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Conservation of the endangered Gravel Grasshopper Chorthippus pullus (Philippi 1830) (Orthoptera: Acrididae): A dispersal survey in Central Valais

Project Number: CH-4988

Project Type:	Master
Project Duration:	05/01/2007 - 08/30/2008 project completed
Funding Source:	other ,
Leading Institution:	Universität Bern, Zoologisches Institut
Project Leader:	Prof. em. Jürg Zettel Biologe Speichergasse 8 3150 Schwarzenburg Phone: +41 31 971 34 44

related to this project.

for which the project has a relevance.

Research Areas:

Biodiversity

Disciplines:

zoology

Keywords:
Chorthippus pullus, Gravel Grasshopper, Acrididae, Orthoptera, Pfynwald, corridor, alluvion, marking, capture-recapture, migration, habitat quality, habitat-management, distribution

Abstract:
The dispersal ability of the critically endangered Gravel Grasshopper Chorthippus pullus (Orthoptera : Acrididae) (Philippi 1830) was investigated in a population in Central Valais (Switzerland, VS). In November 2006 a corridor was cut from the Russenbrunnen clearing, which is of suboptimal habitat structure, through 40 m of dense forest. It offered a way for the decreasing C. pullus population, to nearby riverbanks with optimal habitats in different succession stages and water dynamics. The aim of this study was to investigate if individuals from the clearing would emigrate from their suboptimal relic habitat into the optimal habitats along the River Rhone with its natural dynamics. 450 Gravel Grasshoppers were individually marked as soon as they were adult, with a pattern of colour dots on the pronotum as well as with reflective tape on the outer side of the hind femora. 14 individuals crossed the 50 m long corridor ; 50 individuals migrated into the corridor. The average dispersal distance and several maximum values are bigger than cited in other recent studies about C. pullus (Janssen 1993, Schwarz-Waubke 1998), probably caused by the clearing’s suboptimal habitat structure. The actual distribution of C. pullus at Pfynwald was mapped. Compared to the years shortly after the peak flood in 2000 the population has extended its range, now inhabiting the bigger part of the right riverbanks of the Rhone between Leuk and Sierre.

Leading questions:
Do Gravel Grasshopper migrate through a corridor to join optimal habitats in Pfynwald?

Publications:
Roesti C. 2008. Conservation of the endangered Gravel Grasshopper Chorthippus pullus (Philippi 1830) (Orthoptera: Acrididae): A dispersal survey in Central Valais. Zoologisches Institut, Abteilung Synökologie, Universität Bern


Last update: 12/29/16
Source of data: ProClim- Research InfoSystem (1993-2024)
Update the data of project: CH-4988

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