Lista Rossa delle specie minacciate in Svizzera: Ortotteri - CH
Lista Rossa delle specie minacciate in Svizzera: Ortotteri - CH
Lista Rossa delle specie minacciate in Svizzera: Ortotteri - CH
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Summary 11<br />
> Summary<br />
The 2007 Red List of threatened Orthoptera of Switzerland was prepared on the basis<br />
of the criteria and categories proposed by the IUCN (2001, 2003). The method used for<br />
assign<strong>in</strong>g <strong>specie</strong>s to threat categories is also an adaptation of the IUCN method (2003).<br />
Of the 105 Swiss <strong>specie</strong>s assessed, 19 (18,6 %) are near threatened (NT) while 40<br />
(39,2 %) are threatened and therefore <strong>in</strong>cluded <strong>in</strong> the Red List. Of these 40 <strong>specie</strong>s, 3<br />
are ext<strong>in</strong>ct <strong>in</strong> Switzerland (RE), 10 are critically endangered (CR), 8 are endangered<br />
(EN) and 19 are vulnerable (VU). The <strong>specie</strong>s most at risk are those found on gravel<br />
banks of alluvial zones and <strong>in</strong> fenlands and raised bogs; these are followed by the<br />
somewhat less severely threatened dry grassland <strong>specie</strong>s.<br />
This new version of the Red List supersedes that published <strong>in</strong> 1994 (Nadig & Thorens<br />
<strong>in</strong> Duelli 1994) and is based on different criteria. This expla<strong>in</strong>s the significant differences<br />
concern<strong>in</strong>g <strong>in</strong> particular the proportion of <strong>specie</strong>s assigned to the lowest threat<br />
categories.<br />
In addition, thanks to an improvement <strong>in</strong> our knowledge of orthopteran fauna of Switzerland,<br />
it was possible to remove certa<strong>in</strong> <strong>specie</strong>s from the Red List, as the populations<br />
<strong>in</strong> question were larger and more stable than had been assumed <strong>in</strong> 1994. At the same<br />
time, comparison of the two lists also gives grounds for concern: there has been a<br />
further deterioration <strong>in</strong> the position of a number of <strong>specie</strong>s that were already severely<br />
threatened <strong>in</strong> 1994.