A Species Crediting Methodology that Supports Conservation Banking for an Endangered Floodplain Minnow

Abstract

Conservation banks are permanently protected lands that contain habitat elements which may be critical to the protection and recovery of federally‐listed species under the Endangered Species Act. These banks are managed in perpetuity and used to mitigate impacts occurring elsewhere to the species' habitat. We developed a species crediting methodology to assess conservation credits and debits for the endangered Oregon chub (Oregonichthys crameri) to support conservation banking. Our methodology is based on prior studies assessing relationships between population abundance and habitat parameters for the species. The methodology also incorporates ratings for piscivory risk, site location, and the abundance and status of existing and proximal populations. Our approach assigns more credits to functioning bank sites that support abundant, stable populations and requires more credits when impacted sites negatively affect these populations. Examples show the credit value calculations for determining baseline conditions and for assessing impacts to species habitat. Additional examples illustrate the incentives for creating habitats that support abundant, stable populations and the incentives for reducing the severity and duration of impacts to habitats. As the demand for economic development of prime fish habitat increases and as more conservation banks are developed, managers may benefit by developing similar crediting methodologies to promote adequate compensatory conservation for imperiled species.