Development of Life-Stage Specific Population Dynamics Models for Lost River and Shortnose Suckers in the Upper Klamath Basin
Project ID: 2-05-FC-10-1192
Federal Agency: U.S. Bureau of Reclamation
Partner Institution: Oregon State University
Fiscal Year: 2005
Initial Funding: $99,498
Total Funding: $99,498
Project Type: Research
Project Disciplines: Biological
Principal Investigator: Markle, Douglas
Agreement Technical Representative: Piaskowski, Richard
Abstract: Lost River Suckers, Deltistes luxatus, and shortnose suckers, Chasmistes brevirostris, are federally listed endangered species endemic to the Upper Klamath Basin of California and Oregon. Knowledge about the dynamics of the Lost River and shortnose sucker populations are essential for developing recovery strategies and evaluating the effect of current and future management actions. The life history characteristics of these species include late age at first maturity, pulse recruitment, long and variable spawning periodicity, and the threat of periodic die-offs due to poor water quality and disease. Researchers from Oregon State University (OSU) and USGS have monitored various life history stages of sucker populations in UKL since 1991. OSU’s ongoing sampling of larval and juvenile life stages has allowed for estimation of survival and production with respect to key physical and environmental variables. Also, recent analyses of adult sucker mark-recapture data have provided estimates of annual survival, recruitment and finite rate of population change. In a cooperative project with USGS, we will develop stage-structured population models to 1) help determine meaningful recovery goals and assess critical life history stages that may inhibit recovery efforts, 2) identify data gaps and help prioritize future research, and 3) evaluate different management practices on the populations and make predictions on which management actions may promote species recovery. The development of these models will involve a critical review of existing datasets for estimation of variance and uncertainty in key life history parameters. Life history stages to be considered will include larvae (pre and post flexion), juveniles and adults. The development of population models that incorporate data from all available life stages will provide valuable tools for natural resource managers in the Klamath Basin to help identify where critical population “bottlenecks” occur and afford resource managers the ability to focus on important habitats or conditions to promote recovery of these species.