean chains separate the great blocks of Pacific and Amazon rainforest, including all the ecological gradients from upper montane to lowland forest. The Amazonian part of Ecuador comprises 48% of the national territory. The area was nearly forgotten until 1967, when the discovery of oil stimulated the "development" of the region. Since then, public interest has shifted to the "Oriente"; roads were built and boom- towns came into being. With six indigenous lowland tribes, among them the warlike Waorani, the region is still considered to be wild and dangerous, and certainly the naturalist hopes that this will remain so. When I first visited the Oriente in 1983, I planned to study communication behaviour in Acridoidea. Financed by the department of Prof. Huber at the Max-Planck-Institute for behavioral physiology in Seewiesen, my project and my background were ethology and behavioural physiology. Having been imprinted with a European image of a grass-feeding, stridulating gomphocerine grasshopper, my first encounter with forest grasshoppers was frustrating. Most species of Amazonian "grasshoppers" live up in the canopy, thus in no way confined to "grass", but feeding on dicotyledonous trees and epiphytes. Many species are brachypterous or apterous, with big eyes and long tarsi. Their unability to stridulate made my taping equipment superfluous, and I was quite happy when I finally found Peruvia nigromarginata, which is one of the few gomphocerine species and has a complex courtship behaviour comprising optical and acoustical elements, similar to its well- known Old World relatives. This species inhabits riversides and patches of secondary growth. These "light-gaps" are generated by fallen trees and go through a characteristic succession of plants - and grasshoppers! This fauna of pioneer species is much less diverse than that of the canopy, but several interesting species were represented with sufficient abundance for behavioural studies. Back to Europe, I contacted Christiane Amédégnato in Paris to determine voucher specimens from my behavioural studies and some other grasshoppers found in the old field communities and in the tops of freshly cut trees. To our surprise, this material contained several undescribed species and was distinctly different from the Peruvian material collected by C. Amédégnato and Marius Descamps. We realized that there were a lot of endemisms to expect in Ecuador which stimulated my hunting fever. Since then, on each field trip to Ecuador I dedicated some time to looking for unknown grasshoppers in the tree tops. There are lots of possibilities for getting material from there. Descamps collected systematically by cutting a hectar of forest. However, this is too expensive for a one-man expedition. Besides, it seemed senseless to cut trees in an area under heavy environmental stress, where new roads were being built daily. I therefore concentrated on searching in freshly cut trees along roads or in fields made for subsistence farming by the indigenous population. Ecuadorian Amazonia is far from homogeneous. Several volcanoes rise above the Amazon lowland forest, andtheir specific mountain forests harbour a great variety of unknown endemic species. The altitudinal border for canopy grasshoppers is not known exactly - I collected specimens up to 1200 m which would mean that a lot of endemisms are to be expected in isolated mountain forests like those which girdle the volcanoes like Sangay, Sumbaco and Reventador, or the sub-Andean mountain chain of the Cordillera de Cutucú. In the following contributions to this miniseries I will describe my experience during several field trips between 1983 and 1989, especially indigenous people of the Siona - Secoya tribe, and give preliminary reports about the material collected and analysed. For anyone interested, most of this material is now deposited in the Muséum National d`Histoire Naturelle de Paris, and duplicates can be found in the laboratory of the PUCE, the Pontifica Universidad Católica del Ecuador, Quito, and at the Senckenberg Museum, Frankfurt/M, F.R.G. Most of it are Acridoidea, but a considerable number of Tettigoniidae has been collected, too.

 
Last update: Klaus Riede, 5.2.2008