Application of extinction risk and conservation criteria for assessing fish species in the lower La Plata River basin, South America

摘要: The Lower La Plata River basin contains between 160 and 260 native species depending on the river segment, with a few stretches containing locally endemic species. Extinction risk analysis for 185 freshwater fish in lower is presented first time basis of regionally standardized International Union Conservation Nature (IUCN) Red List criteria compared alternative methods within region. There were 11 threatened (6%), which three considered as Endangered eight Vulnerable. A further rated Near Threatened; while 121 (66%) assessed being Least Concern, 49 (26%) remained Data Deficient. application regional guidelines after using global did not change categories established. The IUCN B considerable challenges because insufficient information, criterion C inapplicable; whereas D proved valid five instances where found highly restricted geographical range only inhabiting small streams. The use other approaches, such Sum Index (SUMIN) method Assessment Method Threat Degree (MEGA), resulted an 11% agreement results main commercial recreational target species. The discrepancies may be explained that former measures extinction by population decline criterion, latter two put more emphasis assessment intrinsic vulnerability threat status, these additional incorporated order to define conservation priorities. Further research strongly recommended improvement based better ecological particularly data non-target tributaries, wetlands, headwaters across basin. Copyright © 2012 John Wiley & Sons, Ltd.