Quantifying allowable harm in species at risk: application to the Laurentian black redhorse (Moxostoma duquesnei)

摘要: 1. When a species is identified for conservation, often the only way to effect recovery reduce harm imposed by stressors threatening survival of species. Ideally all threats would be removed; however, this not feasible or practical. Within context, demographic approach presented assess how much human-induced could allowed without impairing persistence Harm defined as negative perturbation that can target one more vital rates and life stages simultaneously. 2. Allowable harm, level will jeopardize recovery, function affected human actions, sensitivity population growth changes in these (their elasticities), rate prevailing before occurs, set parameters considered safe long-term persistence. This life-history based requires minimal data, link demography with habitat-explicit information, flexible enough encompass complex histories, follows precautionary approach. 3. Quantification allowable applied any at risk. introduced applying it Canadian freshwater fish, black redhorse (Moxostoma duquesnei), demonstrating absence habitat constraints dynamics are most sensitive young adults, but fitness particularly loss used young-of-the-year fish under current levels supply. Copyright © 2009 John Wiley & Sons, Ltd.